Meteor Showers, Mars Missions & the Mystery of Stranded Astronauts

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Andrew Dunkley: Hi there. Thanks for joining us. This is

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Space Nuts, where we talk astronomy and space

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science, uh, every week, uh, on

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various topics. And the topics of the day,

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uh, this week include meteor showers.

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Uh, there's one happening as we speak and

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another one coming up which, uh, we'll be

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talking about. Uh, the Mars

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Escapade mission is, um,

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on its way. Uh, we talked about that, I think

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a week or two ago, wondering, uh, because

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they were running into a bit of trouble. But,

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um, I think they're all systems

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go now. Uh, but this is, uh, not

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all systems go. This is involving Chinese

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astronauts, uh, that are stranded on their

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space station. And we're going to chase some

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stars using a process called

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gyrochronology. That's all coming up

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in this episode of space nuts.

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Voice Over Guy: 15 seconds. Guidance is internal.

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10, 9. Ignition

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sequence start. Space nuts. 5, 4,

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3, 2. 1, 2, 3, 4, 5.

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Space nuts. Astronauts report it feels good.

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Andrew Dunkley: And joining us again to go through all of

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that is Professor Jonti Horner, professor of

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Astrophysics at the University of Southern

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Queensland. Hi, Jonti.

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Jonti Horner: Good morning. How are you going?

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Andrew Dunkley: I am well. Good to see you. Love your T

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shirt.

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Jonti Horner: Fc. Yeah. So much for the outreach.

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T shirts today. I was groggy when I woke up

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and football talks just feel so comfortable.

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Andrew Dunkley: Yeah, they do, don't they?

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Jonti Horner: Yeah. You pay a lot of money for them, I've

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got to say that. But they last forever. I've

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still got some from kind of more than 20

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years ago that are wearable, which can't say

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for most of the clothes I buy.

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Andrew Dunkley: Well, my, uh, I've got three football

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shirts and they're all wonderful. Cincinnati

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Bengals, the Manly, uh, Waringa Sea

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Eagles, and the New South Wales Blues,

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although I don't get to wear that one very

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much. Uh, and, uh, I've got

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four golf shirts that I wear just

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when I'm playing. And they're. They're all

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the most comfortable shirts I've got.

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Jonti Horner: So.

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Andrew Dunkley: I agree.

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Jonti Horner: Does remind me of the Sam Vines,

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um, Law of Boots, which became a rallying

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cry in the UK about the cost of living thing.

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So this is another Terry Pratchett thing.

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Although I think it's like most things Terry

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Pratchett did, he was drawing on the wisdom

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of people who came before as well as being

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very wise himself, but talking about the,

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the, um, impacts of poverty and the fact that

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he could never get his boots to last more

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than, you know, one season, wandering around,

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being a copper, walking around on the cobble

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streets of an park. And he paid $10 for a

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pair of boots every time. Um, but the tough.

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The wealthy would pay $50 for a pair of boots

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that would last a lifetime. And so very

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quickly he became poorer because he was

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continually having to buy cheap boots and

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spending more money on the boots. And this

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actually became part of a big campaign in

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the UK for reducing the cost of food and

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looking after people who were in poverty, led

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by a really interesting person called Jack

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Monroe, who's a bootstrap cook, who is

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someone who's been in quite severe poverty

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and has had a number of cookbooks about how

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to eat well at an incredibly low, uh,

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price, you know, from the bargain bin at the

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supermarkets and stuff like that. And I think

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for a while that campaign had a really kind

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of strong backing and made a certain

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amount of social change all off the back of

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the idea that the cheaper something is, the

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less time it lasts, so the more you'll end up

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spending in the long term. Yes, great

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example. You get what you pay for.

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Andrew Dunkley: Well, yeah, absolutely true. Um, my wife

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spends a lot of time researching ways of

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reducing our grocery bill. And she,

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she found a woman in the United States who

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does it for a super cheap,

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um, monthly figure, uh, and she

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translated that into Australian dollars and

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went, I'm going to try this. And I think

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we're up to months 23, and

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we, we're doing really well. And it's, it's

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knocked hundreds of dollars off our monthly

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spend. It's quite remarkable that we can do

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it the way we've, we've done it. And, um,

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yeah, m. I'm, I'm very happy with the

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results. The food's great and, uh, we're

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doing it uber cheap.

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Jonti Horner: Well, it's always fighting. I think there's a

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real conflict with the kind of cost of living

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crisis, but also the fact that people are

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working harder and longer than ever these

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days. True. Because one of the ways to reduce

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your spend on food is to cook everything from

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scra. You get the veggies and the meat and

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the spices and make every meal yourself from

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scratch. But the, you get the less time

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you've got for that, so the more tempting,

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the kind of prepackaged, less healthy, more

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expensive options, uh, are. Because you've

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got that sunk cost, not sunk cost fallacy,

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but you've got that cost of the time that is

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available to you, which, yes. On the money

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you have to spend. It's all really bizarre

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and intertwined and all this stuff that I

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didn't realize as a teenager when I was so

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keen to be grown up well, like.

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Andrew Dunkley: When we were kids, you bought food and it

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costs what it costs to put on the shelf plus

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the profit margin. Um, but

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now they build in all these loyalty programs

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and points programs and all these other

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things that increase the price and

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it's all hidden. And if you're not

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one of those customers that joins the loyalty

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program, you're actually

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bankrolling everybody else who's a part of it

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because you're still paying the extra.

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Jonti Horner: It's, I mean that's all an interesting one

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online and we are totally off topic. Yeah, we

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are. But discussion online the other day

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about the fact that a certain brand of soft

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drink over here in Australia is cheaper to

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buy in 1.25 liter bottles and 600 mil

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bottles, yet everybody will grab the 600 mil

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bottle because of the convenience and all the

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rest of it. Um, and they typically have the

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1.25 liter bottles somewhere else in the

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store and all this stuff. Yeah, yeah. It's

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just bizarre how willing we are

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to just, I don't know, buy into that kind of

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thing and not even think about it. Because

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convenience has a cost.

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Andrew Dunkley: Yes. But when they put a 30 pack of

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um, of whatever on the shelf in a, in a

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big carton at 50 bucks, there's

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no, there's no way, no way I'm

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spending 50 bucks on a carton of Coke or

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whatever. Yeah, that's, that's outrageous.

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Okay, we better get on with it.

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Um, now, uh, something is uh, making the

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news at the moment. It's the Leonid meteor

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shower, uh, which uh, has kind of

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reached its peak now. So by the time some

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people hear this, it may be long past. But

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uh, it's a really good one because it's had

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some, some big highs in years

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past, maybe not so much this year. But

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uh, it, it's sort of one of the big ones,

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isn't is, I.

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Jonti Horner: Mean it's another example. I always, whenever

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there's a meteor shower making the news and

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it seems to happen more and more often thanks

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to the um, click

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starved industry in the Northern hemisphere,

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wanting every click there come from people on

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social media. Um, every meteor shower that

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comes along gets a lot of stories written

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about this is the best one of the year and

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you need to go out and see it and the sky

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will fall and I get grumpy. Um,

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the Leonids are not the best meteor shower of

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the year except when they are and the year is

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the years when they're not. What I mean by

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this is that many ah, of the meteor showers

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we see that are the really reliable annual

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ones are uh, meteor showers where

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we are not passing exactly where the comet

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has passed. We're passing through a tube of

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debris that has spread out from the comet's

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orbit over very long periods of time.

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And so in a typical year the material we go

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through has about the same density as the

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last year, so we get about the same number of

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meteors. So you can imagine for example the

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Orionids and the Yteraquarids which are born

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of Comet Hallie, or you can imagine the

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Perseids born of Comet Swift Tuttle, where

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you've got these Hallie type comets that have

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been trapped on their current orbits or

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thereabouts for thousands of years. Every

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time they go around the sun they lay down

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trails of dust that currently wouldn't

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intersect the Earth because the comets orbits

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come close to the Earth but they don't

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exactly cross us. But over time that dust has

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spread out and you've got these tubes that

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are tens of millions of kilometers, even 100

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million kilometers across in three

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dimensions. So we run through the tube, but

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not where the comet currently is. And so

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we're getting the dust after it's spread out

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for a good long period of time. With the

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perses, you occasionally get enhancements

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when the comet's relatively nearby because

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the dust is a bit denser. And that's because

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comets with Tuttle's ah, orbit comes a bit

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closer to perfectly intersecting the Earth's

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orbit than Comet Halley's does. And so we do

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get a bit more variability there. With

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the Leonids we've got a slightly different

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situation. The meteor stream itself is

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younger, which I would argue suggests that

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the parent comet, 55P Temple Tuttle,

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hasn't been trapped on its current orbit for

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as long, so it hasn't had time to lay down as

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much debris. It's also a smaller comet, so

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it's laying down a bit less material every

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time it goes around the sun. But the Earth's

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running into the debris from that comet

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pretty much head on. Which means that the

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particles from Comet Temple Turtle hit the

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Earth's atmosphere at about the maximum speed

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anything can and still be bound to the solar

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system. So these meteoroids hit at 71,

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72 km a second and that means they're

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typically a bit brighter for a given size

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than other meteor showers. So in other words,

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we can see the smaller bits of dust and that

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helps give a bit of a boost to the rate that

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you'd see. But typically in an average year

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the Leonids would give you between 10 and 15

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meters per hour as a zenithal

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hourly rate. And the zenithal hourly rate is

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this magic number that astronomers use to

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quantify how strong a meteor shower is to

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compare it with other meteor showers. It is

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the theoretical maximum number of meteors you

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would see if you have perfect eyesight,

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if you have perfectly dark skies and

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perfectly clear skies. And the radiant of the

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meteor shower, the point from which all the

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meteors appear to diverge was directly

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overhead. So in reality, whenever you see a

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ZHR listed for a meteor shower, you probably

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will see fewer meteors than that in an hour.

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Except for the fact that meteors are like

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buses. You'll wait five minutes and three

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will come along at once. And so with that bit

255
00:09:54.460 --> 00:09:56.020
of noise, you may occasionally get an hour

256
00:09:56.020 --> 00:09:57.580
where you get a bit higher rate and then the

257
00:09:57.580 --> 00:10:00.140
next hour will be a bit lower. So typical

258
00:10:00.140 --> 00:10:02.740
year leonids give you 10 to 15 an hour.

259
00:10:03.060 --> 00:10:05.780
But the Earth intersects very well with

260
00:10:05.940 --> 00:10:08.840
the orbit of comet Temple Tuttle, which means

261
00:10:08.840 --> 00:10:10.880
that in theory there's a very small chance at

262
00:10:10.880 --> 00:10:12.400
some point in the future the thing could hit

263
00:10:12.400 --> 00:10:14.340
us, but it probably won't. Almost certainly,

264
00:10:14.340 --> 00:10:16.520
uh, it won't. A bit like Swift Tuttle's a

265
00:10:16.520 --> 00:10:18.960
similar situation actually, but Comet Temple

266
00:10:18.960 --> 00:10:21.800
Tuttle's more pronounced. What

267
00:10:21.800 --> 00:10:24.159
that means is that the debris that has been

268
00:10:24.159 --> 00:10:26.480
laid down by comic Temple Tuttle in very

269
00:10:26.480 --> 00:10:29.440
recent times at previous orbits can actually

270
00:10:29.440 --> 00:10:31.520
interact and hit the Earth, uh, if we're

271
00:10:31.520 --> 00:10:34.160
lucky, on the first lap after it was dropped

272
00:10:34.160 --> 00:10:36.490
or the second lap after it was dropped. And

273
00:10:36.490 --> 00:10:38.770
what happens with the dust released from a

274
00:10:38.770 --> 00:10:41.090
comet is that, uh, it spreads out ahead and

275
00:10:41.090 --> 00:10:43.730
behind the comet in its orbit relatively

276
00:10:43.730 --> 00:10:45.770
quickly. So if you eject a dust grain from

277
00:10:45.770 --> 00:10:48.250
the comet in the forwards direction when the

278
00:10:48.250 --> 00:10:50.770
comet's near perihelion, that dust grain will

279
00:10:50.770 --> 00:10:52.450
be going quicker than the comet, so will

280
00:10:52.450 --> 00:10:54.690
therefore move on a longer period orbit. And

281
00:10:54.690 --> 00:10:56.490
by the time the comet comes back, that dust

282
00:10:56.490 --> 00:10:58.170
will be behind the comet and it will arrive

283
00:10:58.170 --> 00:11:00.410
after the comet. And similarly, any dust

284
00:11:00.410 --> 00:11:02.850
that's ejected backwards will, will be moving

285
00:11:02.850 --> 00:11:04.650
slower than the comet, it will have a shorter

286
00:11:04.650 --> 00:11:06.130
orbit than the comet and it will come back

287
00:11:06.130 --> 00:11:08.570
before the comet. So what this means is that

288
00:11:08.570 --> 00:11:10.610
you effectively get almost like these spears

289
00:11:10.610 --> 00:11:12.930
or javelin shaped streams of

290
00:11:13.250 --> 00:11:15.330
dust where there is a lot more dust,

291
00:11:16.050 --> 00:11:17.730
which is the dust that was laid down in the

292
00:11:17.730 --> 00:11:20.250
previous orbit. And these spikes will be

293
00:11:20.250 --> 00:11:22.170
millions of kilometers long, but relatively

294
00:11:22.170 --> 00:11:25.130
narrow in space initially. It takes them

295
00:11:25.130 --> 00:11:27.370
a long time to spread out. And um, that's the

296
00:11:27.370 --> 00:11:29.610
dust that's been pumped into the wider stream

297
00:11:29.610 --> 00:11:31.450
that when it diffuses and spreads out will

298
00:11:31.450 --> 00:11:33.920
form the wider meteor stream. Now because

299
00:11:33.920 --> 00:11:36.080
these spikes are really, really narrow in

300
00:11:36.080 --> 00:11:38.560
space, we either hit them or we miss them.

301
00:11:38.640 --> 00:11:40.360
And if we miss them, there's nothing to write

302
00:11:40.360 --> 00:11:42.080
home about. But if we run through one of

303
00:11:42.080 --> 00:11:44.160
these spikes, we'll get enhanced

304
00:11:44.560 --> 00:11:47.320
meteor numbers. And the more material in the

305
00:11:47.320 --> 00:11:49.400
spike, the higher the rates we'll get. And

306
00:11:49.400 --> 00:11:51.560
that's why the Leonids are the source of some

307
00:11:51.560 --> 00:11:53.240
of the most famous and most spectacular

308
00:11:53.240 --> 00:11:55.720
meteor storms of all time. We're talking

309
00:11:55.720 --> 00:11:57.596
about years like 1799,

310
00:11:57.844 --> 00:12:00.660
1833, Hades of really famous one

311
00:12:00.660 --> 00:12:02.100
because that was a storm that was visible

312
00:12:02.100 --> 00:12:04.740
over the Americas with more than 100,000

313
00:12:04.740 --> 00:12:07.620
meteors per hour, where light in the sky

314
00:12:07.620 --> 00:12:09.380
was bright enough to wake miners who were

315
00:12:09.380 --> 00:12:11.900
camped outside, their minds in tents. And it

316
00:12:11.900 --> 00:12:14.620
had the uh, more religious side of people in

317
00:12:14.620 --> 00:12:16.660
the US convinced that the apocalypse had

318
00:12:16.660 --> 00:12:18.740
come, that the end times had arrived. Yeah,

319
00:12:18.740 --> 00:12:20.420
ah, the judgment day had come. You know,

320
00:12:20.420 --> 00:12:23.340
people were terrified. So that was utterly

321
00:12:23.340 --> 00:12:25.220
fascinating. But at the same time that was

322
00:12:25.220 --> 00:12:27.260
very much kind of the birth of modern meteor

323
00:12:27.260 --> 00:12:29.780
science because people studied it, figured

324
00:12:29.780 --> 00:12:32.420
out what was going on. The

325
00:12:32.420 --> 00:12:34.180
Leonids have a really important part in our

326
00:12:34.180 --> 00:12:37.180
meteor history. There were big storms in 1965

327
00:12:37.180 --> 00:12:39.660
and 1966. After about a century

328
00:12:39.980 --> 00:12:42.540
of nothing, there was big storm in 1866,

329
00:12:43.020 --> 00:12:45.700
then the next two 33 year periods, the

330
00:12:45.700 --> 00:12:48.580
comets orbital periods, about 33 years pass

331
00:12:48.580 --> 00:12:50.220
with a whimper rather than a bang.

332
00:12:51.740 --> 00:12:54.180
1965, nobody really expected anything, but

333
00:12:54.180 --> 00:12:56.060
there was a big outburst of bright meteors.

334
00:12:56.480 --> 00:12:58.800
And then in 1966 there was a big storm.

335
00:12:59.280 --> 00:13:01.760
So by the time the late 90s came along,

336
00:13:02.720 --> 00:13:05.560
we had this huge industry of researchers

337
00:13:05.560 --> 00:13:08.200
studying the lean in meteor shower, trying to

338
00:13:08.200 --> 00:13:09.680
predict what would happen in

339
00:13:09.680 --> 00:13:12.800
1999-2000-2001-2002,

340
00:13:13.280 --> 00:13:16.040
and developing this kind of modeling theory

341
00:13:16.040 --> 00:13:18.320
based on those javelins of dust, effectively

342
00:13:18.320 --> 00:13:19.960
based on modeling the dust after it was

343
00:13:19.960 --> 00:13:22.600
ejected to predict when we'll cross

344
00:13:22.600 --> 00:13:24.520
trails. And they did a fairly good job of

345
00:13:24.520 --> 00:13:26.520
predicting the strength of and um, the time

346
00:13:26.520 --> 00:13:28.800
of the big outbursts, the last one of which

347
00:13:28.800 --> 00:13:30.920
was in 2002 where there were a few thousand

348
00:13:30.920 --> 00:13:33.920
meteors per hour. Since then, rates have

349
00:13:33.920 --> 00:13:36.440
gone back to normal, um, occasionally.

350
00:13:36.760 --> 00:13:39.000
Now we have the potential of crossing

351
00:13:39.400 --> 00:13:41.320
streams. Now the comet doesn't pass

352
00:13:41.320 --> 00:13:43.520
perihelion for another eight years, so we're

353
00:13:43.520 --> 00:13:45.120
still far away from that. So we wouldn't

354
00:13:45.120 --> 00:13:47.200
expect a big outburst in the next year or

355
00:13:47.200 --> 00:13:49.360
two. But we're starting to get to the point

356
00:13:49.360 --> 00:13:51.240
where we might clip the ends of these spares

357
00:13:51.240 --> 00:13:53.400
in space. And start seeing enhanced threats.

358
00:13:53.400 --> 00:13:55.800
Now the bad news for everybody is that, uh,

359
00:13:55.800 --> 00:13:57.780
Jupiter and Saturn are conspiring to nudge

360
00:13:57.780 --> 00:13:59.500
the orbit of the comet around. And we

361
00:13:59.500 --> 00:14:01.220
probably won't get another great lean in

362
00:14:01.220 --> 00:14:04.020
storm until 2099. But we will

363
00:14:04.020 --> 00:14:05.980
see some enhancement in rates through the

364
00:14:05.980 --> 00:14:08.140
early 2000s and again in the early to

365
00:14:08.140 --> 00:14:11.060
mid-2060s. Um, from the stream.

366
00:14:11.700 --> 00:14:13.860
All that comes back to this year's shower.

367
00:14:13.860 --> 00:14:15.740
This year's shower was forecast to be fairly

368
00:14:15.740 --> 00:14:18.100
average, but we did have three or four

369
00:14:18.100 --> 00:14:20.340
potential very old stream crossings. Forecast

370
00:14:20.340 --> 00:14:22.220
one back on the 9th of November, and I've not

371
00:14:22.220 --> 00:14:24.410
seen anything about that that would be very

372
00:14:24.410 --> 00:14:26.290
weak because that was dust laid down in

373
00:14:26.290 --> 00:14:28.970
1167. Wow. A small

374
00:14:28.970 --> 00:14:31.250
outburst on the 15th, which I've seen no

375
00:14:31.250 --> 00:14:33.890
reports of, that was a 1633 dust stream.

376
00:14:34.210 --> 00:14:36.770
But then a couple of hours after the forecast

377
00:14:36.770 --> 00:14:39.490
peak, which is tonight, Australia time, as

378
00:14:39.490 --> 00:14:41.170
we're recording at early hours of Tuesday

379
00:14:41.170 --> 00:14:43.930
morning, um, there is both a

380
00:14:43.930 --> 00:14:46.370
regular maximum but also a potential crossing

381
00:14:46.370 --> 00:14:49.250
of a couple of dust streams from 1699.

382
00:14:50.280 --> 00:14:52.280
Now none of these will really boost the rates

383
00:14:52.280 --> 00:14:54.920
above that 10 or 15 per hour, but there are

384
00:14:54.920 --> 00:14:57.800
really important tests for our models

385
00:14:57.800 --> 00:14:59.960
of how well we can predict where these dust

386
00:14:59.960 --> 00:15:02.280
streams will be and how dense they'll be. And

387
00:15:02.280 --> 00:15:03.880
it's not the most straightforward process.

388
00:15:04.040 --> 00:15:06.840
People who are doing this research have to

389
00:15:07.080 --> 00:15:08.880
track the comet's orbit back in time, which

390
00:15:08.880 --> 00:15:10.560
is where ancient comet observations are

391
00:15:10.560 --> 00:15:12.480
really useful, old observations of the comet.

392
00:15:12.480 --> 00:15:15.040
To pinpoint it, they need to then have a

393
00:15:15.040 --> 00:15:17.560
model of how the dust grains are ejected from

394
00:15:17.560 --> 00:15:20.330
the comet at each perihelion, how the non

395
00:15:20.330 --> 00:15:22.570
gravitational forces like radiation pressure,

396
00:15:22.570 --> 00:15:24.730
the Ponting Robertson effect, all these

397
00:15:24.730 --> 00:15:26.770
effects push the dust grains around and they

398
00:15:26.770 --> 00:15:28.970
have to then run them forward in time with

399
00:15:28.970 --> 00:15:30.730
the gravity of all the planets and all those

400
00:15:30.730 --> 00:15:32.610
non gravitational forces to figure out where

401
00:15:32.610 --> 00:15:35.090
they cluster near the Earth's orbit. So it's

402
00:15:35.090 --> 00:15:36.850
very complex modeling and anything we can do

403
00:15:36.850 --> 00:15:38.730
to ground truth that by getting observations

404
00:15:38.730 --> 00:15:41.210
of the meteor shower are really useful. So if

405
00:15:41.210 --> 00:15:42.890
we see an uptick and we see the rates are a

406
00:15:42.890 --> 00:15:44.650
bit higher or a bit lower than predicted,

407
00:15:45.300 --> 00:15:47.660
that allows us to refine the models so that

408
00:15:47.660 --> 00:15:50.060
when it comes to the bigger potential

409
00:15:50.060 --> 00:15:52.300
numbers, which next year could be a slightly

410
00:15:52.300 --> 00:15:54.140
better year, potentially up to 30 or 40 an

411
00:15:54.140 --> 00:15:55.580
hour depending on some of the models, for

412
00:15:55.580 --> 00:15:58.180
example, we can have more confidence in that.

413
00:15:58.500 --> 00:15:59.820
So that's really what's going on with the

414
00:15:59.820 --> 00:16:02.460
Lenith. So while I get grumpy about the

415
00:16:02.460 --> 00:16:04.340
stories, encouraging people who are not fans

416
00:16:04.340 --> 00:16:06.180
of astronomy normally to go out and spend

417
00:16:06.180 --> 00:16:07.940
their nights out in the Northern Hemisphere,

418
00:16:07.940 --> 00:16:10.140
cold in the Southern Hemisphere, heat and

419
00:16:10.140 --> 00:16:11.780
humidity and rain that we're getting at the

420
00:16:11.780 --> 00:16:14.220
minute. I get a bit grumpy because this isn't

421
00:16:14.220 --> 00:16:16.980
the shower to watch for that. If you're not a

422
00:16:16.980 --> 00:16:19.980
mad keen meteor fan anyway, this isn't

423
00:16:19.980 --> 00:16:21.980
the one to watch. What you should do is wait

424
00:16:21.980 --> 00:16:23.500
a month and look at the Geminis, which we can

425
00:16:23.500 --> 00:16:24.820
talk about in just a little minute.

426
00:16:25.300 --> 00:16:28.219
Andrew Dunkley: Yes. Uh, and we might as well just jump

427
00:16:28.219 --> 00:16:30.340
straight into that because, uh, they're due

428
00:16:30.660 --> 00:16:31.540
mid December.

429
00:16:32.580 --> 00:16:33.060
Jonti Horner: Yes.

430
00:16:33.700 --> 00:16:36.620
So, you know, I always love meteor showers.

431
00:16:36.620 --> 00:16:38.700
Meteor showers are part of what hooked me in

432
00:16:38.700 --> 00:16:40.980
and kept me in as a kid. So I've always got a

433
00:16:40.980 --> 00:16:43.000
soft spot in my heart for them. And back in

434
00:16:43.000 --> 00:16:45.720
the 90s, we had. The

435
00:16:45.720 --> 00:16:48.160
Perseids were clearly the strongest meteor

436
00:16:48.160 --> 00:16:49.280
shower of the year from the Northern

437
00:16:49.280 --> 00:16:51.240
Hemisphere. And that's a shower that's active

438
00:16:51.240 --> 00:16:53.280
in August. And the caveat is we don't really

439
00:16:53.280 --> 00:16:55.120
see that very well in the Southern

440
00:16:55.120 --> 00:16:57.200
Hemisphere. Yeah. We then have the

441
00:16:57.200 --> 00:17:00.120
Quadrantids at the start of January, which

442
00:17:00.120 --> 00:17:01.400
are, uh, one of the year's best three

443
00:17:01.400 --> 00:17:03.200
showers, but a very hit and miss. They're

444
00:17:03.200 --> 00:17:05.680
only at their peak for a very short period of

445
00:17:05.680 --> 00:17:07.400
time, just a few hours. And, um, they are

446
00:17:07.400 --> 00:17:09.320
again very much a Northern Hemisphere only

447
00:17:09.320 --> 00:17:11.770
shower. Then we have the Geminids. And the

448
00:17:11.770 --> 00:17:13.810
Geminids were first seen, I think, in the

449
00:17:13.810 --> 00:17:16.570
late 1800s, and

450
00:17:16.570 --> 00:17:19.450
ever since they've been getting stronger. So

451
00:17:19.450 --> 00:17:20.850
they started off as one of the year's

452
00:17:20.850 --> 00:17:22.210
moderate showers and they've grown in

453
00:17:22.210 --> 00:17:25.010
strength. And by the early 1990s when I was

454
00:17:25.010 --> 00:17:26.850
watching them, they had a zenithal hourly

455
00:17:26.850 --> 00:17:28.890
rate, the ZHR, of about 100 per hour.

456
00:17:29.690 --> 00:17:32.410
That's now up to 150 an hour. And they are

457
00:17:32.810 --> 00:17:35.250
undisputedly the king of the meteor showers

458
00:17:35.250 --> 00:17:37.570
in a typical year, unless we get like a

459
00:17:37.570 --> 00:17:39.650
meteor storm from one of the episodic showers

460
00:17:39.650 --> 00:17:41.680
like the Leonids or the Jacobeenids or the,

461
00:17:42.310 --> 00:17:44.710
or something like this in a normal year.

462
00:17:45.190 --> 00:17:47.030
The Geminids of the King, and they're very,

463
00:17:47.030 --> 00:17:49.670
very reliable. They're also,

464
00:17:50.430 --> 00:17:52.510
um, the only one of those big three meteor

465
00:17:52.510 --> 00:17:54.750
showers that is easily seen from the Southern

466
00:17:54.750 --> 00:17:56.270
Hemisphere. The Northern Hemisphere still

467
00:17:56.270 --> 00:17:58.390
gets the best views, undeniably because the

468
00:17:58.390 --> 00:18:00.390
radiant for the Geminids is north of the

469
00:18:00.470 --> 00:18:03.430
equator. So easier to get high in the sky

470
00:18:03.750 --> 00:18:06.310
from northern latitudes, rises earlier,

471
00:18:06.390 --> 00:18:09.260
stays up longer, all the rest of it. But

472
00:18:09.260 --> 00:18:11.740
even from Australia and other Southern

473
00:18:11.740 --> 00:18:13.700
Hemisphere locations, the Geminids are really

474
00:18:13.700 --> 00:18:16.340
good. They're at the peak on the nights of

475
00:18:16.340 --> 00:18:18.940
the 13th and the 14th of

476
00:18:18.940 --> 00:18:21.340
December, the night of the 13th into the

477
00:18:21.340 --> 00:18:23.500
morning of the 14th is the best for most

478
00:18:23.500 --> 00:18:25.140
people. For us here in Australia because

479
00:18:25.140 --> 00:18:27.860
we're so far ahead on the clocks the rates

480
00:18:27.860 --> 00:18:30.860
will be building to their peak before dawn on

481
00:18:30.860 --> 00:18:32.780
the morning of the 14th, that's night of the

482
00:18:32.780 --> 00:18:35.440
13th and then falling away from the peak very

483
00:18:35.440 --> 00:18:37.480
slowly on the evening of the 14th. The peaks

484
00:18:37.480 --> 00:18:40.120
during our daylight hours but the Gemnids

485
00:18:40.120 --> 00:18:42.400
have quite a broad peak as well so they're

486
00:18:42.400 --> 00:18:44.640
worth watching for a couple of days either

487
00:18:44.640 --> 00:18:47.480
side of maximum. Um, well worth going out,

488
00:18:47.480 --> 00:18:49.719
camping, getting away from street lights,

489
00:18:49.719 --> 00:18:52.440
getting to a dark site. If you're at uh, my

490
00:18:52.440 --> 00:18:54.320
latitude in Southeast Queensland you'll see

491
00:18:54.320 --> 00:18:56.600
the first gemnids from about 9, 30, 10 o'

492
00:18:56.600 --> 00:18:58.240
clock at night. But the best rates are later

493
00:18:58.240 --> 00:19:00.750
in the evening. The peak rates anywhere on

494
00:19:00.750 --> 00:19:03.270
the planet are about 2am or

495
00:19:03.270 --> 00:19:05.390
3am if you've got daylight savings like the

496
00:19:05.390 --> 00:19:07.030
people in the southern states of Australia,

497
00:19:07.350 --> 00:19:08.830
you move your clocks forward an hour, you

498
00:19:08.830 --> 00:19:11.550
move everything forward an hour. But the

499
00:19:11.550 --> 00:19:13.550
further north you are on the planet the

500
00:19:13.550 --> 00:19:15.190
earlier you can start watching. And for me

501
00:19:15.190 --> 00:19:17.990
growing up in the UK the radiant was above

502
00:19:17.990 --> 00:19:20.230
the horizon pretty much after sunset and was

503
00:19:20.230 --> 00:19:22.270
above the horizon all night. So even as a 12

504
00:19:22.270 --> 00:19:24.470
year old when my parents were grumbling that

505
00:19:24.470 --> 00:19:26.110
I should do my homework and I needed an early

506
00:19:26.110 --> 00:19:28.300
night school the next morning I could still

507
00:19:28.300 --> 00:19:30.260
get a decent show before I went to sleep.

508
00:19:31.060 --> 00:19:32.580
Nowadays if I was still in the northern

509
00:19:32.580 --> 00:19:34.540
hemisphere I'd be able to stay up all night

510
00:19:34.540 --> 00:19:36.260
because I'm a grown up and I can pick what I

511
00:19:36.260 --> 00:19:38.220
do but it will be cold and miserable so I

512
00:19:38.220 --> 00:19:40.740
might not do that. But it is a global

513
00:19:40.740 --> 00:19:42.540
opportunity to see a really good meteor

514
00:19:42.540 --> 00:19:43.870
shower and they are the best one of the uh

515
00:19:43.900 --> 00:19:45.740
year. So yeah, book your camping, book your

516
00:19:45.740 --> 00:19:48.460
holidays, find a dark site and don't blame me

517
00:19:48.460 --> 00:19:49.060
for the weather.

518
00:19:49.220 --> 00:19:51.900
Andrew Dunkley: Yes, yes, you can never do much about that.

519
00:19:51.900 --> 00:19:53.460
You just got to keep your fingers crossed.

520
00:19:53.460 --> 00:19:56.340
But uh, yeah a um, couple of meteor

521
00:19:56.340 --> 00:19:58.180
showers to keep an eye out for the Leonids

522
00:19:58.180 --> 00:20:00.960
happening as we speak Ish and the

523
00:20:00.960 --> 00:20:03.920
Geminids in mid December. Uh, you can look

524
00:20:03.920 --> 00:20:05.680
up the times and dates and

525
00:20:06.320 --> 00:20:09.160
etc uh online. This is

526
00:20:09.160 --> 00:20:12.040
Space Nuts with Andrew Dunkley and Jonti

527
00:20:12.040 --> 00:20:12.640
Horner.

528
00:20:15.120 --> 00:20:16.880
Jonti Horner: Roger, you're allowed to start here also

529
00:20:16.960 --> 00:20:18.080
Space Nuts.

530
00:20:18.160 --> 00:20:20.640
Andrew Dunkley: Now this, this uh, is a great story. Uh the

531
00:20:20.640 --> 00:20:23.040
Mars Escapade mission has

532
00:20:23.440 --> 00:20:26.160
lifted off successfully and this uh, is a

533
00:20:26.160 --> 00:20:27.480
good story for a number of reasons.

534
00:20:27.480 --> 00:20:30.110
Jonti Horner: In fact Jonti, it is. This is one where I

535
00:20:30.110 --> 00:20:31.470
feel like I'm going to be jumping off in

536
00:20:31.470 --> 00:20:32.990
several directions all at once. So it's

537
00:20:32.990 --> 00:20:34.910
almost like three mini segments in a way.

538
00:20:34.910 --> 00:20:35.470
Andrew Dunkley: Yeah.

539
00:20:36.190 --> 00:20:39.070
Jonti Horner: We spoke last week about the US shutdown and

540
00:20:39.070 --> 00:20:41.750
um, the issues it was causing for airspace

541
00:20:41.750 --> 00:20:44.710
over the US and um, the resulting ban on any

542
00:20:44.710 --> 00:20:47.270
rocket launchers other than between 10pm and

543
00:20:47.270 --> 00:20:49.710
6am and of course, fairly quickly after we

544
00:20:49.710 --> 00:20:52.550
talked about it, the shutdown was finally

545
00:20:52.550 --> 00:20:55.250
sorted and agreed and fixed. My

546
00:20:55.250 --> 00:20:56.770
understanding is that now everybody's trying

547
00:20:56.770 --> 00:20:58.490
to get the wheels turning on the bus again,

548
00:20:58.490 --> 00:21:00.330
so trying to get everything back into action.

549
00:21:01.050 --> 00:21:03.210
But that air traffic control

550
00:21:03.290 --> 00:21:06.050
restriction was still in space because it

551
00:21:06.050 --> 00:21:08.650
takes time to ramp things back up. This was

552
00:21:08.650 --> 00:21:10.930
relevant for spaceflight, particularly

553
00:21:10.930 --> 00:21:13.570
because of this NASA mission. Now, NASA has

554
00:21:13.570 --> 00:21:16.010
been shut down since the 1st of October, but

555
00:21:16.010 --> 00:21:18.530
fortunately this mission was already out of

556
00:21:18.530 --> 00:21:20.730
their hands in the hands of the launch

557
00:21:20.730 --> 00:21:22.950
provider. So the shutdown wasn't going to

558
00:21:22.950 --> 00:21:24.910
stop it, but where it could delay it was that

559
00:21:24.910 --> 00:21:26.790
the rocket needed to launch in daylight hours

560
00:21:27.110 --> 00:21:28.910
to be point for the Earth to be pointing in

561
00:21:28.910 --> 00:21:31.430
the right direction. Yeah. And so

562
00:21:31.670 --> 00:21:34.350
with the shutdown happening, um, they were on

563
00:21:34.350 --> 00:21:36.190
dodgy ground. They were hoping to launch just

564
00:21:36.190 --> 00:21:37.910
before the shutdown came in, but that launch

565
00:21:37.910 --> 00:21:40.350
got scrubbed. Then they got a waiver to

566
00:21:40.350 --> 00:21:42.070
launch during daylight hours because of

567
00:21:42.070 --> 00:21:44.270
special exemption from Florida. And that

568
00:21:44.270 --> 00:21:46.230
launch got scrubbed. But it finally managed

569
00:21:46.230 --> 00:21:49.200
to launch on Friday. This

570
00:21:49.200 --> 00:21:51.800
was launched by the commercial provider Blue

571
00:21:51.800 --> 00:21:54.120
Origin, whose new Glenn rocket put the thing

572
00:21:54.120 --> 00:21:56.680
up into space. And, um, it was a

573
00:21:56.680 --> 00:21:59.320
noteworthy launch for Blue Origin here

574
00:21:59.320 --> 00:22:00.680
because, hey, look, they've launched

575
00:22:00.680 --> 00:22:03.040
something that is going beyond the Earth Moon

576
00:22:03.040 --> 00:22:04.600
system. That's going to Mars. I mean, that's

577
00:22:04.600 --> 00:22:07.520
really cool. Anyway. But also their new Glenn

578
00:22:07.520 --> 00:22:10.400
rocket, the first stage, the lower stage, a

579
00:22:10.400 --> 00:22:11.880
big chunky thing that does a lot of the work

580
00:22:11.880 --> 00:22:13.730
to get you most of the way out of the

581
00:22:13.730 --> 00:22:16.210
atmosphere. Once that had detached from the

582
00:22:16.210 --> 00:22:18.330
second stage, it plummeted back down towards

583
00:22:18.330 --> 00:22:21.210
the Earth. And a couple of minutes after that

584
00:22:21.210 --> 00:22:23.210
stage separation, it turned its engines back

585
00:22:23.210 --> 00:22:25.850
on, stood up on its tail and landed safely

586
00:22:26.090 --> 00:22:28.650
on a barge in the ocean called Jaclyb.

587
00:22:29.370 --> 00:22:31.410
Now, we're kind of used to SpaceX managing

588
00:22:31.410 --> 00:22:33.370
this. They've been doing this for a while.

589
00:22:33.770 --> 00:22:36.330
But that ability to land and, um, recover

590
00:22:36.330 --> 00:22:39.100
your boosters to reuse them is actually

591
00:22:39.100 --> 00:22:41.900
really, really important. It's one of these

592
00:22:41.900 --> 00:22:44.820
things that allows you to reuse your boosters

593
00:22:45.220 --> 00:22:48.100
and so therefore by reusing them, you

594
00:22:48.100 --> 00:22:51.100
reduce the cost of future launches, which is

595
00:22:51.100 --> 00:22:52.900
part of what makes commercial spaceflight

596
00:22:52.900 --> 00:22:55.620
feasible. And, um, this is only the second

597
00:22:55.700 --> 00:22:57.740
company ever to manage this kind of Soft

598
00:22:57.740 --> 00:23:00.100
landing, safe landing type process

599
00:23:00.980 --> 00:23:02.540
M. So it's really remarkable that they

600
00:23:02.540 --> 00:23:04.580
actually achieved it. There's some fabulous

601
00:23:04.580 --> 00:23:06.420
videos out there. People are really thrilled

602
00:23:06.420 --> 00:23:07.910
watching these things happen. And it's a

603
00:23:08.380 --> 00:23:10.460
fabulous technological achievement. So it's a

604
00:23:10.540 --> 00:23:12.860
plus one and a tick for Blue Origin. They're

605
00:23:12.940 --> 00:23:14.780
very pleased with their role on this

606
00:23:15.500 --> 00:23:17.620
escapade itself is really interesting.

607
00:23:17.620 --> 00:23:19.380
It's launching out of sequence. Normally we

608
00:23:19.380 --> 00:23:22.300
get launchers to Mars in a big batch every 26

609
00:23:22.300 --> 00:23:25.020
months or so. And the reason for that is

610
00:23:25.020 --> 00:23:27.600
that Mars and the Earth move, uh,

611
00:23:27.820 --> 00:23:29.540
around the sun, um, with periods that are

612
00:23:29.540 --> 00:23:32.100
similar enough that Mars is closest to the

613
00:23:32.100 --> 00:23:33.980
Earth every 26 months or so.

614
00:23:35.130 --> 00:23:36.730
Now, if you want to get the cheapest,

615
00:23:36.730 --> 00:23:39.210
quickest flight to Mars, you don't launch

616
00:23:39.210 --> 00:23:40.650
when the Earth's on the opposite side of the

617
00:23:40.650 --> 00:23:42.130
sun to Mars because that means you've got to

618
00:23:42.130 --> 00:23:44.210
go the long way around. So people tend to

619
00:23:44.210 --> 00:23:45.890
wait for the launch window when they can do

620
00:23:45.890 --> 00:23:48.290
the shortest, quickest trip. And Instead of

621
00:23:48.290 --> 00:23:51.010
taking 12 or 18 months to get there, they can

622
00:23:51.010 --> 00:23:52.970
get there within six months and it's all nice

623
00:23:52.970 --> 00:23:55.090
and easy and cruisy. And the next launch

624
00:23:55.090 --> 00:23:57.170
window doesn't actually open until about this

625
00:23:57.170 --> 00:23:58.810
next time next year.

626
00:23:59.780 --> 00:24:01.940
Escapade, though, has an interesting launch

627
00:24:01.940 --> 00:24:03.860
window in that it's not launching directly to

628
00:24:03.860 --> 00:24:06.220
Mars, it's doing something different. It's

629
00:24:06.220 --> 00:24:08.860
going to launch out to the second Lagrange

630
00:24:08.860 --> 00:24:10.500
point, the Sun, Earth. Lagrange point number

631
00:24:10.500 --> 00:24:12.780
two, which is beyond the Earth and its orbit

632
00:24:12.780 --> 00:24:14.660
between the orbits of Earth and Mars, about a

633
00:24:14.660 --> 00:24:16.300
million kilometers further from the sun than

634
00:24:16.300 --> 00:24:18.620
we are. And the Tiffany is where a few space

635
00:24:18.620 --> 00:24:20.220
observatories like the James Webb Space

636
00:24:20.220 --> 00:24:22.420
Telescope are hanging out, spending their

637
00:24:22.420 --> 00:24:25.260
time. Escapade is going to hang

638
00:24:25.260 --> 00:24:27.590
around there for about 12 months then, then

639
00:24:27.590 --> 00:24:29.470
this time next year, as the launch window to

640
00:24:29.470 --> 00:24:31.710
Mars opens, it's going to drop back out of

641
00:24:31.710 --> 00:24:33.380
the Lagrange point, swing towards the Earth,

642
00:24:33.380 --> 00:24:35.640
uh, get a gravity assist from the Earth, uh,

643
00:24:35.640 --> 00:24:37.830
and boost off towards Mars. Getting there in

644
00:24:37.830 --> 00:24:39.630
about September 2027,

645
00:24:40.670 --> 00:24:42.750
is that right? September 2027. That sounds

646
00:24:42.750 --> 00:24:45.070
about right, yes. Um, so

647
00:24:45.550 --> 00:24:47.830
it's going to take the long way around. But

648
00:24:47.830 --> 00:24:50.270
this is a very economic way of doing things

649
00:24:50.270 --> 00:24:53.270
and it also opens up the possibility of not

650
00:24:53.270 --> 00:24:54.990
having to wait for that launch window and

651
00:24:54.990 --> 00:24:56.470
being at the whims of the weather and stuff.

652
00:24:56.470 --> 00:24:58.790
You know, the worst case scenario is you're

653
00:24:58.790 --> 00:25:00.990
launching from one of these launch platform

654
00:25:00.990 --> 00:25:03.030
areas where they get cyclones, they get

655
00:25:03.030 --> 00:25:05.910
hurricanes or typhoons, and, um, your

656
00:25:05.910 --> 00:25:07.670
launch is scrubbed. But the launch site is

657
00:25:07.670 --> 00:25:09.270
then damaged and by the time it's repaired,

658
00:25:09.270 --> 00:25:10.670
the launch windows close and you've got to

659
00:25:10.670 --> 00:25:12.390
wait 26 months and that's not good for

660
00:25:12.390 --> 00:25:14.590
anybody, um, particularly the staff who are

661
00:25:14.590 --> 00:25:16.670
waiting to wait on the mission. So if you now

662
00:25:16.670 --> 00:25:18.230
have something where you can launch missions

663
00:25:18.230 --> 00:25:21.190
to Mars at almost any time and they can

664
00:25:21.190 --> 00:25:23.750
just go into a holding orbit, do some extra

665
00:25:23.750 --> 00:25:25.230
work while they're there because nobody likes

666
00:25:25.230 --> 00:25:27.540
to be idle, um, and then boosts on off to

667
00:25:27.540 --> 00:25:29.660
Mars, that's got really interesting

668
00:25:29.660 --> 00:25:32.180
implications for the future of Mars

669
00:25:32.180 --> 00:25:33.620
exploration in particular, but also

670
00:25:33.620 --> 00:25:36.620
potentially exploring the other planets in

671
00:25:36.620 --> 00:25:39.380
the solar system. As the spacecraft goes out

672
00:25:39.380 --> 00:25:41.740
there, whilst it hangs around at the L2

673
00:25:41.740 --> 00:25:43.900
point, it will be earning its keep. It'll be

674
00:25:43.900 --> 00:25:45.940
doing observations of the solar wind and

675
00:25:45.940 --> 00:25:47.940
measurements of that which will serve the

676
00:25:47.940 --> 00:25:49.580
purpose of testing all the equipment on the

677
00:25:49.580 --> 00:25:52.140
spacecraft and also send back extra

678
00:25:52.140 --> 00:25:54.830
awesome data, uh, that scientists who study

679
00:25:54.830 --> 00:25:57.350
space weather can use. And then it'll drop

680
00:25:57.350 --> 00:25:59.750
and boost off towards Mars. So that's all

681
00:25:59.750 --> 00:26:02.590
very, very cool. Another aspect of this

682
00:26:02.590 --> 00:26:04.990
that's really awesome is that it's a

683
00:26:04.990 --> 00:26:06.750
commercially built spacecraft. So it was

684
00:26:06.750 --> 00:26:08.870
built by Rocket Lab, who are a big NASA

685
00:26:08.870 --> 00:26:11.350
partner. And so you've got an entire mission

686
00:26:11.350 --> 00:26:13.528
to Mars for about US$80

687
00:26:13.692 --> 00:26:16.390
million. And uh, that includes about $7

688
00:26:16.390 --> 00:26:18.750
million worth of delays because NASA didn't

689
00:26:18.750 --> 00:26:20.860
want to launch until Blue Origin had

690
00:26:20.860 --> 00:26:22.420
confirmed that they could launch a rocket and

691
00:26:22.420 --> 00:26:25.380
get it back safely. So this is a mission

692
00:26:25.380 --> 00:26:27.558
to Mars for about US$80

693
00:26:27.722 --> 00:26:29.980
million, which is

694
00:26:30.140 --> 00:26:32.380
hugely cheaper than previous

695
00:26:32.700 --> 00:26:35.420
Mars missions. So we're seeing again,

696
00:26:35.579 --> 00:26:37.300
not just from the launch, but actually from

697
00:26:37.300 --> 00:26:39.860
the construction of the spacecraft here, the

698
00:26:39.860 --> 00:26:41.860
real benefit you get when you finally get to

699
00:26:41.860 --> 00:26:43.980
the point where you can commercialize space

700
00:26:44.300 --> 00:26:47.150
travel and space flight. Because by

701
00:26:47.150 --> 00:26:48.910
bringing in commercial partners, by being

702
00:26:48.910 --> 00:26:51.230
able to build things using off the shelf

703
00:26:51.230 --> 00:26:52.990
components, things like that, you bring the

704
00:26:52.990 --> 00:26:55.790
costs usually down and that enables far more

705
00:26:55.790 --> 00:26:58.590
science. So that is really exciting and

706
00:26:58.590 --> 00:27:00.110
reassuring to me as well the fact we'll be

707
00:27:00.110 --> 00:27:01.590
able to do missions like this in the future

708
00:27:02.070 --> 00:27:04.670
for cheaper. And uh, the final bit of course

709
00:27:04.670 --> 00:27:06.070
is what these things are actually going to

710
00:27:06.070 --> 00:27:08.030
do. There's two spacecraft called Blue and

711
00:27:08.030 --> 00:27:10.390
Gold who are going to fly in formation when

712
00:27:10.390 --> 00:27:12.070
they get to Mars, they're going to gradually

713
00:27:12.070 --> 00:27:13.750
lower their orbits until they're moving on

714
00:27:13.750 --> 00:27:16.520
identical orbits, one leading the other, a

715
00:27:16.520 --> 00:27:18.080
bit like ring a ring of roses or something,

716
00:27:18.080 --> 00:27:19.800
one going around in front of the other one.

717
00:27:20.120 --> 00:27:22.280
And they're going to spend about 11 months

718
00:27:22.600 --> 00:27:25.000
studying how Mars's atmosphere

719
00:27:25.240 --> 00:27:28.120
responds to the solar wind, really trying

720
00:27:28.120 --> 00:27:30.960
to unpick um, what happens in

721
00:27:30.960 --> 00:27:32.720
terms of the bleeding away of Mars's

722
00:27:32.720 --> 00:27:35.000
atmosphere to help us try and get a handle on

723
00:27:35.000 --> 00:27:37.800
why Mars is no longer the warm, wet

724
00:27:37.800 --> 00:27:39.520
Mars that it once was, with a thick

725
00:27:39.520 --> 00:27:42.260
atmosphere and abundant oceans. Yeah, trying

726
00:27:42.260 --> 00:27:43.900
to get a feel on those processes that

727
00:27:43.900 --> 00:27:45.740
stripped the atmosphere away to leave it the

728
00:27:45.740 --> 00:27:48.100
kind of arid husk it is today. So that's

729
00:27:48.100 --> 00:27:49.700
going to be really cool science. So it's

730
00:27:49.860 --> 00:27:51.900
like, it's one of these stories where there's

731
00:27:51.900 --> 00:27:53.260
so many different aspects that are

732
00:27:53.260 --> 00:27:55.140
individually fascinating. It's hard to know

733
00:27:55.300 --> 00:27:56.980
where to look first, essentially.

734
00:27:57.060 --> 00:28:00.020
Andrew Dunkley: Oh yeah, this one's really exciting and it's,

735
00:28:00.030 --> 00:28:02.660
um, you know, it's going to be in the news

736
00:28:03.300 --> 00:28:06.180
over the next few years. And those,

737
00:28:06.180 --> 00:28:08.500
those mysteries that have always surrounded

738
00:28:08.500 --> 00:28:10.900
Mars, we can get answers to those. That will

739
00:28:10.900 --> 00:28:13.260
be really valuable information. But it'll

740
00:28:13.260 --> 00:28:15.100
also close the book on a couple of things

741
00:28:15.100 --> 00:28:18.020
that we've really been trying to figure out

742
00:28:18.020 --> 00:28:20.660
for a very, very long time. Because we know

743
00:28:20.900 --> 00:28:23.460
historically Mars was warm and wet and

744
00:28:23.660 --> 00:28:26.420
uh, may, uh, have had life.

745
00:28:28.020 --> 00:28:30.940
What, um, happened? Um, well, there's

746
00:28:30.940 --> 00:28:33.220
stuff we do know, but there's still

747
00:28:33.220 --> 00:28:36.190
mysteries. Um, the, uh, I'm just reading here

748
00:28:36.190 --> 00:28:38.800
the, uh, the green auroras that, uh,

749
00:28:38.800 --> 00:28:41.150
Mars has, they can't figure that one out. So

750
00:28:41.150 --> 00:28:42.750
hopefully they'll have an answer for that as

751
00:28:42.750 --> 00:28:45.230
well. So much more, plenty to learn.

752
00:28:45.950 --> 00:28:48.550
Jonti Horner: It's also got a really expanded scope to that

753
00:28:48.550 --> 00:28:50.590
and that we're going to be in a position to

754
00:28:50.590 --> 00:28:53.030
start actively searching for evidence of life

755
00:28:53.030 --> 00:28:54.830
on planets beyond the solar system fairly

756
00:28:54.830 --> 00:28:56.870
soon. I mean, we are trying already. Yeah.

757
00:28:56.870 --> 00:28:58.550
But as our technology gets better, we'll get

758
00:28:58.550 --> 00:29:01.030
better and better, uh, looking at these

759
00:29:01.030 --> 00:29:02.630
planets we find around other stars to look

760
00:29:02.630 --> 00:29:04.350
for evidence of life. And one of the big

761
00:29:04.350 --> 00:29:06.190
questions, particularly when it comes to Plan

762
00:29:06.890 --> 00:29:08.930
M dwarf stars, the little tiny red dwarf

763
00:29:08.930 --> 00:29:11.530
stars, is whether planets could actually

764
00:29:11.770 --> 00:29:13.650
hold onto their atmospheres for long enough

765
00:29:13.650 --> 00:29:15.610
for life to get established and to thrive.

766
00:29:16.010 --> 00:29:17.610
And that's kind of backed up. If you look at

767
00:29:17.610 --> 00:29:20.010
the story of the planets around Trappist 1,

768
00:29:20.650 --> 00:29:22.690
there was huge excitement about those from

769
00:29:22.690 --> 00:29:24.410
people who were overblowing them as being

770
00:29:24.410 --> 00:29:25.970
potentially the best targets for the search

771
00:29:25.970 --> 00:29:28.970
for life elsewhere. Um, when people looked at

772
00:29:28.970 --> 00:29:31.490
them M with James Webb, they don't have

773
00:29:31.490 --> 00:29:33.130
atmospheres, which is kind of a problem if

774
00:29:33.130 --> 00:29:34.570
you want to have liquid water on the surface

775
00:29:34.570 --> 00:29:36.250
of a planet. Not having an atmosphere is a

776
00:29:36.250 --> 00:29:39.180
bit of a killer. So this escapade

777
00:29:39.180 --> 00:29:41.500
mission, by telling us more about the

778
00:29:41.500 --> 00:29:44.380
process, um, by which Mars lost

779
00:29:44.380 --> 00:29:47.380
its atmosphere and lost its oceans, that

780
00:29:47.380 --> 00:29:49.060
data is not just helpful in putting the Earth

781
00:29:49.060 --> 00:29:50.780
into context. It's not just helpful in

782
00:29:50.780 --> 00:29:52.500
looking at the history of life on Mars

783
00:29:52.500 --> 00:29:55.260
potentially, but it's also really useful data

784
00:29:55.660 --> 00:29:57.660
for, as we look at planets around other stars

785
00:29:57.660 --> 00:29:59.060
and try and figure out which are the best

786
00:29:59.060 --> 00:30:01.420
targets for us to look at from the point of

787
00:30:01.420 --> 00:30:03.580
view of the search for life. It will

788
00:30:03.580 --> 00:30:05.740
hopefully kind of help us figure out whether

789
00:30:05.740 --> 00:30:07.740
red dwarf planets are viable or whether we

790
00:30:07.740 --> 00:30:10.260
should just write off planets around stars

791
00:30:10.260 --> 00:30:13.020
smaller than a certain mass entirely, when

792
00:30:13.020 --> 00:30:15.420
we're going to have very limited facility to

793
00:30:15.420 --> 00:30:17.460
study planets and to look for life on them.

794
00:30:17.700 --> 00:30:20.020
So it's a mission with a scope beyond just a

795
00:30:20.020 --> 00:30:20.980
solar system, I think.

796
00:30:21.300 --> 00:30:22.980
Andrew Dunkley: Yeah, I'm not going to wait for the results.

797
00:30:22.980 --> 00:30:25.460
I've already decided in my new sci fi novel

798
00:30:25.460 --> 00:30:28.140
that the planet in question does have an

799
00:30:28.140 --> 00:30:30.380
atmosphere and it is orbiting a red dwarf.

800
00:30:30.380 --> 00:30:32.580
So, yes, all bets, all bets are off.

801
00:30:34.260 --> 00:30:35.660
But, uh, yeah, it's going to be a great

802
00:30:35.660 --> 00:30:38.340
mission. So we'll, uh, keep an eye on

803
00:30:38.340 --> 00:30:41.010
everything going on with, uh, that, uh,

804
00:30:41.010 --> 00:30:42.820
mission to Mars and beyond.

805
00:30:43.270 --> 00:30:46.100
Uh, let's move on to our

806
00:30:46.100 --> 00:30:48.500
next story, Jonti, and this involves

807
00:30:49.220 --> 00:30:52.180
China, the Tiangong Space Station.

808
00:30:52.690 --> 00:30:55.580
Um, people go to and from that on a fairly

809
00:30:55.580 --> 00:30:57.540
regular basis. We don't hear much about it,

810
00:30:57.540 --> 00:30:59.460
but we're hearing about it now because

811
00:31:00.960 --> 00:31:02.400
there's a few people stranded.

812
00:31:02.400 --> 00:31:04.280
Jonti Horner: Yes, and it's happened again, of course. We

813
00:31:04.280 --> 00:31:06.880
had this back in 2024 with the International

814
00:31:07.040 --> 00:31:09.480
Space Station and the NASA astronauts, Butch

815
00:31:09.480 --> 00:31:12.000
and Sonny, who were up there for, uh, an

816
00:31:12.000 --> 00:31:14.640
extended holiday, um, because

817
00:31:15.040 --> 00:31:16.760
they were stranded there because of the

818
00:31:16.760 --> 00:31:18.800
problems with getting a vehicle up there to

819
00:31:18.800 --> 00:31:19.920
bring them home. Effectively,

820
00:31:21.520 --> 00:31:23.120
it's almost a little bit like history

821
00:31:23.120 --> 00:31:25.280
repeating itself. So the backstory here is

822
00:31:25.280 --> 00:31:27.560
that the new crew on the Chinese space

823
00:31:27.560 --> 00:31:30.120
station Tiangong arrived relatively recently

824
00:31:30.520 --> 00:31:32.840
on the spacecraft, on the

825
00:31:33.720 --> 00:31:36.200
delivery vehicle, I guess, on the bus called

826
00:31:36.200 --> 00:31:39.200
shenzhou21. Yeah, and normally that

827
00:31:39.200 --> 00:31:41.160
would stay there to bring them back home

828
00:31:41.160 --> 00:31:43.039
again. And, uh, the previous crew would go

829
00:31:43.039 --> 00:31:45.000
home on their spacecraft, which was Shenzhou

830
00:31:45.000 --> 00:31:48.000
20. But Shenzhou 20 was victim of

831
00:31:48.000 --> 00:31:50.880
a space debris strike and, um, was considered

832
00:31:50.880 --> 00:31:53.740
unfit to return. People harm. There

833
00:31:53.740 --> 00:31:55.420
were concerns that it wouldn't get back down

834
00:31:55.420 --> 00:31:57.500
in one piece, which is very similar, in fact

835
00:31:57.500 --> 00:32:00.420
to what happened in 2024. And so the crew who

836
00:32:00.420 --> 00:32:03.300
were on Tiangong got onto Shenzhou

837
00:32:03.300 --> 00:32:05.900
21, returned home. And that leaves the

838
00:32:05.900 --> 00:32:08.660
current crew kind of without a lifeboat,

839
00:32:08.660 --> 00:32:10.900
without a means to ride home safely.

840
00:32:11.380 --> 00:32:13.420
Andrew Dunkley: Yeah, it's sort of like taking someone else's

841
00:32:13.420 --> 00:32:14.220
taxi, isn't it?

842
00:32:14.220 --> 00:32:15.860
Jonti Horner: It is, pretty much. And so they've got to

843
00:32:15.860 --> 00:32:18.380
wait for the next taxi off the rank. Now the

844
00:32:18.380 --> 00:32:20.490
reason this is a bit shorter of a segment is

845
00:32:20.490 --> 00:32:23.410
uh, China are much more close lipped about

846
00:32:23.410 --> 00:32:25.170
what's happening. Particularly when a story's

847
00:32:25.170 --> 00:32:26.770
life and we've seen this with their moon

848
00:32:26.770 --> 00:32:28.970
missions and the Mars missions before, they

849
00:32:28.970 --> 00:32:30.130
don't tend to tell you much about them

850
00:32:30.130 --> 00:32:31.490
beforehand. They wait till they're

851
00:32:31.490 --> 00:32:34.090
successful, then they talk about them. Now

852
00:32:34.090 --> 00:32:36.290
there are space uh, experts who've been

853
00:32:36.290 --> 00:32:38.810
interviewed about this and the story is

854
00:32:38.810 --> 00:32:41.490
apparently that China will typically keep one

855
00:32:41.490 --> 00:32:43.610
of their Long March 2F rockets, their big

856
00:32:43.610 --> 00:32:46.370
rockets and a backup Shenzhou

857
00:32:46.370 --> 00:32:49.090
spacecraft in what, what has been described

858
00:32:49.090 --> 00:32:50.890
as a state of near readiness. In other words,

859
00:32:50.890 --> 00:32:53.530
it's not ready to go right now. But in theory

860
00:32:53.770 --> 00:32:55.560
they should be able to get the lifeboat, uh,

861
00:32:55.730 --> 00:32:57.850
up to Tiangong within about eight and a half

862
00:32:57.850 --> 00:33:00.290
days of realizing there's a problem, which is

863
00:33:00.290 --> 00:33:02.530
probably not hugely comforting to the people

864
00:33:02.530 --> 00:33:05.170
up there. But in reality eight and a half

865
00:33:05.170 --> 00:33:06.850
days is a hell of a lot quicker than we got

866
00:33:06.850 --> 00:33:09.490
Butcher and Sunnyback. Oh yeah. What Chinese

867
00:33:09.490 --> 00:33:11.410
officials have said is that they've said that

868
00:33:11.410 --> 00:33:14.050
Shenzhou 22, which is a next tax to go up

869
00:33:14.050 --> 00:33:16.570
there basically will be launched to Tiangong

870
00:33:16.570 --> 00:33:19.450
at an appropriate time in the future, which

871
00:33:19.450 --> 00:33:21.730
is fairly close mouth. But the likelihood is

872
00:33:21.730 --> 00:33:23.930
that uh, that will go up without a crew.

873
00:33:24.250 --> 00:33:26.490
It'll be an autonomous thing so that it can

874
00:33:26.490 --> 00:33:28.450
latch on and give these people a ride home

875
00:33:28.450 --> 00:33:30.930
when they're ready. So you know, hopefully

876
00:33:30.930 --> 00:33:33.730
they will get back on schedule and

877
00:33:33.730 --> 00:33:35.410
they'll certainly have the lifeboat there if

878
00:33:35.410 --> 00:33:37.650
they need it a lot more quickly than Butch

879
00:33:37.650 --> 00:33:39.930
and Sunny would with their extended stay and

880
00:33:39.930 --> 00:33:42.690
their long, long, unexpected fly in, fly out

881
00:33:42.690 --> 00:33:43.290
adventure.

882
00:33:43.770 --> 00:33:46.770
Andrew Dunkley: Yes, indeed. Uh, but it's also, it

883
00:33:46.770 --> 00:33:49.250
also underlines the risks that people take

884
00:33:49.250 --> 00:33:52.010
going into space. Uh, it is a hostile

885
00:33:52.010 --> 00:33:54.650
environment and it sounds very much like

886
00:33:54.980 --> 00:33:57.690
uh, the damage that they suffered on one of

887
00:33:57.690 --> 00:34:00.330
those shuttles was probably caused by

888
00:34:00.330 --> 00:34:02.770
something else we sent up there some time in

889
00:34:02.770 --> 00:34:03.210
the past.

890
00:34:03.290 --> 00:34:05.690
Jonti Horner: Yeah, um, this is going to be an ever greater

891
00:34:05.690 --> 00:34:07.810
risk the more stuff we put up there. Uh, I

892
00:34:07.810 --> 00:34:09.650
mean it goes back to the discussion we had

893
00:34:09.650 --> 00:34:12.340
about space elevators last week. But

894
00:34:12.740 --> 00:34:15.420
the more stuff we put up there, the more you

895
00:34:15.420 --> 00:34:18.140
have to learn to dodge if you are something

896
00:34:18.140 --> 00:34:20.500
that has people on board. Which probably

897
00:34:20.500 --> 00:34:22.740
doesn't bode all that well for the plans that

898
00:34:22.740 --> 00:34:24.540
we kept talking about a few years ago about

899
00:34:24.540 --> 00:34:27.180
possibly having space hotels up there and

900
00:34:27.180 --> 00:34:30.140
stuff like that. Because the space

901
00:34:30.140 --> 00:34:31.980
hotel industry is probably not going to be

902
00:34:31.980 --> 00:34:34.740
all that impressed with the growing Use of

903
00:34:34.740 --> 00:34:37.580
commercial space for Internet satellites and

904
00:34:37.580 --> 00:34:40.020
things like this. So there's really

905
00:34:40.020 --> 00:34:41.820
interesting challenges in our future. And

906
00:34:41.820 --> 00:34:43.460
this is just highlighting a problem that will

907
00:34:43.460 --> 00:34:46.060
become more and more significant in the years

908
00:34:46.060 --> 00:34:48.740
to come unless we get better legislation

909
00:34:48.740 --> 00:34:49.780
around the use of space.

910
00:34:51.300 --> 00:34:53.620
Andrew Dunkley: And the, um, the rules

911
00:34:54.420 --> 00:34:57.260
should consider, you know, cleaning up your

912
00:34:57.260 --> 00:35:00.180
own act. Uh, I know, I know. There is

913
00:35:00.180 --> 00:35:03.180
a code requiring you to, you know, look

914
00:35:03.180 --> 00:35:05.790
after your own stuff when it's been

915
00:35:05.950 --> 00:35:07.950
dealt with or you finished using it or

916
00:35:07.950 --> 00:35:10.350
whatever and deorbit it and burn it up. But

917
00:35:10.350 --> 00:35:12.030
that's another, that's creating another

918
00:35:12.030 --> 00:35:13.790
problem because all this stuff that burns up

919
00:35:13.790 --> 00:35:16.390
ends up staying in the upper atmosphere. And

920
00:35:16.390 --> 00:35:17.990
we don't know what that's going to do in the

921
00:35:17.990 --> 00:35:18.270
future.

922
00:35:18.350 --> 00:35:20.070
Jonti Horner: No, it's awfully complex. And I mean, the

923
00:35:20.070 --> 00:35:22.190
other thing is that whole thing about bring,

924
00:35:22.270 --> 00:35:24.350
bring stuff back into the atmosphere to

925
00:35:24.670 --> 00:35:27.350
declutter space is all well and good, but if

926
00:35:27.350 --> 00:35:29.230
a satellite gets smashed by a bit of space

927
00:35:29.230 --> 00:35:31.590
debris, you can't control where the debris

928
00:35:31.590 --> 00:35:34.350
goes. It isn't really the responsibility of

929
00:35:34.350 --> 00:35:36.110
the people whose satellite was smashed. You'd

930
00:35:36.110 --> 00:35:38.390
have thought to account for all of the debris

931
00:35:38.390 --> 00:35:40.110
that was generated by their satellite being

932
00:35:40.110 --> 00:35:42.670
hit by something that wasn't theirs. I mean,

933
00:35:42.670 --> 00:35:44.270
that would be an interesting claim to put in

934
00:35:44.270 --> 00:35:45.790
for the insurance. Normally if you're in a

935
00:35:45.790 --> 00:35:48.470
bit of a car bump, you claim from the other

936
00:35:48.470 --> 00:35:51.230
driver's insurance. That's how it works. But

937
00:35:51.390 --> 00:35:53.510
a lot of the debris up there isn't like it's

938
00:35:53.510 --> 00:35:55.430
cataloged, that this is a property of the US

939
00:35:55.430 --> 00:35:57.670
this is the property of spare techs. It's a

940
00:35:57.670 --> 00:35:59.150
bit of debris. There's large amounts of

941
00:35:59.150 --> 00:36:00.750
debris up there that is too small for us to

942
00:36:00.750 --> 00:36:01.550
effectively track.

943
00:36:02.370 --> 00:36:04.810
Andrew Dunkley: Yeah, well, things as small as paint flicks,

944
00:36:04.810 --> 00:36:07.090
but they're moving at thousands of kilometers

945
00:36:07.090 --> 00:36:07.530
an hour.

946
00:36:07.530 --> 00:36:10.290
Jonti Horner: Yeah, it's challenging. And I think we

947
00:36:10.850 --> 00:36:13.450
take space and our use of space for granted

948
00:36:13.450 --> 00:36:15.610
nowadays. It's not like the 1960s where

949
00:36:15.610 --> 00:36:18.330
people accepted that human space flight was

950
00:36:18.330 --> 00:36:21.210
dangerous. People will die. We just get

951
00:36:21.210 --> 00:36:23.330
on with it. There's been a big transition. I

952
00:36:23.330 --> 00:36:25.730
think that was a big part of why we

953
00:36:26.290 --> 00:36:28.130
stopped going back to the moon, or rather why

954
00:36:28.130 --> 00:36:30.170
it's taken so long to go back, should I say?

955
00:36:30.170 --> 00:36:31.770
And similarly, it's why the shuttle program

956
00:36:31.770 --> 00:36:34.390
eventually came to an end. That shift in

957
00:36:34.390 --> 00:36:36.070
public consciousness from when the Challenger

958
00:36:36.070 --> 00:36:38.430
disaster happened, when people were like,

959
00:36:38.430 --> 00:36:40.470
this is very sad, but we need the space

960
00:36:40.470 --> 00:36:42.910
shuttle to when the second disaster happened,

961
00:36:43.550 --> 00:36:46.190
and that was too much. We've had this

962
00:36:46.350 --> 00:36:48.070
shift in the public conscious and it's Kind

963
00:36:48.070 --> 00:36:50.070
of grounded in that idea that space is easy

964
00:36:50.070 --> 00:36:51.670
and it really isn't. This is just a reminder

965
00:36:51.670 --> 00:36:54.030
that space is hard. There are going to be

966
00:36:54.030 --> 00:36:56.310
problems in the future. And it's an

967
00:36:56.310 --> 00:36:58.150
interesting challenge to balance off the

968
00:36:58.150 --> 00:37:01.110
needs of commercial enterprise and the needs

969
00:37:01.110 --> 00:37:03.230
of human spaceflight and the regulation

970
00:37:03.310 --> 00:37:05.910
involved, when pretty much everybody involved

971
00:37:05.910 --> 00:37:08.510
benefits from it not being that regulated. So

972
00:37:08.510 --> 00:37:09.990
there's not much of an incentive. It's a bit

973
00:37:09.990 --> 00:37:11.790
like asking fossil fuel companies to

974
00:37:11.790 --> 00:37:13.750
legislate about climate change or cigarette

975
00:37:13.750 --> 00:37:15.550
companies to legislate about cancer.

976
00:37:15.870 --> 00:37:16.270
Andrew Dunkley: Yeah.

977
00:37:16.270 --> 00:37:17.950
Jonti Horner: It's not in their interest to do so.

978
00:37:18.910 --> 00:37:21.690
Andrew Dunkley: No. No. But we do wish the Chinese, uh,

979
00:37:22.030 --> 00:37:24.670
astronauts well. And I'm sure they'll be

980
00:37:24.670 --> 00:37:27.510
home pretty soon. We hope so. Anyway.

981
00:37:27.510 --> 00:37:30.100
Um, I just thought I'd better check because,

982
00:37:30.130 --> 00:37:33.060
uh, we don't call Russian astronauts

983
00:37:33.060 --> 00:37:34.900
astronauts. They're cosmonauts. Chinese

984
00:37:35.060 --> 00:37:36.980
astronauts are officially astronauts, but

985
00:37:36.980 --> 00:37:38.660
they're also known as tychonauts.

986
00:37:39.380 --> 00:37:42.220
Jonti Horner: Yeah, it's a really interesting one. And I'm

987
00:37:42.220 --> 00:37:44.859
not an. Is it etymologist or entomologist.

988
00:37:44.859 --> 00:37:46.420
One of them is about words and one of them's

989
00:37:46.420 --> 00:37:48.460
around beetles. But I'm not into the science

990
00:37:48.460 --> 00:37:51.340
of the study of words. But there

991
00:37:51.340 --> 00:37:54.100
has been this idea of every nation

992
00:37:54.180 --> 00:37:56.900
having its own unique name for those that

993
00:37:56.900 --> 00:37:59.420
they sent to space. Um, where you have

994
00:37:59.420 --> 00:38:01.820
cosmonauts and tychonauts. It does make me

995
00:38:01.820 --> 00:38:03.620
wonder if Australian ones will be skipping

996
00:38:03.620 --> 00:38:06.140
out. So, hoppy notes or, um, I'm thinking

997
00:38:06.140 --> 00:38:08.460
diggernauts. Yeah. Drop by notes.

998
00:38:09.740 --> 00:38:11.860
There was a story which is sufficiently out

999
00:38:11.860 --> 00:38:13.460
of my field that we're not talking about it,

1000
00:38:13.460 --> 00:38:15.100
but there was a story that cropped up on the

1001
00:38:15.100 --> 00:38:17.580
BBC last week that somebody has discovered

1002
00:38:17.580 --> 00:38:20.140
droc crop fossils. Drock

1003
00:38:20.380 --> 00:38:23.180
Drop croc fossils. So anybody

1004
00:38:23.180 --> 00:38:25.420
who's been to Australia or knows Australians

1005
00:38:25.810 --> 00:38:28.010
knows about drop bears, which are a terrible

1006
00:38:28.010 --> 00:38:30.090
pest. And we have to deal with them. Um, we

1007
00:38:30.090 --> 00:38:31.770
do. They're a nightmare. You should look at

1008
00:38:31.770 --> 00:38:33.250
the Australian museums. Drop bears.

1009
00:38:33.250 --> 00:38:35.170
Andrew Dunkley: I mean, people worry about spiders and snakes

1010
00:38:35.170 --> 00:38:37.330
and. And jellyfish. No, that's the drop

1011
00:38:37.330 --> 00:38:37.730
bears.

1012
00:38:37.890 --> 00:38:40.210
Jonti Horner: Something to share on the Facebook group

1013
00:38:40.210 --> 00:38:42.170
would be the Australia Museum's drop bear

1014
00:38:42.170 --> 00:38:45.130
page, because they've got a location map

1015
00:38:45.130 --> 00:38:46.810
for them and a large description. So for

1016
00:38:46.810 --> 00:38:49.050
those interested in drop bears can really

1017
00:38:49.050 --> 00:38:50.570
strongly recommend that. But there was an

1018
00:38:50.570 --> 00:38:53.490
article came out in the BBC, um, and I think

1019
00:38:53.490 --> 00:38:55.650
a few other reputable science journalism

1020
00:38:55.650 --> 00:38:58.370
outlets last week talking about fossilized

1021
00:38:58.450 --> 00:39:01.250
drop crocs. So the idea that there was a

1022
00:39:01.250 --> 00:39:03.490
species of crocodile in Australia a few tens

1023
00:39:03.490 --> 00:39:06.010
of millions of years ago that used to climb

1024
00:39:06.010 --> 00:39:08.170
up Trees and drop hunt in the same way

1025
00:39:08.170 --> 00:39:10.170
leopards do. So you'd have crocodiles jumping

1026
00:39:10.170 --> 00:39:12.650
out of trees onto their prey. Oh, my word.

1027
00:39:12.650 --> 00:39:15.410
So, yeah, yeah, Dropper nauts would probably

1028
00:39:15.410 --> 00:39:17.810
be an appropriate Australian.

1029
00:39:17.810 --> 00:39:19.990
Andrew Dunkley: Yeah, I'm, um, actually, I'm actually

1030
00:39:19.990 --> 00:39:20.310
looking.

1031
00:39:20.310 --> 00:39:23.190
Jonti Horner: At the Drop Bear map. It's upload, isn't it?

1032
00:39:25.190 --> 00:39:28.070
Andrew Dunkley: I love the, the, the, the, the. The shape of

1033
00:39:28.070 --> 00:39:29.590
the location in Central Australia.

1034
00:39:29.670 --> 00:39:31.830
Jonti Horner: That's. Yeah, that's a river.

1035
00:39:31.990 --> 00:39:34.389
Absolutely. So always remember to wear your

1036
00:39:34.389 --> 00:39:35.430
hat with the corks on.

1037
00:39:35.910 --> 00:39:37.870
Andrew Dunkley: Oh, yeah, that keeps them away. They don't

1038
00:39:37.870 --> 00:39:40.550
like corks. Okay, moving, uh,

1039
00:39:40.830 --> 00:39:42.910
on. This is Space Nuts with Andrew Dunkley

1040
00:39:42.910 --> 00:39:44.630
and Professor Jonti Horner.

1041
00:39:49.200 --> 00:39:52.080
Space Nuts to our

1042
00:39:52.080 --> 00:39:54.440
final story. And, uh, this is, this is a bit

1043
00:39:54.440 --> 00:39:56.880
of a fun one. Uh, the Pleiades.

1044
00:39:57.790 --> 00:39:59.080
Jonti Horner: Um, what.

1045
00:39:59.080 --> 00:40:00.240
Andrew Dunkley: What's going on with them?

1046
00:40:01.040 --> 00:40:02.400
Jonti Horner: Well, the Pleiades are.

1047
00:40:02.400 --> 00:40:05.240
Andrew Dunkley: Oh, oh, yeah, sorry, sorry. No,

1048
00:40:05.240 --> 00:40:07.960
I just. The Pleiades are the subject, but

1049
00:40:07.960 --> 00:40:10.360
the, but the topic is actually chasing stars

1050
00:40:10.360 --> 00:40:11.920
using gyochronology.

1051
00:40:13.320 --> 00:40:14.080
Jonti Horner: Gyrochronology.

1052
00:40:14.080 --> 00:40:15.400
Andrew Dunkley: Gyrochronology, yes.

1053
00:40:15.400 --> 00:40:17.120
Jonti Horner: A couple of other things. It's the beauty of

1054
00:40:17.120 --> 00:40:19.000
being able to bring together

1055
00:40:20.120 --> 00:40:21.800
different fields of astronomy with different

1056
00:40:21.800 --> 00:40:24.480
data. It actually ties into a fabulous

1057
00:40:24.480 --> 00:40:26.840
Australian project that I was part of for a

1058
00:40:26.840 --> 00:40:29.000
good long time, uh, that I need to get back

1059
00:40:29.000 --> 00:40:30.520
involved with at some time, to be honest,

1060
00:40:30.600 --> 00:40:32.240
that I think Fred's been involved with a bit

1061
00:40:32.240 --> 00:40:34.680
as well, called Galah, which is Galahia

1062
00:40:34.680 --> 00:40:37.440
archeology with Hermes. And this is, uh, a

1063
00:40:37.440 --> 00:40:39.560
means by which we can look for stars that

1064
00:40:39.560 --> 00:40:42.500
form together and do archeology that digs

1065
00:40:42.500 --> 00:40:44.180
into the history of star formation in the

1066
00:40:44.180 --> 00:40:46.740
Milky Way by looking at the spectra of stars,

1067
00:40:46.740 --> 00:40:48.940
figuring out their compositions, looking at

1068
00:40:48.940 --> 00:40:51.100
the abundances of elements within those stars

1069
00:40:51.100 --> 00:40:53.580
to find their stellar twins, the stars that

1070
00:40:53.580 --> 00:40:56.100
they formed with long ago that have that same

1071
00:40:56.100 --> 00:40:58.820
chemical fingerprint of their original

1072
00:40:58.820 --> 00:41:01.380
formation. This story links to that, but it's

1073
00:41:01.380 --> 00:41:03.660
not actually using Galar data. It's using a

1074
00:41:03.660 --> 00:41:06.660
variety of other data. The story is that we

1075
00:41:06.660 --> 00:41:09.110
have the most famous

1076
00:41:09.350 --> 00:41:11.430
star cluster in the night sky, the Pleiades,

1077
00:41:11.430 --> 00:41:14.270
the seven sisters to people in Japan. This

1078
00:41:14.270 --> 00:41:16.230
was Subaru. But basically every

1079
00:41:17.190 --> 00:41:19.870
culture across the planet can see the

1080
00:41:19.870 --> 00:41:22.390
Pleiades, ah, within about 25 degrees

1081
00:41:22.790 --> 00:41:25.270
of the celestial equator. They're not very

1082
00:41:25.270 --> 00:41:26.990
far from the ecliptic. In fact, you often see

1083
00:41:26.990 --> 00:41:29.750
beautiful photos of the Moon or the planets

1084
00:41:29.750 --> 00:41:32.030
near the Pleiades. So they're visible from

1085
00:41:32.030 --> 00:41:34.230
basically the entire inhabited surface of the

1086
00:41:34.230 --> 00:41:36.360
Earth. Uh, they're very beloved of people.

1087
00:41:36.360 --> 00:41:38.440
There's a lot of wonderful cultural stories

1088
00:41:38.440 --> 00:41:40.880
that talk about them. There was a fabulous

1089
00:41:40.960 --> 00:41:43.680
study looking at the traditional knowledge of

1090
00:41:43.680 --> 00:41:45.720
the traditional owners here in Australia from

1091
00:41:45.720 --> 00:41:48.120
some of the groups who talked about the

1092
00:41:48.120 --> 00:41:50.640
Pleiades being protected by the bright star

1093
00:41:50.640 --> 00:41:53.560
in Taurus, Aldebaran, who was a wise woman,

1094
00:41:53.560 --> 00:41:56.320
protecting these young women from a fairly.

1095
00:41:56.400 --> 00:41:58.560
A man with fairly voracious appetites in the

1096
00:41:58.560 --> 00:42:01.290
form of Beetlejuice in Orion and Betelgeuse,

1097
00:42:01.290 --> 00:42:04.090
and Aldebaran fighting using fire magic, and,

1098
00:42:04.090 --> 00:42:06.850
um, the magic building up and flaring off and

1099
00:42:07.010 --> 00:42:09.730
them having this fight, which is a fabulous

1100
00:42:09.810 --> 00:42:11.770
story, but it also ties into the fact that

1101
00:42:11.770 --> 00:42:14.250
both Betelgeuse and Eldebaran are variable

1102
00:42:14.250 --> 00:42:16.690
stars. And, um, this story is

1103
00:42:16.930 --> 00:42:19.450
taking their variability into account in part

1104
00:42:19.450 --> 00:42:22.330
of the folklore and the storytelling of what

1105
00:42:22.330 --> 00:42:23.970
is culturally right and wrong, what is the

1106
00:42:23.970 --> 00:42:26.130
right way to behave, and in doing so,

1107
00:42:26.130 --> 00:42:28.370
encoding astronomical data. So that's a study

1108
00:42:28.370 --> 00:42:30.730
that, uh, my colleague Duane Hamacher, down

1109
00:42:30.730 --> 00:42:32.210
at the University of Melbourne was telling me

1110
00:42:32.210 --> 00:42:34.370
about, that he was involved with, which is

1111
00:42:34.370 --> 00:42:37.050
fabulous work. So the Pleiades

1112
00:42:37.050 --> 00:42:39.050
are really, uh, important to cultures all

1113
00:42:39.050 --> 00:42:40.570
across the globe. They're very beloved.

1114
00:42:40.570 --> 00:42:42.530
They're very easy to see with the naked eye.

1115
00:42:42.850 --> 00:42:44.650
Depending on how good your eyesight is and

1116
00:42:44.650 --> 00:42:46.650
how good your location is, most people will

1117
00:42:46.650 --> 00:42:48.970
see six, seven or eight of them. You know, I

1118
00:42:48.970 --> 00:42:50.450
can normally pick up eight or nine on a

1119
00:42:50.450 --> 00:42:52.530
really good dark site, six or seven when it's

1120
00:42:52.530 --> 00:42:54.450
less so. Uh, and that's why, for a lot of

1121
00:42:54.450 --> 00:42:56.210
people, they're considered the Seven Sisters.

1122
00:42:56.790 --> 00:42:59.070
There is a guy in Italy who used to claim he

1123
00:42:59.070 --> 00:43:01.230
could see 82 of these stars with the unaided

1124
00:43:01.230 --> 00:43:03.030
eye. And I think it's fair to say that nobody

1125
00:43:03.030 --> 00:43:05.230
believed him. If you look at the cluster with

1126
00:43:05.230 --> 00:43:07.150
binoculars or a telescope, you see far more.

1127
00:43:07.150 --> 00:43:09.630
So the stars we see with the naked eye are

1128
00:43:09.630 --> 00:43:11.390
the ones that are the superstars. They're the

1129
00:43:11.390 --> 00:43:13.110
most massive, the most luminous, these

1130
00:43:13.110 --> 00:43:14.950
bright, beautiful blue stars.

1131
00:43:16.070 --> 00:43:17.950
Now, what we know about star clusters like

1132
00:43:17.950 --> 00:43:20.350
the Pleiades, like the Hyades, like Prispe,

1133
00:43:20.350 --> 00:43:23.150
the Beehive, is that these agglomerations of

1134
00:43:23.150 --> 00:43:24.950
stars are stars that formed in the same

1135
00:43:24.950 --> 00:43:26.710
stellar nursery. They were all born together,

1136
00:43:27.630 --> 00:43:29.710
but the cluster does not have enough mass

1137
00:43:29.790 --> 00:43:32.510
that it will stay discrete and held together

1138
00:43:32.990 --> 00:43:35.800
forevermore under gravity. Um,

1139
00:43:35.800 --> 00:43:38.470
unlike globular clusters, which are as old as

1140
00:43:38.470 --> 00:43:40.070
the Galaxy and are very different, they're

1141
00:43:40.070 --> 00:43:42.070
kind of a million stars packed into a small

1142
00:43:42.070 --> 00:43:44.470
space. Open clusters are typically a few

1143
00:43:44.470 --> 00:43:46.950
hundred or a few thousand stars. And so what

1144
00:43:46.950 --> 00:43:49.190
tends to happen a bit like young kids is, you

1145
00:43:49.190 --> 00:43:50.470
know, they hang around Together while they're

1146
00:43:50.470 --> 00:43:51.990
at school, while they're at nursery. But then

1147
00:43:51.990 --> 00:43:53.430
as they move into their adult lives, they

1148
00:43:53.430 --> 00:43:55.960
disperse off and go their separate ways. Um,

1149
00:43:55.960 --> 00:43:57.450
and what that means for clusters like the

1150
00:43:57.450 --> 00:44:00.370
Pleiades is gradually the stars towards

1151
00:44:00.370 --> 00:44:02.410
the outer edges of the cluster, uh, will

1152
00:44:02.410 --> 00:44:04.730
gradually get nudged and tugged. So they fall

1153
00:44:04.730 --> 00:44:06.530
away from the cluster, start to move freely

1154
00:44:06.530 --> 00:44:08.410
through the galaxy, separate to the cluster,

1155
00:44:08.570 --> 00:44:11.289
and the cluster disperses and it kind of gets

1156
00:44:11.289 --> 00:44:13.730
whittled away from the outside in. And what

1157
00:44:13.730 --> 00:44:16.650
we see with the Pleiades on the sky is a core

1158
00:44:16.650 --> 00:44:18.690
kernel, the very central area, which has the

1159
00:44:18.690 --> 00:44:21.370
most massive stars in all hanging around. And

1160
00:44:21.370 --> 00:44:22.970
the idea is that when the Pleiades were

1161
00:44:22.970 --> 00:44:25.410
younger, there were more members still bound

1162
00:44:25.410 --> 00:44:26.890
to the cluster. The cluster was bigger. And

1163
00:44:26.890 --> 00:44:28.530
the cluster's been shedding members over

1164
00:44:28.530 --> 00:44:31.130
time, and that's fairly well established. But

1165
00:44:31.130 --> 00:44:33.410
it's really interesting to think about where

1166
00:44:33.410 --> 00:44:35.530
those members have gone. You know, it's like

1167
00:44:35.530 --> 00:44:37.330
looking back at a band from youth. What did

1168
00:44:37.330 --> 00:44:39.490
they do now? Where are they now? Those old TV

1169
00:44:39.490 --> 00:44:41.690
shows, Where are the former members of the

1170
00:44:41.690 --> 00:44:44.650
Pleiades? Now, this has led to the concept

1171
00:44:44.650 --> 00:44:47.130
of the greater Pleiades complex. So if you

1172
00:44:47.130 --> 00:44:50.020
could, with good enough precision, get lots

1173
00:44:50.020 --> 00:44:52.940
of data about all the stars in the sky, you

1174
00:44:52.940 --> 00:44:54.780
could, in theory, identify those ones that

1175
00:44:54.780 --> 00:44:57.060
formed in the Pleiades but have disappeared.

1176
00:44:57.220 --> 00:44:59.020
And, um, that's what this work has tried to

1177
00:44:59.020 --> 00:45:01.420
do. There have been previous estimates that

1178
00:45:01.420 --> 00:45:03.300
have just looked at, uh, the positions on the

1179
00:45:03.300 --> 00:45:05.860
sky and the motion of the stars to see if

1180
00:45:05.860 --> 00:45:07.780
that motion is compatible with them having

1181
00:45:07.780 --> 00:45:09.340
formed in the Pleiades. Are they moving

1182
00:45:09.340 --> 00:45:11.140
through space at about the same speed as the

1183
00:45:11.140 --> 00:45:13.980
Pleiades, but moving away from the Pleiades

1184
00:45:13.980 --> 00:45:16.060
at such a speed that they would have been

1185
00:45:16.060 --> 00:45:18.740
near the Pleiades when they formed? Now, that

1186
00:45:18.740 --> 00:45:20.660
was problematic because it will capture a lot

1187
00:45:20.660 --> 00:45:22.300
of stars that just happen to be in the

1188
00:45:22.300 --> 00:45:24.100
vicinity of the Pleiades when they formed,

1189
00:45:24.100 --> 00:45:26.260
but were already there. You know, they were

1190
00:45:26.260 --> 00:45:27.860
near the star forming region, but they were

1191
00:45:27.860 --> 00:45:29.940
not involved. I guess it's a bit like, you

1192
00:45:29.940 --> 00:45:31.459
know, trying to figure out all the babies

1193
00:45:31.459 --> 00:45:33.340
that were born in a hospital on a certain day

1194
00:45:33.660 --> 00:45:35.700
by saying anything that was in a, within a

1195
00:45:35.700 --> 00:45:37.380
kilometer of the hospital could potentially

1196
00:45:37.380 --> 00:45:39.140
have been a baby that was born there. But

1197
00:45:39.140 --> 00:45:40.940
you've got a lot of people commuting past on

1198
00:45:40.940 --> 00:45:43.790
the highway at the time. Just so happens

1199
00:45:44.190 --> 00:45:46.590
what this new study has done is it's taken

1200
00:45:47.070 --> 00:45:49.350
data on the stars from NASA's Exoplanet

1201
00:45:49.350 --> 00:45:51.070
Survey Satellite tests. The transiting

1202
00:45:51.070 --> 00:45:53.390
exoplanet Survey satellite that's been

1203
00:45:53.390 --> 00:45:56.150
scouring basically the entire sky gives you a

1204
00:45:56.150 --> 00:45:58.910
wealth of data on how stars behave. You've

1205
00:45:58.910 --> 00:46:01.590
got the Gaia spacecraft, which is a

1206
00:46:01.590 --> 00:46:03.430
European Space Agency mission that has

1207
00:46:03.430 --> 00:46:05.270
stopped observing now, but is still providing

1208
00:46:05.270 --> 00:46:06.990
lots of data updates. And we're looking

1209
00:46:06.990 --> 00:46:09.870
forward to BR4 from that next year from the

1210
00:46:09.870 --> 00:46:12.510
exoplanet side of things. But Gaia has given

1211
00:46:12.510 --> 00:46:15.230
us incredibly precise positions on the sky,

1212
00:46:15.870 --> 00:46:18.590
incredibly precise distances, and

1213
00:46:18.590 --> 00:46:21.430
incredibly precise movement information about

1214
00:46:21.430 --> 00:46:23.910
the stars. So we know very accurately where

1215
00:46:23.910 --> 00:46:26.470
they are in space and how they're moving. And

1216
00:46:26.470 --> 00:46:28.150
the team behind this work have brought into

1217
00:46:28.150 --> 00:46:31.150
it the third bit of information, which is

1218
00:46:31.390 --> 00:46:34.190
gyrochronology. So this is an attempt

1219
00:46:34.980 --> 00:46:36.820
to figure out the edges of stars. And once

1220
00:46:36.820 --> 00:46:38.580
stars are on the main sequence, once they're

1221
00:46:38.580 --> 00:46:41.220
in the prime of life, it's very challenging

1222
00:46:41.220 --> 00:46:43.180
to figure out how old they are because they

1223
00:46:43.180 --> 00:46:45.220
sit there basically doing very little,

1224
00:46:45.220 --> 00:46:47.980
changing very little. Perry the Platypus,

1225
00:46:47.980 --> 00:46:49.780
he's a platypus. They don't do much. It's

1226
00:46:49.780 --> 00:46:52.180
that same kind of idea, just sits on the main

1227
00:46:52.180 --> 00:46:54.180
sequence, trundling along, barely changing.

1228
00:46:54.980 --> 00:46:57.180
Now, there are means like

1229
00:46:57.180 --> 00:46:59.540
asteroseismology, measuring the wibbling and

1230
00:46:59.540 --> 00:47:01.540
the wobbling and the starquakes on a star

1231
00:47:01.970 --> 00:47:03.650
that can tell you a lot about its interior

1232
00:47:03.650 --> 00:47:05.570
and allow you to infer an edge. And that's

1233
00:47:05.570 --> 00:47:08.250
what some of my colleagues at UNISQ do. But

1234
00:47:08.250 --> 00:47:10.170
that's very time consuming and challenging.

1235
00:47:10.170 --> 00:47:12.570
So you kind of have to do one star at a time

1236
00:47:12.570 --> 00:47:14.450
and dedicate a lot of observations to do

1237
00:47:14.450 --> 00:47:15.770
this, because you've got to measure all the

1238
00:47:15.770 --> 00:47:17.250
different frequencies at which that star

1239
00:47:17.250 --> 00:47:19.690
vibrates and wobbles. So that's good for

1240
00:47:19.690 --> 00:47:22.170
individual stars, but it's not good for a

1241
00:47:22.170 --> 00:47:25.010
population survey like this. So going

1242
00:47:25.010 --> 00:47:27.810
back about 20 years, a couple of researchers

1243
00:47:27.810 --> 00:47:30.400
noticed that for stars where we had

1244
00:47:30.400 --> 00:47:32.600
relatively good understanding of their ages,

1245
00:47:33.160 --> 00:47:35.200
that were less massive than a spectral class

1246
00:47:35.200 --> 00:47:37.520
of F8. So these are sun like stars, or a

1247
00:47:37.520 --> 00:47:39.600
little bit more massive, going all the way

1248
00:47:39.600 --> 00:47:42.280
down to red dwarfs. They found that there is

1249
00:47:42.280 --> 00:47:44.799
a broad relationship that the older the star

1250
00:47:44.799 --> 00:47:47.640
is, the slower it spins. And this

1251
00:47:47.640 --> 00:47:49.640
makes sense. You know, our sun is shedding

1252
00:47:49.640 --> 00:47:51.880
angular momentum with the solar wind

1253
00:47:52.360 --> 00:47:54.600
as material is flung off. So it's gradually

1254
00:47:54.600 --> 00:47:57.060
spinning down and it's a very, very, very

1255
00:47:57.060 --> 00:47:59.820
slow process. But given that stars live very

1256
00:47:59.820 --> 00:48:01.340
long lives, it's something that is

1257
00:48:01.340 --> 00:48:04.300
quantifiable and measurable. So the idea

1258
00:48:04.300 --> 00:48:06.100
here is that if you find stars that are

1259
00:48:06.100 --> 00:48:08.780
spinning quickly, then they are probably

1260
00:48:08.780 --> 00:48:11.300
young. And so the team involved with this

1261
00:48:11.300 --> 00:48:13.980
study, took this master list of all the

1262
00:48:13.980 --> 00:48:16.860
stars that have positions and velocities

1263
00:48:17.340 --> 00:48:19.740
compatible with them being near the Pleiades.

1264
00:48:19.740 --> 00:48:22.420
When the Pleiades formed and did an edge

1265
00:48:22.420 --> 00:48:24.180
check on them, they ID'd them effectively.

1266
00:48:24.580 --> 00:48:27.060
They said, how old are you? Measured the spin

1267
00:48:27.060 --> 00:48:28.700
rates, which is the kind of information you

1268
00:48:28.700 --> 00:48:31.350
can get from missions like tess. And, um,

1269
00:48:31.350 --> 00:48:33.940
they set a limit that I think the SARS had to

1270
00:48:33.940 --> 00:48:36.140
be spinning with rotation rates of 12 days or

1271
00:48:36.140 --> 00:48:38.340
shorter to be young enough.

1272
00:48:38.900 --> 00:48:40.860
That allowed them to filter the list down

1273
00:48:40.860 --> 00:48:43.460
significantly and left them just over

1274
00:48:43.460 --> 00:48:45.860
3,000 candidate stars that are

1275
00:48:46.180 --> 00:48:48.500
probably members of this greater Pleiades

1276
00:48:48.500 --> 00:48:50.660
complex. And those stars are spread on all

1277
00:48:50.660 --> 00:48:53.300
over the night sky. They're concentrated

1278
00:48:53.300 --> 00:48:54.700
through the Milky Way, through the plane of

1279
00:48:54.700 --> 00:48:56.980
the galaxy. And that's perfectly making

1280
00:48:56.980 --> 00:48:58.980
sense, because star clusters tend to form

1281
00:48:58.980 --> 00:49:01.500
very close to the plane of the galaxy. They

1282
00:49:01.500 --> 00:49:03.700
tend to be dynamically kind of cold. They

1283
00:49:03.700 --> 00:49:06.060
tend to be on very flat orbits. So these

1284
00:49:06.060 --> 00:49:08.060
things have spread out along the plane of the

1285
00:49:08.060 --> 00:49:09.700
galaxy in both directions, away from the

1286
00:49:09.700 --> 00:49:11.980
Pleiades in the sky. But because some of

1287
00:49:11.980 --> 00:49:14.820
these stars are relatively nearby to us, some

1288
00:49:14.820 --> 00:49:16.900
are passing above or, uh, below us. So

1289
00:49:16.900 --> 00:49:18.940
basically, any direction in the sky that you

1290
00:49:18.940 --> 00:49:21.540
look, you might see a star that was born with

1291
00:49:21.540 --> 00:49:24.340
the Pleiades, um, tens of millions of years

1292
00:49:24.340 --> 00:49:26.460
ago. It used to be that the Pleiades were

1293
00:49:26.460 --> 00:49:28.460
said to be about 65 million years old. I

1294
00:49:28.460 --> 00:49:30.060
think the accepted wisdom now is that they're

1295
00:49:30.060 --> 00:49:32.379
about 100 million years old. And, uh, that

1296
00:49:32.379 --> 00:49:34.060
gives you a lot of time to move a very long

1297
00:49:34.060 --> 00:49:36.060
way away from the cluster if you've escaped.

1298
00:49:36.380 --> 00:49:38.380
Yeah. So these stars are just spread all

1299
00:49:38.380 --> 00:49:40.780
across the sky, and it's a really lovely

1300
00:49:41.020 --> 00:49:43.660
insight into the lives of these clusters

1301
00:49:44.220 --> 00:49:46.780
and to the way that we can do kind of

1302
00:49:46.940 --> 00:49:49.340
stellar and galactic archeology effectively.

1303
00:49:49.340 --> 00:49:51.180
We can get insights into the formation

1304
00:49:51.180 --> 00:49:53.980
history of our galaxy and how clusters form

1305
00:49:53.980 --> 00:49:56.820
and evolve. It's really beautiful. And it is.

1306
00:49:56.820 --> 00:49:59.060
You know, my partner's big into archeology.

1307
00:49:59.060 --> 00:50:00.860
She loves watching Time Team with Tony

1308
00:50:00.860 --> 00:50:02.820
Robinson. And this is effectively like a Time

1309
00:50:02.820 --> 00:50:05.740
Team episode in the sky. Hm.

1310
00:50:05.740 --> 00:50:07.620
Andrew Dunkley: It is fascinating. We don't think about it

1311
00:50:07.620 --> 00:50:09.540
much. We look up. Most people probably just

1312
00:50:09.540 --> 00:50:10.940
look up at the stars and go, ah, they're

1313
00:50:10.940 --> 00:50:13.930
pretty. But they don't think about how

1314
00:50:13.930 --> 00:50:16.810
over time they've moved around. And it goes

1315
00:50:16.810 --> 00:50:19.690
back to a story Fred and I talked about more

1316
00:50:19.690 --> 00:50:21.890
than once, and that is that, uh, our

1317
00:50:22.690 --> 00:50:25.290
son was probably a member of a

1318
00:50:25.290 --> 00:50:28.210
binary, um, and had a sister star

1319
00:50:29.090 --> 00:50:32.090
or a twin that we are still looking for.

1320
00:50:32.090 --> 00:50:34.010
It's out there somewhere, probably, but we

1321
00:50:34.010 --> 00:50:36.690
haven't found it yet. But, um, yeah,

1322
00:50:37.060 --> 00:50:39.960
uh, it's a fascinating study and I, uh, like

1323
00:50:39.960 --> 00:50:41.560
the sound of it. You can read all about

1324
00:50:41.560 --> 00:50:43.840
it@space.com or you can go to

1325
00:50:43.840 --> 00:50:46.800
abc.net au on their science

1326
00:50:46.800 --> 00:50:49.760
pages and check that out. Uh,

1327
00:50:50.120 --> 00:50:52.200
we are done. Jonti, thank you so much.

1328
00:50:52.280 --> 00:50:54.400
Jonti Horner: That's all good. And sorry for the unexpected

1329
00:50:54.400 --> 00:50:55.680
interruption in the middle there, but

1330
00:50:55.680 --> 00:50:57.440
insurance companies got to do what insurance

1331
00:50:57.440 --> 00:50:58.760
companies got to do, unfortunately.

1332
00:50:59.400 --> 00:51:01.720
Andrew Dunkley: They have got to do that, whatever they do.

1333
00:51:02.840 --> 00:51:04.560
I thought of another name for an Australian

1334
00:51:04.560 --> 00:51:05.160
astronaut.

1335
00:51:05.350 --> 00:51:05.590
Jonti Horner: Yes.

1336
00:51:05.590 --> 00:51:06.190
Andrew Dunkley: You ready?

1337
00:51:06.190 --> 00:51:06.430
Jonti Horner: Yeah.

1338
00:51:06.430 --> 00:51:09.030
Andrew Dunkley: A Yobo Nord. I

1339
00:51:09.030 --> 00:51:11.910
reckon that would. That'd probably be a

1340
00:51:11.910 --> 00:51:12.110
winner.

1341
00:51:12.110 --> 00:51:14.790
Jonti Horner: Well, you recruit that. Recruit them from.

1342
00:51:14.790 --> 00:51:16.870
You could have Larry Connaughts. Larry

1343
00:51:16.870 --> 00:51:18.950
Connect. Uh, or Boganuts.

1344
00:51:19.670 --> 00:51:20.470
Andrew Dunkley: Boganauts.

1345
00:51:20.470 --> 00:51:20.830
Jonti Horner: Yes.

1346
00:51:20.830 --> 00:51:23.070
Andrew Dunkley: Well, we have a shire west of us called Bogan

1347
00:51:23.070 --> 00:51:23.830
Shire, so.

1348
00:51:23.990 --> 00:51:26.470
Jonti Horner: And of course, if you. If you send any pets

1349
00:51:26.470 --> 00:51:28.150
to space, you could probably have blueynauts

1350
00:51:28.150 --> 00:51:28.550
as well.

1351
00:51:28.550 --> 00:51:29.310
Andrew Dunkley: Bluey notes.

1352
00:51:29.310 --> 00:51:29.750
Jonti Horner: Yes.

1353
00:51:29.830 --> 00:51:32.190
Andrew Dunkley: That'd be popular. And you can't wear boots

1354
00:51:32.190 --> 00:51:33.590
to space. You got to wear thongs.

1355
00:51:33.590 --> 00:51:33.940
Jonti Horner: Yes.

1356
00:51:34.650 --> 00:51:36.850
Andrew Dunkley: Which everyone else calls flip flops or

1357
00:51:36.850 --> 00:51:38.690
jandals or something, but we've somehow

1358
00:51:38.690 --> 00:51:40.730
managed to turn a pair of underpants into

1359
00:51:40.730 --> 00:51:41.330
footwear.

1360
00:51:41.330 --> 00:51:43.490
Jonti Horner: Yeah. Anyway, what's a constant source of

1361
00:51:43.490 --> 00:51:45.410
confusion for shop owners in the uk? When

1362
00:51:45.410 --> 00:51:47.450
Aussies came in and went into a shoe shop

1363
00:51:47.450 --> 00:51:49.730
asking where they keep their thongs. And, um,

1364
00:51:49.730 --> 00:51:51.610
it was always quite entertaining seeing

1365
00:51:51.610 --> 00:51:54.170
people's faces as the staff kind of react.

1366
00:51:55.290 --> 00:51:58.250
Andrew Dunkley: That's a whole different story. Um, anyway,

1367
00:51:58.250 --> 00:51:59.290
Jotty, thank you, uh, so much.

1368
00:51:59.290 --> 00:52:00.650
Jonti Horner: It's been a pleasure. It's an absolute

1369
00:52:00.650 --> 00:52:02.720
pleasure. Thank you for having me. Always.

1370
00:52:02.800 --> 00:52:03.200
Good.

1371
00:52:03.290 --> 00:52:05.880
Andrew Dunkley: Uh, John T. Horner, professor of Astrophysics

1372
00:52:05.880 --> 00:52:07.880
at the University of Southern Queensland. And

1373
00:52:07.880 --> 00:52:09.520
thanks to Huw in the studio, who

1374
00:52:10.560 --> 00:52:12.360
didn't much help today because, you know,

1375
00:52:12.360 --> 00:52:14.680
he's got a second job. Uh, he's an Uber

1376
00:52:14.680 --> 00:52:17.440
driver, and he got a text to pick

1377
00:52:17.440 --> 00:52:20.200
up some Chinese astronauts from the

1378
00:52:20.200 --> 00:52:23.120
Tiangong Space Station, so he's on his way.

1379
00:52:23.790 --> 00:52:26.230
Uh, don't forget to visit us online at, uh,

1380
00:52:26.240 --> 00:52:28.600
Facebook, the Space Nuts podcast group, or

1381
00:52:28.600 --> 00:52:30.700
the official Space Nuts Facebook group page,

1382
00:52:30.700 --> 00:52:33.380
or Instagram. Uh, you can also visit our

1383
00:52:33.380 --> 00:52:34.820
website and have a look around while you're

1384
00:52:34.820 --> 00:52:36.660
there. Uh, maybe pick up a Christmas present

1385
00:52:36.740 --> 00:52:38.820
or two. It's coming up to that time of year,

1386
00:52:38.820 --> 00:52:40.820
and if you're not sure what to buy, if you've

1387
00:52:40.820 --> 00:52:42.260
got one of those people, you don't know what

1388
00:52:42.260 --> 00:52:44.540
to buy them. Go to our shop and see what you

1389
00:52:44.540 --> 00:52:45.060
can find.

1390
00:52:45.610 --> 00:52:48.460
Uh, that's Space Nuts IO and from

1391
00:52:48.460 --> 00:52:50.020
me, Andrew Dunkley. Thanks for your company.

1392
00:52:50.020 --> 00:52:52.140
We'll see you real soon on the next episode

1393
00:52:52.140 --> 00:52:53.620
of Space Nuts. Bye. Bye.

1394
00:52:54.900 --> 00:52:57.100
Voice Over Guy: You've been listening to the Space Nuts

1395
00:52:57.100 --> 00:53:00.050
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1396
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1397
00:53:02.170 --> 00:53:05.010
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00:53:05.010 --> 00:53:07.330
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00:53:07.330 --> 00:53:10.100
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1400
00:53:10.100 --> 00:53:12.300
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