Cosmic Questions: Time, Mass, and the Spectacle of Auroras

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

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is Space Nuts, a Q and A edition. My name is

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Andrew Dunkley. Hope you're well. Stick

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around. We have got questions from, uh,

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our audience. One about time in

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anti gravity and the speed of time.

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Uh, that's always fun to talk about.

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Uh, we've got another question about

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supernova remnants, uh, the colors

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of aurora and uh,

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a light speed boost idea. This is a. Could

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I. Would I. Should I type of with my

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spaceship do something that might give me a

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light speed boost? We'll see if it works on

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this edition of space nuts. 15

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seconds. Guidance is internal.

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Professor Fred Watson: 10, 9. Ignition

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sequence start. Uh, space nuts.

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Andrew Dunkley: 5, 4, 3.

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Professor Fred Watson: 2. 1, 2, 3, 4, 5, 5, 4,

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3, 2, 1.

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Andrew Dunkley: Space nuts. Astronauts report it feels

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good. And he's back, uh, once

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again to try and solve all your little

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riddles. Here's Professor Fred Watson,

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astronomer at large. Hello, Fred.

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Professor Fred Watson: Hello there, Andrew. It's very good to be

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talking with you. It is. I'm sorry I've

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turned into an Irishman.

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Andrew Dunkley: Because I wonder what was happening there.

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Professor Fred Watson: Yeah, I said my trip to Ireland, which is

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great.

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Andrew Dunkley: There's nothing wrong with the Irish. When we

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were there in would have been July.

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Professor Fred Watson: Yeah, July.

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Andrew Dunkley: Uh, they really bunged it on for us at

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um, a place called Cove. It used to be

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called, um, I think

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Victoria. Was that what it was called?

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Um, no, no. Uh, anyway, it's where

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the, uh, Titanic, uh, made its last

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stop before heading out to the Atlantic and

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picked up its last groups of passengers. And

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some very sad stories as well. Uh,

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yeah, the pier where everybody got on board,

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um, the boats to go out to the Titanic

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because it couldn't actually anchor it at

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port. Have had to anchor outside the harbor

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at, um, uh, Cove.

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Um, um,

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it's still there, parts of it.

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So you can still see the remnants of that

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old. Um. And the White Star Line

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office is still there as well, which is now a

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museum where you can learn about the Titanic

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through the Titanic experience. I highly

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recommend that in the town of COVID which is

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nearby. County Cork. County

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Cork it is, yeah. Ah, lovely place.

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And they had Australian and New Zealand flags

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everywhere and music playing and they know

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how to party, those people. Yeah, terrific.

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Uh, shall we, um, do some questions, Fred?

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Professor Fred Watson: No, no, I think we should just have a cup of

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tea.

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Andrew Dunkley: Yeah, we probably have less trouble.

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Uh, let's firstly get a question from

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Andy.

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Speaker C: Hi guys, it's Andy here from the uk,

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first time questioner. Two questions,

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both time related. Um,

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the first question,

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um, as mass and

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gravity are so closely related

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and the higher a mass is, the

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slower time will flow.

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What would happen to the flow of time in an

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anti gravity field? So that's the

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first question. Um, the

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second question. If a

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planet had life that was

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intelligent and um, was evolving

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and had the potential to become

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space faring, but the planet was

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high gravity, is the playoff between

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gravity and the speed of time

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enough that that will make a significant

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difference to the evolution of the planet

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on galactic scales? Hope that one makes

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sense. Great program, no doubt. I'll be back

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again.

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Andrew Dunkley: Wow, Andy, where. Gee whiz, you've been

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pondering that for a while. There's some

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great questions there. Um, we'll tackle the

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first one first. Unless you want to do the

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first one second and the second one, I don't

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know. Uh, time, the effect of,

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um, uh, the effect on time,

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um, if it passes through an anti gravity

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field or just the effect on time in an anti

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gravity field.

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Professor Fred Watson: Yes. So, um,

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Andy's right actually. Uh, so

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what you've got is this phenomenon called

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time dilation. Appears that clocks slow

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down when you're in a gravitational field.

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Um, they only appear to be slowed down

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to outside observers. To you as the person

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in the gravity field, it makes no difference.

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The clock's just ticking at the same speed as

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it always did. But to an outside observer,

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your clocks are ticking more slowly. Uh, if

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there was such a thing as an anti gravity

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field, and we have no knowledge of

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anything like that at the moment, although

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people have worked very hard to try and

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demonstrate anti gravity, uh, as you can

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imagine, it would be a very useful thing to

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be able to harness, um,

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um, if you could have anti gravity. In other

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words, something that uh,

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actually repelled rather than attracted. Yes,

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the, the, um, or, or at

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least no, Let me put it another way. It's not

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repel repulsion, it's reducing the

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effect of gravity. I think anti gravity

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might, might reduce the effect of gravity.

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Uh, and it could, if you reduce it beyond

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zero, it could produce a repulsion. But

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that is not, that doesn't really matter for

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this argument because what happens is,

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um. Yes, relativity says that time would

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actually speed up. Uh, time, as I

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said to the person in the anti gravity field

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would keep on ticking away as normal. But to

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the outside observer, uh, the time would

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appear to be passing more quickly.

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Andrew Dunkley: Isn't it the same effect if you are falling

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into a black hole, what you're seeing is

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happening in real time because you're living

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your life like you do anywhere. But to

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the observer you would be,

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you know, a completely different Bucket of

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fish.

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Professor Fred Watson: That's right. Time slows down. Uh, everything

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appears more slowly. And when you cross the

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event horizon, you're sort of frozen on it.

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Yeah. Which means that event horizons are

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always splattered with things that have

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fallen into the. Maybe. Yeah.

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Hard to imagine.

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Andrew Dunkley: It's like the front of a car.

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In summer.

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Professor Fred Watson: White hopped. Yes. Um,

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yep.

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Andrew Dunkley: I think this was portrayed quite well in the

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movie Interstellar, where they had to go down

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onto a planet that was under the effect of a,

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A black hole. And every hour on the planet's

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surface equated to seven years back on the

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spaceship. Um, they, they did

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portray that quite well.

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That effect.

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Professor Fred Watson: Yeah.

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Andrew Dunkley: Okay, so there's no such thing really as an

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anti gravity field, but, um,

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he'd be right. The effect would be.

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Professor Fred Watson: That's right.

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But the second part of Andy's question.

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Andrew Dunkley: Yes. Um, high levels of gravity and

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its effect on the speed of time.

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Professor Fred Watson: Well, what he's saying is, if you had a

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planet or if you had a

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civilization working in a very high

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gravitational field, uh, would that mean

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that they would evolve more quickly and

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things would develop more quickly? Um, and

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I suppose the answer is yes, but only to an

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outside observer. To the people

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doing it, it would be just the same.

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Um, so, yes, maybe if our planet had

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a hugely different gravitational field

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from what it does have. Uh, seen from the

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outside, we might look as though we're

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evolving more quickly and developing

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technology more quickly, but to

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us, it would be just the same as if we had,

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you know, a lower gravitational field.

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Andrew Dunkley: This would complicate the search for

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intelligent life, wouldn't it? Uh, I mean,

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you might find a planet, um, and go,

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hey, something's going on there. Um,

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but it's in, it's in a, you know, high

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gravity environment. And, um,

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maybe it was happening

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some time ago, but it's all over. Red Rover.

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I mean, I don't know, it's. It's a head

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scratcher.

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Professor Fred Watson: Or.

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Andrew Dunkley: Here's one. If you do find a civilization

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living in a, in a, on a planet and, uh, you

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land to say hello, and then you take off

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again and find out that everyone at home's

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dead because you've been gone 500 years, but

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you were only gone a week.

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Professor Fred Watson: Yeah. Well, there's that, too. That's right.

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Yeah. That's, um, special relativity. That's,

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uh, the.

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Andrew Dunkley: That's the one.

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Professor Fred Watson: The relativistic difference in time. Well,

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because you're traveling at speeds near the

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speed of light. Yeah.

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Andrew Dunkley: I mean, it happens. Happens. On Earth,

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they've done those tests with, um, highly

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sensitive clocks and tested them at

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different altitudes and they've come back

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and went, well, look, there's a thousandth of

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a second difference in their performance. So

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we've moved through time. I read a story the

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other day, Fred, which I wish I'd kept it,

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um, about a cosmonaut, I think it was, who'd

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spent so much time in space that they

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estimated that, um,

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he was actually slightly ahead of time

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than everybody else. And I can't

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remember the details, but, uh, it was really

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fascinating.

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Professor Fred Watson: Um.

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Andrew Dunkley: They'Ve released a paper about it. I'll see

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if I can find it interesting. I might do

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that while you answer this next question.

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Thank you, Andy. I love that idea though. Um,

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keep them coming.

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Three, two, one.

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Speaker C: Space nuts.

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Andrew Dunkley: Uh, this question comes from Mark. Hi, Andrew

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and Fred and team. My name is Mark Turner

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and I live in the south of England. I'm sorry

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about that. About five, about five minutes

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from Patrick Moore's house as a point of

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interest. Wow. Um, I've been

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listening now for just over three years and

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always look forward to Thursday lunchtime

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when I sit down and listen to you guys.

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Sorry, we were talking about toilet stuff

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earlier. I hope that didn't mess you up. Uh,

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my question is, it's generally accepted

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that all of the heavy elements were produced

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in an even larger star than ours that

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went supernova. Which leads me, uh, to this.

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Can we still see the remains of the star

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that made us in the night sky,

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or do we know, uh, at what point in the

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night sky the star would have been by turning

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back the cosmic time clock? Keep up the great

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work, Mark.

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What do you reckon about that one?

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Professor Fred Watson: Um, so the answer is no.

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Um, because.

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So, yes, um, uh,

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what we call the interstellar medium, the gas

261
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between the stars, is enriched

262
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in its chemical, um,

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abundance. The amount of heavier elements

264
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that are in it enriched over time because

265
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of supernova explosions.

266
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Stars that have detonated and

267
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gone through this high temperature process

268
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where you get heavier elements created. And

269
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some of the heavy elements we now know are

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created in neutron star collisions,

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um, but that doesn't matter which

272
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it is. Um, the bottom line is that

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it's the general interstellar

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medium that is enriched. So you've got an

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explosion that takes place and over

276
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millions of years, the debris from

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that explosion just gets absorbed into

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the clouds of gas and dust that are then

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going to form, uh, later generations of

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stars. So there's really no way

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that the remnants of the star that gave

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us. Uh,

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the heavier elements, um, there's

284
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no way that we can pinpoint

285
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that it may be that some of the

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supernova remnants that we see, and we see

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many around the sky, that some of those

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were responsible for some of the

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stuff.

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They were probably responsible for enriching

291
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the interstellar medium closer to them than

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we are. That's kind of the point, I guess, I

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want to make. The debris that gave us

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our enriched interstellar medium

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is probably long dissipated. And we could

296
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not identify, uh, it with any of

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the known supernova remnants because

298
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they're still enriching their local

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environment, if I can put it that way,

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because they're still intact structures.

301
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They're expanding and dissipating, but we see

302
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them as intact structures. And so the

303
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debris that made us 4.6

304
00:12:53.930 --> 00:12:56.100
billion years ago is, uh,

305
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basically is nowhere near. You know,

306
00:12:59.690 --> 00:13:01.250
it's nothing to do with them.

307
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Um, and partly because those explosions took

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place more recently than the 4.6 billion

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years ago origin of our own solar system.

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So, uh, the.

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Basically, uh, yes, the answer is,

312
00:13:16.690 --> 00:13:19.650
well, no, we can't identify those

313
00:13:19.650 --> 00:13:22.530
remains. Uh, and turning back the cosmic time

314
00:13:22.530 --> 00:13:25.530
clock, we can do that, but we can't do it in

315
00:13:25.530 --> 00:13:27.490
the sort of detail. I mean, we can do it in a

316
00:13:28.370 --> 00:13:30.330
physical modeling sense. We're not looking at

317
00:13:30.330 --> 00:13:32.490
anything unless we're looking at things at

318
00:13:32.490 --> 00:13:34.450
great distances where we are looking back in

319
00:13:34.450 --> 00:13:37.250
time. Uh, but for the

320
00:13:37.410 --> 00:13:39.730
physics that we use to model the universe,

321
00:13:40.150 --> 00:13:43.010
um, we can't, um, wind back the clock

322
00:13:43.010 --> 00:13:45.800
in enough detail to see where

323
00:13:45.800 --> 00:13:48.800
these objects exploded. Uh, they may be,

324
00:13:48.880 --> 00:13:51.240
you know, many, many thousands, tens of

325
00:13:51.240 --> 00:13:53.680
thousands of light years away, uh, from where

326
00:13:53.680 --> 00:13:56.200
we are now. Uh, all they did was enrich the

327
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medium around them. And that's where we found

328
00:13:58.360 --> 00:14:01.199
our own, uh, solar system being formed.

329
00:14:01.199 --> 00:14:03.480
So we can't. We can't look back in time in

330
00:14:03.480 --> 00:14:06.360
that regard. Okay, thank you,

331
00:14:06.360 --> 00:14:08.760
Mark. Uh, by the way, I, uh, was a pretty

332
00:14:08.760 --> 00:14:10.950
regular visitor to Patrick Moore while, uh,

333
00:14:11.200 --> 00:14:13.160
he was still alive. So I know that house.

334
00:14:13.160 --> 00:14:15.670
Well, at Selsey, it was called Farthings, uh,

335
00:14:15.880 --> 00:14:18.830
is a lovely house, actually. Uh, and, um,

336
00:14:18.830 --> 00:14:21.000
when I used to visit him, he was always very

337
00:14:21.000 --> 00:14:23.920
welcoming, uh, and, um, always glad to show

338
00:14:23.920 --> 00:14:24.360
me around.

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Andrew Dunkley: Wonderful. Wow. Lucky you. Yeah.

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00:14:27.680 --> 00:14:28.120
Professor Fred Watson: Yeah.

341
00:14:28.360 --> 00:14:31.000
Andrew Dunkley: Now, um, just to sort of draw on

342
00:14:31.000 --> 00:14:33.920
Mark's question, um, so he's

343
00:14:33.920 --> 00:14:36.200
right about a supernova creating the heavy

344
00:14:36.200 --> 00:14:36.680
elements.

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00:14:37.320 --> 00:14:37.760
Professor Fred Watson: Yes.

346
00:14:37.760 --> 00:14:40.760
Andrew Dunkley: So how do they end up being a

347
00:14:40.760 --> 00:14:42.800
part of our planet? Is that because the

348
00:14:42.800 --> 00:14:44.360
supernovas created the.

349
00:14:45.900 --> 00:14:48.780
The spawning ground or being, you know,

350
00:14:48.940 --> 00:14:50.780
run through it? What. How does that work?

351
00:14:51.020 --> 00:14:53.180
Professor Fred Watson: Yeah, I mean, it's what I was saying.

352
00:14:53.180 --> 00:14:55.020
Basically, the, the. You Know, you get a

353
00:14:55.020 --> 00:14:57.980
supernova explosion which um,

354
00:14:57.980 --> 00:15:00.700
sends shockwaves out, uh, it sends

355
00:15:00.860 --> 00:15:03.420
enriched gas out and that gas

356
00:15:03.500 --> 00:15:06.300
gradually diffuses into the

357
00:15:06.460 --> 00:15:09.260
background, uh, what we call the

358
00:15:09.260 --> 00:15:11.380
interstellar medium. This, the, the gas

359
00:15:11.380 --> 00:15:14.060
between the stars. It's very, very rarefied,

360
00:15:14.460 --> 00:15:17.360
but that's where that stuff. And as

361
00:15:17.360 --> 00:15:20.120
you then get concentrations of that gas

362
00:15:20.440 --> 00:15:23.200
into clouds of hydrogen, mostly hydrogen, but

363
00:15:23.200 --> 00:15:25.280
other M elements as well, because it's been

364
00:15:25.280 --> 00:15:28.240
enriched, then that is what would form the

365
00:15:28.240 --> 00:15:31.120
next solar system. Uh, and so that, you

366
00:15:31.120 --> 00:15:33.880
know, that gradual process of

367
00:15:34.120 --> 00:15:36.600
uh, stars forming, exploding,

368
00:15:36.680 --> 00:15:39.560
enriching the uh, interstellar medium,

369
00:15:39.720 --> 00:15:42.600
then interstellar medium creates other star

370
00:15:42.600 --> 00:15:45.490
systems which do the same thing. It's why

371
00:15:45.490 --> 00:15:48.210
as the universe ages, you're going to get an

372
00:15:48.210 --> 00:15:50.970
enrichment of the number of heavy,

373
00:15:50.970 --> 00:15:53.050
of, you know, quantities of heavier elements

374
00:15:53.050 --> 00:15:54.690
that there are within the universe. And

375
00:15:54.690 --> 00:15:57.290
that's actually one way that we can measure

376
00:15:57.290 --> 00:16:00.010
the ages of stars, by how much of this stuff

377
00:16:00.010 --> 00:16:02.130
they've got in them. Because when they were

378
00:16:02.130 --> 00:16:03.730
formed, the universe would have been at a

379
00:16:03.730 --> 00:16:06.730
certain point of enrichment. Uh, and you

380
00:16:06.730 --> 00:16:09.730
know, that point is fossilized,

381
00:16:09.730 --> 00:16:12.600
if I can put it that way, in the star itself

382
00:16:12.680 --> 00:16:14.640
by the chemical composition that it

383
00:16:14.640 --> 00:16:15.400
demonstrates.

384
00:16:16.040 --> 00:16:18.920
Andrew Dunkley: Okay, very good. Um, it's a law

385
00:16:18.920 --> 00:16:20.760
of diminishing returns though, isn't it?

386
00:16:20.920 --> 00:16:22.560
Eventually all of this is going to stop

387
00:16:22.560 --> 00:16:23.080
happening.

388
00:16:23.160 --> 00:16:25.240
Professor Fred Watson: Yes, that's right. Eventually the universe

389
00:16:25.240 --> 00:16:27.080
will die because of that. Because there won't

390
00:16:27.080 --> 00:16:29.720
be any more. There won't be any gas

391
00:16:29.960 --> 00:16:32.440
in which to create supernova explosions,

392
00:16:32.440 --> 00:16:34.760
which is the raw material of stars, hydrogen

393
00:16:34.760 --> 00:16:37.520
gas that will all be used up eventually and

394
00:16:37.520 --> 00:16:39.490
we'll have what used to be called the heat

395
00:16:39.490 --> 00:16:41.930
death of the universe. Unless it starts

396
00:16:41.930 --> 00:16:43.250
collapsing on itself again.

397
00:16:43.490 --> 00:16:45.730
Andrew Dunkley: Well, yeah, I mean there's all these

398
00:16:46.290 --> 00:16:48.170
terrible perilous things that are going to

399
00:16:48.170 --> 00:16:51.170
happen, but um. It'S

400
00:16:51.170 --> 00:16:52.970
not going to happen next week, the week after

401
00:16:52.970 --> 00:16:55.210
maybe, because we're on holidays, if we're

402
00:16:55.210 --> 00:16:55.610
lucky.

403
00:16:55.610 --> 00:16:57.010
Professor Fred Watson: The week after. Yeah, that's right.

404
00:16:58.130 --> 00:16:59.970
Andrew Dunkley: Yeah. Thank, uh, you Mark. Great question.

405
00:17:00.130 --> 00:17:02.010
Uh, now that thing I was trying to look up, I

406
00:17:02.010 --> 00:17:04.920
can't find the exact story, but um,

407
00:17:05.180 --> 00:17:08.180
I found something that kind of explains the

408
00:17:08.180 --> 00:17:10.500
concept. Apparently, um, for a six month

409
00:17:10.500 --> 00:17:12.460
mission on the International Space Station.

410
00:17:12.460 --> 00:17:14.380
And as astronaut ages,

411
00:17:14.940 --> 00:17:17.780
0.005 seconds less than they

412
00:17:17.780 --> 00:17:20.620
would on Earth. So this, this particular

413
00:17:21.070 --> 00:17:23.580
um, ah, cosmonaut that I'm talking about

414
00:17:23.660 --> 00:17:25.820
apparently has spent so much time in space

415
00:17:26.380 --> 00:17:29.020
that he's actually, I think it's

416
00:17:29.020 --> 00:17:31.770
0.22, um,

417
00:17:32.110 --> 00:17:34.110
minutes younger than he.

418
00:17:35.870 --> 00:17:37.150
Had he drawn into space.

419
00:17:38.110 --> 00:17:40.270
Professor Fred Watson: It's only seconds rather than minutes. Yeah.

420
00:17:40.350 --> 00:17:42.830
Andrew Dunkley: Oh, 0.22 seconds. Yes, exactly.

421
00:17:43.150 --> 00:17:46.150
Yeah. Um, so I, I, yeah, I read

422
00:17:46.150 --> 00:17:48.390
it last week. I meant to send it to you and I

423
00:17:48.390 --> 00:17:50.630
completely forgot. So, uh, but that's the,

424
00:17:50.630 --> 00:17:52.590
that's the, the, the guts of the story.

425
00:17:53.870 --> 00:17:55.950
This uh, is Space Nuts. Andrew Dunkley with

426
00:17:56.030 --> 00:17:57.550
Professor Fred Watson.

427
00:17:58.460 --> 00:17:59.340
Professor Fred Watson: Space Nets.

428
00:18:00.240 --> 00:18:03.140
Andrew Dunkley: Uh, we have a, uh, question from one of

429
00:18:03.140 --> 00:18:05.580
our regular contributors. This is Casey.

430
00:18:05.740 --> 00:18:08.380
Speaker C: Hi guys. This is Casey from Colorado. Um,

431
00:18:08.620 --> 00:18:11.380
I just saw red northern lights and it

432
00:18:11.380 --> 00:18:13.420
was, it was really incredible.

433
00:18:13.900 --> 00:18:15.100
Professor Fred Watson: I, um, was hoping that you could.

434
00:18:15.100 --> 00:18:17.300
Speaker C: Please explain why auroras come in different

435
00:18:17.300 --> 00:18:20.020
colors. I hope you're both well and thanks

436
00:18:20.020 --> 00:18:20.940
for the podcast.

437
00:18:21.520 --> 00:18:23.740
Andrew Dunkley: Uh, thank you, Casey. Casey sent in a few,

438
00:18:24.150 --> 00:18:26.570
um, questions in recent times and we're more

439
00:18:26.570 --> 00:18:28.090
than happy to answer. She comes up with some

440
00:18:28.090 --> 00:18:30.490
interesting ideas. Uh, I just thought this

441
00:18:30.490 --> 00:18:32.970
was a good question to answer. Uh, I know

442
00:18:32.970 --> 00:18:35.130
we've talked about it before, but there's

443
00:18:35.130 --> 00:18:37.570
been some great auroral activity of late.

444
00:18:38.290 --> 00:18:41.050
And even in parts of

445
00:18:41.050 --> 00:18:42.970
Australia where you just don't see them, they

446
00:18:42.970 --> 00:18:45.450
have been absolutely stunning. Even as

447
00:18:45.450 --> 00:18:47.810
recently as a week or two ago, we had some

448
00:18:47.890 --> 00:18:50.810
fabulous photographs coming out of, um,

449
00:18:50.810 --> 00:18:52.780
many, many parts of southeastern Australia

450
00:18:53.740 --> 00:18:56.740
and. Prompted a

451
00:18:56.740 --> 00:18:59.340
thought in my mind that the one, the aurora

452
00:18:59.340 --> 00:19:02.140
we see here generally are pink.

453
00:19:02.940 --> 00:19:05.940
But when you see photos up in the northern

454
00:19:05.940 --> 00:19:07.300
hemisphere, when you're practically

455
00:19:07.300 --> 00:19:10.060
underneath them, they're green. Uh, and

456
00:19:10.220 --> 00:19:12.860
I'm sure the colors can vary

457
00:19:13.580 --> 00:19:16.300
into many areas. Fred,

458
00:19:16.500 --> 00:19:18.840
uh, I mean you've taken tours on these, um,

459
00:19:18.940 --> 00:19:21.140
to see these things you've seen that like

460
00:19:21.140 --> 00:19:22.220
this is boring for you.

461
00:19:22.220 --> 00:19:25.100
Professor Fred Watson: But, uh, it's never boring.

462
00:19:25.100 --> 00:19:27.300
Actually. I didn't imagine it wouldn't be

463
00:19:27.300 --> 00:19:29.140
just always spectacular. But you're

464
00:19:29.140 --> 00:19:31.680
absolutely right. So when we're up in uh,

465
00:19:32.100 --> 00:19:34.900
uh, Alta, which is far northern

466
00:19:34.900 --> 00:19:37.820
Norway, or um, Kirino, which is

467
00:19:37.820 --> 00:19:39.940
far northern Sweden, or Abisko, which is also

468
00:19:39.940 --> 00:19:41.780
far northern Sweden. And looking at the

469
00:19:41.780 --> 00:19:44.510
aurora, you're basically standing

470
00:19:44.510 --> 00:19:47.310
underneath it. And so you see the aurora

471
00:19:47.310 --> 00:19:50.230
as it really is. Uh, and

472
00:19:50.950 --> 00:19:53.630
you've got lots of colors in it. Um,

473
00:19:53.630 --> 00:19:56.350
but the pink and red

474
00:19:56.350 --> 00:19:58.630
aurorae are typically, uh, seen

475
00:19:59.430 --> 00:20:01.990
when you're a long way from the action.

476
00:20:02.810 --> 00:20:05.310
Uh, and the green, the bottom line is the

477
00:20:05.310 --> 00:20:05.630
green.

478
00:20:05.630 --> 00:20:08.070
Andrew Dunkley: Is we talking rate shift? No,

479
00:20:08.310 --> 00:20:10.630
no, but we're talking atmospheric.

480
00:20:12.190 --> 00:20:12.260
Uh.

481
00:20:12.600 --> 00:20:15.480
Professor Fred Watson: We'Re talking emission line spectroscopy.

482
00:20:16.680 --> 00:20:17.800
Andrew Dunkley: I never would have thought about.

483
00:20:18.040 --> 00:20:20.960
Professor Fred Watson: Yeah, so, um, the pink

484
00:20:20.960 --> 00:20:23.480
and red aurorae, uh, you'd see them

485
00:20:23.720 --> 00:20:25.240
if you're in the northern hemisphere. You'd

486
00:20:25.240 --> 00:20:27.160
see them on the northern horizon in the

487
00:20:27.160 --> 00:20:29.320
southern hemisphere here in Tasmania, you see

488
00:20:29.320 --> 00:20:32.160
them very often down in the south Usually the

489
00:20:32.160 --> 00:20:34.040
green part is below the horizon.

490
00:20:35.000 --> 00:20:37.200
It's too far over the Earth's curvature to

491
00:20:37.200 --> 00:20:40.180
see. And that's why you only see the red. And

492
00:20:40.180 --> 00:20:43.140
that's a clue to what's happening here. So,

493
00:20:43.180 --> 00:20:45.300
um, what you've got is the

494
00:20:45.540 --> 00:20:47.860
atmosphere, uh, being excited

495
00:20:48.340 --> 00:20:50.500
by radiation from the sun.

496
00:20:51.880 --> 00:20:54.820
Um, these subatomic particles charge

497
00:20:55.060 --> 00:20:57.140
out from the sun. If you've got a solar flare

498
00:20:57.140 --> 00:20:59.180
or something like that. They going at

499
00:20:59.180 --> 00:21:01.710
typically a million kilometers an hour. Uh,

500
00:21:01.860 --> 00:21:04.100
so they take a couple of days to get here.

501
00:21:04.340 --> 00:21:06.960
And then they're sort of funneled down the

502
00:21:06.960 --> 00:21:09.720
Earth's, uh, magnetic field lines. Um, and

503
00:21:09.720 --> 00:21:11.840
they're most concentrated near the magnetic

504
00:21:11.840 --> 00:21:13.840
poles. Which is why it's around the magnetic

505
00:21:13.840 --> 00:21:16.120
poles that you see most aurora. This is a

506
00:21:16.120 --> 00:21:18.720
sort of simplified version of the story. But,

507
00:21:18.760 --> 00:21:21.120
um, what happens is these electrons,

508
00:21:21.760 --> 00:21:23.320
they're accelerated. They're quite high

509
00:21:23.320 --> 00:21:25.920
energy. They hit atoms

510
00:21:26.000 --> 00:21:28.920
of oxygen and nitrogen in

511
00:21:28.920 --> 00:21:30.920
the Earth's atmosphere and they make them

512
00:21:30.920 --> 00:21:33.600
glow. And the important

513
00:21:33.680 --> 00:21:35.280
thing here is that those

514
00:21:36.340 --> 00:21:38.580
atoms of oxygen and nitrogen, actually

515
00:21:38.580 --> 00:21:41.460
they're molecules as well. Uh, O2,

516
00:21:41.460 --> 00:21:44.060
which is a pair of oxygen atoms, or N2, which

517
00:21:44.060 --> 00:21:47.020
is a pair of nitrogen atoms. Um, they behave

518
00:21:47.020 --> 00:21:49.660
differently at different pressures. And of

519
00:21:49.660 --> 00:21:51.260
course, as you go up through the atmosphere,

520
00:21:51.260 --> 00:21:54.260
the pressure gets steadily lower. So the most

521
00:21:54.260 --> 00:21:57.060
common one is the green light. And

522
00:21:57.060 --> 00:21:59.540
that's, uh, when you've got

523
00:21:59.780 --> 00:22:02.510
oxygen burn. Being excited to emit

524
00:22:02.510 --> 00:22:04.710
this green color. It's what we call a

525
00:22:04.710 --> 00:22:06.790
spectrum line. It's a particular wavelength,

526
00:22:06.790 --> 00:22:09.070
which means it's a particular color. Uh, but

527
00:22:09.070 --> 00:22:11.690
it's green. Uh, and that, uh,

528
00:22:11.710 --> 00:22:14.470
works for pressures that you see

529
00:22:14.470 --> 00:22:16.510
between about 100 and 200

530
00:22:16.910 --> 00:22:19.310
kilometers above the Earth's atmosphere.

531
00:22:20.110 --> 00:22:22.670
Above 200 kilometers, the

532
00:22:22.670 --> 00:22:25.470
pressure is lower, uh, and

533
00:22:25.790 --> 00:22:27.750
the green line doesn't form, or the green

534
00:22:27.750 --> 00:22:30.060
light is not formed. Uh, it's actually

535
00:22:30.060 --> 00:22:33.020
quenched. And there is a different atomic

536
00:22:33.020 --> 00:22:35.860
process that gives rise to red light.

537
00:22:37.110 --> 00:22:39.860
Uh, 630 nanometers, if I remember rightly,

538
00:22:40.100 --> 00:22:42.340
is the wavelength. So you get this red light,

539
00:22:42.580 --> 00:22:45.580
which is still oxygen, but it's oxygen at

540
00:22:45.580 --> 00:22:48.420
a lower pressure than what comes out

541
00:22:48.420 --> 00:22:50.740
from the green. So between 1 and 200

542
00:22:50.740 --> 00:22:52.660
kilometers, you're going to see green aurora.

543
00:22:52.660 --> 00:22:54.660
Above that, you're going to see red aurorae.

544
00:22:54.660 --> 00:22:57.420
And that's why we only see the red ones. If

545
00:22:57.420 --> 00:22:58.940
you're looking from Australia, because the

546
00:22:58.940 --> 00:23:01.860
green is way below the horizon. Um,

547
00:23:01.860 --> 00:23:04.820
if you've got a really, um, powerful

548
00:23:05.380 --> 00:23:08.220
stream of subatomic particles, then

549
00:23:08.220 --> 00:23:10.900
they will penetrate below 100km.

550
00:23:11.220 --> 00:23:14.220
And that then excites not

551
00:23:14.220 --> 00:23:16.710
the oxygen, but the Nitrogen. You get um,

552
00:23:16.740 --> 00:23:19.180
what's called molecular excitation. Nitrogen

553
00:23:19.180 --> 00:23:21.900
molecules start emitting light and they

554
00:23:21.900 --> 00:23:24.260
emit in several different colors. Light,

555
00:23:24.740 --> 00:23:27.710
um, deep blue, um, there is

556
00:23:28.110 --> 00:23:30.740
different red, there's sort of greens, uh,

557
00:23:30.740 --> 00:23:32.590
and all those mixed together to give you

558
00:23:32.590 --> 00:23:35.310
something like a purple. Often in a bright

559
00:23:35.310 --> 00:23:37.950
aurora you've got the green auroral curtains

560
00:23:38.030 --> 00:23:40.510
and below that there might be a purple layer

561
00:23:40.510 --> 00:23:42.950
as well. And sometimes the colors are so

562
00:23:42.950 --> 00:23:45.150
mixed that it turns white that you actually

563
00:23:45.150 --> 00:23:47.910
get a white bottom edge to an aurora. Then

564
00:23:47.910 --> 00:23:50.190
you know, you've got really high energy

565
00:23:50.270 --> 00:23:52.230
electrons and then you saw all.

566
00:23:52.230 --> 00:23:53.150
Andrew Dunkley: You see in one of those.

567
00:23:53.510 --> 00:23:56.310
Professor Fred Watson: Yes, I have. Uh, yeah, actually the very

568
00:23:56.310 --> 00:23:57.950
first time we went up there, I've got

569
00:23:57.950 --> 00:23:59.590
photographs taken from a place called

570
00:23:59.590 --> 00:24:02.350
Lingenfjord in northern Norway. A very dark

571
00:24:02.350 --> 00:24:04.190
site. It was a wonderful place to see the

572
00:24:04.190 --> 00:24:06.190
aurora from. And yeah, there were definitely

573
00:24:06.190 --> 00:24:09.070
white, white, white bottoms on my auroral

574
00:24:09.070 --> 00:24:11.830
curve. Um, so

575
00:24:12.000 --> 00:24:14.750
uh, but what I was going to say

576
00:24:14.750 --> 00:24:17.710
was that's the basic story. But in

577
00:24:17.710 --> 00:24:20.070
reality you get these things all mixing and

578
00:24:20.070 --> 00:24:21.990
so sometimes you do get pinks and you get,

579
00:24:21.990 --> 00:24:23.990
you can actually get some quite odd colors.

580
00:24:25.410 --> 00:24:27.570
Actually I took some photographs at the

581
00:24:27.570 --> 00:24:30.290
beginning of this year in uh, far, again far

582
00:24:30.290 --> 00:24:32.930
northern Norway, uh, and later in Greenland

583
00:24:32.930 --> 00:24:35.210
where the coloring was almost like a brown

584
00:24:35.210 --> 00:24:37.810
color rather than the reddish that you expect

585
00:24:38.190 --> 00:24:41.130
uh, from high altitude aurora. So it's the

586
00:24:41.130 --> 00:24:42.770
way the colors mix that give you the

587
00:24:43.170 --> 00:24:45.530
different effects. Plus you've got to add to

588
00:24:45.530 --> 00:24:47.890
that the color response of your camera as

589
00:24:47.890 --> 00:24:50.530
well, which can sometimes tell you

590
00:24:50.890 --> 00:24:53.140
um, you know, give you falsehoods. Because

591
00:24:53.140 --> 00:24:56.100
the, the camera itself is, is basically

592
00:24:56.100 --> 00:24:58.420
tuned to take photographs of everyday

593
00:24:58.420 --> 00:25:00.260
objects. It's not really tuned to take

594
00:25:00.260 --> 00:25:02.380
photographs of things that are emitting only

595
00:25:02.380 --> 00:25:05.020
on one wavelength, uh, which the aurora does.

596
00:25:05.260 --> 00:25:08.140
Andrew Dunkley: Yes, yes, I know. Um, although while we were

597
00:25:08.140 --> 00:25:10.460
uh, up there, um, northern,

598
00:25:11.100 --> 00:25:13.400
northern parts of Europe, Norway, um,

599
00:25:13.420 --> 00:25:16.020
Greenland, Iceland, people, um,

600
00:25:16.260 --> 00:25:18.870
did try to um, take photos of

601
00:25:18.870 --> 00:25:20.750
aurora and a couple of them were successful.

602
00:25:21.230 --> 00:25:23.950
I was not. Yeah, I'll say

603
00:25:23.950 --> 00:25:24.270
one.

604
00:25:24.430 --> 00:25:27.230
Professor Fred Watson: But it was summer. Yes, summer's the, that's

605
00:25:27.230 --> 00:25:28.470
the problem because there's still so much

606
00:25:28.470 --> 00:25:31.270
twilight there. Um, I used to

607
00:25:31.270 --> 00:25:34.110
cut around a digital, proper digital

608
00:25:34.190 --> 00:25:36.670
camera with me and a tripod to do all these

609
00:25:36.670 --> 00:25:38.790
long exposure photographs. But to be honest,

610
00:25:38.790 --> 00:25:41.750
now with a smartphone they are so sensitive

611
00:25:41.750 --> 00:25:44.540
you can hand hold them and get really

612
00:25:44.860 --> 00:25:46.940
fantastic auroral photographs.

613
00:25:47.110 --> 00:25:49.700
Um, which blew me away the first time I did

614
00:25:49.700 --> 00:25:52.140
it, which was the beginning of this year.

615
00:25:52.750 --> 00:25:55.020
Uh, I tried it a little bit on the previous

616
00:25:55.180 --> 00:25:57.300
trip that we had up to northern parts which

617
00:25:57.300 --> 00:26:00.060
was in Canada, actually. Uh, but this time at

618
00:26:00.060 --> 00:26:01.500
the beginning of this year, in Norway,

619
00:26:01.500 --> 00:26:04.220
Sweden, Iceland, uh, and Greenland. I just

620
00:26:04.220 --> 00:26:06.980
held the smartphone up and, well, I've

621
00:26:06.980 --> 00:26:08.980
got more photographs than I know what to do

622
00:26:08.980 --> 00:26:11.470
with, and they're all dramatically good. Uh,

623
00:26:11.470 --> 00:26:13.740
the smartphone is such amazing technology.

624
00:26:14.400 --> 00:26:17.150
Andrew Dunkley: It's changed the world. Has in many ways, uh,

625
00:26:17.150 --> 00:26:18.870
particularly when it comes to photography.

626
00:26:18.870 --> 00:26:21.600
Um, it was the old, um, the old

627
00:26:21.680 --> 00:26:23.760
Canon Snappies and all those that we used to

628
00:26:23.760 --> 00:26:26.120
have with film in them. You got one shot at

629
00:26:26.120 --> 00:26:27.720
it and you didn't find out if it was any good

630
00:26:27.720 --> 00:26:28.640
for a couple of weeks.

631
00:26:28.800 --> 00:26:31.080
Professor Fred Watson: Yeah, the odds are that it, it wouldn't be

632
00:26:31.080 --> 00:26:33.400
because this sensitivity of film is so much

633
00:26:33.400 --> 00:26:35.960
lower than the, you know, than the sensors

634
00:26:35.960 --> 00:26:38.000
that we now use for images. That's the bottom

635
00:26:38.000 --> 00:26:38.840
line. Yep. Yeah.

636
00:26:38.840 --> 00:26:40.800
Andrew Dunkley: The gears are good now. Makes. Makes

637
00:26:40.800 --> 00:26:43.090
everybody a professional. Well, not quite,

638
00:26:43.090 --> 00:26:43.810
but you know what I'm saying.

639
00:26:43.810 --> 00:26:45.410
Professor Fred Watson: Talk to a professional photographer. And they

640
00:26:45.410 --> 00:26:46.490
won't actually agree with that?

641
00:26:46.490 --> 00:26:48.410
Andrew Dunkley: No, they would. They work out.

642
00:26:49.480 --> 00:26:51.690
Uh, thank you, Casey. Great question and

643
00:26:51.850 --> 00:26:54.050
good, uh, to hear from you again. Okay, we

644
00:26:54.050 --> 00:26:56.170
checked all four systems, and being with a

645
00:26:56.170 --> 00:26:58.970
girl, space nuts, our final question today.

646
00:26:59.340 --> 00:27:02.010
Uh, hi, guys, love the show,

647
00:27:02.010 --> 00:27:04.330
etc. Etc. He doesn't bandy around

648
00:27:04.730 --> 00:27:07.450
much. He's straight to the point. Uh, an idea

649
00:27:07.450 --> 00:27:09.930
just occurred to me. Uh, mass increases

650
00:27:10.170 --> 00:27:13.040
the faster you go, becoming infinite

651
00:27:13.040 --> 00:27:16.000
at the speed of light. So if it were possible

652
00:27:16.080 --> 00:27:18.920
to accelerate particles up to a

653
00:27:18.920 --> 00:27:20.960
relativistic. I hate that word.

654
00:27:20.960 --> 00:27:23.960
Relativistic speeds in some compact

655
00:27:23.960 --> 00:27:26.560
device and then throw them out of the back of

656
00:27:26.560 --> 00:27:29.280
a spacecraft, would the acceleration increase

657
00:27:29.840 --> 00:27:32.800
because you're throwing more mass out

658
00:27:32.800 --> 00:27:35.160
the back? Yeah, I did that the other day.

659
00:27:35.160 --> 00:27:38.040
It's not pleasant. Uh, kind of

660
00:27:38.040 --> 00:27:40.600
an ion engine on. On

661
00:27:40.600 --> 00:27:43.520
steroids. Uh, I'm envisioning some kind

662
00:27:43.520 --> 00:27:46.000
of small particle accelerator powered by a

663
00:27:46.000 --> 00:27:48.480
nuclear power source, preferably fission.

664
00:27:49.040 --> 00:27:51.120
Any thoughts? Absolutely. Welcome.

665
00:27:51.680 --> 00:27:51.740
Speaker C: Many.

666
00:27:51.740 --> 00:27:53.760
Andrew Dunkley: Uh, thanks, and keep up the great work. Lee

667
00:27:53.760 --> 00:27:56.720
in Sweden, not to be confused with Swede in

668
00:27:56.720 --> 00:27:57.360
Leighton.

669
00:27:59.440 --> 00:28:00.320
Professor Fred Watson: Oh, okay.

670
00:28:00.400 --> 00:28:01.200
Speaker C: Really? Yeah.

671
00:28:01.840 --> 00:28:04.340
Andrew Dunkley: That's somebody else. Um,

672
00:28:05.280 --> 00:28:07.920
no, Lee in Sweden. So, um,

673
00:28:08.100 --> 00:28:10.540
okay, so he's got a particle accelerator on

674
00:28:10.540 --> 00:28:13.540
his spaceship, and he's accelerating

675
00:28:13.540 --> 00:28:16.300
the particles up to relativistic

676
00:28:16.300 --> 00:28:19.180
speeds and then he's shooting them

677
00:28:19.180 --> 00:28:21.860
out the back of the spacecraft. Bigger mass,

678
00:28:22.020 --> 00:28:24.740
whatever. Can it accelerate the spacecraft?

679
00:28:26.520 --> 00:28:27.380
Professor Fred Watson: Um, yeah.

680
00:28:27.540 --> 00:28:29.820
All right, I'm going to read, uh, what I've

681
00:28:29.820 --> 00:28:32.660
just brought up on the screen in front of me.

682
00:28:33.540 --> 00:28:36.210
Um, relativistic mass ejection in

683
00:28:36.210 --> 00:28:38.690
ion motors is not a current technology, but a

684
00:28:38.690 --> 00:28:40.970
theoretical concept. For future propulsion,

685
00:28:40.970 --> 00:28:43.850
where ions would be accelerated to speeds

686
00:28:43.850 --> 00:28:45.410
approaching the speed of light. The

687
00:28:45.410 --> 00:28:47.970
relativistic aspect refers to the effect of

688
00:28:47.970 --> 00:28:50.490
special relativity, where an object's mass

689
00:28:50.490 --> 00:28:52.690
appears to increase as it approaches the

690
00:28:52.690 --> 00:28:54.530
speed of light, making it harder to

691
00:28:54.530 --> 00:28:56.930
accelerate it further. This would require

692
00:28:56.930 --> 00:28:59.050
extremely high energy inputs and would

693
00:28:59.050 --> 00:29:02.010
involve complex physics. Unlike current ion

694
00:29:02.010 --> 00:29:04.820
thrusters that use less energetic but still

695
00:29:04.820 --> 00:29:07.740
very high ion, uh, ejection velocities

696
00:29:08.140 --> 00:29:10.620
that came from A.I. so how's that?

697
00:29:10.780 --> 00:29:12.300
Andrew Dunkley: Yeah, well, I mean,

698
00:29:13.340 --> 00:29:14.940
A.I. can be very useful.

699
00:29:15.500 --> 00:29:17.460
Professor Fred Watson: Yeah, that's kind of what I steer.

700
00:29:17.460 --> 00:29:19.820
Andrew Dunkley: You up the wrong path. It kept getting done.

701
00:29:19.820 --> 00:29:20.219
Professor Fred Watson: Yeah.

702
00:29:20.219 --> 00:29:22.140
Andrew Dunkley: Like, I had to make some pretty significant

703
00:29:22.300 --> 00:29:25.180
inquiries last, uh, last

704
00:29:25.180 --> 00:29:27.820
year, early this year, whatever, uh, about a

705
00:29:27.820 --> 00:29:30.820
housing situation, and it just got it

706
00:29:30.820 --> 00:29:33.740
so wrong constantly. Yeah,

707
00:29:33.740 --> 00:29:36.620
um. But. Yeah, um.

708
00:29:37.000 --> 00:29:39.600
Professor Fred Watson: So what I've just read out is putting nicely

709
00:29:39.600 --> 00:29:42.600
into words what I was going to say, but

710
00:29:43.000 --> 00:29:45.120
it's putting it rather more nicely than I

711
00:29:45.120 --> 00:29:47.160
would have put it. So there you go. Yeah.

712
00:29:47.240 --> 00:29:49.880
Andrew Dunkley: All right. So the. The

713
00:29:50.440 --> 00:29:53.240
concept of, um, creating

714
00:29:53.240 --> 00:29:56.120
engines that can do these

715
00:29:56.120 --> 00:29:58.780
kinds of things is real in science,

716
00:29:58.860 --> 00:30:00.620
but only to a certain degree.

717
00:30:00.860 --> 00:30:03.510
Professor Fred Watson: Yeah, My only worry about it would be, um,

718
00:30:03.980 --> 00:30:06.020
and I guess this is what, you know, the

719
00:30:06.020 --> 00:30:07.420
complex physics bit was.

720
00:30:08.720 --> 00:30:11.500
Um, you've got different reference frames.

721
00:30:11.500 --> 00:30:13.940
You've got the reference frame of the. Of the

722
00:30:13.940 --> 00:30:16.180
spacecraft, You've got the reference frame of

723
00:30:16.180 --> 00:30:18.900
the flow of, uh, charged

724
00:30:18.900 --> 00:30:20.500
particles coming out the back of it, and

725
00:30:20.500 --> 00:30:23.260
you've got a stationary reference frame, and

726
00:30:23.260 --> 00:30:26.250
the mass looks different to all of those. Uh,

727
00:30:26.590 --> 00:30:29.150
so, uh, that will be my only

728
00:30:29.230 --> 00:30:31.070
worry about that. And it's the thing that I

729
00:30:31.070 --> 00:30:32.950
would like to go a bit further into it rather

730
00:30:32.950 --> 00:30:35.310
than rely on A.I. uh, but

731
00:30:36.350 --> 00:30:38.990
the basic principle, I think, is quite right.

732
00:30:39.570 --> 00:30:42.510
Uh, but I have a

733
00:30:42.510 --> 00:30:44.630
caveat about just watch out for your

734
00:30:44.630 --> 00:30:46.510
reference frame, if I can put it that way.

735
00:30:46.830 --> 00:30:49.670
Andrew Dunkley: Yeah. Um, I've been toying

736
00:30:49.670 --> 00:30:51.950
with AI just to, uh, sort of get some

737
00:30:51.950 --> 00:30:54.540
concepts in my head about. You know, I

738
00:30:54.620 --> 00:30:56.300
mentioned. I don't know if it was this

739
00:30:56.300 --> 00:30:58.650
podcast or the previous one where we, uh,

740
00:30:58.650 --> 00:31:00.450
where I'm writing a new book, but, um.

741
00:31:02.140 --> 00:31:04.140
I. There's some concepts I wanted to

742
00:31:04.940 --> 00:31:07.580
include, but my brain wouldn't go there.

743
00:31:07.740 --> 00:31:10.060
So, um, I did use AI to try and

744
00:31:10.460 --> 00:31:13.180
learn what I needed to learn to make

745
00:31:13.180 --> 00:31:16.100
the. The thing work the way I wanted to in

746
00:31:16.100 --> 00:31:18.500
the story. Uh, it's very clever when you want

747
00:31:18.500 --> 00:31:19.500
to do things like that.

748
00:31:20.200 --> 00:31:20.760
Professor Fred Watson: Did it help?

749
00:31:21.080 --> 00:31:22.120
Andrew Dunkley: Yeah, very much.

750
00:31:22.200 --> 00:31:22.960
Professor Fred Watson: That's interesting.

751
00:31:22.960 --> 00:31:25.880
Andrew Dunkley: Yeah. Um, in fact, it

752
00:31:26.120 --> 00:31:28.960
sometimes gave me way too many concepts. I

753
00:31:28.960 --> 00:31:31.080
only wanted one, but it gave me 10. And I'm

754
00:31:31.080 --> 00:31:34.080
thinking, oh, hang on, that's all good

755
00:31:34.080 --> 00:31:36.600
stuff. I can't use it all, so I had to pick.

756
00:31:37.000 --> 00:31:38.580
But um.

757
00:31:40.120 --> 00:31:43.040
I found it very useful. But um, if you use

758
00:31:43.040 --> 00:31:45.840
it the right way, it's a great tool. Uh,

759
00:31:45.870 --> 00:31:48.870
but if, um, for general

760
00:31:48.870 --> 00:31:51.870
information, sometimes it can just hit the.

761
00:31:52.670 --> 00:31:55.030
You're throwing a dart and hitting that metal

762
00:31:55.030 --> 00:31:55.950
thing around the edge.

763
00:31:56.030 --> 00:31:57.230
Professor Fred Watson: All right, okay.

764
00:31:57.310 --> 00:31:59.790
Andrew Dunkley: Because it's throwing information back at you

765
00:31:59.790 --> 00:32:02.350
that's too generic, I suppose.

766
00:32:02.510 --> 00:32:03.070
Professor Fred Watson: Yeah.

767
00:32:03.950 --> 00:32:06.910
Andrew Dunkley: Sometimes I uh, think when it comes to AI,

768
00:32:07.070 --> 00:32:09.510
you've got to know how to use it to get the

769
00:32:09.510 --> 00:32:10.350
best out of it.

770
00:32:11.000 --> 00:32:12.670
Professor Fred Watson: Otherwise maybe that's right. Yes. Mhm.

771
00:32:13.320 --> 00:32:14.600
Otherwise it's dangerous.

772
00:32:14.680 --> 00:32:17.480
Andrew Dunkley: Yeah. Absolutely

773
00:32:17.480 --> 00:32:20.280
true. Yeah. I have found it very handy

774
00:32:20.280 --> 00:32:23.160
for like I, I've had a few photos over

775
00:32:23.160 --> 00:32:24.760
the years that I've wanted to keep, but

776
00:32:24.760 --> 00:32:27.240
they've, they've not been really good photos

777
00:32:27.720 --> 00:32:29.760
and it's been really good at cleaning them

778
00:32:29.760 --> 00:32:32.450
up. Taking, taking out some of the um,

779
00:32:32.600 --> 00:32:34.840
this one particular photo that I really love.

780
00:32:35.080 --> 00:32:36.520
But it's, it's grainy.

781
00:32:37.100 --> 00:32:37.420
Professor Fred Watson: Yeah.

782
00:32:37.580 --> 00:32:40.420
Andrew Dunkley: So you just upload the photo and say, can

783
00:32:40.420 --> 00:32:43.380
you um. I can't remember the terminology I

784
00:32:43.380 --> 00:32:46.300
used, but can um, you do this? And it

785
00:32:46.380 --> 00:32:48.460
takes like a minute or two to

786
00:32:49.500 --> 00:32:52.500
re. Calibrate the photo and then it gives

787
00:32:52.500 --> 00:32:55.340
you its result. And uh, I

788
00:32:55.340 --> 00:32:57.690
had a couple of big hits with that. That uh.

789
00:32:58.380 --> 00:32:58.740
Professor Fred Watson: Well.

790
00:32:58.740 --> 00:33:00.300
Andrew Dunkley: But I've had a couple that didn't.

791
00:33:00.700 --> 00:33:01.050
Professor Fred Watson: Yeah.

792
00:33:01.050 --> 00:33:03.820
Andrew Dunkley: Um, because the um, it had to

793
00:33:03.820 --> 00:33:06.720
try and fill in spaces because of

794
00:33:06.720 --> 00:33:09.120
the graininess of the photo and what it

795
00:33:09.120 --> 00:33:11.200
filled them in with actually changed the

796
00:33:11.200 --> 00:33:13.880
subject too much and I didn't like it, if

797
00:33:13.880 --> 00:33:16.770
that makes any sense at all. But

798
00:33:16.770 --> 00:33:19.760
um, yeah, I do find it useful. But m.

799
00:33:20.120 --> 00:33:22.280
It's not a perfect science and you've got to

800
00:33:22.280 --> 00:33:23.080
keep that in mind.

801
00:33:24.040 --> 00:33:25.720
Lee, thanks for your question. Uh, did we

802
00:33:25.720 --> 00:33:26.400
finish with Lee?

803
00:33:26.400 --> 00:33:27.400
Professor Fred Watson: I'm pretty sure we did.

804
00:33:27.400 --> 00:33:29.440
Andrew Dunkley: Yeah. Yeah. Good on you, Lee. Hope all is

805
00:33:29.440 --> 00:33:31.720
well in Sweden and I'm sure you get to see

806
00:33:32.190 --> 00:33:34.110
lots of aurorae. To you, lucky duck.

807
00:33:34.880 --> 00:33:37.390
Um, that's it, Fred. We are

808
00:33:37.390 --> 00:33:38.590
finished. Thank you.

809
00:33:40.060 --> 00:33:41.950
Professor Fred Watson: Uh, you're welcome.

810
00:33:43.630 --> 00:33:46.460
Yeah, uh, I, um, I've enjoyed um,

811
00:33:46.460 --> 00:33:48.870
going, getting my mind bent around some of

812
00:33:48.870 --> 00:33:51.630
those issues myself. So thank you Space

813
00:33:51.630 --> 00:33:53.870
Nuts listeners. You keep me on my toes.

814
00:33:54.190 --> 00:33:56.550
Andrew Dunkley: Yes, they do, don't they? If you would like

815
00:33:56.550 --> 00:33:59.070
to send us a question, you uh, can do that

816
00:33:59.480 --> 00:34:02.400
through our website, spacenutspodcast.com

817
00:34:02.400 --> 00:34:04.440
or spacenuts IO

818
00:34:05.240 --> 00:34:08.080
and you click on the AMA link at the top

819
00:34:08.080 --> 00:34:11.080
of the home page. And, uh, just fill in

820
00:34:11.080 --> 00:34:12.760
the blanks. Uh, you can send us your text

821
00:34:12.760 --> 00:34:15.520
questions that way. Or you can send us an

822
00:34:15.520 --> 00:34:18.040
audio question if you've got a device with a

823
00:34:18.040 --> 00:34:20.080
microphone. And just remember, uh, to tell us

824
00:34:20.080 --> 00:34:21.480
who you are and where you're from. Most

825
00:34:21.480 --> 00:34:24.160
people do these days. Or you can send us

826
00:34:24.160 --> 00:34:25.840
questions via YouTube Music. We've been

827
00:34:25.840 --> 00:34:27.960
getting a few of those and sometimes they

828
00:34:27.960 --> 00:34:30.200
just turn up on social media. Uh, it doesn't

829
00:34:30.200 --> 00:34:31.869
matter. We'll, um, we'll get to them.

830
00:34:31.949 --> 00:34:34.709
Although on social media, the audience

831
00:34:34.709 --> 00:34:37.310
tends to deal with them for us. Um,

832
00:34:37.469 --> 00:34:39.590
not many of them filter through, but, uh,

833
00:34:39.590 --> 00:34:42.490
yeah, keep, uh, those questions coming. Um,

834
00:34:42.509 --> 00:34:45.189
and, uh, yeah, that'll all be good, Fred.

835
00:34:45.189 --> 00:34:47.188
We'll see you next week. I think it'll be our

836
00:34:47.188 --> 00:34:49.069
last couple of programs before the Christmas

837
00:34:49.069 --> 00:34:49.389
break.

838
00:34:49.709 --> 00:34:51.309
Professor Fred Watson: May well be. That's right.

839
00:34:51.869 --> 00:34:53.309
Andrew Dunkley: All right, we'll catch you then. Thanks,

840
00:34:53.309 --> 00:34:53.709
Fred.

841
00:34:53.709 --> 00:34:54.229
Professor Fred Watson: Sounds great.

842
00:34:54.229 --> 00:34:56.349
Andrew Dunkley: And thanks to Huw in the studio, who went

843
00:34:56.349 --> 00:34:58.589
supernova on us because he's got a lot of

844
00:34:58.589 --> 00:35:00.189
heavy elements and he's gone to see a

845
00:35:00.189 --> 00:35:02.490
dietitian. And from me, Andrew Dunkley,

846
00:35:02.730 --> 00:35:04.410
thanks for your company. We'll see you on the

847
00:35:04.410 --> 00:35:05.930
next episode of Space Nuts.

848
00:35:05.930 --> 00:35:06.490
Speaker C: Bye. Bye.

849
00:35:07.150 --> 00:35:09.890
Andrew Dunkley: Uh, you'll be listening to the Space Nuts

850
00:35:09.890 --> 00:35:12.850
podcast. Available at

851
00:35:12.850 --> 00:35:14.810
Apple Podcasts, Spotify,

852
00:35:15.050 --> 00:35:17.810
iHeartRadio or your favorite podcast

853
00:35:17.810 --> 00:35:19.530
player. You can also stream on

854
00:35:19.530 --> 00:35:22.490
demand@bytes.com. this has been another

855
00:35:22.490 --> 00:35:24.530
quality podcast production from

856
00:35:24.530 --> 00:35:25.690
bytes.com.