Cosmic Collapses, Black Hole Illusions & Antimatter Mysteries

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Andrew Dunkley: Hi there. Welcome to a Q and A edition of

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Space Nuts. My name is Andrew Dunkley, your

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host. Good to have your company again. Uh,

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questions coming today from Pete. Uh, he's

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looking at the collapse of the universe.

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Wants to know where he needs to be when it

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happens, so he gets a good view. Actually, I

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think it's about something else. Uh, we've

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also got a question from Tad, who has

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brought up a really interesting point about

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falling into a black hole. From an observer's

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perspective. If we were to watch someone or

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something do, uh, really is a.

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A great piece of science to talk about. Uh,

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Mark is, uh, bringing up something from an

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episode four years ago, I think. Antimatter,

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uh, stars. And Dave, um,

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wants to know about the best time and place

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to aim a camera for low, uh, light

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astrophotography. Uh, that

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is a great question. Uh, I've had so much

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trouble with that myself. We'll get stuck

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into it right now on this edition of space

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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, 3.

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

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3, 2, 1. Space nuts. Astronauts

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report it feels good.

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Andrew Dunkley: And here he is again. Professor Fred Watson

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Astronomer at large. Hello, Fred

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Professor Fred Watson: Hello, Andrew. Fancy seeing you here.

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Andrew Dunkley: Yes, yes. And we're in similar coloured

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shirts today.

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Professor Fred Watson: That's right. I think we're very chic.

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Andrew Dunkley: Judy reckons green's my colour, but I've

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never really liked green. But

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anyway, she's more of a

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fashionista than I am, so I'll take her word

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for it. Uh, how you been?

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Professor Fred Watson: Very well, thank you. Yes, um, all seems to

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be going well so far.

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Andrew Dunkley: You look and sound as well as the last time I

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saw you.

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Professor Fred Watson: Well, that's right. I've, you know, uh,

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it's, uh, it's. It seems like only

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a few minutes ago. It does, doesn't it?

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Andrew Dunkley: Funny that, um. That's because of a black

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hole.

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Professor Fred Watson: It could be a black bill.

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Andrew Dunkley: Although we must point out that this will be

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your last show for a short while. You're

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taking a bit of a trip which will take, um,

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you into time zones that are just not

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compatible with life on Earth in Australia.

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So, um, uh, we will be, uh,

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bringing our, uh, stand in Jaunty Horner in

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to look after things while you're away for

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about 7ish weeks, something like that.

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We, we knew this was going to happen this

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year with me away for three months and you

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away for, uh, a couple of months. So we knew

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this was going to happen and we, we planned

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ahead so that the show could go on. So,

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um, anyway, we'll um, we'll look forward to

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chatting with, with Jonty and wish, uh, you

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well on your trip. Um, where.

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Professor Fred Watson: We'Ve got about two and a half weeks in

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Japan. Uh, then we're back in

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Australia very briefly and then we're off up

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to Ireland for a Dark sky conference and,

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uh, skipping over to the UK to hang out

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with my family for a little bit in the uk and

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uh, that'll take us to the end of November.

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Andrew Dunkley: Why wouldn't you? It's just a short hop,

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isn't it, really?

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Professor Fred Watson: Yeah, that's right. Yeah. It's stupid. Going

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to uk. That's right, yeah. So we'll do

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a few, uh, things. We're going to, uh.

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Marnie's got a nice itinerary for us. We're

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going to go to places that I have wanted to

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go ever since I was a child and never made it

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in the uk. So that's fantastic. We'll tell

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you about it when we get back.

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Andrew Dunkley: Love to hear about it. Um, we better get

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into, uh, the questions.

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Professor Fred Watson: Yes, yes.

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Andrew Dunkley: Yeah, I guess so. Yeah. Yeah.

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Our first question's an audio question

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coming, uh, from Pate Fred Watson and

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Andrew.

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Pete: Pete from Longpoint got a question.

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I know that there's

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contested as to what's going to happen in the

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future with the universe. The kind of

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dang, or however it's pronounced, or

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expansion or the Big Rip or whatever. The

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question if, if the universe is going to

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collapse back in itself. I get the concept

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of the gravity

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bringing sort of physical matter back

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together and I know that's only what, 5% of

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the universe, but I don't understand how

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that would work with

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the. Basically pulling light

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backwards. So you have light is

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expanding ever increasingly,

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obviously at the speed of light. Um,

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basically what happens with that in the event

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there is a collapse back to another

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singularity? Um, yeah, I'm

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confused. Thanks guys.

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Andrew Dunkley: I think a lot of people are, uh, um, yeah, he

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was referring to the Gnab Gib, which is the

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reverse Big Bang. Yeah. Uh, but it's

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an interesting question because if, if it

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does happen, rather than a Big Rip, uh, the,

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the universe stops expanding and then starts

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receding back in on itself. What does

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happen to the light and the dark matter

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and all that other stuff that we don't

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understand.

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Professor Fred Watson: So, um,

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uh, this. No, thanks very much,

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Pete.

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Great question. Uh, which has arisen because

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I, um, think it might be. While you were

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away, Andrew, we covered the new

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observations that have come from the dark

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energy, uh, instrument, um,

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which is on a, on a, on the

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mail telescopes, a telescope very similar to

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our Anglo Australian telescope which is uh,

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which has been surveying the universe as you

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do with such instruments, um, getting the

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redshifts, which means the distances of all

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the galaxies and building up a map. And that

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map um, has just the first hint

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that dark, the acceleration of the

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universe which we attribute to this dark

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energy, whatever it is, uh, that the

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acceleration of the universe is actually

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slowing down. It's still only a hint, it's

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not confirmed yet. But if the acceleration

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is slowing down then it does

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raise once again the possibility that we

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talked about a lot in the 1970s and 80s.

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Uh, the idea of an eventual collapse, a

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reversal of the expansion of the universe to

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a collapse. Uh, and the end product of

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that often called the Big Crunch. But we

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like the GNAB gib. That was the name that

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Brian Schmidt gave to it. It's a great name.

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So what happens in the Gnab gib? Well, um,

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it is interesting. You've got gravity taking

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over and it doesn't just

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sort of bring together

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the objects in space, it doesn't just

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collapse all the galaxies towards one place,

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it actually collapses space time with it.

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Um, because the, you know, the,

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the matter bend space. We know and that

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bending is effectively what you, what you

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would call the collapse uh, in the run

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up to the, or the run down to the Ganab gib.

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And so in a sense, uh, the light,

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uh, so, so what I'm saying is that

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um, the, the distances that, that across

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the, the distances that we measure between

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galaxies becomes less. But, but

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it's because the space time has shrunk

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basically. Uh, and so not just that

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the galaxies have got closer together.

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And that means uh, that yes, light will still

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continue to travel through space time at

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300,000 kilometres per second, but that

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space time has got less space in it.

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Um, and so the light just shrinks with the

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universe. It doesn't kind of escape or

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anything that many gazillions

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of photons that are currently traversing the

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universe and will continue to do that, uh, as

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long as things are shining and there's energy

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to provide that they will have shorter

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distances to go. Uh and we will find

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that the universe just gets smaller. As it

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gets smaller, the light goes with it and we

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end up with a bundle of stuff, uh, subatomic

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particles, including photons, particles of

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light, a whole lot of stuff that is going to

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hit an almighty singularity,

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uh, uh, which we might call the GNAB

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gib. Yeah, wow.

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Andrew Dunkley: Um, correct Me if I'm wrong, but didn't

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we talk in the past about a time where the

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universe will become dark and

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cold and there won't be

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any light?

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Professor Fred Watson: Well, um, that's right. If the universe

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continues expanding, then eventually

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there will be light there, but it won't be

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able to reach you because it'll be beyond

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your. Your horizon. Uh,

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so, uh, the light will still be going through

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the universe, but that light source will

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be receding from us, um,

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too fast for the light ever to get to us.

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So, yes, it becomes dark and dreary. Uh, but,

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yeah, light is still there.

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Andrew Dunkley: Uh, all right, there you go, Pete. Um,

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it will all be cataclysmic and horrible, and,

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uh, we'll all be a lot shorter.

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Professor Fred Watson: Every dimension.

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Andrew Dunkley: Indeed, yes. Although I'm starting to like

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the idea of a big rip. Because a big rip

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might open us to another universe and we

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could all escape.

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Professor Fred Watson: Well, yeah, maybe. Well, of course, you with

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the big. The gnab gib, you could get the big

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bounce. Uh, you know, it could just bounce

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back. So you've suddenly got an expanding

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universe immediately.

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Andrew Dunkley: Yeah, it's hard to get your head around. And

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I understand why Pete feels confused, because

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it really is beyond our imagination in many

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ways, isn't it?

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Professor Fred Watson: That's right.

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Andrew Dunkley: Thanks, Pete. Great question. Hope you're

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well.

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Uh, let's go to a question from Tad.

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Uh, this one's really interesting. Uh, we

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understand that due to extreme gravitational

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time dilation, from the perspective of an

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outside observer, anyone falling into a black

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hole takes an infinite amount of time to

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cross the event horizon, even if, from that

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person's perspective, they actually do in

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real time. Uh, if this is true, how

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do black holes and their event horizons even

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form in the first place, from an outsider's

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perspective? And does this mean that

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technically nothing has ever fallen into a

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black hole from our perspective here on

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Earth? I love this question. Thank you, Tad.

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Uh, he's bringing up the point

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where if you're watching someone fall into

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the. Into a black hole because of

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the. The effect, the gravitational effect on

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time space, it never happens,

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but that person

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experiences it in real time until they get

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spaghettified. So, um,

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yeah. How come we see black holes

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when this effect should

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suggest we. We should never see it happen?

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Is that. Is that what I'm. Is that what he's

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saying?

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Professor Fred Watson: Yeah, yeah. How do black holes form in the

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first place?

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Andrew Dunkley: Uh.

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Professor Fred Watson: So it, uh, yes. So in that regard,

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that time dilation is a kind of optical

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illusion because the thing has crossed the

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event horizon, whatever it is. Uh, has

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contributed to the mass of the black hole.

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So, uh, the reality is, yes,

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you're, you know, if it's you, you get

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spaghettified and then you get absorbed by

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the black hole itself a gazillionth of a

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second later. Um, it's from the outside

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perspective. Uh, I've always struggled with

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this actually in trying to envisage it

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because, yeah, you imagine some poor person

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who's fallen into a black hole. Um,

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it's be like the, um, you know those,

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uh, chalk things on the road where

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somebody's got hit by a car. There'd

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be this chalk mark of somebody, uh, on the

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surface of the event horizon.

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Um, uh, but they'd

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also, uh, uh, along with that person, there'd

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be everything else that's gone into it. And

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black holes are notorious for accreting

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material. So all the stuff that's spiralling

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into it from an outsider's perspective just

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ends up looking as though it's stuck on the

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surface of the event horizon, even though

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it's actually been absorbed by the

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black hole. So it is a kind of optical

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illusion. Yes, it's very weird. It, uh, just

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means that from, you know, what it highlights

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is, uh, it's all about your

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reference frame. Uh, our reference frame is

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an, um, observer looking out, looking in from

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the outside. If you've got the reference

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frame of the person who's falling into the

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black hole, things are a lot different. We,

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uh, can watch, um, you know, from the

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sidelines and cheer people on as they fall

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through the black hole event horizon. All,

301
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uh, we see is them frozen on the

302
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event horizon. Uh, which must be a very messy

303
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place with all the stuff that's falling into

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it.

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Andrew Dunkley: Yeah.

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Professor Fred Watson: So, um, I, yeah,

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I, you know, it to me, that transforms what

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the event horizon might look like. It's

309
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probably not that nice sphere of darkness

310
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that we imagine, but it's got splattered with

311
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lots of stuff. And in fact, we know that the

312
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magnetism of a black hole actually plays a

313
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huge role in, um,

314
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directing material so that some of the stuff

315
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is actually accelerated perpendicular to the

316
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accretion disc, uh, backward, up, upwards

317
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and downwards. And that in itself is a

318
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process. It's very hard to get your head

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around how stuff that's swirling in towards a

320
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black hole suddenly gets dragged up, uh,

321
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and shot out the poles of the

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black hole, top and bottom. Um, so a

323
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lot of hard work to conjecture. I hope that

324
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helps Tad to envisage what's going on.

325
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Uh, um, because it's all about your

326
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perspective, basically.

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Andrew Dunkley: Yeah, yeah. Uh, so the black hole,

328
00:13:40.230 --> 00:13:41.620
uh, has happened.

329
00:13:44.930 --> 00:13:47.250
My brain had an idea and it just fell into a

330
00:13:47.250 --> 00:13:49.830
black hole. Now, um, I can't remember, but,

331
00:13:49.830 --> 00:13:52.530
uh, we. We see the black hole

332
00:13:53.890 --> 00:13:56.130
because it's already happened. Is that.

333
00:13:56.770 --> 00:13:58.570
Professor Fred Watson: Well, yeah, the black. The black hole's been

334
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created in. I mean, typically in the collapse

335
00:14:01.170 --> 00:14:04.010
of a. Of a star at the end of

336
00:14:04.010 --> 00:14:06.970
its life. Uh, so that's a

337
00:14:06.970 --> 00:14:08.730
straightforward gravitational collapse. The

338
00:14:08.730 --> 00:14:11.590
material of the star, uh, basically collapses

339
00:14:11.590 --> 00:14:14.470
down so that nothing will hold it out

340
00:14:14.470 --> 00:14:16.510
and it becomes this singularity, a point of

341
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infinite density, which is how we define it.

342
00:14:19.340 --> 00:14:21.710
Um, and that's. It's during that collapse

343
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that the event horizon forms. And you've got

344
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that. As I said, it's an optical illusion.

345
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That's the main point to recognise. It's an

346
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optical illusion as seen from the outside,

347
00:14:32.600 --> 00:14:35.270
um, that nothing reaches a black hole.

348
00:14:35.920 --> 00:14:36.360
M Mm.

349
00:14:36.360 --> 00:14:38.000
Andrew Dunkley: I'm sure we'll get some more questions on

350
00:14:38.000 --> 00:14:40.400
this one, but, uh, you've probably opened a

351
00:14:40.480 --> 00:14:42.200
can of spaghetti there, Tad.

352
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Professor Fred Watson: Yeah, which is great because Jonty can deal

353
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with all of that.

354
00:14:45.360 --> 00:14:48.240
Andrew Dunkley: Yes, he can. Yeah. Yes, that's for

355
00:14:48.240 --> 00:14:48.560
sure.

356
00:14:48.960 --> 00:14:51.280
M All right, Tad. Thank you for the question.

357
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This is Space Nuts, a Q A edition with Andrew

358
00:14:53.880 --> 00:14:56.080
Dunkley and Professor Fred Watson Watson.

359
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Three, two, one.

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Space Nuts. Now, uh, our next

361
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question's an audio question. It comes

362
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from Mark.

363
00:15:08.210 --> 00:15:10.770
Mark: Hi, it's Mark in London and Canada.

364
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I just listened to an episode from

365
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March 2021 and Fred Watson mentioned the

366
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possible existence of an antimatter

367
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star and how. Obviously we wouldn't want to

368
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get, uh, anywhere near it,

369
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but I was wondering, is it. Is it possible?

370
00:15:28.490 --> 00:15:31.090
Do they exist? Uh, and how could we tell if

371
00:15:31.090 --> 00:15:33.770
we're looking at a star from Earth, can we

372
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tell if it's regular matter or antimatter

373
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or. What if the entire Andromeda Galaxy

374
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was antimatter, would we have a way of,

375
00:15:42.700 --> 00:15:43.770
uh, figuring that out?

376
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Professor Fred Watson: Thanks.

377
00:15:44.890 --> 00:15:45.370
Mark: Bye.

378
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Andrew Dunkley: M Uh, I would ask my Auntie

379
00:15:48.770 --> 00:15:51.720
Shirley, but she wouldn't know either. Um,

380
00:15:51.770 --> 00:15:54.250
thank you, Mark. Antimatter stars. We did. I

381
00:15:54.250 --> 00:15:56.450
remember us talking about them. Uh, we do

382
00:15:56.450 --> 00:15:58.010
know there is antimatter.

383
00:15:58.880 --> 00:16:00.480
Professor Fred Watson: There's just a hell of a lot.

384
00:16:00.480 --> 00:16:03.440
Andrew Dunkley: Less of it than actual matter, if I recall

385
00:16:03.440 --> 00:16:05.960
correctly. But if you've got, um, a molecule

386
00:16:05.960 --> 00:16:08.200
of matter and a molecule of antimatter and

387
00:16:08.200 --> 00:16:11.120
they collide, they just cease to exist.

388
00:16:11.120 --> 00:16:12.080
Is that how it goes?

389
00:16:13.360 --> 00:16:15.760
Professor Fred Watson: Yes, that's right, yeah. Um, what you get,

390
00:16:16.160 --> 00:16:18.720
um, is so if you. The

391
00:16:18.960 --> 00:16:21.480
difference between a normal matter

392
00:16:21.480 --> 00:16:24.400
particle, like, uh, an electron,

393
00:16:24.480 --> 00:16:27.270
and. And, uh, its antimatter equivalent

394
00:16:27.270 --> 00:16:29.750
is the electrical charge is the opposite.

395
00:16:30.310 --> 00:16:32.670
So the antimatter equivalent of an electron

396
00:16:32.670 --> 00:16:35.470
is a positron. Um, it's got positive

397
00:16:35.470 --> 00:16:37.990
electrical charge. Uh, and

398
00:16:39.110 --> 00:16:41.190
when two

399
00:16:42.150 --> 00:16:44.390
particles like that meet, they

400
00:16:44.390 --> 00:16:47.150
annihilate. And what you get is a

401
00:16:47.150 --> 00:16:49.670
gamma ray. You get a photon of gamma ray

402
00:16:49.670 --> 00:16:51.880
energy which has a uh,

403
00:16:51.950 --> 00:16:54.240
characteristic, a uh,

404
00:16:54.310 --> 00:16:56.080
characteristic frequency, um

405
00:16:56.790 --> 00:16:59.110
distribution. In gamma rays we call it

406
00:16:59.110 --> 00:17:01.110
energy. Uh, in light we think of it as

407
00:17:01.110 --> 00:17:03.070
wavelength, in radio waves we think it as

408
00:17:03.470 --> 00:17:05.830
frequency. Uh, but it's the same thing

409
00:17:05.830 --> 00:17:08.350
basically, uh, different, different levels of

410
00:17:08.350 --> 00:17:11.030
energy. So you get these gamma rays which

411
00:17:11.030 --> 00:17:13.310
will be emitted with a specific and

412
00:17:13.310 --> 00:17:16.030
characteristic frequency and that's the way

413
00:17:16.270 --> 00:17:18.910
that you might be able to detect

414
00:17:19.710 --> 00:17:21.150
an antimatter star.

415
00:17:22.070 --> 00:17:22.100
Andrew Dunkley: Um.

416
00:17:24.110 --> 00:17:26.310
Professor Fred Watson: I think this story actually goes back, it

417
00:17:26.310 --> 00:17:28.550
does go back to 2021. I've just found the

418
00:17:28.550 --> 00:17:30.950
article that we referred to. Stars made of

419
00:17:30.950 --> 00:17:32.710
antimatter might be lurking in the universe.

420
00:17:32.710 --> 00:17:34.430
It's from Scientific American, a very

421
00:17:34.590 --> 00:17:37.050
authoritative source. Um,

422
00:17:37.550 --> 00:17:40.270
but what they were starting the story

423
00:17:40.270 --> 00:17:42.910
with was something that happened in 2018

424
00:17:43.590 --> 00:17:46.230
when uh, one of the

425
00:17:46.230 --> 00:17:47.630
experiments on the outside of the

426
00:17:47.630 --> 00:17:49.190
International Space Station which we talked

427
00:17:49.190 --> 00:17:51.630
about in the last episode with great warmth

428
00:17:51.630 --> 00:17:54.250
and admiration. Um,

429
00:17:54.390 --> 00:17:56.790
it's one of those experiments may have

430
00:17:56.790 --> 00:17:58.950
detected uh, two

431
00:18:00.310 --> 00:18:02.880
basically uh, nuclei of anti helium. Um,

432
00:18:03.590 --> 00:18:05.830
these are anti helium particles.

433
00:18:06.390 --> 00:18:09.230
And so you mix that with normal helium

434
00:18:09.230 --> 00:18:10.950
and you get the gamma rays.

435
00:18:11.420 --> 00:18:14.230
Um, and so the question

436
00:18:14.310 --> 00:18:17.310
is where, where does

437
00:18:17.310 --> 00:18:20.030
that come from? And that was

438
00:18:20.030 --> 00:18:22.950
the um, the outcome of this, the, the

439
00:18:22.950 --> 00:18:25.830
suggestion that the easiest way to produce

440
00:18:25.830 --> 00:18:28.550
anti helium is inside anti stars.

441
00:18:29.240 --> 00:18:32.070
Um, which we don't, still

442
00:18:32.070 --> 00:18:34.670
don't know whether they exist or not. Uh, but

443
00:18:34.670 --> 00:18:37.430
really the, the point of Marx question is a

444
00:18:37.430 --> 00:18:39.980
good one. Um, I don't think we know much more

445
00:18:39.980 --> 00:18:41.640
about this uh,

446
00:18:42.700 --> 00:18:45.180
since that you know that speculation.

447
00:18:46.000 --> 00:18:48.300
Um, but what they're

448
00:18:48.460 --> 00:18:51.420
suggesting, uh, I might actually read

449
00:18:51.880 --> 00:18:54.460
uh, from that Scientific American article

450
00:18:54.699 --> 00:18:56.860
and acknowledge the source there.

451
00:18:57.500 --> 00:18:58.620
It was written by

452
00:18:59.980 --> 00:19:02.940
Leto Supuna who's the author

453
00:19:02.940 --> 00:19:05.820
of that. Um, and I think it

454
00:19:06.060 --> 00:19:08.860
sort of puts it a lot better than I can.

455
00:19:09.100 --> 00:19:12.060
Antistars would shine much as normal ones do,

456
00:19:12.060 --> 00:19:14.540
producing light of the same wavelengths, but

457
00:19:14.540 --> 00:19:16.860
they would exist in a matter dominated

458
00:19:16.860 --> 00:19:19.500
universe. And so as particles and

459
00:19:19.500 --> 00:19:22.380
gases made of regular matter fell into

460
00:19:22.380 --> 00:19:24.860
an antistar's gravitational pull and made

461
00:19:24.860 --> 00:19:27.180
contact with its antimatter, the resulting

462
00:19:27.180 --> 00:19:29.300
annihilations would produce a flash of high

463
00:19:29.300 --> 00:19:30.900
energy light. That's the gamma rays I

464
00:19:30.900 --> 00:19:33.790
mentioned. We can see this light as a, There

465
00:19:33.790 --> 00:19:35.670
you go. We can see this light as a specific

466
00:19:35.670 --> 00:19:38.630
colour of gamma rays. Um, and

467
00:19:38.630 --> 00:19:40.270
so one of the teams that they're Talking

468
00:19:40.270 --> 00:19:42.840
about took 10 years of data, uh,

469
00:19:43.190 --> 00:19:45.750
which amounted to roughly 6,000 light

470
00:19:45.750 --> 00:19:47.510
emitting objects. They paired the list down

471
00:19:47.510 --> 00:19:49.670
to sources that shone with the right gamma

472
00:19:49.670 --> 00:19:51.710
ray frequency and that were not ascribed to

473
00:19:51.710 --> 00:19:53.910
previously catalogued astronomical objects.

474
00:19:54.510 --> 00:19:57.350
Um, so this left us with

475
00:19:57.350 --> 00:20:00.230
14 candidates. This is one of the authors,

476
00:20:00.350 --> 00:20:02.510
uh, talking, which in my opinion and my co

477
00:20:02.510 --> 00:20:04.770
author's opinion, two are, uh, not antistars.

478
00:20:05.550 --> 00:20:08.410
Um, yeah, but they say

479
00:20:08.410 --> 00:20:11.170
if all those sources were such stars, that

480
00:20:11.170 --> 00:20:13.090
means one anti star would exist for every

481
00:20:13.090 --> 00:20:15.530
400,000 ordinary ones in our stellar neck of

482
00:20:15.530 --> 00:20:18.490
the woods. So we're still

483
00:20:18.490 --> 00:20:20.610
struggling to get our heads around this and

484
00:20:20.610 --> 00:20:23.330
I'm not sure whether any more of uh,

485
00:20:23.330 --> 00:20:26.290
these characteristic gamma ray flashes,

486
00:20:27.050 --> 00:20:29.970
uh, have been observed or what the latest

487
00:20:30.050 --> 00:20:32.410
is on this topic. But it is a very

488
00:20:32.410 --> 00:20:34.260
interesting one, I think. Um, thank you,

489
00:20:34.410 --> 00:20:35.970
Mark, for raising it again because it's one

490
00:20:35.970 --> 00:20:37.450
we should perhaps look at in a bit more

491
00:20:37.450 --> 00:20:40.010
detail. Might try and dig out some

492
00:20:40.010 --> 00:20:42.970
stories for when I return to space nuts on

493
00:20:42.970 --> 00:20:45.890
um, antistars and see what we've got

494
00:20:45.890 --> 00:20:46.610
in that. Uh.

495
00:20:47.130 --> 00:20:48.890
Andrew Dunkley: Do you think they could exist for him?

496
00:20:49.290 --> 00:20:51.930
Professor Fred Watson: I do think they could exist, yeah. Um, I mean

497
00:20:52.250 --> 00:20:53.970
it's one of the big puzzles of the universe

498
00:20:53.970 --> 00:20:56.690
as to why there's so much matter and so

499
00:20:56.690 --> 00:20:59.610
little antimatter. When our best theories of

500
00:20:59.610 --> 00:21:01.370
the origin of the universe suggest that

501
00:21:01.560 --> 00:21:04.520
antimatter and matter were created in equal,

502
00:21:04.680 --> 00:21:07.400
you know, in equal proportions. So

503
00:21:07.570 --> 00:21:10.160
uh, it's, it's one of these, it is, it's one

504
00:21:10.160 --> 00:21:12.640
of these issues that um, is, keeps on

505
00:21:12.640 --> 00:21:15.600
bubbling up and uh, you know, challenging

506
00:21:15.600 --> 00:21:16.440
our understanding.

507
00:21:16.680 --> 00:21:19.680
Andrew Dunkley: Yeah, uh, well, I'm probably dredging up

508
00:21:19.680 --> 00:21:21.280
the same joke I used four and a half years

509
00:21:21.280 --> 00:21:23.160
ago, but there's a lot of, there's a lot of

510
00:21:23.240 --> 00:21:25.720
doesn't matter in astronomy as well.

511
00:21:27.890 --> 00:21:30.610
Professor Fred Watson: See, I can hear Jordy. You got a lot of Jordy

512
00:21:30.610 --> 00:21:31.170
there. Yeah.

513
00:21:32.970 --> 00:21:35.970
Andrew Dunkley: Um, but yeah, antimatter stars are

514
00:21:35.970 --> 00:21:38.450
right up there with white holes. Uh, we've

515
00:21:38.450 --> 00:21:41.010
never seen one. But there's, you know,

516
00:21:41.010 --> 00:21:43.930
there's certain elements of

517
00:21:43.930 --> 00:21:45.890
science that think these things exist.

518
00:21:46.610 --> 00:21:49.330
Um, but we've just never found the,

519
00:21:50.050 --> 00:21:52.050
the direct evidence or proof, have we?

520
00:21:52.530 --> 00:21:54.690
Professor Fred Watson: No, that's. Excuse me. That's correct.

521
00:21:54.910 --> 00:21:57.460
Um, just along those lines, there's

522
00:21:58.100 --> 00:22:00.940
something, um, that cropped, um, up about a

523
00:22:00.940 --> 00:22:03.340
week ago or two weeks ago. Um, it's a

524
00:22:03.340 --> 00:22:06.100
gravitational wave event which I think

525
00:22:06.100 --> 00:22:08.820
dates back to 2019. And you know,

526
00:22:08.900 --> 00:22:11.840
gravitational waves measured by LIGO and uh,

527
00:22:12.180 --> 00:22:14.980
Kagra and Virgo, the three big gravitational

528
00:22:14.980 --> 00:22:17.970
wave detectors in the world. They um,

529
00:22:18.970 --> 00:22:21.500
uh, this particular, most Most gravitational

530
00:22:21.500 --> 00:22:23.180
waves come from, uh, either neutron stars

531
00:22:23.180 --> 00:22:24.860
colliding or neutron stars colliding with

532
00:22:24.860 --> 00:22:27.100
black holes or black holes colliding. And

533
00:22:27.100 --> 00:22:28.880
they always have characteristic signature.

534
00:22:28.880 --> 00:22:31.200
They spiral together and then when they come

535
00:22:31.200 --> 00:22:32.720
together at the end they produce this

536
00:22:32.720 --> 00:22:35.280
characteristic chirp, um,

537
00:22:35.840 --> 00:22:37.570
which is when they merge. Um,

538
00:22:38.960 --> 00:22:41.280
and, uh, that usually lasts a few seconds

539
00:22:41.520 --> 00:22:44.440
that, um, run up to the chirp. Uh, but

540
00:22:44.440 --> 00:22:47.400
this one in 2019 only lasted, I think

541
00:22:47.400 --> 00:22:50.160
it was a tenth of a second. Uh, and

542
00:22:51.920 --> 00:22:54.780
one interpretation of that is that,

543
00:22:55.260 --> 00:22:58.060
uh, it was two very massive

544
00:22:58.060 --> 00:22:59.540
black holes. I think. I think that's the way

545
00:22:59.540 --> 00:23:01.220
around. It goes. Could be the other way

546
00:23:01.220 --> 00:23:04.060
around. Anyway, a,

547
00:23:04.220 --> 00:23:06.460
um, recent paper from China, and I think this

548
00:23:06.460 --> 00:23:09.300
was two weeks ago, proposed that you could

549
00:23:09.300 --> 00:23:12.100
get nearly the same modelling, which,

550
00:23:12.100 --> 00:23:14.260
because they model these gravitational wave

551
00:23:14.260 --> 00:23:17.260
phenomena if, uh, it turned out

552
00:23:17.260 --> 00:23:18.740
that what you were looking at was not

553
00:23:18.740 --> 00:23:21.260
colliding black holes but a collapsing

554
00:23:21.260 --> 00:23:24.100
wormhole. Um, and that's

555
00:23:24.100 --> 00:23:26.300
the first evidence that I think anybody has

556
00:23:26.300 --> 00:23:28.940
put forward for the existence of wormholes.

557
00:23:28.940 --> 00:23:31.820
But it's still very conjectural because,

558
00:23:32.340 --> 00:23:34.900
um, the likelihood, you know, the model of

559
00:23:34.900 --> 00:23:36.980
just two black holes colliding actually fits

560
00:23:36.980 --> 00:23:39.420
the data slightly better than the model of

561
00:23:39.420 --> 00:23:41.740
the collapsing wormhole. But people are still

562
00:23:41.740 --> 00:23:43.420
looking at these things as they are for white

563
00:23:43.420 --> 00:23:45.860
holes and, um, I hope also for

564
00:23:45.860 --> 00:23:46.940
antimotor stars.

565
00:23:47.490 --> 00:23:50.490
Andrew Dunkley: Yes. Yeah. Well, um, I suppose

566
00:23:50.490 --> 00:23:53.210
there's so much to consider in the

567
00:23:53.210 --> 00:23:56.050
universe that some things just don't get the

568
00:23:56.050 --> 00:23:58.170
amount of time and attention they probably

569
00:23:58.170 --> 00:24:01.170
deserve. But the workforce

570
00:24:01.170 --> 00:24:03.369
is spread so thin in astronomy and space

571
00:24:03.369 --> 00:24:05.330
science, I would imagine so,

572
00:24:06.220 --> 00:24:08.930
um. Yeah, it's hard to deal with everything.

573
00:24:09.170 --> 00:24:11.010
Professor Fred Watson: With everything. That's right. There's

574
00:24:11.010 --> 00:24:13.130
certainly enough questions to keep us busy

575
00:24:13.130 --> 00:24:15.210
for a long time. The world of astronomy.

576
00:24:15.370 --> 00:24:16.170
Absolutely.

577
00:24:16.170 --> 00:24:19.050
Andrew Dunkley: Yeah. All right, Mark, thank you. Hope

578
00:24:19.050 --> 00:24:20.490
all is well in Canada.

579
00:24:23.290 --> 00:24:24.690
Roger, you're live right here.

580
00:24:24.690 --> 00:24:26.170
Professor Fred Watson: Also, space nuts.

581
00:24:26.490 --> 00:24:29.460
Andrew Dunkley: Our final question comes from Dave. And, uh,

582
00:24:29.460 --> 00:24:32.450
Dave is from Inverel in Northern, uh, New

583
00:24:32.450 --> 00:24:34.970
South Wales, Australia. As someone who is

584
00:24:34.970 --> 00:24:37.010
lucky enough to enjoy fairly low light

585
00:24:37.010 --> 00:24:39.690
pollution where I live, I like to

586
00:24:39.770 --> 00:24:42.290
attempt some nighttime photography now and

587
00:24:42.290 --> 00:24:45.000
then. Lately I've been using the nightcap

588
00:24:45.000 --> 00:24:47.440
app on my phone. I've got that one as well.

589
00:24:47.920 --> 00:24:50.640
Uh, with, uh, the meteor setting, he says

590
00:24:50.640 --> 00:24:53.120
to try and capture some meteor photos.

591
00:24:53.680 --> 00:24:55.520
Uh, I find the best time to see a great

592
00:24:55.520 --> 00:24:58.200
falling star is just as I'm getting the phone

593
00:24:58.200 --> 00:25:00.160
set up, ready to start shooting.

594
00:25:01.680 --> 00:25:04.000
Just wondering if you have any advice for

595
00:25:04.000 --> 00:25:06.640
when to try and capture a meteor on camera.

596
00:25:07.760 --> 00:25:09.840
Example, uh, time of night, direction, et

597
00:25:09.840 --> 00:25:12.480
cetera. Or should I just uh, wait until a

598
00:25:12.480 --> 00:25:15.340
good meteor shower turns up. Uh, and how many

599
00:25:15.340 --> 00:25:18.340
meteors would we expect to see collide in

600
00:25:18.340 --> 00:25:20.860
our atmos, uh, collide with our atmosphere on

601
00:25:20.860 --> 00:25:23.700
any given night. Um, also,

602
00:25:23.900 --> 00:25:25.580
uh, great to hear you back Andrew and

603
00:25:25.580 --> 00:25:28.440
hearing. Enjoy, uh, hearing your travels. Uh,

604
00:25:28.440 --> 00:25:31.380
when you talk of Iceland, it makes me very

605
00:25:31.380 --> 00:25:32.100
keen to return.

606
00:25:32.180 --> 00:25:34.820
Can I ask which company you cruised with?

607
00:25:34.820 --> 00:25:37.060
Dave from Inverel. Yes, you can.

608
00:25:38.720 --> 00:25:41.650
Uh, the uh, the answer, uh, is Princess.

609
00:25:41.650 --> 00:25:44.650
It was Princess Cruises. Uh, we made the

610
00:25:44.650 --> 00:25:47.490
news early in the cruise when we got smashed

611
00:25:47.490 --> 00:25:50.210
just um, southwest corner of Australia by

612
00:25:50.290 --> 00:25:52.330
a squall that knocked the ship over, not

613
00:25:52.330 --> 00:25:55.290
completely 7 degree list which

614
00:25:55.290 --> 00:25:57.690
we took three hours to straighten up. I had

615
00:25:57.690 --> 00:25:59.330
to go up to the bridge and help the captain

616
00:25:59.570 --> 00:26:02.250
by, you know, using my weight to stand at

617
00:26:02.250 --> 00:26:04.740
the. No, I didn't. Uh, but uh, it was um,

618
00:26:05.330 --> 00:26:07.570
pretty hair, uh, raising for a while there.

619
00:26:07.730 --> 00:26:09.170
We uh, made the news all over Australia

620
00:26:09.250 --> 00:26:11.370
apparently. But um, yeah, it was the Princess

621
00:26:11.370 --> 00:26:14.150
Cruise Line. Um, and we've been with them

622
00:26:14.150 --> 00:26:16.450
many times on other cruises and they're uh.

623
00:26:16.510 --> 00:26:19.110
I, I really enjoy them. Um, they

624
00:26:19.110 --> 00:26:21.910
probably uh, it's debatable but I

625
00:26:21.910 --> 00:26:24.030
think food wise they're probably the best.

626
00:26:24.510 --> 00:26:27.350
But yes, um, now, and you

627
00:26:27.350 --> 00:26:29.510
mentioned the. Sorry, go on. Br.

628
00:26:29.510 --> 00:26:31.230
Professor Fred Watson: I was just going to say if you want to avoid

629
00:26:31.340 --> 00:26:33.590
uh, the rigours of sea travel, you could come

630
00:26:33.590 --> 00:26:36.030
with Dark Sky Traveller. We go up to Iceland

631
00:26:36.030 --> 00:26:37.910
pretty regularly too. Yes, well, there's a

632
00:26:37.910 --> 00:26:38.190
thought.

633
00:26:38.480 --> 00:26:38.800
Andrew Dunkley: Yeah.

634
00:26:39.040 --> 00:26:39.520
Professor Fred Watson: Yeah.

635
00:26:39.520 --> 00:26:42.240
Andrew Dunkley: So the downside of cruising is it's slow.

636
00:26:42.560 --> 00:26:44.600
Yeah, I mean it's very relaxing. But if you

637
00:26:44.600 --> 00:26:47.040
do want to get somewhere in a hurry, it's

638
00:26:47.200 --> 00:26:49.470
probably not the way to do it. Um,

639
00:26:50.480 --> 00:26:53.440
and uh, Dave also mentioned the nightcap app.

640
00:26:53.620 --> 00:26:55.920
Uh, I do have that one on my phone. I haven't

641
00:26:55.920 --> 00:26:58.080
had an opportunity to really use it because

642
00:26:58.640 --> 00:27:01.480
it's um, there's too much light around

643
00:27:01.480 --> 00:27:01.840
here.

644
00:27:02.600 --> 00:27:04.600
Professor Fred Watson: Uh, what does it do, Andrew? What's the,

645
00:27:04.600 --> 00:27:06.450
what's the purpose of the nightcap?

646
00:27:06.770 --> 00:27:09.130
Andrew Dunkley: I haven't got my phone with me but uh, you

647
00:27:09.130 --> 00:27:10.530
can preset it to

648
00:27:11.570 --> 00:27:13.090
photograph in low light

649
00:27:14.690 --> 00:27:17.530
and, and you can either put it in manual

650
00:27:17.530 --> 00:27:19.890
mode or you can have this series of presets

651
00:27:19.890 --> 00:27:22.210
where you can, if you know what you want to

652
00:27:22.210 --> 00:27:24.610
photograph, it will set up the phone

653
00:27:25.250 --> 00:27:27.770
to create the exact situation you need to

654
00:27:27.770 --> 00:27:29.850
take that particular photograph. Yeah, yeah,

655
00:27:29.850 --> 00:27:32.210
it's really, it's really good software. Um,

656
00:27:32.470 --> 00:27:35.390
but I haven't really had a chance to use

657
00:27:35.390 --> 00:27:38.070
it properly. But it can do time lapse and all

658
00:27:38.070 --> 00:27:40.710
sorts of things. It's really good gear.

659
00:27:41.480 --> 00:27:44.390
Uh, so yeah, when and where

660
00:27:44.390 --> 00:27:47.270
and how to take low light

661
00:27:47.750 --> 00:27:49.750
photographs, Fred Watson, of meteors.

662
00:27:49.990 --> 00:27:52.630
Professor Fred Watson: That was meteors crucial thing. Yeah. From

663
00:27:52.950 --> 00:27:55.830
Dave's question. And yeah, so Dave up

664
00:27:55.830 --> 00:27:58.610
in Verrel will have pretty easy

665
00:27:58.610 --> 00:27:59.850
access to dark skies.

666
00:28:00.100 --> 00:28:01.850
Andrew Dunkley: Uh, yeah, that's, you know why? You know why?

667
00:28:01.850 --> 00:28:04.130
Because they're not putting the electricity

668
00:28:04.130 --> 00:28:06.090
on up there for another 10 years.

669
00:28:06.970 --> 00:28:08.090
Professor Fred Watson: Okay. Uh, sorry.

670
00:28:08.410 --> 00:28:11.050
Andrew Dunkley: Everyone asks, in the 30

671
00:28:11.130 --> 00:28:12.850
odd years I've lived here people have often

672
00:28:12.850 --> 00:28:14.570
asked do you have electricity where you are?

673
00:28:15.100 --> 00:28:17.450
Um, so I couldn't help that joke.

674
00:28:17.530 --> 00:28:20.330
Professor Fred Watson: No. Well you do. We did in Kun Durban as well

675
00:28:20.330 --> 00:28:22.650
but we were at the end of the line and uh, so

676
00:28:22.650 --> 00:28:24.490
if ever there was a thunderstorm we usually

677
00:28:24.490 --> 00:28:26.090
left our electricity, they were gone.

678
00:28:26.270 --> 00:28:28.550
Andrew Dunkley: Ah yeah, we had that problem the first 15

679
00:28:28.550 --> 00:28:29.550
years we lived here.

680
00:28:31.390 --> 00:28:33.590
Professor Fred Watson: Um, but they do have electricity in Varel and

681
00:28:33.590 --> 00:28:35.910
they also have dark skies. Relatively easily

682
00:28:35.910 --> 00:28:38.830
accessible by just driving up a few

683
00:28:38.910 --> 00:28:41.030
few kilometres further up the highway one way

684
00:28:41.030 --> 00:28:41.550
or the other.

685
00:28:42.130 --> 00:28:44.820
Um, so, so meteors. Um,

686
00:28:45.070 --> 00:28:46.950
yeah. Dave's question, how many meteors are

687
00:28:46.950 --> 00:28:49.870
coming in? Uh, quite a large number. We think

688
00:28:49.870 --> 00:28:52.750
it's something like 100 tonnes, 50 to 100

689
00:28:52.750 --> 00:28:55.670
tonnes a day meteoritic material hits the

690
00:28:55.670 --> 00:28:58.270
atmosphere that's worldwide. Uh, but that

691
00:28:58.270 --> 00:29:00.430
means there are billions of meteors streaking

692
00:29:00.430 --> 00:29:01.790
through the atmosphere because most of them

693
00:29:01.790 --> 00:29:04.670
are specks of dust. Um, and they

694
00:29:04.670 --> 00:29:07.070
can, yeah, sporadic meteors as they're

695
00:29:07.070 --> 00:29:08.870
called, they can whiz through the earth's

696
00:29:08.870 --> 00:29:11.110
atmosphere at any time. People talking about

697
00:29:11.190 --> 00:29:13.950
this stargazing I was doing at uh, Sea

698
00:29:13.950 --> 00:29:16.810
Lake uh in rural Victoria last week, um,

699
00:29:17.190 --> 00:29:19.470
quite a few people were spotting meteors as

700
00:29:19.470 --> 00:29:21.110
they flashed through the sky. I was looking

701
00:29:21.110 --> 00:29:23.790
at screens so I missed a, most of them. Um,

702
00:29:24.180 --> 00:29:27.060
but uh, probably the

703
00:29:27.140 --> 00:29:29.540
time to uh,

704
00:29:30.740 --> 00:29:33.580
really concentrate on uh, if you serious and

705
00:29:33.580 --> 00:29:35.580
I think you kind of need an all sky lens

706
00:29:35.580 --> 00:29:38.460
effectively for good meteor photography. Um,

707
00:29:39.110 --> 00:29:42.100
um, uh, the new generation of

708
00:29:42.660 --> 00:29:45.620
phones do have very wide angle lenses

709
00:29:46.180 --> 00:29:48.220
but they're not fisheye in the sense that you

710
00:29:48.220 --> 00:29:50.860
can see the whole sky. Uh, but they're wide

711
00:29:50.860 --> 00:29:53.580
enough probably to use the

712
00:29:53.580 --> 00:29:55.980
snag with them is that they've got a low

713
00:29:56.710 --> 00:29:59.340
uh, uh aperture. So a

714
00:29:59.660 --> 00:30:02.460
high focal ratio, uh, you know

715
00:30:02.540 --> 00:30:05.460
the ratio of the focal length to aperture and

716
00:30:05.460 --> 00:30:07.539
what you need is a low focal ratio to give

717
00:30:07.539 --> 00:30:09.620
you fast imaging, it's what we call a fast

718
00:30:09.620 --> 00:30:12.020
lens. Whereas these wide angle ones tend not

719
00:30:12.020 --> 00:30:15.020
to have that. Uh, and so you're tossing up

720
00:30:15.020 --> 00:30:17.820
you know, the relative merits of a very

721
00:30:17.820 --> 00:30:19.660
wide angle view or

722
00:30:20.820 --> 00:30:23.220
likely to capture more meteors or a narrow

723
00:30:23.220 --> 00:30:25.300
angle of view. But greater sensitivity, so

724
00:30:25.300 --> 00:30:27.450
you'll see fainter meteors. So, um,

725
00:30:28.020 --> 00:30:29.780
that's, you know, taking all that into

726
00:30:29.780 --> 00:30:32.260
consideration. I, um, haven't tried meteor

727
00:30:32.260 --> 00:30:33.980
photography with my phone. I've done a lot of

728
00:30:33.980 --> 00:30:36.219
aurora borealis photography with it and that

729
00:30:36.219 --> 00:30:38.260
works really well because they're sensitive.

730
00:30:38.420 --> 00:30:40.500
But it will be an interesting thing to try.

731
00:30:40.890 --> 00:30:43.500
Uh, it's the fact that you need the shutter

732
00:30:43.500 --> 00:30:45.020
open for a long time. But I guess what you

733
00:30:45.020 --> 00:30:47.890
can do is just keep on taking short

734
00:30:47.890 --> 00:30:50.890
snapshots. Um, the point I was going to

735
00:30:50.890 --> 00:30:53.720
get to is when you think about the Earth, uh,

736
00:30:54.010 --> 00:30:56.010
in its orbit around the sun,

737
00:30:56.730 --> 00:30:59.490
uh, the forward facing side of the orbit

738
00:30:59.490 --> 00:31:01.450
is where you are after midnight.

739
00:31:02.250 --> 00:31:05.130
So after midnight means that you're

740
00:31:05.130 --> 00:31:07.970
on the leading edge of the Earth and that's

741
00:31:07.970 --> 00:31:09.770
where you're going to get the most meteors.

742
00:31:09.850 --> 00:31:12.690
Basically, uh, as the Earth, uh, ploughs

743
00:31:12.690 --> 00:31:14.700
through the various clouds of dust, you've

744
00:31:14.700 --> 00:31:17.260
got meteor showers which come from big clouds

745
00:31:17.260 --> 00:31:19.820
of dust that the Earth goes through. But

746
00:31:19.820 --> 00:31:22.420
these things are always best seen in the

747
00:31:22.420 --> 00:31:24.820
early morning, um, when you're on the side

748
00:31:24.820 --> 00:31:27.340
after midnight. So that's the best advice I

749
00:31:27.340 --> 00:31:28.860
can give. I'd be interested to hear how you

750
00:31:28.860 --> 00:31:31.220
get on Dave and, uh, what sort of results you

751
00:31:31.220 --> 00:31:31.740
might get.

752
00:31:31.900 --> 00:31:34.060
Andrew Dunkley: Yeah, yeah. And if you do get a couple of

753
00:31:34.060 --> 00:31:35.780
good ones, send them in and we'll, we'll, um,

754
00:31:36.100 --> 00:31:38.260
post them on our Facebook page or you can

755
00:31:38.260 --> 00:31:39.860
post them yourself on the Facebook group,

756
00:31:39.860 --> 00:31:41.940
whatever you like. Um, love to see what you

757
00:31:41.940 --> 00:31:44.300
come up with. We do get, um, some great

758
00:31:44.620 --> 00:31:46.770
astronauts of photography from space, uh,

759
00:31:47.000 --> 00:31:48.720
arts listeners on the Facebook group

760
00:31:48.720 --> 00:31:51.320
sometimes. So, yeah, um, more than happy to,

761
00:31:52.170 --> 00:31:54.920
uh, have you, uh, post them

762
00:31:55.160 --> 00:31:57.920
on that page, Dave, and

763
00:31:57.920 --> 00:31:59.930
hopefully that will help. But, uh, yeah, uh,

764
00:31:59.930 --> 00:32:01.640
the idea of having to get up and do it at the

765
00:32:01.640 --> 00:32:03.550
middle of night, not, not appealing. But, uh,

766
00:32:03.800 --> 00:32:05.400
that's life in astronomy, isn't it,

767
00:32:05.400 --> 00:32:05.800
Fred Watson?

768
00:32:06.040 --> 00:32:07.080
Professor Fred Watson: Tis a bit, yeah.

769
00:32:08.280 --> 00:32:11.000
Andrew Dunkley: Yeah. All right, Dave, thanks very much for

770
00:32:11.000 --> 00:32:12.400
your question. Don't forget, if you've got a

771
00:32:12.400 --> 00:32:14.960
question, send it in to us because we'd love

772
00:32:14.960 --> 00:32:17.720
to try, uh, and answer it. No guarantees, of

773
00:32:17.720 --> 00:32:19.960
course, uh, but you go to our website,

774
00:32:19.960 --> 00:32:22.880
spacenutspodcast.com spacenuts

775
00:32:22.880 --> 00:32:25.770
IO Click on the AMA tab and you can send, uh,

776
00:32:26.150 --> 00:32:28.760
uh, questions there, audio or text. Just

777
00:32:28.760 --> 00:32:30.520
remember to tell us who you are and where

778
00:32:30.520 --> 00:32:33.360
you're from and we'll do the rest. Or

779
00:32:33.360 --> 00:32:36.120
Huw in the studio will, if he ever turns up

780
00:32:36.120 --> 00:32:38.720
again. He didn't turn up today.

781
00:32:39.360 --> 00:32:41.760
I don't know what he was doing. Probably

782
00:32:41.760 --> 00:32:43.880
trying astrophotography in the middle of the

783
00:32:43.880 --> 00:32:46.510
day. Just never listens to us.

784
00:32:46.750 --> 00:32:49.150
That's his problem. Uh, Fred Watson, thank

785
00:32:49.150 --> 00:32:52.110
you as always and, uh, bon voyage.

786
00:32:52.110 --> 00:32:54.990
Have a safe journey. Uh, enjoy your time in,

787
00:32:54.990 --> 00:32:57.950
in Japan and Ireland and the, uh, UK

788
00:32:58.190 --> 00:33:00.670
and uh. Yeah, and, and look forward to

789
00:33:00.670 --> 00:33:02.350
hearing about your travels when you get back.

790
00:33:02.830 --> 00:33:05.830
And we will welcome, uh, Jonty Horner from

791
00:33:05.830 --> 00:33:08.320
the University of Southern Queensland, uh,

792
00:33:08.510 --> 00:33:11.360
with, um, Space Nuts for the

793
00:33:11.360 --> 00:33:13.320
foreseeable future. So take care,

794
00:33:13.320 --> 00:33:14.600
Fred Watson, and thank you.

795
00:33:15.240 --> 00:33:17.240
Professor Fred Watson: Thank you, Andrew. Uh, I'll miss you all,

796
00:33:17.240 --> 00:33:19.750
but, um, I'll be glad to come back and, uh,

797
00:33:19.750 --> 00:33:21.720
talk to you sometime before Christmas.

798
00:33:21.880 --> 00:33:23.950
Andrew Dunkley: Okay, catch you then, professor, uh,

799
00:33:23.950 --> 00:33:25.680
Fred Watson Watson, astronomer at large, and

800
00:33:25.680 --> 00:33:27.400
from me, Andrew Dunkley. Thanks again for

801
00:33:27.400 --> 00:33:29.240
your company. We'll see you on the very next

802
00:33:29.240 --> 00:33:31.960
episode of Space Nuts. Until then, bye

803
00:33:31.960 --> 00:33:32.280
bye.

804
00:33:33.400 --> 00:33:35.600
Voice Over Guy: You've been listening to the Space Nuts

805
00:33:35.600 --> 00:33:38.220
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808
00:33:43.540 --> 00:33:45.220
player. You can also stream on

809
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810
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811
00:33:50.300 --> 00:33:51.340
bitesz.com