Time Dilation, Black Hole Mysteries & Cosmic Curiosities | Space Nuts: Astronomy Insights &...

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Hello again. Thanks for joining us. This


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is Space Nuts Q&A edition. My name is


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Andrew Dunley. This will be our last


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official show for 2025. We'll go into a


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short recess and be back with you early


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in the new year. Uh but we've got some


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questions to nail down before any of


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that happens. And we've got a whole


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bunch of topics that seem to have


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stirred the imaginations of uh our


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audience. Uh Andrew wants to know about


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time dilation of stars.


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Uh Adriano is talking black holes


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becoming stars. Uh Ishtto uh is wanting


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to ask about free space.


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H


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I always thought it was expensive


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officially all the space around where we


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live. Y and Ggo red shift and graars. We


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will tackle all of that in this edition


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of Space Nuts.


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>> 15 seconds. Guidance is internal. 10 9


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ignition sequence start.


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>> Space nuts.


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>> 5 4 3 2


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>> 1 2 3 4 5 5 4 3 2 1


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>> Space nuts.


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>> Astronauts report. It feels good.


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>> And here he is again. It's Professor


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Fred Watson, an astronomer at large.


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Hello, Fred.


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>> Hello, Andrew.


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>> Good to see you again.


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>> Fancy seeing you.


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>> Yeah. How odd. How strange.


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>> How strange. Hm. Uh getting ready for


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your Christmas break. I mean, you've


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just come back from a break, so you'd


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be, you know, probably


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feeling rather relaxed. Well, no. Uh


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because only the last six days weren't


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work.


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>> Ah.


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>> Yeah.


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So, um No, that's not quite true because


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we did have some time off with my family


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in Scotland. Um but we did have a proper


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holiday at the end of our trip. But yes,


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we did two months of pretty hard work.


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Ku had a tour in Japan and then uh the


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conference in Ireland and a few other


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things like that that um kept us busy.


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So uh


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>> if you if you want to call international


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travel a job that's you know that's


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fine.


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>> Um


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>> want to call it work.


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>> Um if you Yeah. But when you've got a


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tour group when you got 20 people who


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you were entertained for a month or it's


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actually three and a half weeks. Um it


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is work. Yeah. Yeah. Well, we've got a


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similar problem in the coming week or


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two with four grandchildren that we're


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taking to the co.


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>> Yeah. To be honest, I'd rather have 20


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tourists than four grandchildren.


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Although my grandchildren are now


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totally self-propelled, apart from the


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youngest one, Agie. She's on it. She's


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she's nine months like yesterday


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actually.


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>> Anyway,


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>> anyway, yes,


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>> it's a matter of But we Yeah. So, we The


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bottom line is we will have a relaxing


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end of year break, I hope.


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>> Very good.


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Um, you mentioned Edinburgh. Well, uh,


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our first question comes from Andrew in


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Edinburgh. Uh, he says, "I have a


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two-part question about, uh, the gravity


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and subsequent d time dilation that


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occurs in and around super giant stars.


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If the super giants can collapse into


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black holes, then they must have as much


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or even more mass than the resulting


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black hole just spread over a much


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larger area." Uh, I guess my question


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is, is there significant time dilation


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near these stars or are they simply not


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dense enough to have meaningful amounts


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of time dilation? If they do, it's weird


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that it never comes up. And a slight


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followup would be, what about time


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dilation within the star itself?


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Presumably near the core of these stars,


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the density ramps right up. Does a large


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difference in time dilation within a


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star have any impact on how it behaves?


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Hope that all makes sense. Thanks. Love


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the show. That's Andrew in Edinburgh.


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>> They're great questions. Um um


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I'm just not sure about


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the first sentence. If the super giants


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can collapse into black holes, then they


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must have as much or even more mass than


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the resulting black hole. Yeah. Okay.


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I've read that properly now. Uh just


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spread.


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>> Maybe I didn't read it properly.


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>> No, it's all right. No, it's it's fine.


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Um so, so yeah, Andrew's first question


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is there significant time dilation near


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these stars? And the answer is yes. Uh


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the there would be. Um um it's I mean


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the time dilation in a black hole is so


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great that uh to an outside observer,


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time stops on the event horizon. uh for


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a star because it's it's spread over a


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larger volume of space, the time


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dilation is nowhere near as great.


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>> Uh but time dilation will be something


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that you would have to take into account


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if you had um a spacecraft orbiting near


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a giant star. Um the bottom line is with


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and time dilation is is it's a little


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bit spooky in the sense that to to the


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star itself and to something uh you know


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say you've got something in orbit around


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this star their time ticking away at the


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normal rate the time dilation is only


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what you see from the outside.


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>> So this is this is basically the same as


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we were talking about in the last


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episode regarding Mars. Same problem.


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>> Yes that's right it is the same thing.


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Yeah. So, so time ticks away normally


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for the star, but to to watch it from


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the outside, you basically see time


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ticking away a little bit more slowly.


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Um, so so they they would have time


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dilation. Um, and Andrew is asking


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whether they're not simply not dense


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enough to have a meaningful amount of


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time dilation. And um, I don't think


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that's true. I think that this time


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dilation is significant, especially if


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you're looking at microsconds as we were


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in the last episode. Um yeah. Uh so they


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they do and look you're not talking


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about time dilation of the kind that was


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depicted in Interstellar where you know


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time kind of grinds to a halt almost. Uh


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it's a it's a more modest amount of time


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dilation but it would would actually


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happen. And uh Andrew's follow-up


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question. What about time dilation


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within the star itself? Presumably near


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the core this of these stars the density


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ramps right up. Does a large difference


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in time?


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>> I'm not going in there to find out.


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>> Does a large difference in time dilation


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within a star have any impact on how it


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behaves? Um, and there's a curious thing


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there because as you uh get near the the


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core of an object uh with spherical


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symmetry,


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um your gravitational field gets less


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and less. Uh and in fact, at the center,


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you wouldn't feel any gravity. And


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that's because everything's pulling you


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in the same direction all around. And I


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so I believe that time dilation will


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probably stop in the middle of a star.


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That might be right. So something I've


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never thought about before. Uh maybe


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that's not true because you you're still


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in a gravitational field. The fact that


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it cancels out everywhere. I'll check


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that one out actually and try and


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remember for our first show next year


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because that's a really interesting


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question. Time dilation in the center of


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a star. How does it behave?


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>> Yeah.


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>> Very interesting. But there wouldn't be


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a I I think the bottom line is there


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wouldn't be a a big difference in time


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dilation from one part of a star to


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another. That's that's what I'm trying


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to say.


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>> But he brings up another interesting


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point. You've got time dilation around a


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massive star. Yeah. Then it goes, you


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know, whatever black hole. Uh the time


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dilation changes.


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>> Yes, it does. Because um as it


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collapses, the the gravitational field


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increases. uh in increases in in um sort


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of angle in the sense that you know it's


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a steeper gravitational uh field as you


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get as the black hole collapses. And by


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that I'm thinking of the gravitational


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well you know this dip in in the in the


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trampoline sheet that's the


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gravitational well of an object which


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turns into something like a plug hole.


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Yeah. With water going around it as a


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vortex for a black hole. Uh so that's


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what I mean by the steepness of the


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gravitational field. Um and yes, it is


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so steep that the event horizon


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delineates where the time dilation


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becomes uh such that time appears to


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stop on the surface of the event


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horizon.


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>> Yeah, I've I've seen that demonstration


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done with like a a big rubber sheet and


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they say that right that's that's the


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time space-time continuum. Then they put


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a bowling ball in it and they said


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that's gravity.


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>> Yeah, that's right. Yep. Um I know.


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Yeah,


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>> it's a simple way of explaining it, but


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that's that's what it is. Um I suppose.


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>> Um great questions, Andrew, and I hope


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all is well in Edinburgh. Um Fred's uh


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Fred's home stomping ground. Um


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>> yep.


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>> Yeah, I'll give you his address and he


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can go and rock his roof. This is Bas


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Arts with Andrew Dunley and Professor


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Fred Watson. Uh we have got an audio


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question, Fred. This is from Adriano.


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Hi guys, Adrianiano from Florence in


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Italy. I have my first question about


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black holes. So if I understood


00:09:07.760 --> 00:09:09.910
correctly, a star continue to burn his


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fuel like hydrogen and helium and there


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are nuclear fusions and there is enough


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energy for the star to fight against its


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own gravitational pool. But at some


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point there is not enough fuel and the


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star collapse into a black hole. After


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this the black hole will start to absorb


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material like hydrogen and then it


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should have enough energy enough fuel to


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have nuclear fusions and to fight


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against the gravitational pool but uh so


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why a black hole cannot turn back into a


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star? I'm sure this is not possible but


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I cannot understand why. And also guys


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we had a lot of beautiful updates from


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the princess. Can we also have some


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updates from Fred? Thank you guys.


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Bye-bye,


00:09:55.760 --> 00:09:57.829
>> Adrianiano. Thank you very much. Um Fred


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gave us his update when he got back.


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>> But uh yeah, your point is well made. Um


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Florence, what a beautiful beautiful


00:10:06.320 --> 00:10:06.790
city.


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>> Yeah. Isn't it just


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>> uh we we visited Florence a few years


00:10:09.920 --> 00:10:13.910
ago and uh it was it was


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amazing, but it was also terrible timing


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because it was All Saints weekend, which


00:10:17.519 --> 00:10:19.430
is a 4-day long weekend, and there were


00:10:19.440 --> 00:10:22.150
like tens of thousands of people there.


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You couldn't move. You absolutely


00:10:24.720 --> 00:10:28.150
couldn't move. So, um uh we went to what


00:10:28.160 --> 00:10:31.030
was it called? The Ponttovecia. Um and


00:10:31.040 --> 00:10:32.710
we couldn't get near it. You just


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couldn't. It was um it was insane. Yeah.


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We didn't know until we got there.


00:10:37.760 --> 00:10:40.310
That's what was happening. But yeah, we


00:10:40.320 --> 00:10:41.750
still got to see it. It was a beautiful


00:10:41.760 --> 00:10:44.310
place. And all those amazing statues and


00:10:44.320 --> 00:10:47.670
Galileo got got up close with Galileo.


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>> Very good. Yeah.


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>> Yeah. Yeah. Did you see his um I think


00:10:51.600 --> 00:10:53.509
it's his it's one of his fingers or his


00:10:53.519 --> 00:10:54.870
thumb. I can't remember which is on


00:10:54.880 --> 00:10:56.710
display in the science museum there.


00:10:56.720 --> 00:10:59.030
>> Oh, no. No. Couldn't get near that. Um


00:10:59.040 --> 00:11:01.670
honestly, it was just mayhem. But um


00:11:01.680 --> 00:11:04.310
yeah, understandable though. Um all


00:11:04.320 --> 00:11:06.949
right, so the bottom line with Adriano's


00:11:06.959 --> 00:11:10.230
question is um why can't a black hole


00:11:10.240 --> 00:11:13.110
turned back into a star? Um yeah, I


00:11:13.120 --> 00:11:14.630
would I would think there'd be all sorts


00:11:14.640 --> 00:11:16.790
of reasons why not.


00:11:16.800 --> 00:11:18.790
>> Well, that's right. I think once you've


00:11:18.800 --> 00:11:22.150
turned into a singularity uh as the um


00:11:22.160 --> 00:11:26.389
>> you can't double down. Boom. Boom.


00:11:26.399 --> 00:11:27.590
>> Sorry.


00:11:27.600 --> 00:11:30.230
>> That you took the words out of my mouth.


00:11:30.240 --> 00:11:33.509
>> No, you didn't. Um I mean all bets are


00:11:33.519 --> 00:11:35.190
off basically once you once you've gone


00:11:35.200 --> 00:11:39.590
into a singularity. Uh and so um I think


00:11:39.600 --> 00:11:41.990
you know it's it's a great thought that


00:11:42.000 --> 00:11:44.870
um Adriano's had. I and that it's never


00:11:44.880 --> 00:11:47.350
occurred to me before, but but you know,


00:11:47.360 --> 00:11:49.910
you're talking about hydrogen uh which


00:11:49.920 --> 00:11:51.590
certainly would get sucked into a black


00:11:51.600 --> 00:11:54.150
hole because a lot of the gas clouds


00:11:54.160 --> 00:11:57.350
that um that a black hole um accretion


00:11:57.360 --> 00:12:00.310
disc would would draw in and and suck


00:12:00.320 --> 00:12:04.710
into the center. Uh that um uh that


00:12:04.720 --> 00:12:07.509
that's that's hydrogen. Uh and hydrogen


00:12:07.519 --> 00:12:09.910
is the raw material of stars. Why can't


00:12:09.920 --> 00:12:12.230
nuclear fusion kick in again and drive


00:12:12.240 --> 00:12:14.389
the star back into being a star rather


00:12:14.399 --> 00:12:16.069
than a black hole? And I think the


00:12:16.079 --> 00:12:19.990
answer is in structure. Um so stars have


00:12:20.000 --> 00:12:23.350
quite a complex structure uh to make


00:12:23.360 --> 00:12:26.870
them work uh with the the core with all


00:12:26.880 --> 00:12:28.550
the nuclear burning taking place. Then


00:12:28.560 --> 00:12:30.550
there's a convection zone and then


00:12:30.560 --> 00:12:32.470
there's an sort of outer layer before


00:12:32.480 --> 00:12:33.910
you get to the photosphere. the layer


00:12:33.920 --> 00:12:36.710
that you can see um when you've put


00:12:36.720 --> 00:12:39.190
something into a singularity all


00:12:39.200 --> 00:12:44.230
structure disappears and um it almost


00:12:44.240 --> 00:12:48.150
relates to um an issue that occupied the


00:12:48.160 --> 00:12:50.069
mind of Steven Hawking for a while which


00:12:50.079 --> 00:12:53.430
is that does information get lost when


00:12:53.440 --> 00:12:55.750
when it goes into a black hole


00:12:55.760 --> 00:12:58.150
>> and I think there was some argument with


00:12:58.160 --> 00:12:59.990
another well-known physicist in fact I


00:13:00.000 --> 00:13:03.110
think they had a bet uh which Hawin lost


00:13:03.120 --> 00:13:06.870
Um because the um the the b the I think


00:13:06.880 --> 00:13:08.790
the bottom line was hawking bet that


00:13:08.800 --> 00:13:10.470
information couldn't come out of a black


00:13:10.480 --> 00:13:12.710
hole but somebody proved a theory that


00:13:12.720 --> 00:13:14.069
information could come out of a black


00:13:14.079 --> 00:13:15.590
hole. I think I've got the the right way


00:13:15.600 --> 00:13:16.230
round.


00:13:16.240 --> 00:13:16.710
>> Okay.


00:13:16.720 --> 00:13:18.389
>> But basically it's all completely


00:13:18.399 --> 00:13:21.829
mangled in in terms of you know we don't


00:13:21.839 --> 00:13:23.509
understand the physics of what would


00:13:23.519 --> 00:13:25.590
happen inside a singularity. We just


00:13:25.600 --> 00:13:27.670
have no idea what the physical processes


00:13:27.680 --> 00:13:29.910
would be and they almost certainly would


00:13:29.920 --> 00:13:34.069
rule out hydrogen atoms getting together


00:13:34.079 --> 00:13:36.870
uh and with enough temperature to to to


00:13:36.880 --> 00:13:38.870
produce the nuclear fusion that we see


00:13:38.880 --> 00:13:41.350
in a normal star.


00:13:41.360 --> 00:13:43.509
A a black hole is a very abnormal


00:13:43.519 --> 00:13:46.870
object. Nothing relates to normal in a


00:13:46.880 --> 00:13:49.030
black hole. And so I think that is the


00:13:49.040 --> 00:13:51.990
answer to Adriana's question. uh physics


00:13:52.000 --> 00:13:53.990
physics doesn't work the way it works on


00:13:54.000 --> 00:13:55.750
the outside of a black hole and I think


00:13:55.760 --> 00:13:57.509
that's why we don't see black holes


00:13:57.519 --> 00:13:58.790
turning into stars.


00:13:58.800 --> 00:14:01.110
>> Yeah. Well, there's also the fuel issue


00:14:01.120 --> 00:14:03.509
like um you know the the star has


00:14:03.519 --> 00:14:06.710
collapsed because of fuel depletion has


00:14:06.720 --> 00:14:07.430
it not?


00:14:07.440 --> 00:14:08.790
>> Yes, that's right. But what we're saying


00:14:08.800 --> 00:14:10.710
and what Adriano is saying is that um


00:14:10.720 --> 00:14:13.509
among the stuff that is accreted by the


00:14:13.519 --> 00:14:15.910
black hole when it's sitting there


00:14:15.920 --> 00:14:17.590
gobbling stuff up, a lot of that is


00:14:17.600 --> 00:14:20.470
hydrogen which is the fuel. So, they're


00:14:20.480 --> 00:14:22.550
getting more fuel, but they don't any


00:14:22.560 --> 00:14:24.550
longer have the process to make it turn


00:14:24.560 --> 00:14:27.030
into something that will deliver energy.


00:14:27.040 --> 00:14:28.310
>> I think that's the bottom line.


00:14:28.320 --> 00:14:31.990
>> I get it. I get it. Okay. Um, great


00:14:32.000 --> 00:14:35.590
question though because uh


00:14:35.600 --> 00:14:37.350
we we've


00:14:37.360 --> 00:14:39.829
been talking black holes for I don't


00:14:39.839 --> 00:14:41.750
know how long. Probably since the very


00:14:41.760 --> 00:14:44.550
beginning of the time that this podcast


00:14:44.560 --> 00:14:46.790
began. And I don't think we've ever been


00:14:46.800 --> 00:14:47.910
asked that question before.


00:14:47.920 --> 00:14:50.629
>> No, I think that's right. Yeah.


00:14:50.639 --> 00:14:53.350
>> Says a lot for our for our listeners,


00:14:53.360 --> 00:14:55.269
doesn't it? That they can produce


00:14:55.279 --> 00:14:57.269
questions that we've never had before


00:14:57.279 --> 00:14:59.350
after however many episodes. Is it? It's


00:14:59.360 --> 00:15:01.189
getting on for 500 now.


00:15:01.199 --> 00:15:02.790
>> This is 582.


00:15:02.800 --> 00:15:04.310
>> Oh, 582. Okay.


00:15:04.320 --> 00:15:05.750
>> 582. Yeah.


00:15:05.760 --> 00:15:07.829
>> Right. There you go. Getting on for 600.


00:15:07.839 --> 00:15:10.230
>> I know. It's nuts. I mean, it's


00:15:10.240 --> 00:15:11.829
happening faster because of time


00:15:11.839 --> 00:15:14.389
dilation and the fact that we


00:15:14.399 --> 00:15:15.990
decided to do two episodes a week


00:15:16.000 --> 00:15:19.189
instead of one, but


00:15:19.199 --> 00:15:20.870
I think it's nuts by definition, isn't


00:15:20.880 --> 00:15:23.430
it? Um, I've got a feeling


00:15:23.440 --> 00:15:24.230
>> probably.


00:15:24.240 --> 00:15:25.110
>> Yeah.


00:15:25.120 --> 00:15:27.829
>> Uh, anyway, thank you, Adriano, and hope


00:15:27.839 --> 00:15:30.470
all is well in the beautiful Florence.


00:15:30.480 --> 00:15:32.470
This is Space Nuts with Andrew Dunley


00:15:32.480 --> 00:15:36.150
and Professor Fred Watson.


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00:17:12.880 --> 00:17:15.750
>> 3 2 1


00:17:15.760 --> 00:17:17.029
>> Space nuts.


00:17:17.039 --> 00:17:18.870
>> Our next question doesn't come from


00:17:18.880 --> 00:17:21.909
Italy. It comes from Slovenia. Um Russia


00:17:21.919 --> 00:17:22.630
next door.


00:17:22.640 --> 00:17:24.949
>> Yeah. Uh I am listening to your podcast


00:17:24.959 --> 00:17:27.350
while driving to and from work. Great


00:17:27.360 --> 00:17:29.350
show. I hope you managed to keep control


00:17:29.360 --> 00:17:31.110
because you know this gets a bit crazy


00:17:31.120 --> 00:17:33.590
sometimes. Uh I'm curious about wait for


00:17:33.600 --> 00:17:36.630
it Fred black holes. Uh we know that an


00:17:36.640 --> 00:17:38.950
atom is actually a lot of free space


00:17:38.960 --> 00:17:41.350
where electrons fly around. Uh


00:17:41.360 --> 00:17:44.070
eliminating that we probably probably


00:17:44.080 --> 00:17:47.029
get a neutron star uh with high density.


00:17:47.039 --> 00:17:49.029
But what about a black hole? How does


00:17:49.039 --> 00:17:52.070
this work? Where is the free space uh


00:17:52.080 --> 00:17:53.990
that can be squeezed even further to get


00:17:54.000 --> 00:17:56.230
a black hole uh get black hole material


00:17:56.240 --> 00:17:58.710
and density and to calculate the density


00:17:58.720 --> 00:18:00.950
of the black hole? Would it be a correct


00:18:00.960 --> 00:18:03.430
assumption to take the event horizon as


00:18:03.440 --> 00:18:07.190
the boundary and um based on that


00:18:07.200 --> 00:18:09.350
calculate the volume or is it something


00:18:09.360 --> 00:18:12.710
else? Um thank you. Best regards Isht.


00:18:12.720 --> 00:18:14.789
Um another black hole question. Not


00:18:14.799 --> 00:18:17.430
surprising we get a lot of them.


00:18:17.440 --> 00:18:21.830
>> We do. Yeah. So um the it's a it's a


00:18:21.840 --> 00:18:23.830
great question and I you that's


00:18:23.840 --> 00:18:25.510
absolutely right. An atom is a lot of


00:18:25.520 --> 00:18:27.669
free space empty space


00:18:27.679 --> 00:18:29.909
>> uh with cloud of electrons doing their


00:18:29.919 --> 00:18:33.190
quantum thing. Um if you collapse the


00:18:33.200 --> 00:18:35.110
space down so that only the electrons


00:18:35.120 --> 00:18:37.270
are pushing uh the atoms apart, you've


00:18:37.280 --> 00:18:39.510
got a white dwarf star uh which is


00:18:39.520 --> 00:18:42.070
called electron degenerate. Uh and if


00:18:42.080 --> 00:18:43.430
you get rid of the electrons, then you


00:18:43.440 --> 00:18:45.830
get a neutron star. Exactly as Ishtuk


00:18:45.840 --> 00:18:49.830
says uh with um very high density uh


00:18:49.840 --> 00:18:52.310
where only the neutrons keep the thing


00:18:52.320 --> 00:18:54.870
from collapsing into a black hole. But


00:18:54.880 --> 00:18:58.150
with a black hole um well the free space


00:18:58.160 --> 00:19:00.710
is is is basically disappeared down the


00:19:00.720 --> 00:19:05.909
black hole. Um it's uh it's and in terms


00:19:05.919 --> 00:19:09.909
of its density, you have a definition of


00:19:09.919 --> 00:19:12.150
a black hole. Uh, one of the definitions


00:19:12.160 --> 00:19:13.990
is a point in space with infinite


00:19:14.000 --> 00:19:16.390
density. So, the volume the volume is


00:19:16.400 --> 00:19:18.950
zero. See, Jordi Jordi thinks that as


00:19:18.960 --> 00:19:21.430
well. He does. Gosh, I don't know what's


00:19:21.440 --> 00:19:22.390
happening out there, but


00:19:22.400 --> 00:19:23.750
>> yeah,


00:19:23.760 --> 00:19:25.270
>> I love it.


00:19:25.280 --> 00:19:27.029
>> Oh, we had to hear we had to hear him


00:19:27.039 --> 00:19:29.510
from the last show of the year, didn't


00:19:29.520 --> 00:19:29.669
he?


00:19:29.679 --> 00:19:32.870
>> Last show of the year. That's right.


00:19:32.880 --> 00:19:34.549
>> In full flight.


00:19:34.559 --> 00:19:36.870
>> Um, so yes, so it's a point of infinite


00:19:36.880 --> 00:19:39.669
density. So um it's a comment about


00:19:39.679 --> 00:19:41.110
calculating the density of the black


00:19:41.120 --> 00:19:42.630
hole. Would it be a correct assumption


00:19:42.640 --> 00:19:44.390
to take the event horizon as the


00:19:44.400 --> 00:19:47.029
boundary? Uh no it wouldn't. The event


00:19:47.039 --> 00:19:49.029
horizon is just that imaginary point


00:19:49.039 --> 00:19:52.390
where of no return. Uh and the volume is


00:19:52.400 --> 00:19:54.470
zero. Uh the volume of the black hole is


00:19:54.480 --> 00:19:57.270
zero which is how the the density gets


00:19:57.280 --> 00:20:01.190
infinite because um mass over density


00:20:01.200 --> 00:20:03.350
sorry mass over volume is density. The


00:20:03.360 --> 00:20:06.630
mass is a is a parameter. Um, but the


00:20:06.640 --> 00:20:08.390
volume is zero. I have no idea what's


00:20:08.400 --> 00:20:09.990
happening out there. I drew it with


00:20:10.000 --> 00:20:11.590
Jordy, but he obviously likes this


00:20:11.600 --> 00:20:12.390
conversation.


00:20:12.400 --> 00:20:16.230
>> Yes. Yes, he does. He wants in.


00:20:16.240 --> 00:20:17.590
>> Yeah.


00:20:17.600 --> 00:20:21.590
>> Oh dear. Um, yeah. Look, I still don't


00:20:21.600 --> 00:20:23.830
get


00:20:23.840 --> 00:20:26.390
>> receding into the distance.


00:20:26.400 --> 00:20:29.270
>> Yeah. Probably chasing a snake. Um,


00:20:29.280 --> 00:20:30.950
yeah. Uh,


00:20:30.960 --> 00:20:34.310
>> go ahead, Andrew. No, it's it's hard to


00:20:34.320 --> 00:20:36.950
get your head around something like a


00:20:36.960 --> 00:20:38.870
black hole


00:20:38.880 --> 00:20:41.830
having


00:20:41.840 --> 00:20:45.669
no density.


00:20:45.679 --> 00:20:46.390
>> No volume.




00:20:47.039 --> 00:20:49.510
>> It's got no size. It's got zero


00:20:49.520 --> 00:20:50.630
dimensions.


00:20:50.640 --> 00:20:53.590
>> I mean, we we we give them names based


00:20:53.600 --> 00:20:56.230
on size and yet it has no size. Has no


00:20:56.240 --> 00:20:56.390
volume.


00:20:56.400 --> 00:20:58.149
>> Super massive. Yeah. Well, but it's the


00:20:58.159 --> 00:21:00.470
mass. That's the thing. So the mass is


00:21:00.480 --> 00:21:02.230
defined for a black hole. It's one of


00:21:02.240 --> 00:21:03.750
the properties that they have. The


00:21:03.760 --> 00:21:06.070
there's this thing called the the no


00:21:06.080 --> 00:21:09.350
hair theorem uh which I like very much.


00:21:09.360 --> 00:21:10.070
>> Yeah.


00:21:10.080 --> 00:21:11.510
>> And it's about you know


00:21:11.520 --> 00:21:12.630
>> would that wouldn't


00:21:12.640 --> 00:21:15.750
>> Yeah, that's right. Which there's it's


00:21:15.760 --> 00:21:18.230
about the very few parameters that you


00:21:18.240 --> 00:21:20.230
can get from a black hole. I think it's


00:21:20.240 --> 00:21:22.549
mass, charge and spin. I think that's


00:21:22.559 --> 00:21:25.029
all you know about a black hole. Um


00:21:25.039 --> 00:21:27.270
because the volume's zero and that's why


00:21:27.280 --> 00:21:29.270
the density is zero. Density is mass


00:21:29.280 --> 00:21:31.590
over volume. Volume zero. So the density


00:21:31.600 --> 00:21:33.990
goes to infinite infinity but you can


00:21:34.000 --> 00:21:36.070
vary the mass and that's why we talk


00:21:36.080 --> 00:21:37.669
about super massive black holes and


00:21:37.679 --> 00:21:39.350
intermediate mass black holes and things


00:21:39.360 --> 00:21:40.310
of that sort.


00:21:40.320 --> 00:21:43.190
>> Okay. So what was the answer to the


00:21:43.200 --> 00:21:44.710
question?


00:21:44.720 --> 00:21:48.870
>> Uh no. Right. Right. What was the


00:21:48.880 --> 00:21:51.830
question again? Hang on. Uh yeah. Would


00:21:51.840 --> 00:21:53.430
it be yes would it be correct assumption


00:21:53.440 --> 00:21:55.110
to take the event horizon as a boundary


00:21:55.120 --> 00:21:56.710
and and use that to calculate the


00:21:56.720 --> 00:21:58.470
volume? No. The event horizon is an


00:21:58.480 --> 00:22:02.070
imaginary sphere that um is where the


00:22:02.080 --> 00:22:03.990
thing turns black basically because no


00:22:04.000 --> 00:22:05.669
light can escape


00:22:05.679 --> 00:22:07.270
>> precisely.


00:22:07.280 --> 00:22:10.630
Um hope that helped is uh it's a great


00:22:10.640 --> 00:22:11.110
question.


00:22:11.120 --> 00:22:13.909
>> It is terrific question. Uh just a very


00:22:13.919 --> 00:22:16.630
difficult subject cuz we we just don't


00:22:16.640 --> 00:22:19.669
know a hell of a lot about black holes.


00:22:19.679 --> 00:22:23.110
They're just such a mysterious and


00:22:23.120 --> 00:22:26.310
weird object. And um we we're we're


00:22:26.320 --> 00:22:28.310
still trying to gather information about


00:22:28.320 --> 00:22:30.070
them and they just keep throwing up


00:22:30.080 --> 00:22:32.310
these curve balls at us and not letting


00:22:32.320 --> 00:22:34.630
us in. Not that you want to go in, but


00:22:34.640 --> 00:22:36.710
you know what I mean.


00:22:36.720 --> 00:22:37.990
>> Yes, that's right.


00:22:38.000 --> 00:22:39.510
>> Yeah, quite s.


00:22:39.520 --> 00:22:42.310
>> All right, thanks.


00:22:42.320 --> 00:22:44.149
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00:24:08.080 --> 00:24:09.590
And don't forget the code word Space


00:24:09.600 --> 00:24:11.510
Nuts at the checkout.


00:24:11.520 --> 00:24:12.870
>> Space Nuts.


00:24:12.880 --> 00:24:15.110
>> We have one more question to finish


00:24:15.120 --> 00:24:19.029
things off for 2025 and it it's a real


00:24:19.039 --> 00:24:21.350
European flavor for this episode. This


00:24:21.360 --> 00:24:22.870
is Ggo.


00:24:22.880 --> 00:24:25.590
>> Greetings gentlemen. GGO from Slovakia


00:24:25.600 --> 00:24:27.909
here. I have a question about red


00:24:27.919 --> 00:24:30.390
shifting. Does it have a limit? Is there


00:24:30.400 --> 00:24:32.470
a point beyond which light cannot be


00:24:32.480 --> 00:24:34.950
stretched any further? If so, what


00:24:34.960 --> 00:24:36.870
happens if the light continues to travel


00:24:36.880 --> 00:24:39.350
through expanding space? And the second


00:24:39.360 --> 00:24:41.190
question, could you talk a bit about


00:24:41.200 --> 00:24:44.390
gra? Do you think they might be real?


00:24:44.400 --> 00:24:46.630
Uh, thank you for your time and for the


00:24:46.640 --> 00:24:48.789
great show. Bye.


00:24:48.799 --> 00:24:52.149
>> Thanks, Ggo. Uh, yeah, it's we an


00:24:52.159 --> 00:24:55.590
eclectic mix of nationalities this week.


00:24:55.600 --> 00:24:56.710
Yeah, it's terrific.


00:24:56.720 --> 00:24:57.590
>> Yeah, it's great.


00:24:57.600 --> 00:25:00.310
>> Uh, so two questions he's um he's thrown


00:25:00.320 --> 00:25:03.190
into the mix. Um, yeah. Is there a limit


00:25:03.200 --> 00:25:06.390
on red shift? Um,


00:25:06.400 --> 00:25:09.669
yeah, good one. So,


00:25:09.679 --> 00:25:12.950
uh, yeah, it is a good question. I mean,


00:25:12.960 --> 00:25:19.029
so, so red shift as a term we define as


00:25:19.039 --> 00:25:20.630
being due to the expansion of the


00:25:20.640 --> 00:25:23.750
universe. Um, and it's slightly


00:25:23.760 --> 00:25:26.630
different from the Doppler shift. Uh,


00:25:26.640 --> 00:25:28.710
Doppler shift is something we understand


00:25:28.720 --> 00:25:30.390
well. It's the way the light changes


00:25:30.400 --> 00:25:32.710
wavelength from a moving object. But


00:25:32.720 --> 00:25:34.070
with red shift, we're talking about


00:25:34.080 --> 00:25:36.870
space itself rather than rather than


00:25:36.880 --> 00:25:38.470
objects moving through space. We're


00:25:38.480 --> 00:25:40.789
talking about the way space behaves. Uh


00:25:40.799 --> 00:25:43.590
and so it's a a much more fundamental


00:25:43.600 --> 00:25:46.470
thing than the Doppler shift. So in a


00:25:46.480 --> 00:25:49.750
sense, um there's already a limit to red


00:25:49.760 --> 00:25:55.510
shift. Uh but it's one that is exactly


00:25:55.520 --> 00:25:58.789
related to the age of the universe. Um,


00:25:58.799 --> 00:26:02.230
so and for so what I'm thinking of here


00:26:02.240 --> 00:26:05.990
is the the uh cosmic microwave


00:26:06.000 --> 00:26:08.789
background radiation. That's the wall of


00:26:08.799 --> 00:26:11.430
radiation which corresponds to the


00:26:11.440 --> 00:26:15.190
brightness of the big bang fireball


00:26:15.200 --> 00:26:17.669
which we're still seeing because as we


00:26:17.679 --> 00:26:19.750
look further into space, we look back in


00:26:19.760 --> 00:26:22.310
time. So everywhere in space we see this


00:26:22.320 --> 00:26:24.710
wall of radiation which is now in the


00:26:24.720 --> 00:26:26.549
microwave region of the spectrum which


00:26:26.559 --> 00:26:28.230
is why we call it the cosmic microwave


00:26:28.240 --> 00:26:29.430
background radiation.


00:26:29.440 --> 00:26:29.830
>> Yeah.


00:26:29.840 --> 00:26:34.070
>> And so um it's if I remember rightly


00:26:34.080 --> 00:26:38.549
that is basically the visible flash of


00:26:38.559 --> 00:26:42.470
the big bang because it was it was


00:26:42.480 --> 00:26:46.470
basically a a visible light flash. It's


00:26:46.480 --> 00:26:50.470
the visible flash redshifted by I think


00:26:50.480 --> 00:26:54.710
about 1300 times. So everything in the


00:26:54.720 --> 00:26:57.590
universe must have a that we can observe


00:26:57.600 --> 00:27:00.789
must have a red shift less than that. Uh


00:27:00.799 --> 00:27:03.269
I think 1300 is the the number that


00:27:03.279 --> 00:27:05.029
comes into my mind. I've looked at this


00:27:05.039 --> 00:27:07.669
for a long time. Um but it's visible


00:27:07.679 --> 00:27:11.430
light um whose uh which whose waves have


00:27:11.440 --> 00:27:14.630
been stretched by that amount to give us


00:27:14.640 --> 00:27:17.269
microwaves. So stretched about 1300


00:27:17.279 --> 00:27:19.110
times thereabouts.


00:27:19.120 --> 00:27:21.590
Now um


00:27:21.600 --> 00:27:24.950
as the universe expands and time goes on


00:27:24.960 --> 00:27:27.830
that number will increase not by much


00:27:27.840 --> 00:27:31.830
might become 131 or 135 but as time goes


00:27:31.840 --> 00:27:34.070
on that number is increasing. So


00:27:34.080 --> 00:27:37.110
>> in a sense that's a limit to red shift.


00:27:37.120 --> 00:27:39.350
Uh physically though I don't think there


00:27:39.360 --> 00:27:41.750
is a limit. You could, you know, if if


00:27:41.760 --> 00:27:43.110
you expand the universe, if you're


00:27:43.120 --> 00:27:44.870
talking about 40 billion years into the


00:27:44.880 --> 00:27:46.950
future and the universe is expanding


00:27:46.960 --> 00:27:48.789
more, yes, the cosmic microwave


00:27:48.799 --> 00:27:50.390
background is going to be the cosmic


00:27:50.400 --> 00:27:53.750
long wavelength radio background. Uh,


00:27:53.760 --> 00:27:57.029
and so it's uh it's the the wavelength


00:27:57.039 --> 00:27:59.350
will have stretched more. Uh, so there


00:27:59.360 --> 00:28:03.269
isn't a physical limit, but there is a a


00:28:03.279 --> 00:28:06.310
limit in the real universe. uh simply


00:28:06.320 --> 00:28:07.830
because of the age of the universe. The


00:28:07.840 --> 00:28:10.470
universe hasn't hasn't expanded for long


00:28:10.480 --> 00:28:12.470
enough for the red shift to be more than


00:28:12.480 --> 00:28:14.549
about 1300.


00:28:14.559 --> 00:28:17.269
>> Right. Okay. Yeah. Got it.


00:28:17.279 --> 00:28:19.590
>> Good. What was the other thing? Oh,


00:28:19.600 --> 00:28:19.990
gravity stars.


00:28:20.000 --> 00:28:21.669
>> Oh, grav stars. Yeah, we've had we've


00:28:21.679 --> 00:28:24.149
had questions about gravis stars before


00:28:24.159 --> 00:28:26.549
more than once. Um it it seems to be


00:28:26.559 --> 00:28:28.070
something that sort of captured the


00:28:28.080 --> 00:28:31.669
imagination of uh of people that are so


00:28:31.679 --> 00:28:33.350
interested in astronomy and space


00:28:33.360 --> 00:28:36.389
science. So, I suppose we should start


00:28:36.399 --> 00:28:39.269
by reminding people what a graar is


00:28:39.279 --> 00:28:40.470
supposed to be because I don't think


00:28:40.480 --> 00:28:42.389
we've ever found one.


00:28:42.399 --> 00:28:45.110
>> No, that's correct. Um, I'm I'm going to


00:28:45.120 --> 00:28:47.830
read from uh that font of all knowledge,


00:28:47.840 --> 00:28:51.110
Wikipedia, who I do subscribe to uh


00:28:51.120 --> 00:28:52.630
despite the fact that they keep asking


00:28:52.640 --> 00:28:54.389
me for another subscription. Anyway,


00:28:54.399 --> 00:28:55.830
that's probably because I've got more


00:28:55.840 --> 00:28:58.310
than one username. Never mind. Let me


00:28:58.320 --> 00:29:01.350
read from Wikipedia. In astrophysics,


00:29:01.360 --> 00:29:04.310
the graar which is a blend word of


00:29:04.320 --> 00:29:07.909
gravitational vacuum star is an object


00:29:07.919 --> 00:29:11.909
hypothesized in a 2001 paper by Pavl O


00:29:11.919 --> 00:29:16.070
Mazour and Emil Moah as an alternative


00:29:16.080 --> 00:29:19.190
to the black hole theory. It has the


00:29:19.200 --> 00:29:21.830
usual black hole metric outside of the


00:29:21.840 --> 00:29:23.590
horizon and a metric is just a way of


00:29:23.600 --> 00:29:27.029
describing space but ditter metric


00:29:27.039 --> 00:29:30.149
inside and that's a different one. Don't


00:29:30.159 --> 00:29:32.630
worry about that. A typical grav star is


00:29:32.640 --> 00:29:36.230
as big as London but weighs 10 solar


00:29:36.240 --> 00:29:37.269
masses.


00:29:37.279 --> 00:29:38.070
>> Why?


00:29:38.080 --> 00:29:40.310
>> Yeah. So a neutron star would be about


00:29:40.320 --> 00:29:42.950
the size of London but weigh one solar


00:29:42.960 --> 00:29:44.310
mass basically.


00:29:44.320 --> 00:29:46.389
>> Didn't they find one in a sewer? Um,


00:29:46.399 --> 00:29:47.990
they called it a fatburgg or something.


00:29:48.000 --> 00:29:50.710
>> Fatburgg. That's right. Yeah. Which was


00:29:50.720 --> 00:29:52.710
just about to turn into a graver star.


00:29:52.720 --> 00:29:56.230
Yes. Um, on the horizon there is an


00:29:56.240 --> 00:29:59.190
ultra thin, incredibly tight shell of


00:29:59.200 --> 00:30:03.750
entirely new unique exotic matter named


00:30:03.760 --> 00:30:05.830
Galactic Flubber.


00:30:05.840 --> 00:30:07.590
>> I was close.


00:30:07.600 --> 00:30:09.669
>> You weren't far off. That's right. Which


00:30:09.679 --> 00:30:11.830
is the next thing to a fatburg. Yeah.


00:30:11.840 --> 00:30:13.590
Anyway, continuing to read. This


00:30:13.600 --> 00:30:15.590
solution to the Einstein equations is


00:30:15.600 --> 00:30:18.870
stable and there's no singularities


00:30:18.880 --> 00:30:20.389
which we've just been talking about


00:30:20.399 --> 00:30:23.510
singularities points of zero volume.


00:30:23.520 --> 00:30:25.350
Instead, a grav star is filled with


00:30:25.360 --> 00:30:28.230
either dark energy or with vacuum energy


00:30:28.240 --> 00:30:30.789
but also vacuum


00:30:30.799 --> 00:30:33.590
only the inside one 10 to the 44 times


00:30:33.600 --> 00:30:36.230
denser than the outside. I'm not sure


00:30:36.240 --> 00:30:37.990
how you can have a vacuum that's 10 to


00:30:38.000 --> 00:30:40.710
the 44 times denser than another one,


00:30:40.720 --> 00:30:43.510
but I'll just let that pass. Yes.


00:30:43.520 --> 00:30:46.630
>> Uh, as a bonus, further theoretical


00:30:46.640 --> 00:30:48.549
considerations of grav stars include the


00:30:48.559 --> 00:30:51.269
notion of a nest star, a second graar


00:30:51.279 --> 00:30:54.230
nested within the first one. So, that's


00:30:54.240 --> 00:30:56.149
the technical definition. I bet you're


00:30:56.159 --> 00:30:59.110
no wiser than I am. Um, but the bottom


00:30:59.120 --> 00:31:03.909
line is that um um and I'll read again.


00:31:03.919 --> 00:31:06.549
Mazour and Matahus suggest that the


00:31:06.559 --> 00:31:09.350
violent creation of a grab star might be


00:31:09.360 --> 00:31:11.350
an explanation for the origin of our


00:31:11.360 --> 00:31:14.070
universe and many other universes


00:31:14.080 --> 00:31:15.990
because all the matter from a collapsing


00:31:16.000 --> 00:31:18.310
star would implode through the central


00:31:18.320 --> 00:31:20.789
hole and explode into a new dimension


00:31:20.799 --> 00:31:22.870
and expand forever which would be


00:31:22.880 --> 00:31:25.029
consistent with the con current theories


00:31:25.039 --> 00:31:27.909
regarding the big bang.


00:31:27.919 --> 00:31:31.909
>> Okay. So now that we know what it is.


00:31:31.919 --> 00:31:33.990
>> Yeah. Do you think they exist? And will


00:31:34.000 --> 00:31:35.350
we ever find one?


00:31:35.360 --> 00:31:39.350
>> Uh, no and no, basically. Uh, it's um


00:31:39.360 --> 00:31:42.470
it's a it's a an alternative theory for


00:31:42.480 --> 00:31:43.750
the Big Bang.


00:31:43.760 --> 00:31:46.950
>> Uh, and it's certainly interesting and


00:31:46.960 --> 00:31:50.630
uh I you know I I think um uh GGO's


00:31:50.640 --> 00:31:52.389
asked us to talk about it and now we


00:31:52.399 --> 00:31:56.950
have so so um that's perhaps doing the


00:31:56.960 --> 00:31:59.669
best we can. Um interesting. There's


00:31:59.679 --> 00:32:01.669
there's just one other sentence I might


00:32:01.679 --> 00:32:04.630
like to read. Uh


00:32:04.640 --> 00:32:09.430
uh if I can find it. I've lost it now.


00:32:09.440 --> 00:32:12.310
Oh yeah. The the new dimension that will


00:32:12.320 --> 00:32:15.190
be created in this implosion. The new


00:32:15.200 --> 00:32:18.389
dimension exerts an outward pressure on


00:32:18.399 --> 00:32:21.590
the Bose Einstein condensate layer and


00:32:21.600 --> 00:32:23.509
present prevents it from collapsing


00:32:23.519 --> 00:32:26.230
further. So the Bose Einstein


00:32:26.240 --> 00:32:28.070
condensate, it sounds as though that's


00:32:28.080 --> 00:32:30.870
this thinned crust that it's got rather


00:32:30.880 --> 00:32:33.269
than an event horizon. And a Bose


00:32:33.279 --> 00:32:35.669
Einstein condensate is really


00:32:35.679 --> 00:32:37.190
interesting. I think we've just


00:32:37.200 --> 00:32:39.029
celebrated,


00:32:39.039 --> 00:32:43.669
is it the 30th anniversary of the first


00:32:43.679 --> 00:32:46.870
example of a Bose Einstein condenser


00:32:46.880 --> 00:32:48.549
being produced? I think that's right. I


00:32:48.559 --> 00:32:51.509
think it's 30 years. I think it's 1995.


00:32:51.519 --> 00:32:54.310
Uh what is it? It's a a it's a


00:32:54.320 --> 00:32:56.630
condensation of atoms at very low


00:32:56.640 --> 00:32:59.269
temperature that behave like one quantum


00:32:59.279 --> 00:33:02.149
object. Uh that's the crucial thing. So


00:33:02.159 --> 00:33:04.310
they it's almost like entanglement,


00:33:04.320 --> 00:33:05.909
Andrew, where you've got quantum


00:33:05.919 --> 00:33:07.830
particles being entangled. This is a


00:33:07.840 --> 00:33:09.669
whole bunch of stuff that is so


00:33:09.679 --> 00:33:11.590
entangled it just looks like one quantum


00:33:11.600 --> 00:33:14.310
object and we've we can now create them.


00:33:14.320 --> 00:33:16.470
>> Um so that's what they're saying that


00:33:16.480 --> 00:33:18.149
maybe this thing is made of a Bose


00:33:18.159 --> 00:33:20.389
Einstein condenser. I think this is a


00:33:20.399 --> 00:33:23.590
really good way to end uh the year's uh


00:33:23.600 --> 00:33:25.669
space nuts episode because it is


00:33:25.679 --> 00:33:28.230
completely off the wall and talking


00:33:28.240 --> 00:33:30.789
about stuff that is right at the cutting


00:33:30.799 --> 00:33:32.389
edge of physics which I love


00:33:32.399 --> 00:33:34.549
>> indeed. Uh thank you for your questions


00:33:34.559 --> 00:33:37.509
Ggo and uh hope you're well. Uh good to


00:33:37.519 --> 00:33:39.269
hear from you. You sent in questions


00:33:39.279 --> 00:33:41.350
before so it's nice to catch up. Uh in


00:33:41.360 --> 00:33:45.110
fact I think um I think Isht uh has sent


00:33:45.120 --> 00:33:47.190
questions in before as well. But uh


00:33:47.200 --> 00:33:48.389
yeah, thank you for your questions


00:33:48.399 --> 00:33:50.389
everybody for uh contributing to this


00:33:50.399 --> 00:33:52.710
the final episode of 2025. Keep the


00:33:52.720 --> 00:33:54.630
questions coming in because we're coming


00:33:54.640 --> 00:33:55.750
back


00:33:55.760 --> 00:33:57.350
>> next year and we'll we'll need some


00:33:57.360 --> 00:33:59.110
fresh stuff cuz we're we're down to the


00:33:59.120 --> 00:34:02.310
last one or two um which I didn't use


00:34:02.320 --> 00:34:03.830
because they all came from the same


00:34:03.840 --> 00:34:05.590
source and I like to spread the love a


00:34:05.600 --> 00:34:07.350
bit. So um we'll get into those next


00:34:07.360 --> 00:34:09.349
year. Uh if you go to our website if


00:34:09.359 --> 00:34:11.349
you'd like to send a question in, click


00:34:11.359 --> 00:34:14.069
on the AMA link at the top and you can


00:34:14.079 --> 00:34:16.629
send text and audio questions there. As


00:34:16.639 --> 00:34:18.710
always, please remember to tell us who


00:34:18.720 --> 00:34:20.470
you are and where you're from. While


00:34:20.480 --> 00:34:22.550
you're at on the website, um check out


00:34:22.560 --> 00:34:24.790
how you might be able to support us uh


00:34:24.800 --> 00:34:27.589
through various channels. Um whatever


00:34:27.599 --> 00:34:29.750
you choose or don't choose to, we're not


00:34:29.760 --> 00:34:31.510
going to make you do it. Uh you can


00:34:31.520 --> 00:34:32.869
check out the shop as well. That's


00:34:32.879 --> 00:34:35.669
another way of supporting us. And so on


00:34:35.679 --> 00:34:37.909
and so forth. Um, while I


00:34:37.919 --> 00:34:39.510
>> I think Andrew, while you were talking


00:34:39.520 --> 00:34:40.869
about the questions, I think we've got a


00:34:40.879 --> 00:34:43.270
pending one still from Rusty, which we


00:34:43.280 --> 00:34:44.470
should


00:34:44.480 --> 00:34:46.869
>> I'm sure we'll take it next year.


00:34:46.879 --> 00:34:50.230
>> Yes. Yes, I I recall that. But, um, we I


00:34:50.240 --> 00:34:51.750
thought we'd sit on it till the new year


00:34:51.760 --> 00:34:53.270
because reading the question will


00:34:53.280 --> 00:34:59.190
actually take the pulp of the episode.


00:34:59.200 --> 00:35:00.550
>> Thank you, Andrew. Sorry to interrupt


00:35:00.560 --> 00:35:02.630
you there. That's okay. No, it's okay.


00:35:02.640 --> 00:35:04.790
Um, I just want to say thank you to you,


00:35:04.800 --> 00:35:06.790
Fred. Um,


00:35:06.800 --> 00:35:09.990
And and I should also um thank Jonty


00:35:10.000 --> 00:35:12.310
because he he did a fair chunk of the


00:35:12.320 --> 00:35:16.470
show and we also had our guest presenter


00:35:16.480 --> 00:35:18.550
Heidi while I was away. So thank you to


00:35:18.560 --> 00:35:21.109
Heidi for uh her amazing contribution


00:35:21.119 --> 00:35:24.630
because uh it really saved my uh my back


00:35:24.640 --> 00:35:27.270
because um there was probably no way in


00:35:27.280 --> 00:35:28.710
the world I could have recorded from a


00:35:28.720 --> 00:35:30.870
cruise ship and got away with it. But um


00:35:30.880 --> 00:35:32.950
yeah, fantastic. Uh we've got a great


00:35:32.960 --> 00:35:37.030
team. Um and and you know bring on the


00:35:37.040 --> 00:35:39.430
next uh the next year of Space Nuts. And


00:35:39.440 --> 00:35:41.109
I look I give him a hard time every


00:35:41.119 --> 00:35:42.870
week. I do. But I've got to say thanks


00:35:42.880 --> 00:35:46.230
to Hugh in the studio for his um amazing


00:35:46.240 --> 00:35:48.950
work. It's not just our podcast that he


00:35:48.960 --> 00:35:50.630
looks after. He's got a whole stable of


00:35:50.640 --> 00:35:53.109
them. And uh it's it's basically a


00:35:53.119 --> 00:35:55.349
full-time job trying to run all this. uh


00:35:55.359 --> 00:35:57.750
and you know there's not much money in


00:35:57.760 --> 00:36:00.710
it but uh uh there's certainly joy in


00:36:00.720 --> 00:36:03.829
putting our skills into something uh in


00:36:03.839 --> 00:36:06.950
our semi-retirement um from from radio.


00:36:06.960 --> 00:36:09.829
So um yeah but uh also without the


00:36:09.839 --> 00:36:12.790
audience we would be nothing. So we send


00:36:12.800 --> 00:36:16.550
out our um uh our thanks. We are so


00:36:16.560 --> 00:36:19.430
grateful to have you behind us. And I do


00:36:19.440 --> 00:36:21.589
keep an eye on the audience through the


00:36:21.599 --> 00:36:24.230
Space Nuts podcast group on Facebook


00:36:24.240 --> 00:36:26.310
because they uh they spend a lot of time


00:36:26.320 --> 00:36:27.910
there talking to each other, sharing


00:36:27.920 --> 00:36:31.190
pictures uh and uh posing unusual


00:36:31.200 --> 00:36:32.790
questions which occasionally we will


00:36:32.800 --> 00:36:35.430
bring up on the show. And special thanks


00:36:35.440 --> 00:36:37.030
to our sponsors. We've had a few


00:36:37.040 --> 00:36:38.790
sponsors who've been with us for quite


00:36:38.800 --> 00:36:41.349
some time now and and you know obviously


00:36:41.359 --> 00:36:42.950
we're doing something right if they're


00:36:42.960 --> 00:36:45.510
willing to stick with us. So very much


00:36:45.520 --> 00:36:49.190
appreciated. Uh thank you Fred. Um thank


00:36:49.200 --> 00:36:53.349
you uh Jordy and um we'll talk to you in


00:36:53.359 --> 00:36:55.109
the new year.


00:36:55.119 --> 00:36:56.790
>> Sounds great. Look forward to it Andrew


00:36:56.800 --> 00:36:58.310
and all the very best for the festive


00:36:58.320 --> 00:36:58.950
season to you


00:36:58.960 --> 00:37:01.990
>> and to you and um thank you very much.


00:37:02.000 --> 00:37:03.670
Professor Fred Watson, astronomer at


00:37:03.680 --> 00:37:05.510
large. And from me, Andrew Dunley, have


00:37:05.520 --> 00:37:07.270
a great Christmas, a happy new year.


00:37:07.280 --> 00:37:10.470
We'll see you in 2026. Until then,


00:37:10.480 --> 00:37:11.349
bye-bye.


00:37:11.359 --> 00:37:14.470
>> Space. your Venus to the Space Nuts


00:37:14.480 --> 00:37:16.710
podcast


00:37:16.720 --> 00:37:19.670
>> available at Apple Podcasts, Spotify,


00:37:19.680 --> 00:37:22.310
iHeart Radio, or your favorite podcast


00:37:22.320 --> 00:37:24.710
player. You can also stream on demand at


00:37:24.720 --> 00:37:26.230
byes.com.


00:37:26.240 --> 00:37:28.230
This has been another quality podcast


00:37:28.240 --> 00:37:32.200
production from byes.com.