Andrew Dunkley: Hello again.

Thanks for joining us.

This is Space Nuts Q and A edition.

My name is Andrew Dunkley.

This will be our last official show for 2025.

We'll go into a short recess and be back with you early in the new year.

but we've got some questions to nail down before any of that happens.

And we've got a whole bunch of topics that seem to have stirred the imaginations of our audience.

Andrew wants to know about time dilation of stuff.

Stars.

Adriano is talking black holes becoming stars.

Ishtok is wanting to ask about free space.

I always thought it was expensive, especially all the space around where we live.

Yo.

And Gergo, Redshift and Gravastars.

We will tackle all of that in this edition of space nuts.

15 seconds.

Guidance is internal.

Professor Fred Watson: 10, 9.

Ignition sequence.

Star space nuts.

Andrew Dunkley: 5, 4, 3, 2.

Professor Fred Watson: 1.

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

Andrew Dunkley: Space nuts.

Astronauts report it feels good.

And here he is again.

It's professor Fred Watson, astronomer at large.

Hello Fred.

Professor Fred Watson: Hello Andrew.

Andrew Dunkley: Good to see you again.

Professor Fred Watson: Fancy seeing you here.

Andrew Dunkley: How odd.

How strange.

Professor Fred Watson: How strange.

Andrew Dunkley: getting ready for your Christmas break.

I mean you've just come back from a break so you'd be, you know, probably feeling rather relaxed.

Professor Fred Watson: Well, no, because only the last six days weren't work.

Yeah.

So, no, it's not quite true because we did have some time off with my family in Scotland.

but we did have a proper holiday at the end of our trip.

But yes, we did two months of pretty hard work actually.

We had a tour in Japan and then a conference in Ireland and a few other things like that that kept us busy.

So if you, if you want.

Andrew Dunkley: To call international travel a job, that's, you know, that's fine.

Professor Fred Watson: want to call us work.

if you.

Yeah, but when you've got a tour group, when you got 20 people who you entertained for a month, it's actually three and a half weeks.

it is work.

Andrew Dunkley: Yeah.

Yeah.

Well we've got a similar problem in the coming week or two with four grandchildren that we're.

Professor Fred Watson: To the cave.

Speaker C: Yeah.

Professor Fred Watson: To be honest, I'd rather have 20 tourists than four grandchildren.

Although my grandchildren are now totally self propelled.

But for your Yankee swan, Aggie, she's only, she's, she's nine months yesterday actually.

Anyway, anyway, yes, it's a matter of.

But we.

Yeah.

So the bottom line is we will have a relaxing end of year break.

Andrew Dunkley: I hope very good you mentioned Edinburgh.

Well, our first question comes from Andrew in Edinburgh.

he says, I have a two part question about the gravity and subsequent time dilation that occurs in and around supergiant stars.

If the supergiants can collapse into black holes, then they must have as much or even more mass than the resulting black hole.

Just spread over a much large, larger area.

I guess my question is, is there significant time dilation near these stars or are they simply not dense enough to have meaningful amounts of time dilation?

If they do, it's weird that comes up and a slight follow up would be what about time dilation within the star itself?

Presumably near the core of these stars, the density ramps right up.

Does a large difference in time dilation within a star have any impact on how it behaves?

Hope that all makes sense.

Thanks.

Love the show.

That's Andrew in Edinburgh.

Professor Fred Watson: They're great questions.

I'm just not sure about the first sentence.

If the supergiants can collapse into black holes, then they must have as much or even more mass than the resulting black hole.

Yeah, okay, I've read that properly now.

just spread it maybe.

Andrew Dunkley: I didn't read it properly.

Professor Fred Watson: No, it's all right.

No, it's fine.

so yeah, Andrew's first question.

Is there significant time dilation near these stars?

And the answer is yes.

there would be.

it's, I mean the time dilation in a black hole is so great that to an outside observer, time stops on the event horizon.

for a star because it's spread over a larger volume of space, the time dilation is nowhere near as great.

but time dilation will be something that you would have to take into account if you had, a spacecraft orbiting near a giant star.

the bottom line is with, and time dilation, it's a little bit spooky in the sense that to the star itself and to something, say you've got something in orbit around this star, their time's ticking away at the normal rate.

The time dilation is only what you see from the outside.

Andrew Dunkley: So this is basically the same as we were talking about in the last episode regarding Mars.

Same problem.

Professor Fred Watson: Yes, that's right.

It is the same thing.

Yeah.

So time ticks away normally for the star, but to watch it from the outside, you basically see time ticking away a little bit more slowly.

so they would have time dilation.

M.

Andrew's asking whether they're simply not dense enough to have a meaningful amount of time dilation.

And I don't think that's true.

I think this time dilation is significant, especially if you're looking at microseconds, as we were in the last episode.

yeah, so they do.

And look, you're not talking about time dilation of the kind that was depicted in interstellar where time kind of grinds to a halt almost.

it's a more modest amount of time dilation, but it would actually happen.

And Andrew's follow up question.

What about time dilation within the star itself?

Presumably near the core of these stars, the density ramps right up.

There's a large difference in.

Andrew Dunkley: I'm not going in there to find.

Professor Fred Watson: Out there's a difference in time dilation within a star have any impact on how it behaves.

and there's a curious thing there because as you, get near the core of an object, with spherical symmetry, your gravitational field gets less and less.

and in fact at the center you wouldn't feel any gravity.

And that's because everything's pulling you in the same direction all around.

And so I believe that time dilation will probably stop in the middle of a star.

That might be something I've never thought about before.

maybe that's not true because you're still in a gravitational field.

The fact that it cancels out everywhere.

I'll check that one out actually and try and remember for our, first show next year, because that's a really interesting question.

Time dilation in the center of a star, how does it behave?

Andrew Dunkley: very interesting.

Professor Fred Watson: But there wouldn't be a.

I think the bottom line is there wouldn't be a, a big difference in time dilation from one part of a star to another.

That's, that's what I'm trying to say.

Andrew Dunkley: But he brings up another interesting point.

You've got time dilation around a massive star.

Professor Fred Watson: Yep.

Andrew Dunkley: Then it goes, you know, whatever black hole, the time dilation changes.

Professor Fred Watson: Yes, it does because, as it collapses, the gravitational field increases.

it increases in sort of angle in the sense that, you know, it's a steeper gravitational field as you get as the black hole collapses.

And by that I'm thinking of the gravitational well, you know, this dip in the trampoline sheet.

That's the gravitational well of an object which turns into something like a plug hole with water going around it as a vortex for a black hole.

so that's what I mean by the steepness of the gravitational field.

and yes, it is so steep that the Event horizon delineates where the time dilation becomes, such that time appears to stop on the surface of the event horizon.

Andrew Dunkley: Yeah, I've seen that demonstration done with like a big rubber sheet and they say that that's the time, space time continuum and they put a bowling ball in it and they say.

And that's gravity.

Professor Fred Watson: That's right, yep.

I know, yeah.

Andrew Dunkley: It'S a simple way of explaining it, but that's what it is.

I suppose.

Great.

questions, Andrew.

I hope all is well in Edinburgh.

Fred's home stomping ground.

yep, yep.

I'll give you his address and you can go and rock his roof.

This is Space Nuts with Andrew Dunkley and Professor Fred Watson.

Ah, we have got an audio question.

Fred, this is from Adriano.

Speaker C: Hi guys.

Adriano from Florence in Italy.

I have my first question about black holes.

So if I understood correctly, a star continued to burn his fuel like hydrogen and helium.

And there are nuclear fusions and there is enough energy for the star to fight against its own gravitational pull.

But, at some point there is not enough, fuel and the star collapses into a black hole.

After this, the black hole will start to absorb material like hydrogen and then it should have enough energy, enough fuel to have, nuclear fusions and to fight against the gravitational pull.

But, so why a black hole cannot, turn back into a star?

I'm sure this is not possible, but I cannot understand why.

And also guys, we had a lot of beautiful updates from the princess.

Can we also have some updates from Fred?

Thank you guys.

Andrew Dunkley: Bye bye, Adriano, thank you very much.

Fred gave us his update when he got back, but.

Yeah, your point is well made.

Florence, what a beautiful, beautiful city.

Speaker C: Yeah.

Professor Fred Watson: isn't it just?

Andrew Dunkley: we, we visited Florence a few years ago and it was, it was amazing.

But it was also terrible timing because it was All Saints weekend, which is a four day long weekend and there were like tens of thousands of people there.

You couldn't move.

You absolutely couldn't move.

So, we went to, what was it called, the Ponte Vecchia, and we couldn't get near it.

You just couldn't.

It was it was insane.

Yeah, we didn't know until we got there that's what was happening.

But yeah, we still got to see it.

It was a beautiful place and all those amazing statues and Galileo got, got, got up close with Galileo.

Professor Fred Watson: Very good.

Andrew Dunkley: Yeah, yeah.

Professor Fred Watson: Did you see his?

I think it's his.

It's one of his fingers or his thumb, I can't remember which is on display in the science museum there.

Andrew Dunkley: Oh, no, no, couldn't get near that.

yeah, honestly, it was just mayhem.

But, yeah, understandable though.

all right, so the bottom line with Adriano's question is, why can't a black hole turn back into a star?

yeah, I would think there'd be all sorts of reasons why not.

Professor Fred Watson: Well, that's right.

I think once you've turned into a singularity, as the, you can't double down.

Andrew Dunkley: Sorry that, Professor Fred Watson: You took the words out of my mouth.

No, you didn't.

I mean, all bets are off basically once you, Once you've gone into a singularity.

and so I, think, you know, it's a great thought that, Adriano's had.

I.

And it's never occurred to me before, but, but you know, you're talking about hydrogen, which certainly would get sucked into a black hole because a lot of the gas clouds that, the black hole, accretion disk would draw in and suck into the center, that's hydrogen.

and hydrogen is the raw material of stars.

Why can't nuclear fusion kick in again and drive the star back into being a star rather than a black hole?

And I think the answer is in structure.

so stars have quite a complex structure, to make them work.

with the, core, with all the nuclear burning taking place, then there's a convection zone and then there's a sort of outer layer before you get to the photosphere, the layer that you can see.

when you've put something into a singularity, all structure disappears.

And it almost relates to, an issue that occupied the m.

Mind of Stephen Hawking for a while, which is that does information get lost when it goes into a black hole?

And I think there was some argument with another well known physicist.

In fact, I think they had a bet, which Hawking lost.

because, I think the bottom line was Hawking back that information couldn't come out of a black hole.

But somebody proved a theory that information could come out of a black hole.

I think I've got the right way.

Basically, it's all completely mangled in terms of, we don't understand the physics of what would happen inside a singularity.

We just have no idea what the physical processes would be.

And they almost certainly would rule out hydrogen atoms getting together, and with enough temperature to produce the nuclear fusion that we see in a normal star.

a black hole is a very abnormal object.

Nothing relates to normal in a black hole.

And so I think that is the answer to Adriana's question.

physics doesn't work the way it works on the outside of a black hole, and I think that's why we don't see black holes turning into stars.

Andrew Dunkley: Yeah, well, there's also the fuel issue, like, you know, the star has collapsed because of fuel depletion, has it not?

Professor Fred Watson: Yes, that's right.

But what we're saying and what Adriano is saying is that, among the stuff that is accreted by the black hole, when it's sitting there gobbling stuff up, a lot of that is hydrogen, which is the fuel.

So they're getting more fuel, but they don't any longer have the process to make it turn into something that will deliver energy.

I think that's the bottom line.

Andrew Dunkley: I get it, I get it.

Okay.

great question, though, because, we've been talking black holes for I don't know how long, probably since the very beginning of the time that this podcast began, and I don't think we've ever been asked that question before.

Professor Fred Watson: No, I think that's right.

Andrew Dunkley: Yeah.

Professor Fred Watson: So it's a lot for our.

For our, listeners, doesn't it, that they can produce questions that we've never had before after however many episodes.

It's getting on for 500 now.

Andrew Dunkley: This is 582.

Professor Fred Watson: Oh, 582.

Okay.

Andrew Dunkley: 582.

Speaker C: Yeah.

Professor Fred Watson: Right.

There you go.

Getting on for 600.

Andrew Dunkley: Oh, no, it's not.

I mean, it's happening faster because of time dilation and the fact that we decided to do two episodes a week instead of one.

But.

Professor Fred Watson: But I think it's nuts by definition, isn't it?

I've got a feeling.

Yeah.

Andrew Dunkley: anyway, thank you, Adriano, and hope all is well in the beautiful Florence.

This is Space Nuts with Andrew Dunkley and Professor Fred Watson.

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Three, two, one.

Space nuts.

Our, next question doesn't come from Italy, it comes from Slovenia.

Russian store.

Yeah.

I am listening to your podcast while driving to and from work.

Great show.

I hope you managed to keep control because, you know, this gets a bit crazy sometimes.

I'm curious about.

Wait for it, Fred.

Black holes.

we know that an atom is actually a lot of free space where electrons fly around.

eliminating that, we probably, probably get a neutron star.

Ah, with high density.

But what about a black hole?

How does this work?

Where is the free space, that can be squeezed even further to get a black hole?

get black hole material and density and to calculate the density of the black hole.

Would it be a correct assumption to take the event horizon as the boundary and, based on that, calculate the volume?

Or is it something else?

Thank you.

Best regards.

Ishtok.

another black hole question.

Not surprising.

We get a lot of them.

Professor Fred Watson: We do, yeah.

So, it's a great question and, that's absolutely right.

An atom is a lot of free space, empty space, with a, cloud of electrons doing their quantum thing.

if, you collapse the space down so that only the electrons are pushing the, atoms apart, you've got a white dwarf star, which is called electron degenerate.

and if you get rid of the electrons, then you get a neutron star exactly as Ishtok, says, with very, high density, where only the neutrons keep the thing from collapsing into a black hole.

But with a black hole, well, the free space is basically disappeared down the black hole.

and in terms of its density, you have a definition of a black hole.

one of the definitions is A point in space with infinite density.

So the volume is zero.

See, Jordy thinks that ah, as well.

He does.

Gosh, I don't know what's happening out there, but yeah, I love it.

Andrew Dunkley: We had to hear him from.

Professor Fred Watson: Yeah.

Andrew Dunkley: For the last show of the year.

Professor Fred Watson: That's right.

In full flight.

so.

Yes, so it's a point of infinite density.

So it talks a comment about calculating the density of the black hole.

Would it be a correct assumption to take the event horizon as the boundary?

no, it wouldn't.

The event horizon's just that imaginary point where of no return.

and the volume is zero.

the volume of the black hole is zero, which is how the, the density gets infinite because, mass over density.

Sorry, Mass over volume is density.

The mass is a, ah, is a parameter, but the volume is zero.

I've no idea what's happening out there, Andrew, with Jordy, but he obviously likes this conversation.

Andrew Dunkley: Yes, yes, he does.

He wants in.

dear.

yeah, look, I still don't get black holes receding into the distance.

Yeah, probably chasing a snake.

yeah, go ahead, Andrew.

Professor Fred Watson: No, it's.

Andrew Dunkley: It's hard to get your head around something like a black hole having.

No, no density.

Professor Fred Watson: M.

No.

Andrew Dunkley: In my brain.

Professor Fred Watson: No volume.

Andrew Dunkley: No volume.

Professor Fred Watson: It's got no size.

It's got zero dimensions.

Andrew Dunkley: I mean, we, we give them names based on size and yet it has no size.

Professor Fred Watson: Superlastic.

Yeah, well, but it's the mass that's the thing.

So the mass is defined for a black hole.

It's one of the properties that they have.

There's this thing called the no hair theorem, which I like very much.

Yeah.

And it's about, you know, wouldn't.

Andrew Dunkley: They wouldn't.

Professor Fred Watson: Yeah, that's right.

Which is.

It's about the very few parameters that you can get from a black hole.

I think it's mass, charge and spin.

I think that's all you know about a black hole.

because the volume zero.

And that's why the density zero.

Density is mass over volume, volume zero.

So the density goes to infinite infinity, but you can vary the mass.

And that's why we talk about supermassive black holes and intermediate mass black holes and things of that sort.

Andrew Dunkley: Okay, so what was the answer to the question?

Professor Fred Watson: no.

Andrew Dunkley: Righto.

Professor Fred Watson: What was the question again?

Hang on.

yeah.

Would it be.

Yes.

Would it be correct assumption to take the event horizon as a boundary and use that to calculate the volume?

No.

The event horizon is an imaginary sphere that is where the thing turns black Basically because no light can escape.

Andrew Dunkley: Precisely.

hope that helped Ishok.

Professor Fred Watson: it's a great question.

Andrew Dunkley: It is terrific question.

just a very difficult subject because we just don't know a hell of a lot about black holes.

They're just such a mysterious and weird object.

And, we're still trying to gather information about them and they just keep throwing up these curveballs at us and not letting us in.

Not that you want to go in, but you know what I mean.

Professor Fred Watson: Yes, that's right.

Andrew Dunkley: Yeah.

Professor Fred Watson: Quite soon.

Andrew Dunkley: All right, thanks Ishtok.

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Professor Fred Watson: Space Nuts.

Andrew Dunkley: We have one more question to finish things off for 2025.

And it's a real European flavor for this episode.

This is Gergo.

Greetings gentlemen.

Gergo from Slovakia here.

I have a question about redshifting.

Does it have a limit?

Is there a point beyond which light cannot be stretched any further?

If so, what happens if the light continues to travel through expanding space?

And the second question.

Could you talk a bit about Gravastars?

Do you think they might be real?

thank you for your time and for The Great show.

Speaker C: Bye.

Andrew Dunkley: Thanks, Georgia.

yeah, it's an eclectic mix of nationalities.

This Fabius was.

Yeah, it's terrific.

Professor Fred Watson: Yeah, it's great.

Andrew Dunkley: so two questions he's, thrown into the mix.

yeah.

Is there a limit on redshift?

yeah.

Good one.

Professor Fred Watson: So, yeah, it is a good question.

I mean, so redshift, as a term we define as being due to the expansion of the universe.

and it's slightly different from the Doppler shift.

Doppler, shift is something we understand.

Well, it's the way the light changes wavelength from a moving object.

But with redshift, we're talking about space itself.

Rather than objects moving through space.

We're talking about the way space behaves.

and so it's a much more fundamental thing than the Doppler shift.

So in a sense, there's already a limit to redshift.

but it's one that is exactly related to the age of the universe.

so what I'm thinking of here is the, cosmic microwave background radiation.

That's the wall of radiation which corresponds to the brightness of the Big Bang fireball.

Which we're still seeing.

Because as we look further into space, we look back in time.

So everywhere in space we see this wall of radiation.

Which is now in the microwave region of the spectrum.

Which is why we call it the cosmic m.

Microwave background radiation.

Yeah.

And so, if I remember rightly, that is basically the visible flash of the Big Bang.

Because it was, basically a visible light flash.

It's the visible flash redshifted by, I think, about 1300 times.

So everything in the universe must have a.

That we can observe.

Must have a redshift less than that.

I think 1300 is the number that comes into my mind.

I've looked at this for a long time, but it's visible light, Whose waves have been stretched by that amount to give us microwaves.

So stretched about 1300 times thereabouts.

Now, as the universe expands and time goes on, that number will increase not by much.

Might become 1301 or 1305.

But as time goes on, that number's increasing.

So in a sense, that's a limit to redshift.

physically though, I don't think there is a limit.

You could, you know, if you expand the universe.

If you're talking about 40 billion years into the future.

And the universe is expanding more.

Yes.

The cosmic microwave background.

Is going to be the cosmic long wavelength radio background.

and so, the wavelength Will have stretched more.

So there isn't a physical limit, but there is a, ah, a limit in the real universe, simply because of the age of the universe.

The universe hasn't expanded for long enough for the redshift to be more than about 1300.

Right, okay.

Andrew Dunkley: Yeah, got it.

Professor Fred Watson: Good.

What was the other thing?

Oh, Gravisars.

Andrew Dunkley: Oh, Gravastars.

Yeah, we've had, we've had questions about Gravastars before, more than once.

it seems to be something that sort of captured the imagination of people that are so interested in astronomy and space science.

So I suppose we should start by reminding people what a gravastar is supposed to be, because I don't think we've ever found one.

Professor Fred Watson: No, that's correct.

I'm going to read from that font of all knowledge, Wikipedia, who I do subscribe to, despite the fact that they keep asking me for another subscription.

Anyway, that's probably because I've got more than one username.

Never mind, let me read from Wikipedia.

In astrophysics, a Gravis star, which is a blend word of gravitational vacuum star, is an object Hypothesized in a 2001 paper by Pavel O.

Mazur and Emil Motola as an alternative to the black hole theory.

It has the usual black hole metric outside of the horizon.

And the metric is just a way of describing space, but de sittomatric inside.

And that's a different one, don't worry about that.

A typical gravastar is as big as London, but weighs 10 solar masses.

Yeah.

So a neutron star would be about the size of London, but weigh one solar mass, basically.

Andrew Dunkley: Didn't they find one in a sewer?

they called it a fratberg or something.

Professor Fred Watson: Fatberg.

That's right, yeah.

Which was just about to turn into a gravastar.

Andrew Dunkley: Yes.

Professor Fred Watson: on the horizon there is an ultra thin, incredibly tight shell of entirely new unique exotic matter named galactic Flubber.

Andrew Dunkley: That was close.

Professor Fred Watson: You weren't far off.

That's right.

Which is the next thing to a fatberg.

Yeah.

Anyway, continuing to read this solution to the Einstein equations is stable and has no singularities, which we've just been talking about singularities, points of zero volume.

Instead, Gravastar is filled with either dark energy or with vacuum energy, but also vacuum.

only the inside one, 10 to the 44 times denser than the outside.

I'm not sure how you can have a vacuum that's 10 to the 44 times denser than another one, but I'll just let that pass.

Yes.

as a bonus, further theoretical considerations of gravastars include the notion of a nestar.

A second gravastar nested within the first one.

So that's the technical definition.

I bet you're no wiser than I am.

but the bottom line is that, And I'll read again.

Mazur and Mottola suggest that the violent creation of a gravastar might be an explanation for the origin of our universe and, many other universes, because all the matter from a collapsing star would implode through the central hole and explode into a new dimension and expand forever, which would be consistent with the current theories regarding the Big Bang.

Andrew Dunkley: Okay, so now that we know what it is, do you think they exist and will we ever find one?

Professor Fred Watson: no and no.

Basically, it's, an alternative theory for the Big Bang, and it's certainly interesting.

And, I, you know, I, I think m.

Gago's asked us to talk about it, and now we have.

So, so, that's perhaps doing the best we can.

Interesting.

There's.

There's just one other sentence I might like to read.

if I can find it, I've lost it now.

Oh, yeah.

The new dimension that will be created in this implosion.

The new dimension exerts an outward pressure on the Bose Einstein condensate layer and prevents it from collapsing further.

So the Bose Einstein condensate.

It sounds as though that's this thinned crust that it's got rather than an event horizon.

And the Bose Einstein condensate is really interesting.

I think we've just celebrated.

Is it the 30th anniversary of the first example of a Bose Einstein condenser being produced?

I think that's right.

I think it's 30 years.

I think it's 1995.

what is it?

it's a condensation of atoms at very low temperature that behave like one quantum object.

that's the crucial things.

So it's almost like entanglement, Andrew, where you've got quantum particles being entangled.

This is a whole bunch of stuff that is so entangled it just looks like one quantum object and we can now create them.

so that's what they're saying, that maybe this thing is made of a Bose Einstein condenser.

I think this is a really good way to end, the year's, Space Nuts episode because it is completely off the wall and talking about stuff that is right at the cutting edge of physics, which I love.

Andrew Dunkley: Indeed.

Thank you for your questions.

Gergo and Hope, you're well.

Good, to hear from you.

He's sending questions before so it's nice to catch up.

in fact, I think, I think Ishtok, has sent questions in before as well.

But, yeah, thank you for your questions everybody, for contributing to this, the final episode of 2025.

Keep the questions coming in because we're coming back next year and we'll need some fresh stuff because we're down to the last one or two, which I didn't use because they all came from the same source and I like to spread the love a bit.

So, we'll get into those next year.

But, go to our website if you'd like to send a question in.

Click on the AMA link at the top and you can send text and audio questions there.

As always, please remember to tell us who you are and where you're from while you're at, on the website.

check out how you might be able to support us, through various channels.

whatever you choose or don't choose to, we're not going to make you do it.

you can check out the shop as well.

That's another way of supporting us and so on and so forth.

while I think.

Professor Fred Watson: Andrew, while you're talking about the questions, I think we've got a pending one still from Rusty, which we just wish to.

We'll take it next year.

Andrew Dunkley: Yes, yes, I recall that.

But, we.

I thought we'd sit on it till the new year because reading the question will actually take the pulp of the episode.

Professor Fred Watson: Thank you, Andrew.

Sorry to interrupt you.

Andrew Dunkley: That's okay.

No, that's okay.

I just want to say thank you to you, Fred.

and, and I should also, thank Jonti because he, he did a, fair chunk of the show and we also had our guest presenter, Heidi while I was away.

So thank you to Heidi for her amazing, contribution because, it really saved my, my back because, there's probably no way in the world I could have recorded from a cruise ship and got away with it.

But, yeah, fantastic.

we've got a great team.

and, and you know, bring on the next, the next year of Space Nuts.

Speaker C: And I.

Andrew Dunkley: Look, I give him a hard time every week, I do.

But I've got to say thanks to Huw in the studio for his, amazing work.

It's not just our podcast that he looks after.

He's got a whole stable of them and it's it's basically a full time job trying to run all and you know there's not much money in it but there's certainly joy in putting our skills into something in our semi retirement from, from radio.

So.

Yeah.

But also without the audience we would be nothing.

So we send out our our thanks.

We are so grateful to have you behind us and I do keep an eye on the audience through the Space Nuts podcast group on Facebook because they they spend a lot of time there talking to each other, sharing pictures, and posing unusual questions which occasionally we will bring up on the show.

And special thanks to our sponsors.

We've had a few sponsors who've been with us for quite some time now and, and you know, obviously we're doing something right if they're willing to stick with us.

So very much appreciated.

thank you Fred.

thank you Jordi and, and we'll talk to you in the new year.

Professor Fred Watson: Sounds great.

Look forward to it Andrew.

And all the very best for the festive season to you.

Andrew Dunkley: And to you Imani.

thank you very much, Professor Fred Watson, Astronomer at large, and from me, Andrew Dunkley.

Have a great Christmas.

A happy new year.

We'll see you in 2026.

Until then, bye bye.

You'll be listening to the Space Nuts podcast available at Apple Podcasts, Spotify, iHeartRadio or your favorite podcast player.

You can also stream on demand@bytes.comm this.

Professor Fred Watson: Has been another quality podcast production from bytes.com