Sept. 1, 2024

#448: Galactic Life Cycles, Black Hole Growth & Space Junk Rings

#448: Galactic Life Cycles, Black Hole Growth & Space Junk Rings

Join Andrew Dunkley and Professor Fred Watson in this engaging Q&A episode of Space Nuts, where they dive into fascinating listener questions about the life and death of celestial bodies, black holes, and the mysteries of Space junk.
Episode...

Join Andrew Dunkley and Professor Fred Watson in this engaging Q&A episode of Space Nuts, where they dive into fascinating listener questions about the life and death of celestial bodies, black holes, and the mysteries of Space junk.
Episode Highlights:

  • Life and Death in the Universe: Trevor from Port Macquarie asks about the life cycle of the universe. Could everything eventually collapse into a singularity, leading to another Big Bang? Discover the theories and science behind the universe's expansion and the concept of the "Big Rip."
  • - Growth of Black Holes: David from Texas wonders how black holes grow in mass. Fred Watson explains the process of accretion and the role of the event horizon in this cosmic phenomenon.
  • - Space Junk and Artificial Rings: Mikey from Illinois speculates if SpaceTime debris could form an artificial ring around Earth. Learn about the current state of SpaceTime junk and the potential future of Earth's orbital environment.
  • - Seeing the Milky Way in the UK: Ian from Cambridge asks about the visibility of the Milky Way from the UK. Fred Watson provides insights on the best times and conditions to observe our galaxy from the northern hemisphere.
  • - 00:00:00 This is a Q and A edition of space nuts
  • - 00:01:44 Fred asks two questions about the accelerating expansion of the universe
  • - 00:08:54 Why do black holes grow as they eat? Why do they keep growing
  • - 00:13:08 Andrew Dunkley was wondering about space junk in the future
  • - 00:18:39 Fred: Can you see the Milky Way from the UK on a clear night
  • - 00:22:10 Do you think early spring affects viewing of the skies in any way
  • For more Space Nuts, including the Astronomy Daily continually updating newsfeed, visit our website at spacenutspodcast.com. Follow us on social media at SpaceNutsPod on facebook, X, YouTubeMusic, and TikTok. We love engaging with our community, so be sure to drop us a message or comment on your favourite platform.
  • For more Space and Astronomy News Podcasts, visit our HQ at www.bitesz.com.Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts/support.
  • Stay curious, keep looking up, and join us next time for more stellar insights and cosmic wonders. Until then, clear skies and happy stargazing.

 

 

WEBVTT

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Hello again, thanks for joining us on Space Nuts. Andrew

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Dunkley here, and it's a Q and A edition. That

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means that we're going to answer questions, or we're going

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to pretend to, or we're going to refer them to

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a future episode for possible answering or not, or maybe

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we'll just put them in a bin. I don't know

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what have we got today. We're looking at life and

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death within the universe, not the life or death of

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people or other entities for that matter, but maybe the

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life and death of planets and galaxies and maybe the

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universe itself. What's that all about? Will tell you. We're

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also going to look at how black holes grow. That

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question has been asked. Another question about space junk and

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seeing the Milky Way in the UK. How do you

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do it? Ah, You get a very tall ladder to

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get above all the smog and the clouds. That's what

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I reckon. That's all coming up on this edition of

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Space Nuts.

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Second guidance is in Channel ten nine ignition Space Nuts

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or three two one spaces.

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As when I reported, Bill's good and it's good to

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have Professor Fred Watson here to answer all of those

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because I haven't got a clue. Hello, Fred, Oh yeah, true,

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another of I really, Oh well, we'll do our best.

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We have a homework segment that we occasionally do where

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a question gets too hard. Might take us three or

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four months to get back to you, but we do it.

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We do it.

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What's the rush? Shall we begin? Why not?

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Okay?

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This first question comes from Trevor. Trevor's in Port Macquarie,

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which is up on the mid north coast of New

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South Wales, Australia. Horrible part of the world. Nobody wants

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to live there. I mean, they've got beautiful green trees

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and subtropical forests and white beaches and fishing and why

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would you want to live there? Okay Trevor, Nice to

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get your question. Hi, Andrew and Fred. Everything in the

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universe is born at some point and has a lifespan

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on Earth at the end of their life. At the

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end of their life, plants and animals return to the

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soil from where they came In space, suns and planets

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live and die and eventually become part of the space

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around them once more. So could this be true for

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the entire universe? We think we know that the universe

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was born in the Big Bang, and that it will

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probably die at some point in the future. So I'm

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wondering if, over the eons of time, could the black

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holes that seem to be at the middle of every

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galaxy eventually pull everything currently in the universe back into

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one singularity, at which point we would have another Big

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Bang and a new universe. Would he bought many thanks

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for your program. I listened in bed every night and

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it helps me go off to sleep at least twice

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a week. I'm glad we can do that for you. Drever.

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We put him to sleep for it, that's right, and

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that's something I'm really good at. Boy, I'm sure he

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didn't mean it that way. I'm sure he didn't know. Look, Trevor,

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great to talk to you. You have, as you might know,

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in Port mcquarie a brand new, marvelous science center in

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the middle of town which is being opened a little

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bit later in the year. It's on the site of

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the old observatory there, which I was always very fond

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of and indeed was its patron, and I think I

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might be the patron of the new science center as well. Wonderful, brilliant,

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and so that opens in a couple of months. So

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make sure you go along and check it out, Trevor,

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because you're in pop position to do that up there

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in Port McQuary. And the answer is, well, yes, it's true.

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Everything seems to have a life cycle. And the theory

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that you've mentioned that the gravitational pull of everything in

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the galaxy in the universe might eventually cause the universe

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to collapse back on itself into another singularity, the gibb.

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They're gonnab gibb, that's right, the opposite of the Big Bang.

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That's the name coined by Brian Schmidt before he did

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his nobelp Ice spinning work. We used to we usually

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called it the Big Crunch. The idea was that everything

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would eventually collapse back on itself and would be a

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big Crunch which may have spawned another Big Bang, and

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that would be a you know, a new universe being

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rebuilt born exactly as you've said, Trevor. What basically through

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that or through cold water onto that argument was Brian

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himself and the colleagues in the United States so together

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in nineteen ninety eight discovered that actually the universe, its

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expansion is not slowing down as you would have had

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to have if you're going to get a good nab

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GiB or a big crunch. It's accelerating. So the accelerated

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expansion of the universe really knocks that on the head.

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And it also tells us that there is something in

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the universe that is causing space to accelerate, not just expand,

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but to expand ever more rapidly. And we call that

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dark energy. And if you thought dark matter was a mystery,

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wait till you get to dark energy. We really have

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very little idea of what it is. It's some sort

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of vacuum energy. It's some kind of energy of space itself.

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The more space you get, the more energy you get,

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and it's causing the universe to expand ever more rapidly.

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So it looks as though the universe may never have

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an ending if it just keeps on going and expanding,

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unless the thing that some other people have hypothesized that

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one day space itself might just get so stretched by

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the accelerating expansion that it fractures and you get something

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called the big rip. And the big Rip is another

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possible end to the universe when space itself just gets

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ripped apart.

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Well, yeah, that seems to be the popular opinion at

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the moment, doesn't.

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It It is. Yeah, well, the big rip is a

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little bit hypothesized, but certainly the accelerated expansion is taken

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as fat. Now since that discovery was made, it's not

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just the observations of supernova exploding stars that were what

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allowed that discovery to be made, but many other observations

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of the state of the universe. If I can put

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it that way, imply that the big that the dark

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energy is there.

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Okay, there you are. So in regard to his question

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about life cycles in the universe, we are seeing that

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and we I mean, eventually everything's going to finish in

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terms of the physical forms, the stars, the galaxies, the

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black holes themselves may well billions upon billions of years

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evaporate because they are burning their energy. They're getting weaker

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over time. It's just a very slow process. But the

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universe as a whole, that's a different question.

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I suppose, Yes, that's right. You know, so you're right

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in that the kind of life and death processes that

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involve stars and stars are the you know, the main

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kind of matter in the universe apart from dark matter.

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They're the way we detect matter in the universe. Anyway,

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that life and death cycle is well known. And when

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you look forward some hundred billion years or so, all

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you've got is dark remnants, remnants black dwarfs with them,

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remnants of stars, and probably a lot of black holes

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as well. So everything's kind of dead and dormant. There's

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no black holes are not feeding because there's nothing for

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them to feed on, and so it becomes a very

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boring universe. Indeed, and maybe a big rip would be

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the fitting end for a universe like that.

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And once everything's expanded beyond our capacity to see them,

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no astronomers, Fred, damn, Yeah, you'll have to retire then.

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Yeah, I'm just a dying greed. That's terrible.

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How many gazillion years away is that?

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Yes? Anyway, yeah quite a few.

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We're in no rush. Thank you, Trevor. I hope you're

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enjoying Port McQuary. Lovely, lovely place it is. Let's go

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to our next question. This one comes from David.

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Hey Fred and Andrews. David from Singing Texas, just sitting

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here in bed thinking about black holes and questioning how

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is it that black holes grow like want? A black

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hole over time becomes a super massive black hole that

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was it that they grow? Because if they're gravity can

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sucking even late and they're supposed to be infinitely dense,

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why don't they just stay the same size and just

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continue eating? Why do they Why do they grow as

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they eat? Like? What is it that's growing? Thank you guys,

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love the podcast.

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Thank you David. It's it's it's a tough nut to crack,

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isn't it the old black hole? What? What's it eating?

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How is it getting bigger? They eat each other or

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they merge and we know that, but yeah, it's a

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good question. Why don't they just stay the same size?

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Why do they keep growing?

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What?

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What is causing that? What? What are they actually eating?

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Well, yes, I think that the issue is not so

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much what they're eating, because we do know that the

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gobble of anything that's well basically yes, that's right, Not

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that they go chasing around the universe to find them.

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Now they need a trapdoor spider, aren't they.

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It's yes, yes, or indeed a huntsman spider which also yes,

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and just grabs things. But so that all goes into

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the black hole, All that debris, stars, gas, dust, other

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black holes occasionally all goes into the black hole apart

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from what's shot out, by the way, by the magnetic

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fields that give you the jets from an active black hole.

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But the questions really about why doesn't it grow? Now,

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it doesn't grow in physical dimensions because by definition, a

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black hole has zero dimensions. It's a singularity, and so

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its volume is zero. And we know, I think the

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way we define a black hole is a point in

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space of infinite density. So it's density is infinite. Now

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density is mass over volume. Density is infinite because volume

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is zero and you're dividing something by zero, which produces infinity.

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That's the density. But that says nothing at all about

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its mass. And the mass is what changes. So it's

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not the size of the black hole, but it's mass

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that changes. They do grow, but they grow in mass,

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and that's how we get the super massive black holes

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because they've been at it for a long time and

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creating this material. So yeah, so they do grow. They

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don't get physically bigger, their mass gets bigger, and in turn,

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the event horizon gets bigger. So that's the bit that

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delineates where you can't penetrate. Nothing can penetrate out of it.

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Not even light is the event horizon, and so as

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a black hole gets big, it's event horizon grows and

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grows and grows, even though it's still a singularity, but

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its mass is going up and that causes the event

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horizon to swell. Okay, yep.

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And if you can do this experiment at home by

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eating one hundred doughnuts exactly, the same thing increases.

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It does, but usually your volume does as well. You

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do that, Yes, I will do that any further.

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Okay, fair enough. So what was the answer to the question.

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The mass increases, but the black hole don't. The dimensions don't.

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The dimensions of the event horizon do because they're linked

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to the mass. So it's the mass that increases.

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Okay, there you go, David.

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You can go to sleep now sitting in bed trying

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to figure out black holes. That's that's self inflicted torture.

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That is that this at least somebody's trying to figure

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it out. A lot of people trying to figure out. David,

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Thanks for the thanks for the question. Lovely to hear

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from you, and Hopaul as well.

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In Texas.

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

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Three Space Nuts.

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Now, Fred, we've got another audio question. This one a

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little closer to home from Mokey.

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Hey, Brad, Hey, Andrew, This is Nike from Illinois. Again.

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I was wondering about space junk. There's a lot of

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it around Earth right now, and there's only going to

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be more, you know, come the future and if nothing

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ever gets done of it. I was wondering I's somewhere

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and maybe the distant future, all of this space junk

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would kind of coalesce and the Earth would maybe have

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its own artificial ring system, kind of like Saturn, but

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just instead of ice, rock and dust, it's junk. Yeah,

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just something that kind of cross my main I wonder

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what you go to think about it?

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Thanks, guys.

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00:14:02.840 --> 00:14:06.600
Yeah, that's a really interesting sort And I mean, it's

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out there. Some of it re enters, some of it

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burns up, some of it's just floating around out there,

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and it can be as small as a fleck of paint,

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but it's moving at a rapid speed, and it has

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had a few close calls and caused a few problems

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from time to time in terms of dealing with it.

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It's every nation's responsibility to look after their own stuff,

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isn't it, or every entities responsibility although that's only a

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recent law and we're still you know, grappling with it.

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We've been experimenting with ways to collect this stuff. But

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I think there's just too much stuff.

241
00:14:44.279 --> 00:14:47.399
Well it's not that there's too much, it's that it's

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kind of spread all over the place. Yeah, and space

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is big, as Douglas Atoms puts it. But you know,

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just thinking about this his point, and in a way,

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there are already has a ring of debris because it's

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around it's the geostationary satellite ring. That's where there are

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very large numbers of satellites. I don't know the total

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number that's in geostationary orbit, but it's quite large. And

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beyond that there is what they call the graveyard orbit,

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where GET stationary satellites have to be pushed out into

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a graveyard orbit once their useful life is over. And

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it's a fairly stable orbit, one that's not you know,

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being perturbed so that it will so that a satellite

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will collide you with another satellite. So so we've already

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got a ring, the GET stationary satellite ring. Most of

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them are in one piece because we use them every

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day for communications. In terms of the lower orbit and

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mid Earth orbits spacecraft. Yes, there is a lot of

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debris around because these spacecraft collide with one another from

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time to time. It's, as you said, flex of paint,

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everything upwards from flex of paint. And it just begs

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the question whether at some time in the future they

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would actually coalesce into a ring, that the orbits of

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these things would flatten out, so that rather than having

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orbits that all inclinations are going all around the Earth,

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so the Earth is like inside a shell of space.

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Debry whether it would flatten out into a ring, and

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I suspect it would in the very long term that

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you would have with a ring of space junk. However,

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we're a long way from that. I think the thing

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about the lower orbit stuff is that that will burn

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up before it before we ever get to that stage.

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So it did you know they'll re enter and burn

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up and cause pollution in the upper atmosphere, which we

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now know is happening, detecting aliminium and other stuff like

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that in the upper atmosphere that comes from re entering spacecraft,

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But that's a vapor rather than a solid entity like

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a ring. So I think the answer to your question,

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Mike he is. We've got a ring already, and most

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of it it's useful, but some of it's not.

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No, and long term, maybe some of the stuff that

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is orbiting by default and won't return to Earth may

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well become a ring. Yes, that's right, assuming we don't

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find a good way to clean it up in the meantime.

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Yeah, I mean we could. You know, there's many projects

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that have been launched to and some have actually been

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launched into space, but they're you know, ways that you

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can either throw a grappling island or a net or

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something at a piece of space debris and slowly down

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so it does re enter the atmosphere. That's becoming or

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maybe it's too early to say it's becoming, but it

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will become a standard procedure. I think, especially for large

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pieces of debris that if they re entered in a

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noncontrolled fashion, they could do damage. I think that's going

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to be the norm. It's also the norm, as you

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hinted at, that any any nation that launches anything into space,

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or any organization that launches anything to space, has to

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demonstrate that they've built in a way of deorbiting it.

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In other words, they can get rid of it and

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that I think has been in place for quite a

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few years now, so in the long term we're in

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better shape than we are at the moment. Hopefully the

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space junk situation will improve.

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Indeed.

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00:18:36.720 --> 00:18:40.160
All right, great question, Mikey, Thank you very much. One

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00:18:40.200 --> 00:18:43.319
more question, possibly two. I don't know how we'll go

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00:18:43.400 --> 00:18:46.720
for time, but we've got a question without notice from

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00:18:46.920 --> 00:18:50.839
YouTube I assume, or something to that effect. But this

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00:18:50.880 --> 00:18:54.160
one coming from Ian who is in Cambridge. Hi, Andrew

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00:18:54.200 --> 00:18:56.680
and Fred. I asked a question last year about not

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00:18:56.759 --> 00:18:59.960
being able to see the Milky Way. I still haven't

312
00:19:00.079 --> 00:19:02.839
seen the Milky Way here in the UK. However, there

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00:19:02.839 --> 00:19:06.079
are some photos on social media showing the Milky Way

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00:19:06.160 --> 00:19:10.519
high in the sky above Stonehenge. Are these genuine? I

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00:19:11.000 --> 00:19:14.519
would have thought from the UK perspective the Milky Way

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00:19:14.960 --> 00:19:17.519
would be low in the southern sky. Thanks for the

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00:19:17.519 --> 00:19:18.359
great podcast.

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00:19:18.519 --> 00:19:18.799
Ian.

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00:19:20.319 --> 00:19:23.519
Well you're from the UK, Fred, so you know the

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lie of the land and the lie of the stars,

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00:19:27.559 --> 00:19:30.880
or the lie of the stars in perspective to the

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00:19:31.680 --> 00:19:35.559
positioning of the northern hemisphere. Can you see the Milky

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00:19:35.559 --> 00:19:37.480
Way from the UK even on a clear.

324
00:19:37.359 --> 00:19:44.240
Night you can, and the Milky Way it goes all

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00:19:44.279 --> 00:19:47.640
the way around the sky, so everywhere on Earth we'll

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00:19:47.680 --> 00:19:51.559
see it at some point. The best time to look

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00:19:53.079 --> 00:19:56.839
from those two kind of good times, I suppose from

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00:19:56.880 --> 00:20:01.039
the northern hemisphere is the midd of winter, because the

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00:20:01.079 --> 00:20:04.400
Milky Way stretches right up, goes past to Ryan, goes

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00:20:04.440 --> 00:20:07.480
through Cassiopia, all those constellations. It goes right basically from

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north to south across the sky. It's in the middle

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00:20:14.119 --> 00:20:16.880
of the year as well. You can see it quite well.

333
00:20:17.200 --> 00:20:22.920
I think what Ian is really meaning though, is the

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00:20:22.960 --> 00:20:25.640
center of our Milky Way galaxy, which is the brightest

335
00:20:25.680 --> 00:20:28.920
part of the Milky Way, which goes directly overhead here

336
00:20:28.920 --> 00:20:34.440
in Australia, but it only skirts the southern horizon in

337
00:20:35.119 --> 00:20:37.680
the northern Hemisphere, certainly at the latitude of the UK,

338
00:20:38.920 --> 00:20:41.480
so you can see it. I've observed Sagittarius, which is

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00:20:41.480 --> 00:20:46.279
where the galactic center is. I've observed it from Scotland actually,

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00:20:46.519 --> 00:20:49.880
but it's been very very low down in the sky.

341
00:20:49.880 --> 00:20:52.240
Good to see because there's pollution and light pollution and

342
00:20:52.279 --> 00:20:55.759
everything there. But the problem but the Milky Way itself

343
00:20:55.799 --> 00:20:57.759
goes all the way around the sky and is visible,

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00:20:57.839 --> 00:21:00.759
as I said, best in midwinter in fact, in the

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00:21:00.759 --> 00:21:03.359
middle of summer, it's to date, there's too much daylight,

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00:21:04.119 --> 00:21:06.960
the nights last too long or the days last too long.

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00:21:07.640 --> 00:21:11.119
So but the main thing is to be away from

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00:21:11.240 --> 00:21:15.039
light pollution. And that's because the Milky Way, has seen

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00:21:15.079 --> 00:21:17.440
from the northern hemisphere, is fainter than it is in

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00:21:17.480 --> 00:21:20.279
the south. Because we've got the galactic center where it

351
00:21:20.359 --> 00:21:23.920
is richest milky ways, it is pricest. So you are

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00:21:24.359 --> 00:21:26.039
right in that the Milky Way is fainter in the

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00:21:26.039 --> 00:21:29.799
northern hemisphere, but it's still visible and on a dark

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00:21:29.920 --> 00:21:33.039
night away from city lights, is pretty impressive. So that

355
00:21:33.400 --> 00:21:37.200
picture of the other Stonehenge would not necessarily be a fake.

356
00:21:37.680 --> 00:21:41.119
Okay, I've looked at a few here, and one of

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00:21:41.160 --> 00:21:44.559
them referring to a photograph on a summer night at

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00:21:44.599 --> 00:21:49.480
Stonehenge and it's showing the Milky Way vertical. How does

359
00:21:49.480 --> 00:21:50.160
that say under you?

360
00:21:50.440 --> 00:21:53.240
That will be right. It will be vertical as it

361
00:21:53.279 --> 00:21:55.279
is in winter as well and midwinter night.

362
00:21:56.000 --> 00:22:00.480
Okay, you have it ian, so it's probably genuine. There'd

363
00:22:00.480 --> 00:22:02.119
be a lot of others out there that have been

364
00:22:02.160 --> 00:22:07.759
constructed from superimposed photographs, but yes, it is a possibility,

365
00:22:09.000 --> 00:22:11.559
and yeah, thanks for the question one quick one without

366
00:22:11.640 --> 00:22:17.480
notice fread comes from I think TDJ has a message

367
00:22:17.559 --> 00:22:19.720
just before it's just got home from work. Do have

368
00:22:19.759 --> 00:22:22.640
a question? Does the early spring effect viewing of the

369
00:22:22.680 --> 00:22:23.920
skies in any way?

370
00:22:25.359 --> 00:22:30.440
Yeah? Only weather wise. You know, we've got probably warmer

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00:22:30.480 --> 00:22:37.559
weather that should produced drier atmospheres and give you a

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00:22:37.599 --> 00:22:40.759
better view. I noticed, I've just I've got a bit

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of a weather station on the wall. I noticed the

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00:22:43.319 --> 00:22:45.960
pressures low. Actually at the moment it's much warmer than

375
00:22:46.000 --> 00:22:50.119
it should be in winter. Yeah. The air though, is

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00:22:50.240 --> 00:22:52.640
very dry compared with what it normally is like, and

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00:22:52.680 --> 00:22:57.039
that normally gives you better viewing, less twinkling in the

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00:22:57.079 --> 00:23:00.839
sky because the amount of turbul it's in the atmosphere

379
00:23:00.839 --> 00:23:02.960
settles down when the when the air is dry.

380
00:23:03.599 --> 00:23:06.119
How about that? There you go to DJ thanks for

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00:23:06.160 --> 00:23:08.960
the question at the last minute, and he's in Sydney

382
00:23:08.960 --> 00:23:12.400
as well for it probably probably cross the road from you,

383
00:23:13.559 --> 00:23:15.559
indeed wrestling goannas.

384
00:23:16.519 --> 00:23:17.200
Yes, that's right.

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00:23:18.400 --> 00:23:21.519
And a reminder to anybody who wants to send in

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00:23:21.559 --> 00:23:23.599
a question to us to go to our website because

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00:23:23.680 --> 00:23:27.279
that's where you send them and you can do text questions.

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00:23:27.880 --> 00:23:30.599
Just click on the a m a tab or link

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00:23:30.640 --> 00:23:33.240
at the top. You can also send audio questions that

390
00:23:33.319 --> 00:23:36.279
way or on the right hand side where you would

391
00:23:36.640 --> 00:23:40.720
usually be send us your voice message, and it's not

392
00:23:40.759 --> 00:23:43.599
there today. I don't know what happened to that. Probably

393
00:23:43.599 --> 00:23:46.400
my computer doing silly bugger things like it tends to.

394
00:23:46.799 --> 00:23:49.400
But yes, we welcome your questions for our Q and

395
00:23:49.480 --> 00:23:53.200
A episodes of Space Nuts. Keep them coming. Thanks for it.

396
00:23:53.279 --> 00:23:54.680
As always, it's a great pleasure.

397
00:23:55.759 --> 00:23:59.039
Two or two Andrew, we struggled through and we've got

398
00:23:59.039 --> 00:24:00.000
some good answers there.

399
00:24:00.079 --> 00:24:02.559
Think yeah, I think so. And we made them all

400
00:24:02.640 --> 00:24:05.359
up as we went along. We didn't even have to

401
00:24:05.400 --> 00:24:08.400
sit down before the show and work out fake answers.

402
00:24:08.480 --> 00:24:11.759
We made them up as we went along. It was brilliant.

403
00:24:12.200 --> 00:24:13.119
We're getting better at this.

404
00:24:13.839 --> 00:24:14.359
Thanks for Red.

405
00:24:14.680 --> 00:24:19.039
We'll see a zooon. Fred Wat's an astronomer at large.

406
00:24:19.039 --> 00:24:23.720
Thanks to here in the studio who sent us one question. Yeah,

407
00:24:23.759 --> 00:24:26.079
we can't tell you anything about that at all, Fred,

408
00:24:26.359 --> 00:24:30.279
for here, we don't know the answer. Talk to your

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00:24:30.279 --> 00:24:34.400
electricity provider and from me from me Andrew Dunkley. Thanks

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00:24:34.440 --> 00:24:36.559
for your company. We'll see you again soon on another

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00:24:36.680 --> 00:24:38.279
episode of Space Nuts.

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00:24:38.319 --> 00:24:42.799
Bye bye, you'll be listening to the Space Nuts podcast,

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00:24:44.440 --> 00:24:50.480
available at Apple Podcasts, Spotify, iHeartRadio, or your favorite podcast player.

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00:24:50.680 --> 00:24:53.799
You can also stream on demand at bides dot com.

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00:24:54.000 --> 00:24:59.200
This has been another quality podcast production from nights dot com.
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