Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #360: Collaboration vs. Competition: Advancing Space Exploration Together & Other Space Questions

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#360: Collaboration vs. Competition: Advancing Space Exploration Together & Other Space Questions · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
Hi once again, and thank you for joining us. This is Space Nuts.
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My name is Andrew Dunkley, your host. It's great to have your
0:06
company. And as this is the three hundred and sixtieth episode, like we
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do every fifth episode, it is dedicated one hundred percent to audience questions.
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We will be covering black holes, strangely enough, exo planets, XO asteroids,
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time dilation, red shift, the balance of power in the space race
0:27
as it stands now and what we think about that and metallicity all coming up
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on this episode of Space Nuts. Channel nine. Magnian sequenced Space Nuts three
0:45
two Space Nuts as an actual board it deal good. Yes, And joining
0:53
me to answer all questions known to mankind is Professor Fred Watson, Astronomer at
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Large. Hello Fred, it might be not just human kind, but it
1:03
might be alien kind as well. It could be Yeah, it's all sorts
1:07
of possibilities, indeed, But yes, how have you beaten? Or not
1:12
so bad? Thank you? My nearest and dearest has got the most awful
1:17
cold, so I expected them to be soon. So yeah, who knows
1:21
what I'll be what stays I'll be in next time we speak? Yes,
1:23
well, fingers crossed that you managed to avoid it. My dad's got at
1:27
the moment. Two was down Newcastle Away to celebrate my brother's sixtieth birthday last
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week. So he co hosts with Tim Gibbs Astronomy Daily. So yeah,
1:41
we had a good time. It's nice to catch up with family. And
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I played golf in the most brutal wind known to mankind or humankind last Saturday.
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I don't know if it was windy in Sydney. I imagine it was,
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but yeah it was. It was O God, I should blow the
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dog off a chain. Then I played. I played golf in at a
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lovely course called the Vintage in the hunt of Valley. All right. Of
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course I've always wanted to play very challenging, so yeah, why don't we
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make it harder and play in a young forty killer a forty mile an hour
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wind. I think it was one of your bulls that ended up in our
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boat. God a prosiably you're here. It was at Northwestly, so it
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could have gone your way. But it was brutal out there, absolutely brutal.
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But I actually played quite well despite the conditions. But very good,
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lovely, lovely part of the world. Wow, what a golf course,
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Gosh walked into the locker room and thought, all g I don't belong here.
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This is way too out of my league places too that I feel like.
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That's about Yeah, all right, let's get down to business. We've
2:45
got a bunch of questions from our audience who stick with us regardless of what
2:51
the reality is. But let's go to one of our regulars, and that
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is Rusty from Donnie Brooks. Hey, guys, it's Rusty and donnybrook Well,
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here we are. We're appilion and midwinter and we're having some of the
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coldest mornings I can remember. But I hope you guys are keeping warm and
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you're keeping well. In June, only twenty second of June this year,
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there was an integrated medalicity profile of the Milky Way reashed in Nature Astronomy,
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and one of the findings was that the peak medalicity in our own galaxy is
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it about twenty five thousand lachis from the galactic center. It trails off again
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shortly after getting to our distance, which is twenty six They quote twenty six
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thousand lachies to be very low, about a third of the medalicity of our
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own son By the time we get to the edge of the galaxy at fifty
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thousand nachies. So I'm thinking about the Drake equation, and it would see
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that middle rich locality would be one of the things that complex life like ours
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is indeed of. So it might be a good place to start looking in
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other galaxies, not this particular distance, because I believe it changes from galaxy
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to galaxy. Anyway, what are you thinking? Cheers, thanks for Rusty.
4:28
Yeah, that's a good question. And of course we are looking for
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signs of civil civilizations elsewhere. We're looking close at a home for signs of
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life too. But yeah, I suppose we have talked in the past about
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places that look more likely than others. Has Rusty got a point with the
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metallicity theory, Yeah, and indeed it's well built into, you know,
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the interests of austrobiologists looking for signs of life on other worlds. And so
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just to to you know, give the backstory here, metallicity is it's a
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measure of the extent to which metals are present in the atmosphere of a star,
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and by metals, astronomers mean everything everything other than hydrogen and helium.
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Hydrogen helium metals everything else is. So oxygen is, you know, carbon
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is. It's a different definition from what chemists call metals. So a metal
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for an astronomer is pretty well anything you like. But all of that,
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let's just keep it simple. Yeah, And in many ways there's a good
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reason for that, because hydrogen and helium were formed in the Big Bang,
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so they are primordial. They've been there since the beginning of the universe.
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But the other chemicals haven't. The other elements. They've been formed in the
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atmospheres of stars through many, many generations of stars in our universe, and
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so with each new generation the metallicity is enhanced. You you generate more metals,
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i e. Things other than hydrogen and helium, and when that star
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either explodes or you know, turns into a planetary nebula or whatever at the
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end of its life, it essentially enriches the interstellar medium, that's the very
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very very rarefied gas between the stars. It enriches that with higher metallicity compounds.
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So metallicity is a measure of how much metal there is in a star's
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atmosphere, and normally you do it and indeed this is exactly what's quoted in
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the paper that Rusty referred to. You normally do it by looking at the
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ratio of iron to hydrogen the atmosphere of a star. That's that's termed the
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metal licacy, and it's effectively zero for it kind of calibrated to be zero
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for solar type star stars like the Sun. So things that have got more
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iron in them than the Sun will be said to be metal rich. Things
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that have less iron would be said to be metal poor. And I think
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Rusty's reasoning is correct that it's probably a consequence of the fact that we are
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we are a planet of a metal rich star that gives the Earth all the
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different kind of chemical elements that we need to form life, particularly carbon,
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oxygen, hydrogen, nitrogen in a phosphorus, and those other things that living
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organisms seem to need. So you would naturally look for metal rich stars if
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you are looking for planets that might host life. And so, yeah,
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I think Rust's comments on the money, so in a sense it's you know,
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he's pointed out this Nature Astronomy paper, which indeed shows that the metallicity
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in our galaxy, among stars in our galaxy, and the four hundred billion
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of themselves plenty to choose from but that you can plot a curve that shows
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how that changes with distance from the galactic center. This is exactly what rust
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is talking about, and it peaks more or less at the solar radius where
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we are, and that's very useful because they're the nearest stars to us,
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and those are the ones that are easiest to look for extra planets or to
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look for biomarkers in their exoplanets. We're only just starting to do this by
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analyzing the atmospheres of extra planets, and the James Webb telescope has been success
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for at some level. With that we've found you and I've talked about.
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I think sulfurd outside was the most perhaps exotic compound that's been found by James
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web Space telescope in the atmosphere of an exoplanet. So yeah, that's where
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we're looking. Rusty makes a comment tub we'll be looking at the same radius
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in other galaxies, and I think he's right that the metalistic gradient doesn't or
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the profile doesn't necessarily follow what we have in our own Milky Way galaxy.
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But the problem with those stars in other galaxies is they're very difficult to observe
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because they're a long way away we can, and I think there is one
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example, might be two of an extra galactic in other words, outside our
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own galaxy, exoplanet, in other words, outside our own solar system.
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I think there was one picked up in Andromeda, in the Andromeda galaxy.
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Okay, might be more than that, but it's certainly good news for our
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own galaxy. And very briefly, Rusty mentioned Appelion at the beginning, which
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is the time which the Earth is that it's most distant from the Sun.
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It coincides with I think it's the third of July is usually when it is,
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if I remember rightly, But I always used to feel when I lived
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in Scotland, where in January it's freezing cold and pretty miserable, and yet
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we are nearest to the Sun on the third of January, which tells you
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that the distance of the Earth from the Sun doesn't actually make too much difference
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to the climate. It's all about the tilt of the Earth's axis of the
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season. Well, I think I read the other day that June was one
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was the hottest month on record. Yes, that's for globally. Yeah,
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yeah, we were freezing here. Well that's right, Yes, we we
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are in the upside down part of the planet. So were things like that
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we do? Okay, thanks, I see. I suppose the question would
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be is if we were going to be looking for potential life region in Andromeda,
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we could analyze the stars there and see where the peak point is.
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Yeah, I'm sure that's been done because the stars in are well observed.
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I haven't got a reference to that in my head, but it's an interesting
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thing to look for, so which, yeah, it would be. Yes,
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Okay, thanks Rusty. Good thinking before we move to the next question.
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For those who are not TikTok users, we do a promo every week
11:31
on TikTok before we record the show proper, and we usually end up with
11:37
a dad joke. Unfortunately, it's starting to catch on. This comes from
11:41
Misty West, who's one of our regular listeners and contributors occasionally. Where do
11:46
Bad Rainbows Go? Fred, He's got a good run at solving these Yeah,
11:54
yeah, I'm not sure I'm going to get this. Will do or
11:56
I'll put you out of your misery? Where do bad Rainbow Go? Prism
12:01
It's wait for it. It's a light sentence and gives them time to reflect.
12:07
That's pretty good. I like that very it's very good. Yeah,
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okay, let's move on to our next question, which comes from Russ.
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Guess what it's about. No introduction needed, No introduction, r H.
12:24
Friend Andrew, It's russif from stale Bridge. I love the show's always and
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I have another question about black holes, which I'm sure you're delighted to hear.
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It is related to our universe. Apparently, according to scientific discoveries,
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if you took all the matter in our universe and you compacted it down so
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it creates a black hole, the advent horizon would be larger than the than
12:56
our visible universe. All so there is as we look out into space further
13:03
and further, the space is expanding quicker and quicker. We get to a
13:07
pope where it's apparently exceeds the speed of what the speed of light, which
13:11
would mean that like could not escape. Does this mean that we are living
13:18
inside us? Has been speculated a giant black hole already? Why are your
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views on this? I'd love to know? Thanks a lot. All right,
13:28
Why, let's hope all the black holes in the universe don't decide to
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have a convention soon. If that's the case, yeah, it will be
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dark yeah, it will be very duch. Look, I actually find that
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how to believe the event if you combined all the matter in the universe into
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a black hole, maybe maybe it would maybe the horizon would be comparable in
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size with the universe visible universe. Yeah, yeah, that's right. Yes,
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that well, that's right. That's the that's the tricky bit, because
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the universe may be infinite. That's the really you know, that's the snag
14:13
with all these discussions. But it's been the idea of are we living in
14:20
a black hole? Has really within a black hole event horizon has been around
14:24
for quite a long time. It probably goes back to the likes of Roger
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Penrose back in the maybe in the even in the nineties, eighties and nineties.
14:37
So I've never I've never really um got excited by this idea because I
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think it just adds a complication to something that's already really complicated. And you
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know, in terms of that lie being stopped because where the universe is expanding,
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it faster than the speed of light and things of that, or yes,
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we do know that happens. I don't think you need a black hole
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event horizon too to postulate that. So I'm not. I'm not big on
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the idea of the universe being that that we are within the event horizon,
15:13
the set of massive objects. But I who am I to complain if if
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people, you know, come to the conclusion that that's the case. I
15:22
saw an interesting headline in it was a new scientist. Didn't read the article.
15:30
I just saw the headline as it went past, which was, it's
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the entire universe a quantum object. I think that's what it was, something
15:37
like that. So are we all completely entangled with each other? Well?
15:41
You can take that question on many different levels. Yeah you can, and
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it just makes people's brains hurt, particularly mine. That's about but not not
15:52
likely that we're all, you know, in a I don't like. Look,
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yes, I'd like to sit down and read some of the detailed discussions
16:03
of this, which I have to say I've never done. I've just thought,
16:06
look, that's too hard. It is bad enough to understand what's in
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the universe already without throwing throwing in this idea. I'm not a cosmologist by
16:15
training, although it worked a lot with cosmologists because I've built instruments that provide
16:21
them with the data they need and indeed managed surveys that provide them with the
16:25
data they need. But the stuff that they do with them is quite mind
16:29
blowing. I worked with a cosmologist once because it was his nickname, because
16:34
every time you asked him a question or asked him to explain something, he'd
16:40
say because that's a because modelogist a cors models. Just because the ladyship should
16:55
have saved that for the dad joke. Actually, you know the problem is
16:59
because when we were record, we go out live sometimes that they're coming in
17:02
thick and fast. OVISTI is really thrilled that she achieved her one an only
17:07
chance to stump you, Fred to be foot, I do like I like
17:12
the prison will they do though it's a good one. Okay from black holes
17:18
too? Black holes? Hello Andrew, Fred and Chew in the studio.
17:22
This is pictures here in Auckland, New Zealand. Um. I'm going to
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bring up an old chess nut, which then about black holes. Um,
17:32
and it's something I just can't get my head around. With black holes.
17:36
I get the hole mass of a black hole, like they can calculate the
17:40
mass of a black hole by by the gravitational influence of the surrounding space and
17:45
the size of the event horizon and all that kind of stuff. I get
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that, I think i'd get that. Well, I don't get is when
17:49
they say, yea black holes got no size. But how do they know
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it's got no size? They've already established that the regular laws of physics stand
17:59
apply when they come blake holes, and nothing can escape from a black hole,
18:03
not even lights, so nothing, nothing can escape from their event horizon,
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so it's impossible to image anything from within there. So how do they
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know there's actually got no size? How dow the's not a it's not a
18:17
ball in the middle of the gravity, well the size of a football or
18:21
the size of a golf ball or something like that. And you know,
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how do they know it's got no size at all? That's basically my questian
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they and I hope I don't get even more confused by the answer. But
18:30
thank you very much, thank you, Petras. I think what you'll find
18:34
in a black hole is an object, the shape of a pen as they've
18:38
got to go somewhere. Could be the shape of one sock as well.
18:48
Yes, that's that's a thought, that's a definite thought. Um. But
18:55
when we talk about black holes. We do actually assign sizes to them,
18:59
super mess if black holes, intermediate black holes, etc. So we do
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know that there are various sizes. But I'm thinking he's talking about a different
19:10
element of the black hole theory. Well, yes, so Petrius mentions that
19:15
that they come in different masses, but it's the physical dimensions that's a this
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issue here, and I think I think he's actually right. I think he's
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on the right track because whilst the formal definition of a black hole, at
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least as I was taught, it is a point in space with infinite density.
19:38
That suggests that if it's if it's density is infinite, that it's dimensions
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a zero because it's got mass masses sorry, densities mass over volume. So
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if you have zero volume, doesn't matter what the mass is, it's going
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to have infinite density. So that formal definition. But I have read articles
20:03
and papers which talk about black holes actually having physical dimensions. In other words,
20:12
their density is not quite infinity. It's nearly infinity, but not quite.
20:19
But they still show the properties of black holes. And actually the other
20:23
thing that plays into this is that the black hole properties are varied. It
20:36
in between For example, a rotating black hole, which has quite different characteristics
20:40
from a non rotating black hole. And you can you don't need to look
20:45
very far on the on the web to find numerous accounts of these different things
20:52
rotating black holes. I think they're called K double R black holes. Should
20:57
know all this, shouldn't I. It's a long times for Tello done it.
21:02
There was a point I was going to make. Yeah, that's right.
21:04
There is another aspect of black holes which is called which I like very
21:12
much. It's called a no hair theorem. Beg gave a friend I wrote
21:19
about in one of my books, and I can't remember anything about it.
21:23
No, the no hair theorem says that there are only certain things that you
21:29
can detect about a black hole, and I can't remember what they are,
21:34
like charge and you know, masks and things of that sort. But no,
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I really need to to to revise the no hair theorem. It will
21:44
be very easy because I can't remember which book it's in. I think it's
21:48
in Cosmic Chronicles. I wrote about the no hair theorem to simply because I
21:52
quite like the idea. So what was the answer to the question. I
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think the answers petris Is is right that maybe some black holes do have physical
22:06
dimensions because they're not quite fitting the formal definitions. That's the thing that I
22:14
would look for, and I probably will or go and have a look for
22:17
it, just to check whether I'm talking complete rubbage. But I think I
22:21
do recall reading about black holes which are not infinitesimal in slides. In other
22:30
words, just to type the loose end here, they're not a singularity,
22:33
because that's the point about point with zero dimensions, it's a singularity. Is
22:40
most of them are, but some of them are maybe, or maybe maybe
22:44
most of them are, but some of them are. Yeah, it's a
22:49
great question. All right, Thank you Petris for your question. This is
22:53
Spacens with andrewd Ankley and Professor Fred Watson. Space puts. Okay, Fred,
23:03
we might as well just keep on churning through questions. The next one
23:08
comes from Mikey. Hey, Fred, Hey, Andrew, this is Mikey
23:14
from Illinois. I hope you guys are doing well. And so here's my
23:18
question. When we watch an exo planet passing from another star, say five
23:22
hundred light years away, are we seeing that planet pass in front of its
23:26
star five hundred years ago. I'm assuming the answers, Yes, but this
23:33
popped into my head this morning while making today's coffee, and I just never
23:36
considered it. Can't wait to hear the answers. Guys, thank you so
23:40
much. I absolutely love the show, and thanks for always giving me something
23:44
to chee. It must be desperate monkey, but anyway, I'll appreciate.
23:48
I appreciate it. Uh. And it's funny what pops into ahead when you're
23:52
making coffee. I would suspect the answers yes as well, Fred, because
23:56
everything we see is historical. That's correct, absolutely so. Yeah, the
24:03
planet passing in front of its parent star, that happened five hundred years ago
24:08
and hopefully still happening now, but we don't know. And because absolutely everything
24:15
in the universe, no matter what we observe, we're looking back in time,
24:21
we tend to we there's you know, we tend to ignore the actual
24:30
physicality of what's happening. The fact that in our time frame now that planet
24:37
is still going around its parents star, but we're only seeing it as it
24:41
was five hundred years ago. That has no relevance in astronomy. All we
24:45
can learn about or make any reference to, is what happened at the look
24:51
back time. You know that you're looking back five hundred years, so if
24:56
it's a five hundred light year away star, so yeah, that's that's the
24:59
answer. Um, yeah, it's it's hard to get your head around,
25:02
but you know, you could be looking at a star and it doesn't exist
25:07
anymore because it's so far away. It's it's you know, we're seeing it
25:12
who knows how many thousands of years later, possibly longer, and it might
25:18
as well, you might well have destroyed itself by the time we've seen it,
25:23
but we're seeing it historically. Yes, that's right, and there's no
25:27
way. So what I was trying to say before, it's all about causality
25:32
as well, because causing effect can only take place at the speed of light,
25:36
so there's no you know the fact that's yes. For example, if
25:41
that star five hundred light years away detonated into a supernova, that radiation that
25:48
would come from the supernover hasn't reached the Earth yet, and so from our
25:52
perspective, that star is still there. But eventually we would recognize that no,
25:57
it's not still there because it's is blown up. But it blew up,
26:03
you know, however, many hundred years ago it was, so it's
26:07
it's a slight it is to particularly people coming fresh to astronomy. It's slightly
26:12
odd concept that we're always looking back in time, but we are just one
26:18
nuance to that though. If you've got an extra planet going around a star
26:22
that's five hundred light years away, yes, when when the planets on the
26:29
back side of the star or behind the star, its distance is slightly more
26:33
than it is when it's in front of the star, and that's reflected in
26:37
the light travel talent. So there is a slight correction that you would need
26:41
to make if you're and these corrections are made where people observe these extra planets
26:45
for the different light travel time from when the star planets behind the starter when
26:49
it's in front of the star. In fact, it was that process,
26:55
not with extra planets, but with Jupiter moons that led strong work called Ruber
27:03
in the sixteen seventies, I think to work out what the speed of light
27:07
was in Denmark. That's strong. Thank go all right, thank you,
27:12
Mikey. We will go from Mikey to Michael. Hey, guys, this
27:17
is Michael. I'm from Toronto, Canada. It's my second question to the
27:22
podcast. A feature of science is that new breakthroughs can lead to major revisions
27:29
of our previous last theories. We've seen this time and again over a few
27:33
millennia. Say where we've gone from geocentrism to the now, the discovery of
27:40
the cosmic web and everything in between. Could we be at such a turning
27:45
point now thanks to observations from JWST, having ostensibly found galaxies that are too
27:51
mature to be explained by the Big Bang. What if rather than the Big
27:56
Bang, we had massive supernova population three stars, which are hypothetical and I
28:02
don't think they'd been the third yet. Could this have given us the same
28:07
evidence that we instead credit the Big Bang? Wid Maybe we're engaging in underdetermination
28:15
of theory by data or is there could there be evidence that these galaxies were
28:22
observing from far back our galaxies galaxies of population three stars themselves, But because
28:29
we don't know enough about the way these these stars evolved, it's thrown off
28:33
our models or what the early universe and early galaxies looked like in an earlier
28:40
epoch. Thanks guys, Wow, Marcolet is deep. That's so deep,
28:45
Like you know, I don't think lot's penetrating well. I think Michael's questions
28:52
are great, Well, it is so. Yes, the Gimes Webb telescope
29:00
has shown as galaxies that are more evolved than we would it would expect for
29:07
their age, for the age of the universe as we see it at that
29:11
time. But that doesn't mean that we've got the basic paradigm of the Big
29:17
Bang ron because it's supported by so many other, you know, observations like
29:22
the cosmic microad background radiation, the whole the whole deal suggests that we are
29:29
on the right track with the Big Bang. There are some nuances. We
29:32
get two different values for the for the current expansion of the universe. It's
29:37
what's called a cosmological tension because when you look at the expansion of the universe
29:41
measure as measured today and as measured as measured from galaxies around us today compared
29:49
with what it's what you get by measuring the cosmic microwave background radiation the flash
29:55
of the Big Bang. You get two different answers this, but it's like
30:00
five percent different. So that's that's something that when I started work in astronomy,
30:07
people would have would have been delighted to get an error of five percent
30:11
because the errors were more like one hundred percent back in those days. Anyway,
30:15
I think. I think, however, Michael makes a very good point
30:18
with the idea that possibly we are underestimating things like the influence of population three
30:26
stars, about which we don't know what are their Population three stars are the
30:30
first stars to form in the universe, where all they had was hydrogen and
30:34
helium. None of these metals that we were talking about a few minutes ago
30:38
had come into existence. So they were the first, the first generation of
30:41
stars, and you know, it may be that their influence on galaxy evolution
30:48
is something that needs revised. I don't think we're going to push back the
30:52
date of the Big Bang any further. I think that's pretty well understood thirty
30:56
point eight billion years ago. But our the studying of the earliest galaxies,
31:00
the first galaxies to come into being, is based on therrestical ideas that we
31:07
may well be changing because of new observation. So I think Michael Lake's a
31:11
good point. He does whatever he said. Yeah, Um, I love
31:18
the way people really think about some of the some of the mysteries and things
31:22
that we're trying to unravel in astronomy and space science, including a question without
31:30
notices come in due to our live casting of the recording session. Here it
31:37
is. It's from a meal has a question about how fluids work in the
31:42
human body in space, like stomach fluids and blood and all that sort of
31:47
stuff. What happens in zero G with with all your bodily fluids. Certainly
31:52
know what happens in one G and I don't like it. Yeah, they
31:56
do, that's right. Well, if you know, this is the m
32:00
one of the the key pillars of space medicine. I guess one of the
32:06
things that really people had to struggle with when humans were first going into space.
32:12
So hard does the hard does all the work? You don't have gravity
32:16
to help you, and that means that you need to keep your cardiovascular system
32:22
in really good nick, And that's why they all do a couple of hours
32:25
on a treadmill every day or on a bike or whatever when they're got long
32:30
periods in orbit. So I think it's pretty well understood from a medical perspective,
32:35
just how how these fluids keep on going around? You do want?
32:39
You know? There are aspects I guess that well, you know, like
32:46
the way our digestive processes work. They tend to need help from gravity because
32:52
everything's going downhill. But when you think of many animals, who's who's our
33:00
just processes are taking place horizontally, well it still works, and so that
33:06
would suggest that gravity is not playing that important to role on that. But
33:09
as I said, yes, well understood. Yeah, the fluid in the
33:14
eyes is one of the yes areas. Yeah right, that's right, yes,
33:17
with I pressure and things of that sort. Good stuff. Yeah,
33:23
good question. All right. Another one, this comes from Josh Hey,
33:29
Andrew and Fred. My name's josh from Sydney. I'm a longtime listener,
33:35
first time question ask her. I absolutely loved the show. Thank you both
33:39
so much for producing it putting it online. So my question is about the
33:45
consolation of energy and the red shifting of photons. So so when we look
33:53
at the cosmic microwave background radiation as the universe is expanding, those photons are
34:02
getting red shifted, but that also means that they're losing energy. So so
34:08
where does that lost energy go because it has to be concerted, right,
34:16
Okay, thank you, Joshua. Redshift is starting to become a popular area
34:22
of inquiry. I'm finding we've getting We've been getting a few questions about it
34:28
lately, and it's the you know, probably the pillar of our understanding of
34:34
the wider universe is redshift as well, very important. So Josh is absolutely
34:38
right that a redshift represents a loss of energy. Now I followed up on
34:46
this once, possibly because of an earlier question, or it may have been
34:51
a question on the radio show. I did follow up on that, and
34:54
I think the answer is now it's worse than forty two that the it contributes
35:07
to the overall energy of the universe itself, if I remember rightly reading on
35:13
this, Because because Josh is right, energy is conserved, photons are losing
35:21
energy, and I think, I mean, it's tempting to say, well,
35:28
it contributes to the expansion energy of the universe, but that's a sort
35:32
of circular argument and I don't think it can be that, but I will
35:37
check on it again. I do remember exploring this idea in some depth,
35:40
but it was so long as forgotten the details. So it does go somewhere,
35:45
that's the bottom line. It doesn't go somewhere. It probably goes into
35:49
that cup of coffee that was it. I can't remember who was making it,
35:53
and one of our I think it was Mikey. Mikey, that's right,
35:58
Mikey's cup of coffee. So yes, but but you, But Josh
36:04
is absolutely right that that red shifting is a loss of energy from the light
36:08
or it's changed the energy of the light and it does go somewhere, Okay,
36:14
warms up the universe. That could be the bottom line. Once again,
36:17
we demonstrate our pros for giving you adequate answers. I don't think that's
36:22
anything like adequate. I'm embarrassed to be here. I think most most of
36:28
our listeners know more than we do. Yes, and then they ask us
36:30
questions about it. I think that that might be the whole thing. You
36:36
know, he is a conspiracy theory that the whole reason why space Nuts is
36:39
there is to make our listeners feel more intelligent, feel more intelligent because they
36:46
are. Yeah, it's working all right, Thanks Josh. This is space
36:52
Nuts sort of with Andrew Dankley and Professor Fred Watson space Nets Like I will
37:04
cram a few more questions in before we wrap it up. The next one
37:07
comes from DJI. This is DJ from Indianapolis, Indiana in the United States.
37:16
My question is about time dilation. I've heard it said that one way
37:22
that you would be able to see the dilation would be spaceship is traveling past
37:28
Earth, and you can see into it like through a window, and you
37:30
would see that clock and the spaceship they're traveling close to the speed of light.
37:34
You would actually see it ticks slowly in yours. Since our second is
37:39
no longer determined by the speed of the Earth but by the ssium adam electron
37:45
spin, does that change as well? So if you're in the spaceship going
37:49
the speed of light and that sasium adam electron spin is nine billion whatever times
37:58
a second, does it now been four billion times a second or two billion
38:08
times a second if you're going close to the speed of light or does it
38:15
not know the difference? Hopefully that was clear enough to get him answered.
38:25
I really enjoy the show. Thanks guys, and welcome to our world.
38:30
DJA. It is so Yeah, you might want to explain what he means
38:37
by the way, we've changed the definition of a second. Yeah, so
38:42
a seconds defined in atomic atomic frequencies. It's it's gone from you know.
38:51
You know, we've known for many years and the Earth is a pretty poor
38:54
time keeper in terms of its rotation because the rotation changes. So if you're
39:00
going to define a second as being one three thousand, six hundreds of an
39:04
hour and an hour as one twenty fourth of our evolution of the Earth,
39:07
then it's it's going to change over time. So it's been defined in terms
39:14
of I'm not sure whether it's still defined in terms of vibrations of a caesium
39:20
atom, but it certainly used to be. But that here's the thing though,
39:27
in terms of the relativistic time dilation, that as far as the caesium
39:34
clock in your in the spacecraft is concerned, it's still vibrating at the same
39:37
rate. It's that an observer who's in a different reference frame sees it basically
39:46
vibrating slower. And that's how it would look if you could see the vibrations
39:52
of a caesium atom in a passing spacecraft, they would look to be slower
39:57
because because time is taking place more slowly apparently, But for the for the
40:04
people in the spacecraft, it's still the sagothic change. We talked about this
40:07
last week with someone questioning the gravitational effect of a black hole with people on
40:13
a planet. In the movie Into Stellar, how they portrayed data seven you
40:15
know, seven years pass for every hour, which was an extreme example.
40:20
But also you know, if we were in a different place in the galaxy
40:27
and we could observe people in another part of the galaxy, they would either
40:31
look like they're moving faster like an ant hill or slower, depending on which
40:36
part of the galaxy you were in and the time dilation effect. Yeah,
40:40
right, if you could absorb, observe, Yeah, if you're if you're
40:45
in a you're this is we're now talking about gravitational time dilation, yes,
40:51
rather than the velocity time dilation, which is what DJ was. Look the
40:55
two fates. I always got those two mixed up. Wells, shame on
41:00
you, Andrew. So so yeah, the issue is that it's it's always
41:09
about reference frames. It's about how you see, you know, how you
41:14
a world reference frame sees somebody else and other things going on in a different
41:20
reference frame. So that yes, if you were at a different point in
41:23
the gravitational well you would you would see talent progressing at the different speed,
41:29
and it would depend on where you were in the gravitational well as whether that
41:31
was faster or slower. Exactly as you've said, perfect, All right,
41:35
thanks JJ. The next question comes from Colin. Hi. This is Carlin
41:40
from Aballene, Texas. And in your last episode you had the researchers say
41:50
they calculated the trajectory of the comment or asteroid that was outside our solar system.
41:58
But couldn't it just as easily come shrug the orc cloud because it surrounds
42:04
us here. Thank you, Thank you, Colin, We do too,
42:13
Thanks Colin. Um. I think we can dismiss the aort cloud theory because
42:17
of the speed of these particular things. See, you don't leave me,
42:22
you don't need me, and you don't I'm just remembering what you taught me,
42:25
Fred. Yeah, that's right. So um Or cloud comets come in
42:32
at certain velocities. I can't remember what the maximum is for a cloud commet,
42:39
but I've read wait for it you you ought to know? Oh well
42:46
that was a good one. Yeah, that's so good one. I like
42:50
that one. You ought to take notice of the blocked cloud. Yes,
42:55
anyway, Yeah, Orts was a very very competent astronomer who did a fantastic
43:02
amount of interesting science in the early post war years. Perst second, anyway,
43:09
that's all about so work. Cloud comets coming from the old cloud at
43:15
velocity x, but something interstellar would come in at two x or x plus
43:22
fifty kilometers per second or something like that. They're they're much faster, So
43:24
that that's the that's a critical difference between you know, an exo asteroid perhaps,
43:31
or or or a comet asteroid of body that's come out from the old
43:37
cloud. So it's all about it's a matter of degree. Yeah, if
43:43
if an exo asteroid just happened to impact something in the or cloud and send
43:47
it hurdling our way, you'd still know the difference, wouldn't you. Yeah,
43:53
you, um, you probably would actually because you know, I mean
44:00
this is along the lines of the theory of that object that we're talking about
44:02
last week, that it may have been disturbed by Planet Night, had they
44:07
gravitational tugged by Planet Night. Yeah, but it's still coming in at an
44:12
excess velocity. That's correct. All right, very good, Thank you,
44:17
Colin. Lovely to hear from you. And we've got our final question for
44:22
this week from Andreas. Hi Andreas from Sweden here and thanks for a great
44:30
podcast. So I have a question I would like to get your input on
44:36
as you can, as we can, all field, the world is kind
44:37
of moving in our direction having two major bay power blocks, Like on the
44:43
one side we have the US and Europe and on the other side we have
44:45
China Russia. So which kind of breaks back the feeling of the old space
44:50
range in the US and sub which propels things forward and about. But if
44:55
we look from the perspective of humanity, do you believe having these two competing
45:00
blocks, it's better? And if we all came together, it's like one
45:05
happy space family reaching the stars together. So what do you think is better
45:09
for a scientific progress and expiration? Is it collaboration or competition? Altima,
45:17
great question, Andrea so well. As a matter of fact, he's forgotten
45:22
North Korea. I just finished watching season three for All Mankind and they were
45:27
the first to step on Mars. Oh okay, so I hope that wasn't
45:31
a spoiler for anybody. Good growth. Sorry, block here is too late.
45:37
Yeah, the space race has changed. It used to be the US
45:39
and Russia and or the Soviet Union, and now it's the USA, Europe
45:46
and Russia and China. Although they do tend to work independently, they do
45:52
collaborate. But what we are seeing is that we've got collaboration from just about
45:57
all on Sundry, maybe to a lesser degree each China, but they're not
46:00
completely blocking everybody out, and one would hope, and we do see this
46:07
a lot in astronomy and space science, is that they do share data,
46:09
they do share information, they do share resources, they work together. So
46:15
I from my perspective, I think it's good the way things are going at
46:20
the moment. What worries me is that someone will get somewhere or find something
46:24
and say, well, we we're not going to share that. We're going
46:29
to mind the hell out of it and keep it for ourselves. Um.
46:32
I don't know, it's it's a I'd rather be a cooperative venture than one
46:39
of conflict, although conflict has also proven to be the mother of invention in
46:44
history, in the history of humanity. So cut oath ways, as far
46:49
as I think that's andreasis points, isn't it that soon? You know,
46:52
we we gained enormously in the nineteen sixties by that geopolitical competition between the Soviet
47:04
Yes and the Western Bloc, in particular between Soviet Union and NASA SOU.
47:13
But I do think, you know, you've got to kind of bring together.
47:22
There are a number of ways of looking at this, maybe space can
47:27
be a beneficial thing in terms of international relations rather than in terms of technological
47:32
development. So you're still seeing, i suppose, the last vestiges of that
47:38
with the International Space Station, which still has Russian and American astronauts and cosmonauts
47:45
basically collaborating in a fantastic way. And so space diplomacy I think still has
47:55
a place in the the world's future, and I've often wondered whether, yes,
48:05
there's there's certainly competition at the moment, and a lot of that is
48:10
is to do with the rise of China, the fact that you have a
48:14
nation here that wants to assert itself as a as a world player on a
48:17
world stage, with a different political system from what the Western world has,
48:23
and that's that is perhaps one of the reasons why we're seeing such really capable
48:30
and quite notable achievements from the China China National Space Agency Administration SAM. I
48:40
think perhaps looking further into the future, when we're talking about flights to Mars
48:50
human exploration of Mars, I suspect that will turn out to be so expensive
48:58
that the only way we'll really make it work effectively would be to have international
49:05
cooperation, and it may well be that we might see a new era of
49:09
warm and fuzzy international corporation, perhaps comparable with what we saw around the time
49:16
of the end of the Cold War. When that would say, though,
49:21
the war in Ukraine did lead to space tensions between the US and Russia,
49:28
but it was something that was happening on Earth that caused that. Yeah,
49:31
and I'm pretty sure the people that were in space at the time really didn't
49:36
want to have a bar of it, but they were following orders. Yes,
49:39
that's right. I can't rememb whether or mentioned that when I was at
49:45
the Committee on the Peaceful Uses of Outer Space that meeting in February, that
49:51
those geopolitical tensions were very, very evident in some of the comments that were
49:55
being made by delegates of certain nations, and it was all about the war
50:01
in Ukraine. So there is so when you've got something like that going on,
50:07
then it really clouds the issue. But all credit to astronauts cosmonauts for
50:15
sticking together up there in the International Space Station and to their respective space agencies
50:20
for actually negotiating diplomatically. Ross Cosmos had a Buyer brand head who has now
50:30
been removed. He's now in Ukraine. Actually this Dimitri R. Godson was
50:36
that his name? Yeah, that sounds about right. Yeah, yeah,
50:38
he's so. And we've had far kind of fewer belligerent signals from ros Cosmos
50:47
since then, although you know, the internal politics might be the saying,
50:52
but we've got you know, still in the space station itself. It is
50:57
business as usual, which is quite a quite extraordinary, quite extra it is.
51:01
It is, it seems in terms of space exploration and even being close
51:09
to home orbiting in the International Space Station, they tend to leave the politics
51:14
to the politicians and up there, away from it all, it's a it's
51:19
a different world and they all get along most famously much of the time,
51:23
as far as we're aware. And yeah, and I hope it stays that
51:28
way. And yeah, I hope you're right about the future of exploration to
51:34
Mars. Maybe maybe it will require international cooperation and to make it, to
51:38
make it happen, bring everybody together. I think that would be a great
51:42
thing. Thank you so much. Andrea's a fantastic question. We don't usually
51:47
get into politics, but that was that was a good one. That brings
51:53
us to the end of the show. Of course, if you do have
51:54
questions for us, you can send them through our website. The AMA table
51:59
or the send us you or Voice message tab is the way to go.
52:01
You can send us text questions as well. Don't forget to tell us who
52:06
you are and where you're from, and peruse the Space Nuts shop while you're
52:09
there. There's nothing worth buying, but do you do it anyway. Thank
52:14
you. As always, Fred has been a great pleasure. Great to spend
52:16
some time helping people understand space and everything, and although half the time they
52:22
help us understand a bit more too, so good Thank you, Fred,
52:28
pleasure I was always Andrew look forward to speaking next week. We will.
52:31
And thanks to Hugh in the studio for sending messages through from our live audience
52:37
when we while we were according today, oh my gosh, I said something
52:40
nice about Hugh that won't happen again. And from me Andrew, don't clear
52:44
you. Thanks for your company on this edition of Space Nuts. Catch you
52:46
on the next episode. Bye bye. You'll be listening to this Space Nuts
52:52
podcast available at Apple Podcasts, Google Podcasts, Spotify, iHeart Radio, or
53:00
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