#360: Collaboration vs. Competition: Advancing Space Exploration Together & Other Space Questions

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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

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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

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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

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two Space Nuts as an actual board
it deal good. Yes, And joining

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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

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might be alien kind as well.
It could be Yeah, it's all sorts

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of possibilities, indeed, But yes, how have you beaten? Or not

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so bad? Thank you? My
nearest and dearest has got the most awful

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cold, so I expected them to
be soon. So yeah, who knows

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what I'll be what stays I'll be
in next time we speak? Yes,

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well, fingers crossed that you managed
to avoid it. My dad's got at

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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,

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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

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got a bunch of questions from our
audience who stick with us regardless of what

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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.

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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

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on TikTok before we record the show
proper, and we usually end up with

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a dad joke. Unfortunately, it's
starting to catch on. This comes from

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Misty West, who's one of our
regular listeners and contributors occasionally. Where do

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Bad Rainbows Go? Fred, He's
got a good run at solving these Yeah,

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yeah, I'm not sure I'm going
to get this. Will do or

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I'll put you out of your misery? Where do bad Rainbow Go? Prism

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It's wait for it. It's a
light sentence and gives them time to reflect.

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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.

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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

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our visible universe. All so there
is as we look out into space further

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and further, the space is expanding
quicker and quicker. We get to a

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pope where it's apparently exceeds the speed
of what the speed of light, which

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would mean that like could not escape. Does this mean that we are living

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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,

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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

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with all these discussions. But it's
been the idea of are we living in

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a black hole? Has really within
a black hole event horizon has been around

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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.

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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,

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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

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saw an interesting headline in it was
a new scientist. Didn't read the article.

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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

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like that. So are we all
completely entangled with each other? Well?

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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

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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

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of this, which I have to
say I've never done. I've just thought,

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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

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training, although it worked a lot
with cosmologists because I've built instruments that provide

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them with the data they need and
indeed managed surveys that provide them with the

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data they need. But the stuff
that they do with them is quite mind

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blowing. I worked with a cosmologist
once because it was his nickname, because

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every time you asked him a question
or asked him to explain something, he'd

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say because that's a because modelogist a
cors models. Just because the ladyship should

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have saved that for the dad joke. Actually, you know the problem is

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because when we were record, we
go out live sometimes that they're coming in

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thick and fast. OVISTI is really
thrilled that she achieved her one an only

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chance to stump you, Fred to
be foot, I do like I like

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the prison will they do though it's
a good one. Okay from black holes

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too? Black holes? Hello Andrew, Fred and Chew in the studio.

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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,

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and it's something I just can't get
my head around. With black holes.

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I get the hole mass of a
black hole, like they can calculate the

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mass of a black hole by by
the gravitational influence of the surrounding space and

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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

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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

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apply when they come blake holes,
and nothing can escape from a black hole,

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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

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ball in the middle of the gravity, well the size of a football or

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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

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thank you very much, thank you, Petras. I think what you'll find

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in a black hole is an object, the shape of a pen as they've

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got to go somewhere. Could be
the shape of one sock as well.

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Yes, that's that's a thought,
that's a definite thought. Um. But

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when we talk about black holes.
We do actually assign sizes to them,

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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

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element of the black hole theory.
Well, yes, so Petrius mentions that

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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.

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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

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and papers which talk about black holes
actually having physical dimensions. In other words,

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their density is not quite infinity.
It's nearly infinity, but not quite.

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But they still show the properties of
black holes. And actually the other

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thing that plays into this is that
the black hole properties are varied. It

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in between For example, a rotating
black hole, which has quite different characteristics

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from a non rotating black hole.
And you can you don't need to look

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very far on the on the web
to find numerous accounts of these different things

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rotating black holes. I think they're
called K double R black holes. Should

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know all this, shouldn't I.
It's a long times for Tello done it.

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There was a point I was going
to make. Yeah, that's right.

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There is another aspect of black holes
which is called which I like very

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much. It's called a no hair
theorem. Beg gave a friend I wrote

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about in one of my books,
and I can't remember anything about it.

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No, the no hair theorem says
that there are only certain things that you

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can detect about a black hole,
and I can't remember what they are,

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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

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be very easy because I can't remember
which book it's in. I think it's

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in Cosmic Chronicles. I wrote about
the no hair theorem to simply because I

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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

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dimensions because they're not quite fitting the
formal definitions. That's the thing that I

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would look for, and I probably
will or go and have a look for

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it, just to check whether I'm
talking complete rubbage. But I think I

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do recall reading about black holes which
are not infinitesimal in slides. In other

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words, just to type the loose
end here, they're not a singularity,

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because that's the point about point with
zero dimensions, it's a singularity. Is

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most of them are, but some
of them are maybe, or maybe maybe

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most of them are, but some
of them are. Yeah, it's a

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great question. All right, Thank
you Petris for your question. This is

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Spacens with andrewd Ankley and Professor Fred
Watson. Space puts. Okay, Fred,

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we might as well just keep on
churning through questions. The next one

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comes from Mikey. Hey, Fred, Hey, Andrew, this is Mikey

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from Illinois. I hope you guys
are doing well. And so here's my

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question. When we watch an exo
planet passing from another star, say five

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hundred light years away, are we
seeing that planet pass in front of its

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star five hundred years ago. I'm
assuming the answers, Yes, but this

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popped into my head this morning while
making today's coffee, and I just never

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considered it. Can't wait to hear
the answers. Guys, thank you so

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much. I absolutely love the show, and thanks for always giving me something

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to chee. It must be desperate
monkey, but anyway, I'll appreciate.

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I appreciate it. Uh. And
it's funny what pops into ahead when you're

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making coffee. I would suspect the
answers yes as well, Fred, because

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everything we see is historical. That's
correct, absolutely so. Yeah, the

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planet passing in front of its parent
star, that happened five hundred years ago

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and hopefully still happening now, but
we don't know. And because absolutely everything

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in the universe, no matter what
we observe, we're looking back in time,

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we tend to we there's you know, we tend to ignore the actual

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physicality of what's happening. The fact
that in our time frame now that planet

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is still going around its parents star, but we're only seeing it as it

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was five hundred years ago. That
has no relevance in astronomy. All we

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can learn about or make any reference
to, is what happened at the look

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back time. You know that you're
looking back five hundred years, so if

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it's a five hundred light year away
star, so yeah, that's that's the

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answer. Um, yeah, it's
it's hard to get your head around,

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but you know, you could be
looking at a star and it doesn't exist

285
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anymore because it's so far away.
It's it's you know, we're seeing it

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who knows how many thousands of years
later, possibly longer, and it might

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as well, you might well have
destroyed itself by the time we've seen it,

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but we're seeing it historically. Yes, that's right, and there's no

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way. So what I was trying
to say before, it's all about causality

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as well, because causing effect can
only take place at the speed of light,

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so there's no you know the fact
that's yes. For example, if

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that star five hundred light years away
detonated into a supernova, that radiation that

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would come from the supernover hasn't reached
the Earth yet, and so from our

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perspective, that star is still there. But eventually we would recognize that no,

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it's not still there because it's is
blown up. But it blew up,

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you know, however, many hundred
years ago it was, so it's

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it's a slight it is to particularly
people coming fresh to astronomy. It's slightly

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odd concept that we're always looking back
in time, but we are just one

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nuance to that though. If you've
got an extra planet going around a star

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that's five hundred light years away,
yes, when when the planets on the

301
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back side of the star or behind
the star, its distance is slightly more

302
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than it is when it's in front
of the star, and that's reflected in

303
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the light travel talent. So there
is a slight correction that you would need

304
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to make if you're and these corrections
are made where people observe these extra planets

305
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for the different light travel time from
when the star planets behind the starter when

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it's in front of the star.
In fact, it was that process,

307
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not with extra planets, but with
Jupiter moons that led strong work called Ruber

308
00:27:03.480 --> 00:27:06.960
in the sixteen seventies, I think
to work out what the speed of light

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was in Denmark. That's strong.
Thank go all right, thank you,

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Mikey. We will go from Mikey
to Michael. Hey, guys, this

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00:27:17.680 --> 00:27:22.799
is Michael. I'm from Toronto,
Canada. It's my second question to the

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00:27:22.839 --> 00:27:29.880
podcast. A feature of science is
that new breakthroughs can lead to major revisions

313
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of our previous last theories. We've
seen this time and again over a few

314
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millennia. Say where we've gone from
geocentrism to the now, the discovery of

315
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the cosmic web and everything in between. Could we be at such a turning

316
00:27:45.319 --> 00:27:51.079
point now thanks to observations from JWST, having ostensibly found galaxies that are too

317
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mature to be explained by the Big
Bang. What if rather than the Big

318
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Bang, we had massive supernova population
three stars, which are hypothetical and I

319
00:28:02.440 --> 00:28:07.160
don't think they'd been the third yet. Could this have given us the same

320
00:28:07.279 --> 00:28:15.119
evidence that we instead credit the Big
Bang? Wid Maybe we're engaging in underdetermination

321
00:28:15.160 --> 00:28:22.119
of theory by data or is there
could there be evidence that these galaxies were

322
00:28:22.119 --> 00:28:29.200
observing from far back our galaxies galaxies
of population three stars themselves, But because

323
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we don't know enough about the way
these these stars evolved, it's thrown off

324
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our models or what the early universe
and early galaxies looked like in an earlier

325
00:28:40.640 --> 00:28:45.839
epoch. Thanks guys, Wow,
Marcolet is deep. That's so deep,

326
00:28:45.960 --> 00:28:52.480
Like you know, I don't think
lot's penetrating well. I think Michael's questions

327
00:28:52.480 --> 00:29:00.440
are great, Well, it is
so. Yes, the Gimes Webb telescope

328
00:29:00.519 --> 00:29:07.920
has shown as galaxies that are more
evolved than we would it would expect for

329
00:29:07.200 --> 00:29:11.240
their age, for the age of
the universe as we see it at that

330
00:29:11.359 --> 00:29:17.960
time. But that doesn't mean that
we've got the basic paradigm of the Big

331
00:29:17.960 --> 00:29:22.720
Bang ron because it's supported by so
many other, you know, observations like

332
00:29:22.920 --> 00:29:29.000
the cosmic microad background radiation, the
whole the whole deal suggests that we are

333
00:29:29.640 --> 00:29:32.079
on the right track with the Big
Bang. There are some nuances. We

334
00:29:32.160 --> 00:29:37.400
get two different values for the for
the current expansion of the universe. It's

335
00:29:37.400 --> 00:29:41.039
what's called a cosmological tension because when
you look at the expansion of the universe

336
00:29:41.400 --> 00:29:49.200
measure as measured today and as measured
as measured from galaxies around us today compared

337
00:29:49.240 --> 00:29:55.880
with what it's what you get by
measuring the cosmic microwave background radiation the flash

338
00:29:55.880 --> 00:30:00.319
of the Big Bang. You get
two different answers this, but it's like

339
00:30:00.839 --> 00:30:06.759
five percent different. So that's that's
something that when I started work in astronomy,

340
00:30:07.119 --> 00:30:10.759
people would have would have been delighted
to get an error of five percent

341
00:30:11.519 --> 00:30:15.000
because the errors were more like one
hundred percent back in those days. Anyway,

342
00:30:15.319 --> 00:30:18.880
I think. I think, however, Michael makes a very good point

343
00:30:18.920 --> 00:30:26.880
with the idea that possibly we are
underestimating things like the influence of population three

344
00:30:26.920 --> 00:30:30.039
stars, about which we don't know
what are their Population three stars are the

345
00:30:30.079 --> 00:30:34.119
first stars to form in the universe, where all they had was hydrogen and

346
00:30:34.200 --> 00:30:38.200
helium. None of these metals that
we were talking about a few minutes ago

347
00:30:38.319 --> 00:30:41.480
had come into existence. So they
were the first, the first generation of

348
00:30:41.559 --> 00:30:48.559
stars, and you know, it
may be that their influence on galaxy evolution

349
00:30:48.039 --> 00:30:52.480
is something that needs revised. I
don't think we're going to push back the

350
00:30:52.559 --> 00:30:56.599
date of the Big Bang any further. I think that's pretty well understood thirty

351
00:30:56.599 --> 00:31:00.839
point eight billion years ago. But
our the studying of the earliest galaxies,

352
00:31:00.880 --> 00:31:07.319
the first galaxies to come into being, is based on therrestical ideas that we

353
00:31:07.160 --> 00:31:11.279
may well be changing because of new
observation. So I think Michael Lake's a

354
00:31:11.279 --> 00:31:18.799
good point. He does whatever he
said. Yeah, Um, I love

355
00:31:18.839 --> 00:31:22.440
the way people really think about some
of the some of the mysteries and things

356
00:31:22.480 --> 00:31:30.039
that we're trying to unravel in astronomy
and space science, including a question without

357
00:31:30.160 --> 00:31:37.799
notices come in due to our live
casting of the recording session. Here it

358
00:31:37.880 --> 00:31:42.519
is. It's from a meal has
a question about how fluids work in the

359
00:31:42.599 --> 00:31:47.279
human body in space, like stomach
fluids and blood and all that sort of

360
00:31:47.279 --> 00:31:52.119
stuff. What happens in zero G
with with all your bodily fluids. Certainly

361
00:31:52.119 --> 00:31:56.359
know what happens in one G and
I don't like it. Yeah, they

362
00:31:56.400 --> 00:32:00.279
do, that's right. Well,
if you know, this is the m

363
00:32:00.759 --> 00:32:06.799
one of the the key pillars of
space medicine. I guess one of the

364
00:32:06.839 --> 00:32:12.279
things that really people had to struggle
with when humans were first going into space.

365
00:32:12.519 --> 00:32:15.960
So hard does the hard does all
the work? You don't have gravity

366
00:32:16.039 --> 00:32:22.359
to help you, and that means
that you need to keep your cardiovascular system

367
00:32:22.400 --> 00:32:25.480
in really good nick, And that's
why they all do a couple of hours

368
00:32:25.480 --> 00:32:30.119
on a treadmill every day or on
a bike or whatever when they're got long

369
00:32:30.240 --> 00:32:35.680
periods in orbit. So I think
it's pretty well understood from a medical perspective,

370
00:32:35.799 --> 00:32:39.440
just how how these fluids keep on
going around? You do want?

371
00:32:39.640 --> 00:32:46.799
You know? There are aspects I
guess that well, you know, like

372
00:32:46.960 --> 00:32:52.440
the way our digestive processes work.
They tend to need help from gravity because

373
00:32:52.440 --> 00:33:00.119
everything's going downhill. But when you
think of many animals, who's who's our

374
00:33:00.200 --> 00:33:06.079
just processes are taking place horizontally,
well it still works, and so that

375
00:33:06.400 --> 00:33:08.960
would suggest that gravity is not playing
that important to role on that. But

376
00:33:09.160 --> 00:33:14.240
as I said, yes, well
understood. Yeah, the fluid in the

377
00:33:14.319 --> 00:33:17.640
eyes is one of the yes areas. Yeah right, that's right, yes,

378
00:33:17.839 --> 00:33:23.240
with I pressure and things of that
sort. Good stuff. Yeah,

379
00:33:23.279 --> 00:33:29.519
good question. All right. Another
one, this comes from Josh Hey,

380
00:33:29.599 --> 00:33:34.720
Andrew and Fred. My name's josh
from Sydney. I'm a longtime listener,

381
00:33:35.000 --> 00:33:39.000
first time question ask her. I
absolutely loved the show. Thank you both

382
00:33:39.359 --> 00:33:45.759
so much for producing it putting it
online. So my question is about the

383
00:33:45.839 --> 00:33:53.160
consolation of energy and the red shifting
of photons. So so when we look

384
00:33:53.160 --> 00:34:02.440
at the cosmic microwave background radiation as
the universe is expanding, those photons are

385
00:34:02.480 --> 00:34:08.840
getting red shifted, but that also
means that they're losing energy. So so

386
00:34:08.960 --> 00:34:15.000
where does that lost energy go because
it has to be concerted, right,

387
00:34:16.599 --> 00:34:22.679
Okay, thank you, Joshua.
Redshift is starting to become a popular area

388
00:34:22.800 --> 00:34:28.199
of inquiry. I'm finding we've getting
We've been getting a few questions about it

389
00:34:28.280 --> 00:34:34.199
lately, and it's the you know, probably the pillar of our understanding of

390
00:34:34.239 --> 00:34:38.639
the wider universe is redshift as well, very important. So Josh is absolutely

391
00:34:38.719 --> 00:34:46.119
right that a redshift represents a loss
of energy. Now I followed up on

392
00:34:46.199 --> 00:34:51.239
this once, possibly because of an
earlier question, or it may have been

393
00:34:51.280 --> 00:34:53.960
a question on the radio show.
I did follow up on that, and

394
00:34:54.000 --> 00:35:07.639
I think the answer is now it's
worse than forty two that the it contributes

395
00:35:07.719 --> 00:35:13.519
to the overall energy of the universe
itself, if I remember rightly reading on

396
00:35:13.599 --> 00:35:20.880
this, Because because Josh is right, energy is conserved, photons are losing

397
00:35:21.000 --> 00:35:28.719
energy, and I think, I
mean, it's tempting to say, well,

398
00:35:28.719 --> 00:35:32.119
it contributes to the expansion energy of
the universe, but that's a sort

399
00:35:32.119 --> 00:35:37.159
of circular argument and I don't think
it can be that, but I will

400
00:35:37.239 --> 00:35:40.639
check on it again. I do
remember exploring this idea in some depth,

401
00:35:40.719 --> 00:35:45.360
but it was so long as forgotten
the details. So it does go somewhere,

402
00:35:45.400 --> 00:35:49.000
that's the bottom line. It doesn't
go somewhere. It probably goes into

403
00:35:49.039 --> 00:35:52.800
that cup of coffee that was it. I can't remember who was making it,

404
00:35:53.159 --> 00:35:58.079
and one of our I think it
was Mikey. Mikey, that's right,

405
00:35:58.159 --> 00:36:04.159
Mikey's cup of coffee. So yes, but but you, But Josh

406
00:36:04.199 --> 00:36:08.519
is absolutely right that that red shifting
is a loss of energy from the light

407
00:36:08.679 --> 00:36:14.079
or it's changed the energy of the
light and it does go somewhere, Okay,

408
00:36:14.239 --> 00:36:16.920
warms up the universe. That could
be the bottom line. Once again,

409
00:36:17.000 --> 00:36:22.239
we demonstrate our pros for giving you
adequate answers. I don't think that's

410
00:36:22.320 --> 00:36:28.000
anything like adequate. I'm embarrassed to
be here. I think most most of

411
00:36:28.000 --> 00:36:30.519
our listeners know more than we do. Yes, and then they ask us

412
00:36:30.599 --> 00:36:36.320
questions about it. I think that
that might be the whole thing. You

413
00:36:36.360 --> 00:36:39.400
know, he is a conspiracy theory
that the whole reason why space Nuts is

414
00:36:39.440 --> 00:36:46.119
there is to make our listeners feel
more intelligent, feel more intelligent because they

415
00:36:46.159 --> 00:36:52.119
are. Yeah, it's working all
right, Thanks Josh. This is space

416
00:36:52.239 --> 00:37:04.360
Nuts sort of with Andrew Dankley and
Professor Fred Watson space Nets Like I will

417
00:37:04.360 --> 00:37:07.000
cram a few more questions in before
we wrap it up. The next one

418
00:37:07.079 --> 00:37:15.760
comes from DJI. This is DJ
from Indianapolis, Indiana in the United States.

419
00:37:16.159 --> 00:37:22.519
My question is about time dilation.
I've heard it said that one way

420
00:37:22.559 --> 00:37:28.079
that you would be able to see
the dilation would be spaceship is traveling past

421
00:37:28.199 --> 00:37:30.880
Earth, and you can see into
it like through a window, and you

422
00:37:30.880 --> 00:37:34.679
would see that clock and the spaceship
they're traveling close to the speed of light.

423
00:37:34.920 --> 00:37:39.400
You would actually see it ticks slowly
in yours. Since our second is

424
00:37:39.480 --> 00:37:44.960
no longer determined by the speed of
the Earth but by the ssium adam electron

425
00:37:45.039 --> 00:37:49.400
spin, does that change as well? So if you're in the spaceship going

426
00:37:49.440 --> 00:37:58.880
the speed of light and that sasium
adam electron spin is nine billion whatever times

427
00:37:58.880 --> 00:38:08.280
a second, does it now been
four billion times a second or two billion

428
00:38:08.320 --> 00:38:15.119
times a second if you're going close
to the speed of light or does it

429
00:38:15.639 --> 00:38:24.679
not know the difference? Hopefully that
was clear enough to get him answered.

430
00:38:25.880 --> 00:38:30.360
I really enjoy the show. Thanks
guys, and welcome to our world.

431
00:38:30.440 --> 00:38:37.679
DJA. It is so Yeah,
you might want to explain what he means

432
00:38:37.719 --> 00:38:40.880
by the way, we've changed the
definition of a second. Yeah, so

433
00:38:42.119 --> 00:38:51.760
a seconds defined in atomic atomic frequencies. It's it's gone from you know.

434
00:38:51.800 --> 00:38:54.039
You know, we've known for many
years and the Earth is a pretty poor

435
00:38:54.079 --> 00:39:00.440
time keeper in terms of its rotation
because the rotation changes. So if you're

436
00:39:00.440 --> 00:39:04.760
going to define a second as being
one three thousand, six hundreds of an

437
00:39:04.760 --> 00:39:07.119
hour and an hour as one twenty
fourth of our evolution of the Earth,

438
00:39:07.840 --> 00:39:14.320
then it's it's going to change over
time. So it's been defined in terms

439
00:39:14.400 --> 00:39:20.920
of I'm not sure whether it's still
defined in terms of vibrations of a caesium

440
00:39:20.920 --> 00:39:25.480
atom, but it certainly used to
be. But that here's the thing though,

441
00:39:27.159 --> 00:39:34.239
in terms of the relativistic time dilation, that as far as the caesium

442
00:39:34.280 --> 00:39:37.840
clock in your in the spacecraft is
concerned, it's still vibrating at the same

443
00:39:37.920 --> 00:39:46.039
rate. It's that an observer who's
in a different reference frame sees it basically

444
00:39:46.119 --> 00:39:52.400
vibrating slower. And that's how it
would look if you could see the vibrations

445
00:39:52.400 --> 00:39:57.320
of a caesium atom in a passing
spacecraft, they would look to be slower

446
00:39:57.360 --> 00:40:04.239
because because time is taking place more
slowly apparently, But for the for the

447
00:40:04.239 --> 00:40:07.039
people in the spacecraft, it's still
the sagothic change. We talked about this

448
00:40:07.159 --> 00:40:13.159
last week with someone questioning the gravitational
effect of a black hole with people on

449
00:40:13.199 --> 00:40:15.400
a planet. In the movie Into
Stellar, how they portrayed data seven you

450
00:40:15.440 --> 00:40:20.559
know, seven years pass for every
hour, which was an extreme example.

451
00:40:20.840 --> 00:40:27.280
But also you know, if we
were in a different place in the galaxy

452
00:40:27.920 --> 00:40:30.960
and we could observe people in another
part of the galaxy, they would either

453
00:40:31.000 --> 00:40:36.320
look like they're moving faster like an
ant hill or slower, depending on which

454
00:40:36.320 --> 00:40:39.840
part of the galaxy you were in
and the time dilation effect. Yeah,

455
00:40:40.039 --> 00:40:45.519
right, if you could absorb,
observe, Yeah, if you're if you're

456
00:40:45.519 --> 00:40:50.400
in a you're this is we're now
talking about gravitational time dilation, yes,

457
00:40:51.280 --> 00:40:55.360
rather than the velocity time dilation,
which is what DJ was. Look the

458
00:40:55.400 --> 00:41:00.880
two fates. I always got those
two mixed up. Wells, shame on

459
00:41:00.920 --> 00:41:09.840
you, Andrew. So so yeah, the issue is that it's it's always

460
00:41:09.920 --> 00:41:14.639
about reference frames. It's about how
you see, you know, how you

461
00:41:14.800 --> 00:41:20.719
a world reference frame sees somebody else
and other things going on in a different

462
00:41:20.719 --> 00:41:23.840
reference frame. So that yes,
if you were at a different point in

463
00:41:23.880 --> 00:41:29.159
the gravitational well you would you would
see talent progressing at the different speed,

464
00:41:29.239 --> 00:41:31.599
and it would depend on where you
were in the gravitational well as whether that

465
00:41:31.679 --> 00:41:35.719
was faster or slower. Exactly as
you've said, perfect, All right,

466
00:41:35.800 --> 00:41:40.239
thanks JJ. The next question comes
from Colin. Hi. This is Carlin

467
00:41:40.639 --> 00:41:50.400
from Aballene, Texas. And in
your last episode you had the researchers say

468
00:41:50.800 --> 00:41:58.320
they calculated the trajectory of the comment
or asteroid that was outside our solar system.

469
00:41:58.960 --> 00:42:04.599
But couldn't it just as easily come
shrug the orc cloud because it surrounds

470
00:42:04.679 --> 00:42:12.719
us here. Thank you, Thank
you, Colin, We do too,

471
00:42:13.079 --> 00:42:17.400
Thanks Colin. Um. I think
we can dismiss the aort cloud theory because

472
00:42:17.440 --> 00:42:22.960
of the speed of these particular things. See, you don't leave me,

473
00:42:22.159 --> 00:42:25.159
you don't need me, and you
don't I'm just remembering what you taught me,

474
00:42:25.199 --> 00:42:32.159
Fred. Yeah, that's right.
So um Or cloud comets come in

475
00:42:32.760 --> 00:42:38.400
at certain velocities. I can't remember
what the maximum is for a cloud commet,

476
00:42:39.400 --> 00:42:46.000
but I've read wait for it you
you ought to know? Oh well

477
00:42:46.039 --> 00:42:50.239
that was a good one. Yeah, that's so good one. I like

478
00:42:50.360 --> 00:42:55.079
that one. You ought to take
notice of the blocked cloud. Yes,

479
00:42:55.840 --> 00:43:02.199
anyway, Yeah, Orts was a
very very competent astronomer who did a fantastic

480
00:43:02.239 --> 00:43:08.320
amount of interesting science in the early
post war years. Perst second, anyway,

481
00:43:09.039 --> 00:43:15.480
that's all about so work. Cloud
comets coming from the old cloud at

482
00:43:15.599 --> 00:43:22.239
velocity x, but something interstellar would
come in at two x or x plus

483
00:43:22.320 --> 00:43:24.920
fifty kilometers per second or something like
that. They're they're much faster, So

484
00:43:24.960 --> 00:43:31.639
that that's the that's a critical difference
between you know, an exo asteroid perhaps,

485
00:43:31.920 --> 00:43:37.719
or or or a comet asteroid of
body that's come out from the old

486
00:43:37.760 --> 00:43:43.440
cloud. So it's all about it's
a matter of degree. Yeah, if

487
00:43:43.480 --> 00:43:47.920
if an exo asteroid just happened to
impact something in the or cloud and send

488
00:43:47.920 --> 00:43:53.239
it hurdling our way, you'd still
know the difference, wouldn't you. Yeah,

489
00:43:53.480 --> 00:43:59.880
you, um, you probably would
actually because you know, I mean

490
00:44:00.199 --> 00:44:02.480
this is along the lines of the
theory of that object that we're talking about

491
00:44:02.840 --> 00:44:07.039
last week, that it may have
been disturbed by Planet Night, had they

492
00:44:07.079 --> 00:44:12.760
gravitational tugged by Planet Night. Yeah, but it's still coming in at an

493
00:44:12.840 --> 00:44:17.480
excess velocity. That's correct. All
right, very good, Thank you,

494
00:44:17.519 --> 00:44:22.599
Colin. Lovely to hear from you. And we've got our final question for

495
00:44:22.639 --> 00:44:30.239
this week from Andreas. Hi Andreas
from Sweden here and thanks for a great

496
00:44:30.599 --> 00:44:35.320
podcast. So I have a question
I would like to get your input on

497
00:44:36.119 --> 00:44:37.159
as you can, as we can, all field, the world is kind

498
00:44:37.159 --> 00:44:43.320
of moving in our direction having two
major bay power blocks, Like on the

499
00:44:43.360 --> 00:44:45.639
one side we have the US and
Europe and on the other side we have

500
00:44:45.760 --> 00:44:50.199
China Russia. So which kind of
breaks back the feeling of the old space

501
00:44:50.320 --> 00:44:55.840
range in the US and sub which
propels things forward and about. But if

502
00:44:55.840 --> 00:45:00.519
we look from the perspective of humanity, do you believe having these two competing

503
00:45:00.519 --> 00:45:05.800
blocks, it's better? And if
we all came together, it's like one

504
00:45:05.920 --> 00:45:09.880
happy space family reaching the stars together. So what do you think is better

505
00:45:09.920 --> 00:45:16.760
for a scientific progress and expiration?
Is it collaboration or competition? Altima,

506
00:45:17.719 --> 00:45:22.079
great question, Andrea so well.
As a matter of fact, he's forgotten

507
00:45:22.079 --> 00:45:27.000
North Korea. I just finished watching
season three for All Mankind and they were

508
00:45:27.000 --> 00:45:31.800
the first to step on Mars.
Oh okay, so I hope that wasn't

509
00:45:31.800 --> 00:45:36.920
a spoiler for anybody. Good growth. Sorry, block here is too late.

510
00:45:37.199 --> 00:45:39.639
Yeah, the space race has changed. It used to be the US

511
00:45:39.800 --> 00:45:45.000
and Russia and or the Soviet Union, and now it's the USA, Europe

512
00:45:46.159 --> 00:45:52.159
and Russia and China. Although they
do tend to work independently, they do

513
00:45:52.239 --> 00:45:57.639
collaborate. But what we are seeing
is that we've got collaboration from just about

514
00:45:57.639 --> 00:46:00.039
all on Sundry, maybe to a
lesser degree each China, but they're not

515
00:46:00.159 --> 00:46:06.920
completely blocking everybody out, and one
would hope, and we do see this

516
00:46:07.000 --> 00:46:09.519
a lot in astronomy and space science, is that they do share data,

517
00:46:09.559 --> 00:46:15.760
they do share information, they do
share resources, they work together. So

518
00:46:15.920 --> 00:46:20.440
I from my perspective, I think
it's good the way things are going at

519
00:46:20.480 --> 00:46:24.639
the moment. What worries me is
that someone will get somewhere or find something

520
00:46:24.679 --> 00:46:29.039
and say, well, we we're
not going to share that. We're going

521
00:46:29.079 --> 00:46:31.639
to mind the hell out of it
and keep it for ourselves. Um.

522
00:46:32.320 --> 00:46:39.280
I don't know, it's it's a
I'd rather be a cooperative venture than one

523
00:46:39.320 --> 00:46:44.480
of conflict, although conflict has also
proven to be the mother of invention in

524
00:46:44.639 --> 00:46:49.119
history, in the history of humanity. So cut oath ways, as far

525
00:46:49.159 --> 00:46:52.079
as I think that's andreasis points,
isn't it that soon? You know,

526
00:46:52.159 --> 00:47:02.760
we we gained enormously in the nineteen
sixties by that geopolitical competition between the Soviet

527
00:47:04.000 --> 00:47:09.280
Yes and the Western Bloc, in
particular between Soviet Union and NASA SOU.

528
00:47:13.000 --> 00:47:21.199
But I do think, you know, you've got to kind of bring together.

529
00:47:22.199 --> 00:47:25.800
There are a number of ways of
looking at this, maybe space can

530
00:47:27.320 --> 00:47:32.639
be a beneficial thing in terms of
international relations rather than in terms of technological

531
00:47:32.679 --> 00:47:38.280
development. So you're still seeing,
i suppose, the last vestiges of that

532
00:47:38.320 --> 00:47:45.559
with the International Space Station, which
still has Russian and American astronauts and cosmonauts

533
00:47:45.760 --> 00:47:55.119
basically collaborating in a fantastic way.
And so space diplomacy I think still has

534
00:47:55.119 --> 00:48:05.679
a place in the the world's future, and I've often wondered whether, yes,

535
00:48:05.760 --> 00:48:10.679
there's there's certainly competition at the moment, and a lot of that is

536
00:48:10.679 --> 00:48:14.360
is to do with the rise of
China, the fact that you have a

537
00:48:14.440 --> 00:48:17.639
nation here that wants to assert itself
as a as a world player on a

538
00:48:17.679 --> 00:48:22.599
world stage, with a different political
system from what the Western world has,

539
00:48:23.519 --> 00:48:30.519
and that's that is perhaps one of
the reasons why we're seeing such really capable

540
00:48:30.760 --> 00:48:40.840
and quite notable achievements from the China
China National Space Agency Administration SAM. I

541
00:48:40.960 --> 00:48:50.159
think perhaps looking further into the future, when we're talking about flights to Mars

542
00:48:50.960 --> 00:48:57.000
human exploration of Mars, I suspect
that will turn out to be so expensive

543
00:48:58.679 --> 00:49:05.159
that the only way we'll really make
it work effectively would be to have international

544
00:49:05.239 --> 00:49:08.599
cooperation, and it may well be
that we might see a new era of

545
00:49:09.840 --> 00:49:16.840
warm and fuzzy international corporation, perhaps
comparable with what we saw around the time

546
00:49:16.840 --> 00:49:21.480
of the end of the Cold War. When that would say, though,

547
00:49:21.519 --> 00:49:27.840
the war in Ukraine did lead to
space tensions between the US and Russia,

548
00:49:28.679 --> 00:49:31.800
but it was something that was happening
on Earth that caused that. Yeah,

549
00:49:31.840 --> 00:49:36.599
and I'm pretty sure the people that
were in space at the time really didn't

550
00:49:36.639 --> 00:49:39.559
want to have a bar of it, but they were following orders. Yes,

551
00:49:39.639 --> 00:49:45.960
that's right. I can't rememb whether
or mentioned that when I was at

552
00:49:45.000 --> 00:49:51.400
the Committee on the Peaceful Uses of
Outer Space that meeting in February, that

553
00:49:51.480 --> 00:49:55.159
those geopolitical tensions were very, very
evident in some of the comments that were

554
00:49:55.199 --> 00:50:01.159
being made by delegates of certain nations, and it was all about the war

555
00:50:01.239 --> 00:50:07.000
in Ukraine. So there is so
when you've got something like that going on,

556
00:50:07.039 --> 00:50:15.320
then it really clouds the issue.
But all credit to astronauts cosmonauts for

557
00:50:15.559 --> 00:50:20.880
sticking together up there in the International
Space Station and to their respective space agencies

558
00:50:20.920 --> 00:50:30.360
for actually negotiating diplomatically. Ross Cosmos
had a Buyer brand head who has now

559
00:50:30.400 --> 00:50:36.599
been removed. He's now in Ukraine. Actually this Dimitri R. Godson was

560
00:50:36.639 --> 00:50:38.119
that his name? Yeah, that
sounds about right. Yeah, yeah,

561
00:50:38.639 --> 00:50:46.199
he's so. And we've had far
kind of fewer belligerent signals from ros Cosmos

562
00:50:47.039 --> 00:50:52.000
since then, although you know,
the internal politics might be the saying,

563
00:50:52.119 --> 00:50:57.360
but we've got you know, still
in the space station itself. It is

564
00:50:57.559 --> 00:51:01.400
business as usual, which is quite
a quite extraordinary, quite extra it is.

565
00:51:01.480 --> 00:51:09.079
It is, it seems in terms
of space exploration and even being close

566
00:51:09.159 --> 00:51:14.880
to home orbiting in the International Space
Station, they tend to leave the politics

567
00:51:14.880 --> 00:51:19.639
to the politicians and up there,
away from it all, it's a it's

568
00:51:19.639 --> 00:51:23.199
a different world and they all get
along most famously much of the time,

569
00:51:23.440 --> 00:51:28.480
as far as we're aware. And
yeah, and I hope it stays that

570
00:51:28.559 --> 00:51:34.119
way. And yeah, I hope
you're right about the future of exploration to

571
00:51:34.239 --> 00:51:38.840
Mars. Maybe maybe it will require
international cooperation and to make it, to

572
00:51:38.920 --> 00:51:42.760
make it happen, bring everybody together. I think that would be a great

573
00:51:42.800 --> 00:51:47.559
thing. Thank you so much.
Andrea's a fantastic question. We don't usually

574
00:51:47.559 --> 00:51:53.079
get into politics, but that was
that was a good one. That brings

575
00:51:53.159 --> 00:51:54.719
us to the end of the show. Of course, if you do have

576
00:51:54.840 --> 00:51:59.320
questions for us, you can send
them through our website. The AMA table

577
00:51:59.400 --> 00:52:01.440
or the send us you or Voice
message tab is the way to go.

578
00:52:01.960 --> 00:52:06.440
You can send us text questions as
well. Don't forget to tell us who

579
00:52:06.440 --> 00:52:09.000
you are and where you're from,
and peruse the Space Nuts shop while you're

580
00:52:09.039 --> 00:52:14.199
there. There's nothing worth buying,
but do you do it anyway. Thank

581
00:52:14.239 --> 00:52:16.280
you. As always, Fred has
been a great pleasure. Great to spend

582
00:52:16.320 --> 00:52:22.119
some time helping people understand space and
everything, and although half the time they

583
00:52:22.159 --> 00:52:27.760
help us understand a bit more too, so good Thank you, Fred,

584
00:52:28.440 --> 00:52:31.719
pleasure I was always Andrew look forward
to speaking next week. We will.

585
00:52:31.800 --> 00:52:37.599
And thanks to Hugh in the studio
for sending messages through from our live audience

586
00:52:37.639 --> 00:52:40.320
when we while we were according today, oh my gosh, I said something

587
00:52:40.400 --> 00:52:44.480
nice about Hugh that won't happen again. And from me Andrew, don't clear

588
00:52:44.519 --> 00:52:46.239
you. Thanks for your company on
this edition of Space Nuts. Catch you

589
00:52:46.280 --> 00:52:52.280
on the next episode. Bye bye. You'll be listening to this Space Nuts

590
00:52:52.320 --> 00:53:00.360
podcast available at Apple Podcasts, Google
Podcasts, Spotify, iHeart Radio, or

591
00:53:00.440 --> 00:53:05.079
your favorite podcast player. You can
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592
00:53:05.480 --> 00:53:09.480
This has been another quality podcast production
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