#420: Moon Water & Nemesis: Unveiling Lunar Mysteries and Stellar Theories

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Hi there, thanks for joining us
again on Space Nuts Q and A edition.

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My name is Andrew Dunkley. Lovely
to have your company on this episode.

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We're going to be answering some audience
questions from Mikey. He is asking

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a really interesting question. Can we
drink water that is on the moon,

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as in moon water or lunar water? Would that be a good idea even

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if we clean it. That's a
good question. We'll see if we can

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come up with an answer for that. Sean is asking us about Nemesis theory,

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and Rusty has a question about the
Hubble constant. That's all coming up

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on this Q and A edition of
Space Nuts fifteen. Second guidance is in

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channel ten nine ignition Space Nuts or
three two Space Nurse. As the night

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report it. Neil's good and he's
back again to help and say with all

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of that, Fred, what's in
a stormer? Tell our Fred Tiller?

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Undrew, fancy seeing you here.
Indeed, it's lucky never left really well,

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I did, obviously because I've got
a coffee. Now you have,

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yes, all right now, we
do have a few interesting questions to deal

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with, and we might get straight
into it. Our first question today comes

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from Mikey. Hey, Fred,
Andrew Mikey from Illinois with a quick question.

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So, eventually, when we get
to the moon in Mars and start

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using the water available to us there
for things such as drinking, should we

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drink that water? I mean,
I know that we'll use whatever ways and

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processes we know how of now to
clean that water and purify it like we

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do on Earth. But are there
chances that there will be stuff in that

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water that we might not even know
exists. Yeah, that we might not

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have ever seen before that could have
detrimental effects to the human body. It

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makes sense to me that you would
drink the water that's available to you after

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purifying it, but like it also
just raises concern in my brain that maybe

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something will be in that water that
we don't yet know. Would you guys

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drink the water after bem purified the
first time the tenth time? Curious what

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you guys have to say about that? Thanks, thank you, Mikey.

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Well, I've drunk some pretty horrible
stuff in my life, probably worse than

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water from the Moon, so I
probably would. It's an interesting question,

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though, Fred, because is it
possible there's something in the water that we

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don't know about. There are things
on the Moon that aren't readily available on

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Earth. So could it be something
in the water. And it's a good

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question, and thanks Mike for asking
it because it goes to the heart of

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something we've talked about before as well. But yeah, I mean, I

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guess, taking you know, the
question at face value, what if there's

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something that's not known to science that
is in the water that could be harmful

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and that we we you know,
with all our checking and testing of the

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water samples, basically people saying Okay, that's fit to drink, and yet

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there's something in it, particularly perhaps
perhaps with Martian water, maybe some sort

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of Martian microbe that we haven't got
any way of detecting. I still drink

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it, Actually, that's I think
I would, And that's because I,

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you know, I'm a scientist.
My colleagues would have tested it to death.

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And so if there was something in
it that we didn't know about and

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it had an effect on me,
So if I grew antlers all of a

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sudden or something, it would be
a big scientific discovery. That would have

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been part of it, right,
Fred Watson with antlers, But there is

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something a bit more perhaps realistic and
that will clearly have to be dealt with.

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That we can discuss, and we've
discussed it before, because the water

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on the Moon and on Mars will
probably not have the same isotope ratio as

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the water on Earth. It will
have a different fraction of heavy water it

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from the water that we have on
Earth. Okay, and we you know,

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there'll be a different ratio doing normal
water and heavy water. Remember that

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heavy waters it's sometimes called detour rather
than H two O because the D is

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deuterium, which is hydrogen in a
in a heavier form, it's called heavy

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hydrogen with an added neutron. So
and we're not we're not talking about the

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heavy water from a nuclear reactor.
Let's get that clear. This is this

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is natural heavy water. Yes,
it is. That's that's correct, that's

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right. Uh. And you know
we've we've done measurements of comets which are

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made device and discovered that the proportions
of heavy water to normal water are different

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from what they are on Earth.
And so that's something that does make the

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water different in a comet. And
it's likely that the water on the Moon

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and Mars perhaps came from comets,
so it may well have a different isotope

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ratio, so different, a different
basically quantity of portion of heavy water to

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normal water now in different balance.
Indeed, that's correct, a different balance,

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yeah, which we talked about at
length in a previous episode of Space

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Nuts. And you know, the
question is can you drink heavy water?

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The answer is you can. If
you have smaller amounts, it won't affect

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you. But if you drink too
much of it, you'll start getting a

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different effect because it's more dense.
That's why it's called heavy water. It's

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more dense than normal water. Excuse
me. So, you know, if

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you've got differences in the density of
the liquid that's going around in your body,

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and in particular, I think that
perhaps the really sensitive region is the

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fluids in your ears. If they
suddenly start getting heavier, you might start

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getting noisier and things of that sort
before because your your balance is affected by

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the water. But if you drink
too much of it, then you've got

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this higher density running through your body. But it would be very toxic.

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It would probably be fatal if you
drink you know, if you drink pure

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heavy water for a long period,
I don't think you'd be very well.

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No, Yeah, we have touched
on that before, and it's yeah,

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it's an interesting it's an interesting problem
that they faced. I was doing a

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bit of research on this particular question
because it fascinated me so much. There

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was an article in space dot com
in January this year and two of the

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major space agencies have said, we're
going to be using the water on the

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Moon ultimately, but we need to
filter it. And they've called for public

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assistance on a project called Aqua Lunar. Yeah, and they want people's ideas

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on how to filter the water on
the Moon so it could be consumable.

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So they are actually thinking about drinking
the water on the Moon. They might

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have to do a bit more homework, but they've opened this competition up to

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people in Canada and the United Kingdom. Now. I think the deadline was

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April the eighth, so it'll be
interesting to see what comes out of that.

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But they're certainly looking pretty seriously at
making that resource available for consumption.

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But if you yes, I mean, but if you do have a significant

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ratio of heavy water to normal water, no matter how much you filter it,

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you're not going to get rid of
that. So it's an interesting question.

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Should you be drinking if there's a
large amount of it. Indeed,

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so, as I said at the
beginning, I probably would have a go.

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I would Yeah, I wouldn't mind. I mean, on one glass

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of slightly heavy, heavily laden water, wouldn't wouldn't kill you. But if

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it's already I had to live on
for a long period of time, Yeah,

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it probably would take a while.
That's right, probably would. It's

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the figure I've read here. If
you have the amount of heavy water in

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your body, if it reaches twenty
percent of the total water in your body,

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it could be lethal. So you've
got to you've got to watch out.

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Yeah. Indeed, all right,
great question, Mikey, thanks for

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sending it in. Our next question
comes from Sean. I am sure.

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I'm from Noting up in England,
and I heard about Nemesis theory and that

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there might be a small sun in
our sailor system somewhere. I wondered whether

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there was any possibility of this and
whether this could be planet nine if it's

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like a small neutron star. Okay, lot forward, tearing you answer,

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bye, Thank you, Sean.
Nemesis theory first postulated I love that word

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in nineteen eighty four, and you
know, they're talking about the potential for

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a small sun around ninety five thousand
au from our main son beyond the Oort

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cloud is where they're thinking it might
be. So is that possible thread is

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that could that be Planet nine or
could it be something else, or could

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it just be a complete myth?
So yeah, so you've got to look

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at why that was hypothesized. You're
absolutely right and do it. It's something

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that was proposed by astronomers back in
the eighties and it's sort of it's not

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been disproved. Actually, it's still
you know, it's in the background of

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what we do in the world of
astronomy. Is there an object which would

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have been originally the Sun's binary companion
and it still is in the sense that

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the hypothesis is that this object is
in orbit around the Son, or the

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two objects are in orbit around the
common center of gravity, as distinct from

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I'm just going to say this briefly
that there are other theories of things like

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this, and perhaps the best known
one is Nimiu. Niberu is the supposedly

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hostile star that's going to consume the
Earth and we can't see it because he's

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on the other side of the Sun. I think Naberia has got its own

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cult and it's complete rubbish, absolute
rubbish. And in fact, I can

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quote Brown Cox. He didn't say
this to me, but I heard it

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said, if anybody else mentions the
bullshit planet Nibiu, I'm going to throw

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a copy of Newton's prink Kipia at
their head. That's right, I remember

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that. Yeah, yeah, that's
right. So, you know, Brian,

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Brian summarized it in perhaps a more
forth right way than I would,

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But yeah, it's rubbish. Nemesis, however, is Nemesis is different,

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and it's thought to be you know, it's the hypothesis is that there is

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the Sun's binary companion, the star, the companion style that the song was

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born with, because we know that
most stars are born in pairs that which

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we've never found. We've never been
able to identify that companion of the Sun.

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And the hypothesis is that he is
out there lurking, as you said,

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you know, one and a half
times what was it one and a

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half light years or something of that
sort away from our own planet. Yeah,

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ninety five thousand astronomical units the distance
between the Earth and the Sun.

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So why do people postulate it.
Is it just that we, you know,

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we do think that the Sun has
a lost companion, a lost sibling

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somewhere. Yes, that's partly it. But there is more to it,

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and that is and this is really
the reason why this was hypothesized, and

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it actually goes back to some work
that colleagues and mine were involved with around

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actually around the same time, in
fact, before the Nemesis hypothesis, in

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about nineteen twenty nine. The idea, and this seems to be supported by

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the geological record that on a timescale
of twenty six or twenty seven million years,

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you get repeated mass extinctions. So
you've got this periodicity in mass extinctions,

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if I can put it that way. So the geological record, the

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fossil record, every you know,
as you dig down through the Earth's crust

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and you look at the different layers, geological layers, every twenty six million

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years or thereabouts, you find that
species are being made extinct, they disappear.

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And the suggestion is that possibly this
is to do with the orbit of

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Nemesis. If it comes closer at
part of one part of this orbit than

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another, then it will have tidal
disruption of the Oak Cloud the York Cloud

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will then bombard stuff into the inner
Solar System and you get mass extinctions.

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It was my two colleagues, Victor
Klobe and Bill Napier in nineteen seventy nine

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who first suggested that. They wrote
a book called The Cosmic Serpent. They

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were a bit more specific about some
of the covets that were involved, but

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that was the general theme. But
they didn't postulate there being a planet,

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sorry another star doing this. They
postulated that as the Sun goes round in

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its orbit around the Galaxic center,
it periodically passes what we call giant molecular

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clouds, which are stellar birthplaces,
and in doing that, it feels gravitational

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tidal disruption from those objects and you
get the same effect. You get stuff

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being dropped in from the Oak Cloud
into the Inner Solar System and potentially mass

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extinctions. So that's rather different theory, but that both those theories are still

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lurking in the background. The search
for planet nine is much more local.

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We're looking for an object that's much
nearer, measured in hundreds of astronomical units

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rather than tens of thousands, which
you'd have to be if you had a

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periodicity of twenty six million years or
so, you've got to be looking at

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something a long long way from the
Sun. So planet nine is, you

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know, nearer nearer objects, a
nearer object if it exists, which is

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perturbing the orbits of trans Neptunian asteroids, things like the Koiper melt objects and

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other ic I see worlds out there. So I think Nemesis falls into the

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same basket almost as Planet nine.
We've got this what you might call circumstantial

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evidence that there's something going on there, and there is a theory that sort

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of kind of goes some way towards
explaining that. And that's the case with

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planet nine and the Transceptunian objects.
With Nemesis and the mass extinctions, a

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lot more research I think has been
done on both of them than we're discussing

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here. Various ideas have been eliminated. It's instructive to go, as I'm

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sure you have Andrew to the Wikipedia
page on Nemesis. It's very, very

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very instructive. Let me summarize by
reading what the last sentence in the Wikipedia

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entry on Nemesis is, which reads, according to a twenty eleven NASA news

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release, recent scientific analysis no longer
reports the idea that extinctions on Earth happen

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at regular, repeating intervals, and
thus the nemesis hypothesis is known no longer

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needed. So you know, it
brings geology and astronomy together, but it

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looks as though the geology no longer
supports it. We know much more now

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about the geological record than we did
in nineteen eighty four, so maybe nemesis

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a kind of Yeah, well,
certainly sounds like it has absolutely nothing to

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do with planet nine theory. And
even if nemesis does exist, it's probably

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too far off to have any real
effect by the sound of it, until

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you get until it comes close enough
to disturb the outcloud, and we suddenly

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get bombarded by comments. Yeah,
good point. That's which is the point

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that they're making this. Hence the
name. Hence the name nemesis. I

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suppose indeed, and that's a fact. There's a coincidence here because one of

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my colleagues who were mentioned the Royal
Observatory in Edinburgh, Victor cloven Bill,

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and the Victor was my boss,
actually working on different sorts of stars.

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But Bill went on now I lives
in Northern Ireland. He wrote a book

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called Nemesis. It was a science
fiction novel. Now I've read it,

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you probably read it. It's actually
okay, just over there. Yeah,

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but it was about an asteroid rather
than a star. Yeah, and it

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was how they stopped a hitting Earth
that which was an actual workable possibility.

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It's one of the theories they've been
working with to deflect or divert an asteroid

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away from Earth should it be a
threat. It's a really good book.

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Yeah, I read it some time
ago and I really enjoyed it. Great,

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great idea, and thanks for bringing
up the question. Thorn Thorn sean

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nemesis. Probably not Planet nine,
but yeah, it's certainly something that's got

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a lot of people speculating. This
is space nuts. Andrew Dunkley here with

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Professor Fred. What's okay. We'll
take your space nuts next up. And

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our final question today comes from Rusty
and it's Rusty and Dinna Grum just been

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listening to your episode four oh seven, and it's just want to ask the

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question regarding the Hubble constant. The
CMB method you sixty seven kilometers per second

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for megapasic, and the standard candle
method yields seventy three kilometers per second per

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mega parsic. Is it possible that
the interstellar medium is causing the standard candles

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to lose some intensity over distance,
In other words, some of the light

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being absorbed by the interstellar medium.
If that was the case, then it

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would appear that the CMB method eel
in sixty seven jelem this per second might

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be closer to the mark. Is
that possible? Thank you, Rusty.

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Rusty always insightful, But again,
as I mentioned earlier, has an idea,

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so we should discuss that. But
yeah, the Hubble constant we did

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speak about recently because of that ongoing
differential in the expansion rate of the universe

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that they can't figure out. Yeah, the Hubble tension is called freends figured

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it out. What's the answer,
and sly, I think Rusty I was

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either, which I'll heill to with
a bit, but just let me just

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let me explain what the gop the
Goog words are that Rusty used. Very

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he knows, you know, Russy
is well across all this, so these

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probably Goog terms that we use are
familiar to him, but not to everybody.

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So those figures measured in kilometers per
second per killer passec, per mega

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passecad mega band kilometers per megapast sic. Just giving a blanket understanding of what

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that is. It's how fast the
universe is expanding. Now, it's it's

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it's expansion speed. The further out
in space you look, the more rapidly

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things are moving away from you.
And that's all that does. It puts

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it into numbers. But as Rusty
says, we get two different estimates.

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Sixty seven comes from the cosmic microwave
background radiation what Rusty correctly describes as the

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CNB and it's that's cause by looking
at the patterns in the cosmic microwave background

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radiation. We mentioned that in a
recent episode of the Space Nut's Chat that

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there is a pattern of slightly higher
and lower temperatures in the cosmic microwing background

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radiation, and that pattern gives you
a value for the Hubble constant. And

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exactly as Rusty says, when you
look at standard candles, and in this

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case these are super and over explosions
at great distances, usually then you get

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a different anti. You get seventy
three kilometers per second per megabasic. Now

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rust is thinking is right on the
money. But astronomers think the same way,

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and so they would be looking for
any evidence of some influence of the

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interstellar medium on the You know,
the measurements that we make of supernova.

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There's an analogue that perhaps second point
to here when we measure the brightness of

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stars in this in space normally,
if you know what type of star it

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is, you know how intrinsically bright
it is, And if you measure it's

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apparent brightness from the Earth, that's
a measure of how far away it is,

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because you know it's again it's a
standard candle. You know how intrinsically

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bright it is. If you measure
its brightness from Earth what we call the

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apparent magnitude, then it's a very
easy calculation to work out how far away

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it is. But then maybe intervening
material and in fact the nearly always is

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because space is pretty dusty, it's
got dust in it. Yeah, the

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dust tends to dim the light from
the star, and so that means it

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looks as it's further away than it
actually is. Now, is that the

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right way around? Yes, it's
dimmer. It's dimmer, so you think

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it's further away. Just got to
think about this. Sometimes these things work

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not the way you want them to. So so how can we tell if

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there's dust there. Well, it
turns out that does something to light,

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and we think of it as smoke, but it's it's more like smoke.

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What we call it dust. What
it does is it scatters out the blue

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light, just like the atmosphere is
scattering blue light. And so a star,

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a star's light, if it's passing
through dust, will be reddened.

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And you can measure how much that
reddening is because you know what type of

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star it is, so you know
what its color is. And if the

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color is moved to the red,
you'd say, ah, there is dust

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there. Something we call the color
index, and that lets you correct the

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distance that you're looking at, so
you can correct the standard candle because you

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know that what's happened is the dust
in space has kind of put a signature

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on the light coming from the star, which tells you that it's not just

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empty space in between. And similarly, the light from supernov will have and

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printed on them a signature of the
interstellar medium. And that's something that some

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of those signatures and mysteries actually there
in interstellar space. For a long time,

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there's been a signature in space that
we really didn't know what it was,

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but it turns out that it's things
like bucket balls. It's complex carbon

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molecules that absorb light in a particular
way. So what I'm saying is that

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because the light from these distant standard
candles has been analyzed to death, that

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any impact by the interstellar medium will
have been compensated for because it will have

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left a fingerprint on the light or
a signature on the light which we can

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detect. So I think the answer
to Russy's question is, Hey, I

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like your thinking because you're thinking along
exactly the same lines that astronomers think.

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And b I think I think the
old tar that we would have known had

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it been some effect of the actually
the intergalactic medium, the space between between

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stars, that would be causing that
phenomenon. And there is a standard ruler

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method as well that just looks at
the distance, the difference in the characteristic

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size of galactic clusters and things of
that sort, which also gives that seventy

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three killing meters per second the mega
passex. So it's not just the standard

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candles. But thank you, Rusty, a very stimulating question. As always,

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Yes, back to the whiteboard and
get a new packet of sharpies because

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you still calculating to do yes.
Not the solution, but I'm glad someone's

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thinking about it. I think a
lot of people are. It's no solution

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to the variations in the Hubble constant. Thanks Rusty. Remember last week,

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Fred, we answered the question from
Craig, who identified himself as a science

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fiction writer, and I said,
tell me what you what you run,

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what your books are, and I'll
have a look at them. Well,

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he sent me a copy of his
book. It's called Free as Flight and

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it's his tribute to Heinland's Juvenile series. So I'm going to read that and

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let you know what I think in
about two or three years time i read.

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But he also sent me his Amazon
page for Free as Flight Kindle edition

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by Craig Miller, if you want
to look it up and ever read of

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Craig's book. Who sent us a
question last week? He said he was

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funny because it took me a while
to get that one into the system.

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He said, I thought my question
had fallen off your desk. Well it

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virtually did, Craig, because it
actually fell off my computer because I did

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a computer update and it wiped everything
and it took me ages to find all

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this stuff. But it turns out
there was a corruption in my Microsoft one

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drive cloud software which was confusing my
account with another account that I had at

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work and they got jumbled, which
has happened to me a couple of times.

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So and then it was trying to
find a drive that didn't exist on

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my computer, and dogs and cats
ended up living together. It was all

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over, Red Rover. But thanks
for a copy of the book, Craig.

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I'm looking forward to reading that.
And yeah, look for Free as

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Flight if you want to read Craig's
book as well. That brings us to

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the end, Fred, Thank you
so much. We'll catch you next time.

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It sounds great, Andrew, and
it'll be as exciting as it was

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this time, I'm sure, maybe
more so more exit. No, not

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at all, definitely not all right, See soon Fred, Fred, what's

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an astronomer at large? And thanks
to hear in the studio for what I

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will tell you next week and from
me Andrew Dunkley. Thanks for your company

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and we'll look forward to joining you
again on the next episode of Space Nuts.

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Bye bye, Spacenuts. You'll be
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00:28:59.359 --> 00:29:04.240
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