Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #420: Moon Water & Nemesis: Unveiling Lunar Mysteries and Stellar Theories

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#420: Moon Water & Nemesis: Unveiling Lunar Mysteries and Stellar Theories · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
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
0:38
on this Q and A edition of Space Nuts fifteen. Second guidance is in
0:44
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?
1:03
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
19:02
Professor Fred. What's okay. We'll take your space nuts next up. And
19:12
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
19:25
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
19:56
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
21:32
it's expansion speed. The further out in space you look, the more rapidly
21:37
things are moving away from you. And that's all that does. It puts
21:40
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,
22:40
and so they would be looking for any evidence of some influence of the
22:47
interstellar medium on the You know, the measurements that we make of supernova.
22:55
There's an analogue that perhaps second point to here when we measure the brightness of
23:02
stars in this in space normally, if you know what type of star it
23:08
is, you know how intrinsically bright it is, And if you measure it's
23:14
apparent brightness from the Earth, that's a measure of how far away it is,
23:18
because you know it's again it's a standard candle. You know how intrinsically
23:21
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
23:37
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
23:55
it's further away. Just got to think about this. Sometimes these things work
24:00
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,
24:11
and we think of it as smoke, but it's it's more like smoke.
24:14
What we call it dust. What it does is it scatters out the blue
24:17
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
24:30
star it is, so you know what its color is. And if the
24:33
color is moved to the red, you'd say, ah, there is dust
24:37
there. Something we call the color index, and that lets you correct the
24:44
distance that you're looking at, so you can correct the standard candle because you
24:48
know that what's happened is the dust in space has kind of put a signature
24:52
on the light coming from the star, which tells you that it's not just
24:56
empty space in between. And similarly, the light from supernov will have and
25:03
printed on them a signature of the interstellar medium. And that's something that some
25:10
of those signatures and mysteries actually there in interstellar space. For a long time,
25:17
there's been a signature in space that we really didn't know what it was,
25:21
but it turns out that it's things like bucket balls. It's complex carbon
25:26
molecules that absorb light in a particular way. So what I'm saying is that
25:33
because the light from these distant standard candles has been analyzed to death, that
25:38
any impact by the interstellar medium will have been compensated for because it will have
25:45
left a fingerprint on the light or a signature on the light which we can
25:48
detect. So I think the answer to Russy's question is, Hey, I
25:53
like your thinking because you're thinking along exactly the same lines that astronomers think.
25:57
And b I think I think the old tar that we would have known had
26:03
it been some effect of the actually the intergalactic medium, the space between between
26:07
stars, that would be causing that phenomenon. And there is a standard ruler
26:15
method as well that just looks at the distance, the difference in the characteristic
26:19
size of galactic clusters and things of that sort, which also gives that seventy
26:23
three killing meters per second the mega passex. So it's not just the standard
26:29
candles. But thank you, Rusty, a very stimulating question. As always,
26:33
Yes, back to the whiteboard and get a new packet of sharpies because
26:37
you still calculating to do yes. Not the solution, but I'm glad someone's
26:42
thinking about it. I think a lot of people are. It's no solution
26:47
to the variations in the Hubble constant. Thanks Rusty. Remember last week,
26:52
Fred, we answered the question from Craig, who identified himself as a science
26:56
fiction writer, and I said, tell me what you what you run,
27:00
what your books are, and I'll have a look at them. Well,
27:03
he sent me a copy of his book. It's called Free as Flight and
27:08
it's his tribute to Heinland's Juvenile series. So I'm going to read that and
27:15
let you know what I think in about two or three years time i read.
27:18
But he also sent me his Amazon page for Free as Flight Kindle edition
27:25
by Craig Miller, if you want to look it up and ever read of
27:27
Craig's book. Who sent us a question last week? He said he was
27:32
funny because it took me a while to get that one into the system.
27:34
He said, I thought my question had fallen off your desk. Well it
27:38
virtually did, Craig, because it actually fell off my computer because I did
27:41
a computer update and it wiped everything and it took me ages to find all
27:45
this stuff. But it turns out there was a corruption in my Microsoft one
27:49
drive cloud software which was confusing my account with another account that I had at
27:59
work and they got jumbled, which has happened to me a couple of times.
28:03
So and then it was trying to find a drive that didn't exist on
28:06
my computer, and dogs and cats ended up living together. It was all
28:08
over, Red Rover. But thanks for a copy of the book, Craig.
28:11
I'm looking forward to reading that. And yeah, look for Free as
28:15
Flight if you want to read Craig's book as well. That brings us to
28:21
the end, Fred, Thank you so much. We'll catch you next time.
28:23
It sounds great, Andrew, and it'll be as exciting as it was
28:26
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
28:38
an astronomer at large? And thanks to hear in the studio for what I
28:42
will tell you next week and from me Andrew Dunkley. Thanks for your company
28:47
and we'll look forward to joining you again on the next episode of Space Nuts.
28:52
Bye bye, Spacenuts. You'll be to the Space Nuts podcast, available
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