Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #429: Boeing Starliner Woes & Titan's Liquid Coastlines: Cosmic Insights

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#429: Boeing Starliner Woes & Titan's Liquid Coastlines: Cosmic Insights · Space Nuts: Astronomy Insights & Cosmic Discoveries

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Hi there, this is Space Nuts. My name is Andrew Dunkley. Thank
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you for joining us for yet another episode. In this one, we are
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going to be looking at the latest with Boeing star Liner. They had trouble
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getting it off the ground. Now it looks like they're having trouble getting it
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on the ground. We'll be looking at coastal erosion, not on Earth,
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but on the only other body in our Solar system where we know there is
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a liquid surface and we don't know much about it. They've come up with
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an idea about this particular place named Titan and what might be happening around the
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coast where you don't want to live. We're also going to find out about
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we most likely to form a moon and dark matter and its influence is back
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in the news. That's all coming up on this edition of Space Nuts.
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Fifteen second guidance in Channel ten nine ignition sequence Space Nuts Sie three two one
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Street Nurse and I bought it real good and here to tell us all about
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moons and Titan and star liners and dark matter influences. Professor Fred what's an
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astronomer at large? Hi? Fred? Hi Andrew? How are you doing?
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I'm doing everything I came this day. Warm air condition died on Saturday
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afternoon, just as the temperature was dropping. So we've spent the weekend wrapped
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in blankets and seventy five layers of clothing. And I don't know, we've
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killed a few geese and taken their feathers. We are freezing and you've chosen
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the coolest weekend of the winter to do it. Yeah. Yeah's very pleasant.
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It's quite trull. We just went past the winter solstice, so yeah,
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the shortest day. And yeah, it's rather jilly here at the moment,
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but on well as you do. But I hope you get it fixed
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soon. Anyway, it's not very not very nice when you're out. Conditioning's
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gone blong. No, definitely not. You are yes, gone bung.
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Yeah, yeah, the air the air con has gone bun. That that's
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what's basically happened. Uh. And you you have a studio guest there who
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might make his presence felt sooner or later, named Jordy, so will yes,
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we will welcome him. Is he having a bit of listeners? So
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good? Yeah, it's a tough life for dogs. Let's get started,
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Fred, Let's do a Star Lineer update. I remember when it wasn't so
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long ago that we're trying to get it off the ground, and then they
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didn't, then they did, then they didn't, and they did, and
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finally it got up there too much fanfare, and now NEI they're a bit
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stuck. That's right, it's a It is an interesting story and one that
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I mean. I think what we're seeing is a very cautious approach by both
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Boeing and NASA to this because Boeing contracts to NASA with their star Liner space
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capsule, which is designed to be the second kind of space taxi after the
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Crew Dragon, the SpaceX Crew Dragon, which has been successfully flying up and
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down with astronauts for quite some time now. But there was so this is
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the first test flight, the first crewde test flight of the Boeing star Liner
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with two NASA crew members on board. It has flown twice before, I
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think, without crew and worked well, but there were issues before they left,
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before they left Earth, and the I think it was it was the
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beginning of June when they when they headed up there, the return was scheduled
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for I think fourteenth of June originally, then the twenty sixth of June,
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but now it's been postponed kind of indefinitely, although you can't postpone it completely
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indefinitely because you need to bring your astronauts back. And the reason is that
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there are issues with some of the thrusters, the maneuvering thrusters that the spacecraft
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has. It has, believe it or not, twenty eight of those,
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which is, you know, it's quite a number, which I guess you
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need to position the spacecraft to orient it so that it lines up exactly with
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the docking port on the International Space Station and things of that sort. But
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apparently five of the thrusters have got issues which are apparently helium leaks and the
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helium is something that pressurizes the thrusters. There's also an issue with a well
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valve which is not moving as quickly as it should do. And so what
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they've done is put a hold on returning these astronauts back to Earth in the
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star Liner and then try and you know, fix these problems before it does
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make its return to the planet. I think, yeah, I think there's
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a fairly full program of work for the astronauts up there while they're working the
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while they're living at the space station, so they're not going to be sitting
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twiddling their thumbs, and quite a lot of what they might be doing I
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suspect is to do it with Kenny, to do with getting back home.
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So that's the way the status quote the moment. Of course, it could
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change very quickly. By the time this podcast goes to air. It may
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have changed already, but we wait developments with interest. Yes, absolutely,
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in hope, Paul is well, I look, I know they're sitting there
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regretting that they didn't take their w D forty with them. That's I will
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have solved everything, I reckon. Well, it nobly does, that's right.
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Yeah, I think I've told you the story before about why it's called
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w D forty. You have, but I'll hear it again happily. Well,
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it was quite simply the fortieth variation of the formula, and it's the
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one they got right. But WD is something to do with water dispersal or
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something like that. Yeah, I'm going to look it up right now.
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Good on you. You're somebody who can do more than one thing at a
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time, which I can't. Yeah, it's water displacement fortieth formula. There,
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you are not too far off the mark. I do remember an issue
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that you know the water was highlighted in the name. Yeah, I don't
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know about helium dispersement. Yeah, that's I think they're wrong about HD ninety
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five. Now, Ali, maybe all right, fingers crossed for the bowing
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star line. And look, they've done very very well considering all the problems
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they've had before they got it off the ground for this crude mission. And
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I'm sure they'll solve it. They're probably just been super duper cautious. And
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yes, that's fair enough to moving on. Let's go to Titan, the
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only other place in the Solar System, or the universe for that matter,
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that we know of, that has a liquid surface. This is not a
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liquid surface that you want on Earth. We wouldn't be here if this existed
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on Earth in the capacity that it does on Titan, or we might be
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here in a different form, who knows, But we're talking petrochemicals. And
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one of the big mysteries of Titan is whether or not it's oceans work the
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same way as they do on Earth. And they've been looking into this.
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Indeed, then this is a question that goes back a long way. So
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remember the Cassini mission up to twenty seventeen, when it burned up in Saturn's
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atmosphere. An absolute treasure trove of information that came from it, including radar
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mapping of the surface of Titan, Saturn's biggest moon, second biggest moon in
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the Solar System, and that radar mapping showed very clearly that as suspected actually
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because people thought this was the case. There are season lakes on Titan which
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are of liquid natural gas. Basically, the temperature at the surface is roughly
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one hundred and seventy minus one hundred and seventy degrees celsius, and that's called
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enough for you know, these gases ethane and methane to be liquid, and
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so liquid natural gas on Titan fills these basins, which are mostly near the
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North Polar region, so the sat turns sorry Titans. North Polar region has
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its whole array of lakes and seas which show up dark on the radar reflections.
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They're actually you know that that's kind of how we know that they are
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very smooth because the radar just bounces off them. It doesn't scatter like a
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rough surface does. But the question has always been are there waves on those
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lakes and seas? And there's two schools of thought here. One is that
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they are very smooth, and in fact, I do remember being staggered to
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read once. This is quite some time ago, probably a decade ago,
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that the biggest wavefight on titaned seas was probably a millimeter and that seems,
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you know, not there's not much surfing with the millimeter high waves there,
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that's right, not unless sure iFly? Yeah, so so they they The
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other side of the coin, though, was that occasionally on Titan you get
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bright patches being reflected in the radar beams. And those bright patches are something
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that come and go. They don't stay, they're not permanent, they don't
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last very long. And so one suggestion for that was that these were wind
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driven waves. You've got storms, basically, that the waves on the surface
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of Titan. Another thought was possibly methane icebergs that you know, didn't we
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talk about that one that Bill We did. Yeah, And maybe the methane
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icebergs hang around for a while and then melt or disappear, and so that's
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why these bright things that appeared in the seas look look are temporary that they
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come and go. So a group from a number, well, there's a
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lot of NASA scientists in this scientists from MIT Massasachusetts Institute of Technology, and
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other institutions US Geological Surveys also involved with this work. What they've done is
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taken a different approach. They've looked at the shape of the coastline of these
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lakes and seas, because they've quite intricate coastlines. You know, if you
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look at photographs of them, it's pretty easy to find them. You can
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see river estuaries and headlands and all of that sort of thing, the kinds
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of things that we just think of as being natural coastal features. So they've
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looked at those in detail, and taking the Earth as a model, they've
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said, okay, on Earth, there's two main kinds of erosion of a
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coastline. One is what's called uniform erosion, and that occurs where the coastline
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is actually being dissolved away by whatever chemicals are in the water. And we
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see that in cast country, where you've got limestone with lakes forming in it,
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and basically the water in the lakes dissolves the limestone and so you get
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this what's called uniform erosion. And the other kind is wave driven erosion,
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and wave erosion depends on the wind direction, the wind speed that causes the
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waves. But the interesting feature is that these two different sorts of erosion,
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uniform erosion wave erosion, give quite different styles of coastline, if I can
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put it that way. They wear things down differently. And so the analysis
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of the Cassini images have essentially supported the idea that these coastal features are wave
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driven rather than uniform erosion. Interesting. Yeah, so it's a really neat
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way of trying to work out whether they're away. It's on the seas of
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Titan, and it looks as though that's confirmed as being a possibility. If
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there are waves, that means there must be something driving them. Would that
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have to be wind, wouldn't y? Yeah, that's right. And the
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next step in this research is to try, and you know, by again
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by careful analysis of these coastal features, try and work out what the wind
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direction is and what speed it is the prevailing winds on Titan. The surfers
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that listen to us are very excited to learn of Ye, but that minus
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one hundred and seventy degrees you'd need a heck of a wetsuit. Yeah,
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and you wouldn't want your air conditioning to break down either. No, no,
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definitely not. There is just one PostScript to that story, though,
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and that is that twenty twenty eight, we hope NASA will launch its Dragonfly
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mission, which is an autonomous rotocraft a drone basically, which will be in
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orbit around or it won't be in orbit. It'll be patrolling the landscape of
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Titan. Hopefully we'll land on a beach somewhere and actually have a look at
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these waves and tell us what the waves are like. So, yes,
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Dragonfly is something very much to look forward to. The next big mission to
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Titan. How long it's going to take to get there, But I think
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it's quite a while, So twenty twenty eight launch might be I don't know,
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it might be ten years before it gets there, but at least it's
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on its way. I'm going to find it. Okay, good because we
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need to put it in the diary for Space Nuts for when Dragonfly is deployed
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on Titan. It's July twenty twenty eight, six years to reach. Okay,
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not bad, so twenty thirty four, yeah, we'll still be going
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strong. But then that's away. Yeah, absolutely a problem at all.
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If you'd like to follow up on that story here about the waves on Titan.
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You can find fabulous right up at universe tooday dot com. This is
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space Nuts Andrew Dunkley here with Professor Fred. What's an Okay, we take
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a space nuts now, Fred, let's talk about moons and where to find
15:26
them. And well, it looks like, I mean, we've got one,
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Mars has got a couple, Venus doesn't have any, does it.
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But they're starting to think that the formation of moons is more likely around rocky
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planets. What's the story here, Yeah, so let's just review what we
15:48
know about the origin of our own moon. The current theory about the origin
15:54
of the Moon is that a Mars sized planetism by the name of Fear.
16:00
We've given it a name, even though it longer doesn't exist anymore. That's
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right. It collided with the Moon very early in the history of the Solar
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System. You know, the Solar System might have only been ten or one
16:11
hundred million years old at that time, which is very very new. You
16:15
forming planets. You've got these planetismals charging around all over the place, and
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this collision is thought to have occurred very early on, which excavated an enormous
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amount of material from the Earth. Basically, the amount of energy that was
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put in rendered the surface of Earth molten, so it became a lava world,
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and the debris basically formed a ring around the Earth, which eventually it
16:45
created to become the moon that we are familiar with today. And so that
16:51
is the basic picture. There's still a lot of, you know, places
16:57
where the jury is still out on the angle velocity all of those things.
17:03
The exact massive thear by the angle of velocity, I mean of the of
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the collision that created created the moon. So apparently, when you look at
17:17
these studies, if you've got a high energy impact, what you wind up
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with, and this is the theoretical study, is a disc around the planet
17:30
that's dominated by vapor, where whilst or a sort of gaseous material, if
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I put it that way, while a lower energy impact, you get a
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disc that's dominated by rock basically by dust, silicate silicate dust, and so
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which of those happens apparently will play a big influence on what you get at
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the end of it, you get a moon or whether you just get vapor
18:03
that you know, gas is material that just disperses into space. And apparently,
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and this is This is a kind of technical term that I've not really
18:15
been that familiar with, but it's something called a stream streaming and streaming instability,
18:22
let's get it right, friend, the streaming instability, which is the
18:29
the the deciding factor in what you're going to get. So, so the
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streaming instability comes depending on the velocity of the impact, the energy of the
18:41
impact. And it turns out that the bottom line, as you've probably picked
18:48
up from what I've been saying, is that that the the more the less
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high velocity, the lower energy perhaps you could say, are gentler in pact,
19:00
that is more likely to result in the formation of a large moon,
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Whereas if you've got a high energy impact, you don't you don't get the
19:11
moon. You just get a lot of vapor, a lot of gas that
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heads off into space. So it is, yeah, it's an interesting suggestion,
19:22
and it sort of somehow, to some extent, it reinforces our view
19:29
that perhaps many of the moons of the outer planets the gas giants, which
19:33
are much smaller than the parent bodies, unlike our own moon, which is
19:38
pretty substantial compared with the parent body. It's one eightieth of the mass of
19:44
the Earth. It's why you know it talies with the suggestion that some of
19:48
those larger planets have moons that were really caused by perhaps captured captured material or
19:56
colliding comets, so colliding asteroids, things of that sort, rather than a
20:03
collision process like the one that we we think formed our own moon. No,
20:07
that's interesting because you look at Mars and the two moons of Mars seem
20:15
to be more likely captured objects. That's correct. Yes, we don't really
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know too much about the origin Phobos and demos. They probably are captured captured
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objects rather than something caused by an impact like the one that caused our own
20:27
mot I mean, it's sort of you know, it emphasizes the point really
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that maybe our own moon is quite a rarity because it's it's it's not uncommon
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for smaller bodies to have large moons. And the casing point is is Pluto,
20:48
the dwarf planet Pluto with its moon care on which is I can't remember.
20:56
It's significantly high. I think it's something like one sixth of the mass
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of Pluto. I might be exaggerating that. I'm just trying to remember from
21:04
the New Horizons flyby, but it is quite big. Compared with compared with
21:10
Pluto itself, it's one two hundred and fourteen kilometers across, which is about
21:15
half, yeah, half the diameter of Pluto. Pluto's with more than two
21:19
thousand kilometers. So yes, it's it's you know, there you've got two
21:26
bodies which are similar in size, and they're almost a binary body. And
21:33
we know there are binary asteroids. We see many binary asteroids as of asteroids.
21:38
So when you get to the smaller end of the of the planetismal or
21:42
planetoid spectrum, it seems that large moons are more common. But when you
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when you grow up into when you look at big, bigger planets, bigger
21:52
objects in the in the Solar System, it looks as though smaller moons are
21:56
the way it goes. So the suggestion of this particular piece of research is
22:02
that perhaps small, rocky planets are better at making moons than large ones.
22:10
It comes from a variety of scientists, mostly in the United States. That's
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fascinating. Well, I suppose now if they if they because they've been doing
22:22
simulations to try and prove their theory, what they probably need to do now
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is take a look out there and see if I mean it's probably very difficult.
22:33
Finding an exoplanet hard enough, but we're getting better and better at it.
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But finding moons around those planets, if this theory holds true, you
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probably have better target options. But as we've said before, seeing a rocky
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exoplanet is much more difficult than a gas giant, isn't it. That's right.
22:52
I think there's one or two suspected moons. There's nothing that's been guaranteed
23:02
an exo moon. And one of the things that comes to mind, and
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we might have talked about this a year or so ago, is with gravitational
23:10
microlensing. This is where a star with it with planets, passes in front
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of another star in the background, and the gravitational field of the foreground star
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distorts the background star and magnifies it. It actually makes it much brighter,
23:27
and you can detect planets that way, quite small ones, actually much much
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smaller than the other normal planetary detection methods. And I think there was a
23:37
suspected exo moon found in one of the micro lensing experiments that was done a
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few years ago, if I remember rightly, except I think correct me if
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I'm wrong. But haven't they got to say it three times to prove it.
23:53
Yeah, except you don't. With micro lensing, it's a one off.
23:57
Yeah, absolutely right, because you see the story of the planet again,
24:00
they're all invisible, so it just gets a microlensing event name rather than
24:06
a planet name. No fair interesting, all right, If you want to
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look at that story. Space dot com is the website. We can check
24:15
it out to our final story, Fred And this is a this is pretty
24:19
big one actually, and not surprisingly dark matter is in the news again,
24:26
but we're looking at the influence of dark matter and it's it's again questioning our
24:32
understanding of the universe and why things are happening the way they are. That's
24:37
right. So we've you know, we return to this theme so many times
24:42
and so often, but it is interesting. It is a huge part of
24:51
current astronomical research. What is the nature of dark matter? And some people
24:56
question whether it really exists at all. And so this is some research that's
25:02
come out of Case Western Reserve University in the US and goes back to one
25:11
of the methods that was used in the early days of dark matter research to
25:17
determine what was going on. Just to give you a bit of history,
25:21
Andrew dark matter was first postulated actually back in nineteen thirty three by very interesting
25:26
astronomer Swiss American astronomy by the name of Fritz Vicky and VICKI was observing galaxies
25:33
in a cluster of galaxies called the Coma Cluster the northern constellation of Coma Brenises,
25:40
and he worked out that if all he could see was all that was
25:45
there, these galaxies should have gone their own separate ways millennia ago, because
25:51
there wasn't enough mass that he could see that would hold the cluster together.
25:55
And it was then nobody understood that, so it was just ignored basically as
26:02
a curious fact of astronomy that we couldn't explain. And it wasn't until actually
26:07
nineteen seventy that it was raised again by Australian astronomer Ken Freeman. I was
26:11
in touch with Ken last week. He's still going strong. He got the
26:15
Prime Minister Science price for this work. But back in nineteen seventy he said
26:21
that the galaxies that he was measuring, he was looking at the rotation of
26:25
galaxies. We're going too fast to stay together. They should fly apart,
26:30
and that was then confirmed later in the seventies. Nineteen seventy eight by Via
26:33
Rubin, a wonderful American astronomer. She made that she basically put together all
26:41
these ideas to work out that the only way you could get galaxies holding together
26:47
was if they were enveloped in a sort of spherical cloud or halo of dark
26:52
matter. And that's been this sort of status quo ever since. But we
26:56
now have this new research which this takes big bad that's right, takes the
27:04
rotation idea, but looks at the way galaxies rotate millions of light years from
27:12
their centers, in other words, the very outer regions of galaxies. They
27:19
are basically sorry, I've just canceled a call there from something quite famous,
27:25
interestingly said, I'll call you later. They've taken they've looked at large galaxies
27:37
and looked at the way they rotate in their outer, outer most regions and
27:41
discover that it's it looks as though they're still being controlled by dark matter.
27:51
So the bottom line is that they're saying that the dark matter halos, either
27:56
the dark matter haloes are much much bigger than we thought they were, that
28:00
these galaxies are immersed in enormous halos of dark matter, much bigger than we
28:03
thought they were before, or we've got it wrong, and you know that
28:08
we're we're we're we're misleading ourselves by the fact that our understanding of gravity and
28:17
acceleration are incomplete. And this goes back to Mordeheigh Milgram's theory of moond as
28:23
it's called modified Neutonian dynamics, that says that very low accelerations Newtonian dynamics doesn't
28:34
work the way Newton said it did. In other words, you know,
28:37
you push something and it moves, but it doesn't quite work that way a
28:41
very low accelerations. So that's the that's the issue. You know, it's
28:48
it's once again, it's it's challenging dark matter dark matter. We the mainstream
28:56
belief is that it is some form of massive subatomic posts that we have not
29:00
yet discovered. In fact, the sub Atomic Particle Fraternity have worked very very
29:04
hard to try and find whatever this is, but we've failed completely. So
29:11
if it's not a particle, what is it? And this work kind of
29:15
pushes back in the direction of our understanding of acceleration being roll. Yeah,
29:21
I think it's w D thirty nine what it is? Yes, well,
29:27
there you go. It could be could be it is. I'm hoping the
29:34
day will come where we find out what dark matter is and the penny drops
29:40
and we go, yeah, of course it's so simple. Yeah, yes,
29:45
we're not there. No, we're not. And the reason why Mom
29:48
doesn't have a big following is that it sort of lets you down in other
29:52
ways. It might explain the rotation of galaxies, but it can't explain explain
29:57
the behavior of galaxies in cluster in clusters, which is what old Fritz Vicki
30:03
was discovering. There are a few other things that don't work well. In
30:10
fact, you know, to do with the general structure of the universe,
30:12
you tend to need dark matter to make the universe look like it does.
30:17
So the dark matter has still got a lot a lot going for it,
30:21
Andrew, Yeah, sure has. And of course, now that we've talked
30:25
about it, I'm sure we'll get one or two questions and potential theories.
30:30
A lot of our audience do put up theories, which we do like we
30:34
do. Okay, if you want to read that story, it's at Space
30:38
Daily dot com and you'll probably find it on many other pages as well.
30:45
That brings us to the end of this episode. But don't forget to visit
30:48
our website, Space Nuts podcast dot com or space nuts dot io and have
30:52
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the subscribe button if you haven't done so already. That's it, Fred,
31:33
thank you so much. Great pleasure is always under it. Yeah, it's
31:37
becoming quite regular, this isn't it. It's almost like we've been doing a
31:44
fore years. Yes, yes, yeah, all right, thanks, there's
31:49
more. Okay, thanks for it. We'll see you soon. Sounds great.
31:52
Thanks Andrew. Fred Wat's an astronomer at large part of the team here
31:57
at Space Nuts and Hugh back in the studio. He's trying to figure out
32:01
how to use the Internet and from me Andrew Dunkley. Always good to have
32:05
your company. Catch you on the very next episode of Space Nuts. By
32:09
bye. You'll be listening to the Space Nuts podcast available at Apple Podcasts,
32:17
Spotify, iHeartRadio, or your favorite podcast player. You can also stream on
32:22
demand at fides dot com. This has been another quality podcast production from nights
32:29
dot com.