#429: Boeing Starliner Woes & Titan's Liquid Coastlines: Cosmic Insights

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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

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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

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know about the origin of our own
moon. The current theory about the origin

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of the Moon is that a Mars
sized planetism by the name of Fear.

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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

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hundred million years old at that time, which is very very new. You

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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

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created to become the moon that we
are familiar with today. And so that

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is the basic picture. There's still
a lot of, you know, places

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where the jury is still out on
the angle velocity all of those things.

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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

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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

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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

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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

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been that familiar with, but it's
something called a stream streaming and streaming instability,

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let's get it right, friend,
the streaming instability, which is the

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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

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impact. And it turns out that
the bottom line, as you've probably picked

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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,

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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

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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,

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and it sort of somehow, to
some extent, it reinforces our view

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that perhaps many of the moons of
the outer planets the gas giants, which

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are much smaller than the parent bodies, unlike our own moon, which is

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pretty substantial compared with the parent body. It's one eightieth of the mass of

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the Earth. It's why you know
it talies with the suggestion that some of

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those larger planets have moons that were
really caused by perhaps captured captured material or

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colliding comets, so colliding asteroids,
things of that sort, rather than a

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collision process like the one that we
we think formed our own moon. No,

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that's interesting because you look at Mars
and the two moons of Mars seem

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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

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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,

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the dwarf planet Pluto with its moon
care on which is I can't remember.

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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

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the New Horizons flyby, but it
is quite big. Compared with compared with

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Pluto itself, it's one two hundred
and fourteen kilometers across, which is about

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half, yeah, half the diameter
of Pluto. Pluto's with more than two

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thousand kilometers. So yes, it's
it's you know, there you've got two

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bodies which are similar in size,
and they're almost a binary body. And

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we know there are binary asteroids.
We see many binary asteroids as of asteroids.

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So when you get to the smaller
end of the of the planetismal or

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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

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objects in the in the Solar System, it looks as though smaller moons are

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the way it goes. So the
suggestion of this particular piece of research is

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that perhaps small, rocky planets are
better at making moons than large ones.

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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

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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.

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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.

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I think there's one or two suspected
moons. There's nothing that's been guaranteed

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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

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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,

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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

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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.

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Yeah, except you don't. With
micro lensing, it's a one off.

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Yeah, absolutely right, because you
see the story of the planet again,

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they're all invisible, so it just
gets a microlensing event name rather than

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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

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it out to our final story,
Fred And this is a this is pretty

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big one actually, and not surprisingly
dark matter is in the news again,

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but we're looking at the influence of
dark matter and it's it's again questioning our

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understanding of the universe and why things
are happening the way they are. That's

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right. So we've you know,
we return to this theme so many times

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and so often, but it is
interesting. It is a huge part of

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current astronomical research. What is the
nature of dark matter? And some people

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question whether it really exists at all. And so this is some research that's

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come out of Case Western Reserve University
in the US and goes back to one

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00:25:11.440 --> 00:25:17.480
of the methods that was used in
the early days of dark matter research to

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determine what was going on. Just
to give you a bit of history,

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Andrew dark matter was first postulated actually
back in nineteen thirty three by very interesting

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00:25:26.799 --> 00:25:33.400
astronomer Swiss American astronomy by the name
of Fritz Vicky and VICKI was observing galaxies

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in a cluster of galaxies called the
Coma Cluster the northern constellation of Coma Brenises,

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and he worked out that if all
he could see was all that was

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there, these galaxies should have gone
their own separate ways millennia ago, because

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there wasn't enough mass that he could
see that would hold the cluster together.

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And it was then nobody understood that, so it was just ignored basically as

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a curious fact of astronomy that we
couldn't explain. And it wasn't until actually

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nineteen seventy that it was raised again
by Australian astronomer Ken Freeman. I was

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in touch with Ken last week.
He's still going strong. He got the

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Prime Minister Science price for this work. But back in nineteen seventy he said

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00:26:21.200 --> 00:26:25.720
that the galaxies that he was measuring, he was looking at the rotation of

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00:26:25.799 --> 00:26:29.799
galaxies. We're going too fast to
stay together. They should fly apart,

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00:26:30.279 --> 00:26:33.240
and that was then confirmed later in
the seventies. Nineteen seventy eight by Via

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00:26:33.799 --> 00:26:41.880
Rubin, a wonderful American astronomer.
She made that she basically put together all

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00:26:41.920 --> 00:26:45.640
these ideas to work out that the
only way you could get galaxies holding together

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00:26:47.279 --> 00:26:51.960
was if they were enveloped in a
sort of spherical cloud or halo of dark

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00:26:52.039 --> 00:26:56.440
matter. And that's been this sort
of status quo ever since. But we

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00:26:56.640 --> 00:27:03.279
now have this new research which this
takes big bad that's right, takes the

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00:27:04.079 --> 00:27:12.640
rotation idea, but looks at the
way galaxies rotate millions of light years from

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00:27:12.680 --> 00:27:19.000
their centers, in other words,
the very outer regions of galaxies. They

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00:27:19.359 --> 00:27:25.720
are basically sorry, I've just canceled
a call there from something quite famous,

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00:27:25.799 --> 00:27:36.920
interestingly said, I'll call you later. They've taken they've looked at large galaxies

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00:27:37.519 --> 00:27:41.039
and looked at the way they rotate
in their outer, outer most regions and

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00:27:41.200 --> 00:27:49.079
discover that it's it looks as though
they're still being controlled by dark matter.

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00:27:51.119 --> 00:27:55.920
So the bottom line is that they're
saying that the dark matter halos, either

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00:27:56.640 --> 00:28:00.119
the dark matter haloes are much much
bigger than we thought they were, that

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00:28:00.200 --> 00:28:03.519
these galaxies are immersed in enormous halos
of dark matter, much bigger than we

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00:28:03.759 --> 00:28:08.759
thought they were before, or we've
got it wrong, and you know that

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00:28:08.880 --> 00:28:17.720
we're we're we're we're misleading ourselves by
the fact that our understanding of gravity and

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00:28:17.880 --> 00:28:23.119
acceleration are incomplete. And this goes
back to Mordeheigh Milgram's theory of moond as

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00:28:23.160 --> 00:28:34.759
it's called modified Neutonian dynamics, that
says that very low accelerations Newtonian dynamics doesn't

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00:28:34.799 --> 00:28:37.960
work the way Newton said it did. In other words, you know,

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00:28:37.039 --> 00:28:41.200
you push something and it moves,
but it doesn't quite work that way a

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00:28:41.359 --> 00:28:47.400
very low accelerations. So that's the
that's the issue. You know, it's

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00:28:48.279 --> 00:28:56.559
it's once again, it's it's challenging
dark matter dark matter. We the mainstream

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00:28:56.759 --> 00:29:00.680
belief is that it is some form
of massive subatomic posts that we have not

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00:29:00.799 --> 00:29:04.680
yet discovered. In fact, the
sub Atomic Particle Fraternity have worked very very

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00:29:04.720 --> 00:29:10.079
hard to try and find whatever this
is, but we've failed completely. So

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00:29:11.720 --> 00:29:15.119
if it's not a particle, what
is it? And this work kind of

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00:29:15.200 --> 00:29:21.519
pushes back in the direction of our
understanding of acceleration being roll. Yeah,

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00:29:21.839 --> 00:29:27.359
I think it's w D thirty nine
what it is? Yes, well,

319
00:29:27.400 --> 00:29:34.200
there you go. It could be
could be it is. I'm hoping the

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00:29:34.319 --> 00:29:40.880
day will come where we find out
what dark matter is and the penny drops

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00:29:40.880 --> 00:29:45.480
and we go, yeah, of
course it's so simple. Yeah, yes,

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00:29:45.640 --> 00:29:48.480
we're not there. No, we're
not. And the reason why Mom

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00:29:48.720 --> 00:29:52.480
doesn't have a big following is that
it sort of lets you down in other

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00:29:52.559 --> 00:29:57.359
ways. It might explain the rotation
of galaxies, but it can't explain explain

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00:29:57.720 --> 00:30:03.799
the behavior of galaxies in cluster in
clusters, which is what old Fritz Vicki

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00:30:03.000 --> 00:30:10.279
was discovering. There are a few
other things that don't work well. In

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00:30:10.400 --> 00:30:12.160
fact, you know, to do
with the general structure of the universe,

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00:30:12.240 --> 00:30:15.960
you tend to need dark matter to
make the universe look like it does.

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00:30:17.519 --> 00:30:19.960
So the dark matter has still got
a lot a lot going for it,

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00:30:21.079 --> 00:30:25.119
Andrew, Yeah, sure has.
And of course, now that we've talked

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00:30:25.119 --> 00:30:30.559
about it, I'm sure we'll get
one or two questions and potential theories.

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00:30:30.640 --> 00:30:33.880
A lot of our audience do put
up theories, which we do like we

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00:30:34.000 --> 00:30:38.279
do. Okay, if you want
to read that story, it's at Space

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00:30:38.559 --> 00:30:44.640
Daily dot com and you'll probably find
it on many other pages as well.

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00:30:45.279 --> 00:30:48.559
That brings us to the end of
this episode. But don't forget to visit

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00:30:48.640 --> 00:30:52.200
our website, Space Nuts podcast dot
com or space nuts dot io and have

337
00:30:52.319 --> 00:30:57.640
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338
00:30:57.720 --> 00:31:02.920
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You can click on the supporter link
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the subscribe button if you haven't done
so already. That's it, Fred,

346
00:31:33.599 --> 00:31:37.200
thank you so much. Great pleasure
is always under it. Yeah, it's

347
00:31:37.759 --> 00:31:44.119
becoming quite regular, this isn't it. It's almost like we've been doing a

348
00:31:44.160 --> 00:31:49.279
fore years. Yes, yes,
yeah, all right, thanks, there's

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00:31:49.319 --> 00:31:52.440
more. Okay, thanks for it. We'll see you soon. Sounds great.

350
00:31:52.519 --> 00:31:56.680
Thanks Andrew. Fred Wat's an astronomer
at large part of the team here

351
00:31:57.000 --> 00:32:00.920
at Space Nuts and Hugh back in
the studio. He's trying to figure out

352
00:32:01.000 --> 00:32:05.880
how to use the Internet and from
me Andrew Dunkley. Always good to have

353
00:32:05.960 --> 00:32:09.319
your company. Catch you on the
very next episode of Space Nuts. By

354
00:32:09.400 --> 00:32:17.200
bye. You'll be listening to the
Space Nuts podcast available at Apple Podcasts,

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