Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #433: Marsquakes Surge & Parker Probe's Record Speed

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#433: Marsquakes Surge & Parker Probe's Record Speed · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
Hi there, thanks for joining us again. This is Space Nuts. My
0:03
name is Andrew Dunkley. Thanks for your company. Coming up, we will
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be looking at a couple of things. Mars quakes looks like they're happening at
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a faster and more furious pace than ever thought, and that's because we can
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detect them now with much more accuracy. Also, the Parker solar probe has
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made the news again. It is skimming around the Sun almost literally, but
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it's doing it at a thunderclap race a pace. And we'll also be looking
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at a super nova first scene in eleven eighty one, but now we know
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all about it, or at least more than they did back then. That's
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all coming up on this edition of Space Nuts fifteen second guidance in channel ten
0:48
nine ignition sequence Space Nuts or three two one Space Nuts. When I report
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it. Bill's good and here again to furnish us with his knowledge, or
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at least help my son move furniture because he's got a new apartment in Sydney.
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Is Professor Fred Watson, Astronoment at large, high friend. Thanks Andre,
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just let me know, and yeah, we'll be there hoping. If
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we're planning the trip down he hasn't quite got it yet all the legal stuff,
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you know, well, how to deal with that? Whereabols is it?
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What suburb is in campsy more specifically a place called Clempton Park, which
1:32
is very pretty leafy little suburb. And best of all, he's not on
1:36
a main road whatsoever, so no traffic. Very hard to do in Sydney,
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very hard to do. We're kind of we're quite proud of him because
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he's managed to do this all by himself in the second most difficult real estate
1:49
market in the world, which I think is really impressive. It is.
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So yes, ladies, he's a catch. Okay, there you go.
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Well, lad your friends note yeah, yeah, Now before we get into
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our stories, you've just come back from a little trip to South Australia where
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you took a tour group around and show them rocks and things. It must
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have been exciting. It was. It was a lot more exciting than you
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made it sound. So it was a round trip really. We started off
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in Adelaide, headed up to a Portagusta and then to Kuba Pede via Woomera,
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which is a name I've had in my vocabulary since I was about six
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because the you know, it was always in the news, was Woomera when
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I was growing up in the nineteen fifties, that this was the spaceport for
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British rocket tests and all kinds of other things, and it was all happening
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very much front of mine, very prominent in the media. But I've never
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been, Andrew never visited now and it's worth a look. Look you would
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enjoy it too. There's a lot of vintage space stuff there, reminiscent of
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I guess the Kennedy Space Center, but an earlier generation when rocketry was in
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its kind of the modern era of rocketry was in its infancy in the post
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World War II period. Lots to see some really interesting aircraft and missiles,
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rockets and all the rest of it. Is the Australia's first ever rocket still
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in that chuck shed. That's probably I didn't see it there somewhere apparently yeah,
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it will be, yeah, but of course it's still an active site.
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I think it's the OLAF that operates now. There's the Woomor Prohibited Area.
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It's a huge area of South Australia. I don't know how many thousand
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squareculus as it is, but they still do launches and people in the area,
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the station station dwellers, station halls, people have got sheep stations and
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things like that. They get to all every so often we're going to evacuate
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you for a day. So well they do. And it's very secret,
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so we'll just find out about any of that. But we did talk about
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the history and it was great. And then of course I should mention the
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reason it's called woomera is because that's a an aboriginal device to launch a speed
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it is gives it gives a spear a much greater and extra a great name,
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great name. They made some spaces too, we did. Yes,
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we followed the paths around two places like Williams Creek and Marie. Marie is
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interesting because it's got a it's got a man, the mari Mon, which
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when you see it from the air, is an Aboriginal elder probably has got
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a long beard and he's four kilometers long and nobody knows how he got there,
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but it looks as done by bulldozers or something like that. And then
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and then down to our karula of place where there's a dark SkyPark, and
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to a place called nil Pina, and in fact the Nilpina Ediacara National Park.
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Eddie Kara is the name of the hills in which some very interesting fossils
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were found some years ago, and these are the fossils of the first animals,
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basically the first things that moved around on beds of microbial mats in shallow
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seas. And we met the chief ranger there, Kim Goyer I think is
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the way his name is pronounced, who flashed his space Nuts t shirt as
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soon as as soon as we arrived, which was great. So it was
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good to see Kim and talk to him. And then a bit further on
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we met another space nutcase down on the Murray River. We were at a
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place called Manham at the time, but we had a lovely dark sky vet.
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All the locals came out and we did some talks and everybody dressed up
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in stars and spacey kind of stuff. One of our tour guests came fully
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cloud in an astronaut suit which she apparently needed a pump to keep the air
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blowing through it so he didn't die. Fantastic stuff. But there we also
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met Tracy Hill. There's another space nut and Tracy was very gracious in the
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fact that she took part in a charity auction which was to buy a copy
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of a book called wis Uranus Upside Down that had something to do with me.
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So she paid a handsome price for that, and Tracy well done.
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There was a slight mix up with Tracy's name when the winner was announced,
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so I had to rewrite the inscription in the book. But it was great
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to meet Tracy with a nice chart. And we'll stay in touch with both
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Kim and Tracy because these are people who are passionate about the district they live
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in, passionate about the things that they can show people wonderful. All right,
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Hello Kim, Hello Tracy, and thanks for being space Nuts followers.
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They're all over the world. I think you know, it would be hard
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pressed not to run into one these days, the way things are going.
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It fantastic to be like that, wouldn't it. I didn't run into any
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in China though when I was there. Yes, we've never had a question
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from China. I don't think more than welcome, more than welcome. Yeah.
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So you're back down to Earth now, so to speak, and back
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to normal for a little while. But Space Nuts continues, and we're going
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to talk about Mars quakes. Now. And this is a really interesting story
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because we have talked about Mars quakes before and they've been investigating them courtesy of
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the Insight mission. But now they're starting to come up with numbers that are
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a little bit bigger than they expected. That's correct. The the the analysis
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of this, Andrew, comes from a spacecraft that's no longer operational, our
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old friend Insight, which was fitted with a seismograph seismometers to measure mass quakes.
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And the bottom line with this story is that some of the mass quakes
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have been misinterpreted, which is easy to do when you're looking at a record
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of I guess little tremors that you know, you don't really have much of
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a clue with that tremor as to where they come from. We did talk
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about this recently actually because some people said, when you've only got one size
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bomby to how do you know where these tremors are coming from? And there's
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various signatures in the tremors that you can interpret as to what the what the
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path that these tremors have taken through through the you know, through the Martian
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crust, what that path is. So this is work that has been carried
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out by scientists at et h Jury, which you might know is the university
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that Einstein attended and Imperial College London, and I once did a course there,
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so it's a common ground for us in the world of astronomy. So
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these scientists, what they've done is they've essentially made a kind of estimate from
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the seismic data from Insight as to the global meteorite impacts, and that gives
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them a number of somewhere in the region quote between two hundred and eighty and
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three hundred and sixty meteorites striking the planet each year, forming impact craters greater
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than eight meters, which is about twenty six feet. So these are impact
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craters that you could detect from space, you know, with the various Mars
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orbiting spacecraft, and indeed they have they've managed to link and I think this
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is the crux of the matter. They've managed to link some of the seismic
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traces with what are obviously newly excavated impact craters, so that you can tell
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by the color if you're looking down from an orbiting spacecraft and you see something
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that has a particular color against the red of the Martian dust, you can
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get a clue as to whether that crater is a new one or not,
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whether that is the result of a recent impact. And in fact, I
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think they've been able to tie down some of the seismic traces with a particular
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new impact feature. And so basically what it means is that I think it's
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something like five times the number of impacts that we thought were hitting the surface
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is what is now estimated from this new new research and what the conclusion they
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come to. Actually, let me quote Geraldine zen Heisen from eh Turich who
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says the rate was about five times higher than the number estimated from orbital imagery
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alone. Aligned with orbital imagery, our findings demonstrate that seismology is an excellent
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tool for measuring impact rates. So there's that link between what you can see
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from orbit and what the seismograph is telling you. I'm fascinated by this because
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they're giving us numbers in the hundreds, but Earth gets hit to the tune
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of thousands a year and we don't seem to see those sorts of cratering effects.
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What's the difference? Is it because Mars atmosphere is so thin and yeah,
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chartistics, that's right. So you know, if Mark if we had
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the same atmosphere density as Mars two or three hundred, hate me to create
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us every year would be headline making news. Yeah, because we just sort
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of you really want to go anywhere without experiencing the risk of something hitting you
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all the head that could cause and ape me to create it. And so
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that's you know, that's the crucial part is the Mars's atmospheric pressure is point
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zero six sorry, it's point six percent. Zero point six percent of Earth's
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atmospheric pressure is less than one percent, So there's much less of a breaking
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influence by the atmosphere on Mars than there is on Earth. And by breaking
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that's br br a k i n G, not br e a k i
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n g. So what it means is that these meteorites always hit Mars's surface
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a very high velocity, what they call hYP hyper hypervelocity impacts, and it's
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that that really betrays the to orbiting spacecraft, that reveals that something's happened recently,
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because they they apparently cause a debris zone around the crater which is more
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than one hundred times bigger than the crater itself, so that they stand out
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from orbit. You've got to create maybe eight meters across, that's pretty big,
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but with something eight hundred meters you know, around it, that tells
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you that there's there's something's happened there. So actually the points made in the
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paper that they've written, knowing the number of impacts is going to be really
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important for the safety of any explore exploring spacecraft, whether they're robotic or whether
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they've got humans on board. And I suppose there'd be no pattern to this,
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so I guess if you had the time to analyze that, you might
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be able to figure out where and when these things might happen. But you
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know, yeah, it increases the risk. I mean, if this was
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Earth, our insurance policies just wouldn't be we couldn't afford them. But that's
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right, when you're talking space usitions in an environment that's hostile and we're not
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built to suit Mars's atmosphere, you'd want to collide as much data as possible
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to try and avoid these situations. I imagine, yes, So it's obviously
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something that will be taken into account in future future mission planning. It's a
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bit of a warning really that Mars is a rather more hostile environment than we
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expected at the same time, it's not it's not going to rule out Mars
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exploration, you know, I don't I think it's safe to say that we've
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had how many rovers on Mars? You know, it's probably it's probably,
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it's probably ten if you include the Chinese rovers, you include not just spirit
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an, opportunity, and curiosity and perseverance. They're the big four, But
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there were rovers before that Pathfinder was one of them. Maybe it's not ten,
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but perhaps six, seven or eight something like that. Rovers on Mars.
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None of them, as far as we know, have been zolked by
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incoming meteorite. So it's a risk, but it's a low risk, yes,
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yes, And I suppose we should also say that not all these earth
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tremors that have been picked up over the course of its mission are caused by
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meteorites, So yes, that's correct. There's been other factors as well,
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and some of them are still a bit of a mystery. Yes, So
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that's really the I guess, the pole point of their argument that they've been
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able to isolate the ones just by the characteristic signature. They've been able to
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isolate the ones that are caused by meteorites rather than by tectonic activity. There
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isn't much tectonic activity on Mars in that regard. Its core is much cooler
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than the Earth and so it doesn't drive the tectonic activity that we have.
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Okay, if you want to follow up on that story, it's been published
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in the journal Nature Astronomy. This is Space. That's Andrew Ankley here with
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Profess Fred what's an the piece MUDs. This next story is interesting too,
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fredd In that we've been hearing about, well, we've heard about this once
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before, but it's happened again. The Parker Solar Probe, which is orbiting
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the Sun and has been since oh gosh was it. It's been up there
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for five or six years, I think something like that. It's just achieved
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or equalled a speed record during one of its recent orbits. And we're talking
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numbers that are just mind blowing. I mean, tens of hundreds of thousands
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of kilometer, isn't it. It's amazing, it is. So. The
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Parker solo probe is interesting. It's one we've talked about much, but it's
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been it has been active, as you've said, for some years. It's
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just deleted its twentieth close approach to the Sun, and that's telling you that
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this is the the spacecraft that comes closest to the Sun. Of all the
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solar orbiting spacecraft that we have launched, this one is the closest, and
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in fact, its twentieth close approach was on the thirtieth of June twenty twenty
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four, not very long ago. Its distance was seven point twenty six million
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kilometers from the solar surface, and by that we mean the photosphere, the
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bit beyond which you can't see. The Sun doesn't have a surface because it's
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a ball of gas. That's about four point five one million miles, so
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it's you know, in terms of cosmic distances, that is grazing the surface
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of the Sun. It's very very close. And Kepler's laws tell us that
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the closer you get to the body that you are orbiting around, the faster
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your velocity is. Is how it works, and that's why we've got this
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record speed. In miles an hour, it's three hundred and ninety four thousand,
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seven hundred and thirty six kilometers per hour. It's six hundred and thirty
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five, two hundred and sixty six kilometers per hour, which, let me
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do it in my head, is somewhere under two hundred kilometers per second.
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I've got a calculator handed, but it's in that region. You divide it
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by three thousand, six hundred to get kilometers per hour into kilometers per second,
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So it seems in the region of two hundred. It's Yeah, that's
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a phenomenal velocity. And but that speed, you've really got to take relativity
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into account, not just because of the speed, but because of the gravitational
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potential that you're in. You know, you're in a strong gravitational field,
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and both of those things mean that Einstein's two theories of relativity, the special
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theory which is about speed, and the general theory, which is about gravity,
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those two absolutely start dominating your calculations. So really interesting stuff for all
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kinds of reasons. The park Asolo probe is fitted with heat shields that seem
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to bewithstanding the stresses and strains on the spacecraft that come from being so close
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to the Sun. And we look forward to hearing what data have been collected
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during that twentieth close approach to the Sun. Yeah, it seems to operate
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in a very complex orbittle pattern because it uses gravity assists from Venus in some
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situations. Just depends on what's available at the time, I think, but
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it would all be mapped out. But it will be doing its next pass
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on the twenty fourth of December, and they expect it will probably crack near
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seven hundred thousand kilometers an hour in that pass. And that's just unthinkable,
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isn't it That this has got to be the fastest thing ever? Yeah,
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that's well, that's right. It's you know, it's not the fastest that
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was launched, but because it's been wound up by all these gravity assists to
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push it so near the Sun. Yes, it probably is the fastest spacecraft
21:12
ever. I wonder how to survive so the environment that it's exposed to,
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I mean just the radio radiation it's bombarying it for one. But it would
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be exposed to tremendous heat, wouldn't it. Yes, that's right. So
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it's got a pretty substantial heat heat shield, which if I'm remembering correctly,
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I think it the spacecraft is turned so that when it's closest to the Sun,
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the heats the heat shield is doing all the work, and you know,
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well the spacecraft kind of behind the heat shield is faking the measurements so
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yeah, very intriguing and very very successful mission. Actually, so I think
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it's got is it four more or three more close passes to the Sun?
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I think it's three more, and actually I know it's four more. It's
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got four more close passes. So the mission is sort of coming to its
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closing phases. But we will, no doubt here more about it. We
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probably should do a nice story on the parkasolo probo sometimes down the track when
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we see some of these results. Yeah, I just found that the final
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pass will be next year, the twenty fourth fly by the Sun. So
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it's mission comes to an end in twenty twenty five. And that's how long
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it takes to sort of work its way into position to do a pass.
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Because it's going so fast, it just can't just sort of stop and go
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back. It's got to go out and do another lap around whatever it can
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do. A lap around Mercury would be involved, I imagined it. Yeah,
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it's quite extraordinary, what a fascinating mission, And yes, we should
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talk more about it when they start releasing some of the data. I guess
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who knows what they could learn. There's so much we don't know about the
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Sun, which makes it such an interesting thing, and it is the nearest
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star to our planet, so we can learn a lot about things that are
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so far away and untouchable just by observing what's right next door. Fred,
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Let's get onto our final story. This one I also find intriguing, and
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this one dates back to the year eleven eighty one when there was a super
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nova recorded, but we're only now starting to learn more about it. Yeah,
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that's right, eleven eighty one. It's a time. We often associate
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these super and over ancient super and ova explosions or observations with Chinese scientists,
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and in fact, probably the best known is the super and over of ten
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fifty four, which was observed by Chinese scientists, if I can call them
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that, there were certainly a US observers of the sky. That ten point
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fifty four super and over is what produced the crab Nebula, one of the
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most famous super and ova remnants in the sky in the northern constellation of tourists,
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the Bull. The crab Nebula is well studied, and in fact we've
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in the last few months seen some extraordinary images of it from the web Space
24:19
Telescope Gene web Space Telescope. But this one is different. The super and
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Ova of eleven eighty one was recorded. It was recorded throughout Asia, but
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mostly in Japan. Japan was, you know, again the home of people
24:37
who were very, very clever and careful skywatchers. And it's a time actually
24:47
when Japan was at war with you know, as often was the case in
24:56
past history. It seems to be still the case today, but Japan was
25:00
at war and there were records kept of that time which were put in a
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kind of it's what's described by our old friend fizz dot org, which is
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the website that's carrying this story, described as in diary format, so you
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know, it's like a journal I guess called the Azuma Kagami, I hope
25:29
pronouncing that correctly, which chronicled what was going on, the events taking place,
25:36
mostly to do with the war. This was all not very far from
25:37
modern day Tokyo. But other things, including this appearance of the new star.
25:45
They they they are called a guest stars in those ancient texts because they
25:52
are just a guest in the sky that then goes away. And indeed there
25:57
is a note here that they weren't that. This one was also observed in
26:03
China and Korea as well, and was bright enough to be quite noticeable.
26:08
It wasn't a daylight supernova, which we think the ten fifty four one was,
26:14
but was bright. It's comparable in brightness to the planet Saturn, which
26:19
is certainly noticeable. It's not the rightest of the planets, but it's up
26:23
there with the with the ones that you really do notice in the in the
26:29
night sky. Apparently it was visible for about one hundred and eighty one hundred
26:33
and eighty days and then dimmed away and was lost, and it took a
26:41
long time for modern day scientists to find it. They what's happened is that
26:52
basically using the the the you know, the text of this die record of
27:00
the supernova, the Azuma Kagami people have narrowed things down to the constellation of
27:08
Kassiopeir, which is another It's a far northern constellation in the northern sky.
27:12
We see it from certainly from the latitude where I am in Sydney. But
27:21
it so that gave me scientists enough of a clue to look for a remnant
27:27
from this explosion, and it's quite different from the remnant from the crab nebula,
27:33
which is just like a tangle of material dust gas that's that's obviously got
27:42
shock waves propelling through it in all different kinds of directions. This is something
27:48
quite different. First of all, it's visible in X rays, and what
27:52
we have is an X ray image from the XMM satellite with some infrared components
28:02
as well from an infrared spacecraft called WISE, so we're looking at this in
28:07
two different wavebands. And what we can see in the structure is it's,
28:14
first of all, it's a spherical object which has some really detailed what we
28:23
might call contours in it, where you've got things like, first of all,
28:29
in the middle, we've got the wind bubble. This is coming from
28:32
the paper about this. Then there's going outwards a wind termination shock, and
28:37
then a region of unshocked ejector that's material that's come from the explosion but hasn't
28:42
had a shock wave going through it. And then there's something called a reverse
28:45
shock and then a forward shock, and all this complexity can be sort of
28:52
seen in the X ray image and it sounds like my Golove game got forward
29:00
sharks in it. I can just see you doing a reverse shop with your
29:08
number five iron or whatever. Anyway, but that study has given enough detail
29:15
that scientists can now work out what this super and ova was, and it's
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a very rare one, something that does not normally happen. Two white dwarf
29:27
stars, now white dwarf stars are what our Sun will end up as it's
29:33
basically a thing the size of the Earth with the density with the mass of
29:37
the star, so very very dense and very hot. That's how the Sun
29:42
will end its days in a few billion years time. But two of these
29:45
objects apparently have collided, and that's what has caused this very unusual type of
29:52
super and over. A lot of the work has done has been done with
29:56
computer modeling, of course, and analyzing the observations and the rarity is this
30:04
double shock formation that we've just spoken about, the forward shot and the reverse
30:08
shock and then the inner shock. And so there is a sort of footnote
30:17
to the story though that comes from these observations. The sort of winds that
30:23
blow from this event, what we call stellar winds. They are thought to
30:29
be relatively recent in their formation, so that they say, perhaps only with
30:34
the past twenty or thirty years, these high speed stellar winds have been blowing
30:38
from the surface of the star, which is quite extraordinary really just you know,
30:42
we happen to be looking at it at the right time to see some
30:47
of the action. Yeah, indeed, And it's you know, we get
30:52
very lucky sometimes with observations. But I suppose we could also suggest that these
30:56
things are happening so regularly. Maybe it's not luck. We're just picking them
31:02
up because they're happening and at a rate of a dime. A dozen't But
31:06
this one, this one's different. This one's been quite unusual and a very
31:11
lucky discovery. Indeed, my hope Fred one day is we do get to
31:15
see one for real in our lifetime, Beetle juice being the optimum candidate.
31:21
I suppose, Yeah, that's correct. It's it's we don't want want too
31:26
close, Andrew, But yeah, Beatle, this is about battle Jos,
31:32
however you pronounce it. It's about seven hundred light years away, I think,
31:37
which is it's far enough away that we would certainly see something visible in
31:44
the daylight sky. It will be very bright, but it's not going to
31:48
be lethal to life on Earth, which a nearer one might be. Yeah.
31:53
Yeah, And in recent discussions we've talked about things that have happen been
32:00
so far away from us that have actually affected our atmosphere. So yes,
32:02
that's right. It is really mind boggling to consider that there's so much influence
32:09
out there that is so far away and we think we're all safe and well,
32:14
and we are, but you've just always got to consider the possibilities,
32:17
I guess. But yeah, that story was published in the Astrophysical Journal,
32:22
if you're interested in finding out about the SN eleven eighty one supernova. Fred,
32:30
we've reached the end of the program. Thank you so much. Well,
32:34
it's a great pleasure, and it's not a pleasure to have reached the
32:37
end, but it's always a pleasure to talk about these things. The end
32:42
is nigh. Yes'm we'll see you on the next episode. Sounds good.
32:47
Thanks very much, and we take care and we'll speak to Fred Watson,
32:52
Astronomer at Large, and thanks for listening. Don't forget to follow us on
32:55
social media or if you're on YouTube, hit the subscribe button, and don't
33:00
forget to visit our web website, Space Nuts podcast dot com. Oh,
33:05
and thanks to here in the studio who couldn't be with us today, but
33:08
all the best to his wife who's dealing with some medical issues. As we
33:14
all are when we reach this age and from me Andrew Dunkley, thanks for
33:16
your company. See you on the next episode of Space Nuts. Bye bye
33:21
Spacenuts. You'll be listening to the Space Nuts podcast available at Apple Podcasts,
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33:34
demand at bytes dot com. This has been another quality podcast production from sights
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dot com.