# How One Dinosaur-Killing Impact May Have Triggered Global Firestorms

An episode of [Space Nuts: Astronomy Insights & Cosmic Discoveries](https://invisiblenetwork.ai/podcast/1080090608), 20 Aug 2026, 44 min.

Audio: https://dts.podtrac.com/redirect.mp3/pscrb.fm/rss/p/op3.dev/e/api.spreaker.com/download/episode/74363154/how_one_dinosaur_killing_impact_may_have_triggered_global_firestorms_nordvpn_sponsor.mp3

Sponsor Link: This episode of Space Nuts is brought to you with the support of NordVPN. Secure your online presence and enjoy a special deal at www.nordvpn.com/spacenuts. Asteroid or comet, dinosaur impact firestorms, crater discovery, and Q&A on exoplanets and satellites Andrew Dunkley is joined by Professor Jonti Horner of the University of Southern Queensland for two tightly related Space Nuts conversations. The first explores how astronomy keeps blurring the lines between asteroids and comets, what new research says about the dinosaur-killing impact, and a surprising crater found by an amateur astronomer planning a trip. The second is a listener Q&A covering exotic exoplanet weather, space regulation, and whether planets can form without a star. Key topics In this episode, Andrew and Jonti explain why astronomy often uses tidy labels for objects that sit on a continuum, especially when the line between asteroid and comet gets blurry. They discuss near-Earth object 1998 SH2, which appears to have comet-like activity despite looking asteroid-like for decades. Jonti breaks down how outgassing can nudge a small body off its predicted path, revealing non-gravitational forces. The dinosaur-killing impact is revisited with new modelling suggesting the first hours after impact may have included global firestorms, not just long-term climate collapse. The show covers the terminology debate around meteor, meteorite, fireball, bolide, asteroid, and comet impact. A Canadian amateur astronomer, Joel LePointe, is credited with spotting a likely impact crater while planning a camping and hiking trip using satellite imagery. The newly identified crater near Lake Marcel in northern Quebec is described as about 390 million years old and roughly 25 kilometers wide. Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts-astronomy-insights-cosmic-discoveries--2631155/support.

## Transcript

[0:00] Andrew Dunkley: Hello again and thank you for joining us on
[0:02] another episode of Space Nuts. My name is
[0:04] Andrew Dunkley, your host. It's great to have
[0:06] your company. I hope you're well and I hope
[0:08] you can stick around. We've got some really
[0:10] great storeys today. These are fascinating.
[0:13] Remember that asteroid impact that led to the
[0:16] loss of the dinosaurs, you know, happened a
[0:18] couple of weeks ago? Uh, well, uh, it
[0:21] may have been much worse than we first
[0:23] thought. Lost lots of, uh, crispy critters as
[0:26] a consequence. We'll explain all that. Uh,
[0:28] there was a near Earth asteroid discovered
[0:31] around 30 years ago. 30 years ago. Well, now
[0:34] new evidence suggests it may
[0:37] have been a comet. And I love
[0:40] this storey. This is about a Canadian amateur
[0:43] astronomer who was planning a trip online
[0:45] using, uh, using online maps. And
[0:48] he made a massive discovery. We'll tell you
[0:51] all about it on this episode of space nuts.
[0:54] Generic: 15 seconds. Guidance is internal.
[0:56] 10, 9. Ignition
[0:59] sequence start.
[1:00] Jonti Horner: Space nuts.
[1:01] Generic: 5, 4, 2, 1, 2, 3, 4,
[1:04] Jonti Horner: 5, 5, 4, 3, 2, 1. Space
[1:07] nuts.
[1:07] Generic: Astronauts report it feels good.
[1:10] Andrew Dunkley: And joining us, uh, this time around
[1:12] with Fred Watson, gallivanting around chasing
[1:15] solar eclipses is Professor Jonty
[1:18] Horner, professor of Astrophysics at the
[1:20] University of Southern Queensland. Welcome
[1:21] back, Jonty.
[1:22] Jonti Horner: Oh, uh, thanks for having me. It's good to be
[1:24] the substitute Yorkshireman again.
[1:26] Andrew Dunkley: Yes, we've got a whole set of them.
[1:30] It's really good stuff.
[1:31] Um, now we've got some amazing
[1:34] storeys. I know you've been a very busy young
[1:37] fellow for, um. Well, since we last
[1:40] spoke to you, uh, you do your own sort of
[1:42] gallivanting, but we managed to nail you down
[1:45] for a couple of weeks, which is fantastic.
[1:48] Uh, let's get straight into it because, um,
[1:51] these storeys dovetail. Well, we've got an
[1:53] asteroid that
[1:56] may have been a comet. Then we've got an
[1:58] asteroid that hit Earth that seems, uh, to
[2:00] have done more damage than we thought. And
[2:02] then we've got a hole in the ground
[2:04] discovered while someone was planning a
[2:06] holiday. All kind of related.
[2:08] So let's get stuck into the, uh, first
[2:10] storey. A near Earth asteroid that
[2:13] was discovered 30 years ago they think might
[2:16] have been a comet.
[2:18] Jonti Horner: Yeah, this is a lovely storey and it ties
[2:21] into something that we've talked about in
[2:23] different lights previously when I've been on
[2:26] the show, and I'm sure Fred Watson spoken
[2:27] about it quite frequently as well, which is
[2:29] that, uh, very human need to break things up
[2:32] into manageable chunks, you know, so you
[2:35] go from being a child to being a teenager to
[2:37] being an adult and there's A miraculous day
[2:38] when you wake up and you're suddenly legally
[2:40] able to drive.
[2:41] Andrew Dunkley: Yes.
[2:41] Jonti Horner: And in different countries, that's a
[2:43] different debt. But we all have it. But
[2:45] fundamentally, you're not really any
[2:47] different as a person the day before that and
[2:49] the day after it. What we're doing is we're
[2:51] breaking up this kind of continuum of human
[2:53] experience into chunks, where we group things
[2:56] that are similar together and we put things
[2:58] that are more different into separate groups.
[3:00] And I've talked about this in the past when
[3:02] we've talked about the difference between
[3:04] planets and stars and that amazing middle
[3:07] ground that are brown dwarfs, where in
[3:09] effect, you've actually got objects of all
[3:12] sizes from the size of a grain of sand,
[3:14] actually from the size of a single atom or a
[3:16] single subatomic particle, all the way up to
[3:18] the biggest galaxies and beyond in this kind
[3:21] of continuum of sizes. But you go through
[3:24] kind of rock to planet to brown dwarf to
[3:26] star. And we put these arbitrary divisions in
[3:29] so that we can group things that look similar
[3:31] together and study them to make life easier.
[3:35] And we talked about that, of course, in the
[3:37] context of Pluto, with the whole thing of
[3:39] when is a planet not a planet, when it's a
[3:41] dwarf planet, and why all that happened.
[3:43] That's exactly the same kind of thing. In my
[3:45] kind of contextualization, that was the right
[3:46] decision. That's a hill I'll quite happily
[3:48] plant my flag on. But
[3:51] Pluto's like the gangly teenager. From a
[3:53] distance, it looks big and like a serious
[3:54] adult, but it's still not very good at
[3:56] tidying its room up. That's the kind of
[3:57] analogy you there. This
[4:00] whole storey is another one of those same
[4:02] things. If we had been talking
[4:05] 300 years ago, people would have been
[4:08] familiar with comets, at least the bright
[4:09] ones. You know, things that get bright enough
[4:11] to see with the naked eye that have a glowy
[4:13] coma and a tail. They appear briefly, then
[4:15] vanish forever. And we had great comets a
[4:18] couple of times in the last few years, on
[4:20] average one per decade. But it's a bit hit
[4:22] and miss. And the idea is, with modern
[4:24] scientific knowledge, what you're seeing when
[4:27] you get that phenomenon is a big dirty
[4:29] snowball or a snowy dirt ball that's whizzing
[4:31] around the sun on this hugely elongated
[4:33] orbit. When it's far from the sun and it's
[4:36] nice and cold, we just don't see it. You'd
[4:38] need the biggest telescopes on the world
[4:39] because you've just got this little thing
[4:41] reflecting a bit of sunlight. But when it
[4:44] comes near to the sun, its surface gets hot.
[4:47] The volatile material on it gets too hot to
[4:50] still be solid, so turns into gas. And
[4:53] that gas erupts from the surface, carrying
[4:55] with it dust, shrouds that snowball
[4:58] in what's called a coma, a big spherical
[5:00] cloud of gas. And then the solar wind pushes
[5:03] the gas and dust away from the sun and you
[5:04] get the tails. And so a comet, as we see
[5:07] it, is pretty big, can be millions or
[5:10] tens of kilometres, tens of millions of
[5:12] kilometres across, which is this huge amount
[5:15] of gas and dust floating around in the solar
[5:17] system, all given off by an icy,
[5:19] rocky, rubbly object only a few kilometres
[5:22] across in the head. And that's a comet. So
[5:25] it's basically something that has activity
[5:27] that out gases as it goes around the sun.
[5:29] Andrew Dunkley: Yep.
[5:31] Jonti Horner: 19. In 1801, sorry came along
[5:34] and Giuseppe Piazzi found Ceres, which
[5:37] was an object between the orbits of Mars and
[5:39] Jupiter. And he found it because they were
[5:41] looking for a planet, because people had
[5:43] suggested that might just be that there's a
[5:46] planet between Mars and Jupiter. So the
[5:47] celestial police were looking, but Piazzi got
[5:50] there first and that was the first of the
[5:51] asteroids. And over the decades, and
[5:54] the couple of centuries that followed, one
[5:56] object became four, became tens,
[5:59] became hundreds, became thousands, and
[6:02] nowadays it's over a million. And if we
[6:04] were talking kind of 30 or 40 years ago, we'd
[6:07] have had a very clear idea of what an
[6:09] asteroid is and that an asteroid is very
[6:12] different to a comet. So an asteroid is a
[6:14] rocky or metallic object that
[6:17] even when it gets near the sun, just stays as
[6:19] a rocky metallic object. No gas comes off it,
[6:21] just a lump of rock or rubble going around
[6:23] the sun. So
[6:26] rocky, rubbly object, icy object with loads
[6:28] of gas. You've got a comet, you've got an
[6:30] asteroid, very distinct.
[6:33] Now, water's got a bit more muddied for
[6:36] a few reasons over the last few decades.
[6:38] Firstly, you had objects called the
[6:41] Centaurs, which I studied for my PhD, that
[6:44] are big icy objects that are too far away
[6:46] from the sun most of the time to outgas. So
[6:49] got kind of asteroidal classifications and a
[6:51] couple of them got a bit nearer in and
[6:53] started out gassing, so got a dual classific.
[6:57] Chiron is the most famous. Chiron has both an
[6:59] asteroidal classification and, um, a cometary
[7:01] classification. Cause sometimes it looks like
[7:03] an asteroid, sometimes it looks like a comet.
[7:06] You then have things like the Geminid meteor
[7:08] shower every December, which is our best
[7:10] meteor shower. I love it dearly. Almost
[7:13] all of the meteor showers are produced by
[7:15] comets and we get them when we go through the
[7:17] dust that has been left behind by the
[7:18] activity of the comet when it was out
[7:20] gassing. But when they found the parent of
[7:22] the Geminids, it doesn't look like a comet,
[7:25] it's an asteroid. So the idea became that
[7:28] maybe it's a rock comet and it's getting so
[7:29] close to the sun it's shedding dust and we
[7:32] get the meteor shower. Then there were
[7:35] a couple of comets that were lost. And then
[7:38] many, many decades later, an asteroid was
[7:40] found that looked to be moving on the same
[7:42] orbit as a comet. And so maybe they're the
[7:44] same object and the comet has turned off. And
[7:47] when the comet has turned off and stopped
[7:48] making any gas, maybe it looks like an
[7:51] asteroid. So there's this blurring going on.
[7:55] In reality, what you've got is a
[7:57] continuum from rocky and metallic and nothing
[8:00] else on one end to incredibly icy on the
[8:02] other, and everything in between where you
[8:04] have more rock, less ice, more ice, less rock
[8:07] blurring together. That's a
[8:10] hell of a lengthy introduction, hell of a lot
[8:12] of background to give the context for this
[8:14] storey. So, in light of all that, back in
[8:17] 1998 there was this near Earth
[8:20] asteroid discovered. It goes by the of 1998
[8:23] SH2 and it looks like a lump of rock.
[8:25] It goes around the sun every four or five
[8:27] years, whizzing around. It's been seen at a
[8:30] few apparitions since. And, um, that's all
[8:33] well and good. We know a few thousand Near
[8:35] Earth asteroids now and we're finding more
[8:37] and more of them all the time. And people are
[8:39] particularly interested because, of course,
[8:40] if they come near the Earth, there's a
[8:42] possibility that eventually one of them will
[8:44] come too near the Earth and will hit us and
[8:46] we'll have issues. And ask the dinosaurs
[8:49] about that. We can come back to that a little
[8:50] bit later on. So there's a lot of interest in
[8:53] learning more about near Earth asteroids and
[8:56] following them because the longer you observe
[8:57] them, the more accurately you know how
[8:59] they're moving. So the better you can predict
[9:01] into the future where they'll be and
[9:04] therefore rule out the chance of that object
[9:06] hitting the Earth. Uh, may also, of course,
[9:09] be interesting to people who want to mine
[9:10] that object in the future with off Earth
[9:12] mining that if you want to go mine it, you
[9:14] need to know where it is. Yeah, so
[9:17] that's this object. Brilliant. We found an
[9:20] Earth asteroid.
[9:21] Where it gets interesting for this storey
[9:24] is that, uh, back in August 2025,
[9:27] which is what, 27 years after this thing was
[9:29] discovered it had another close approach
[9:32] to Earth. Now, this wasn't like the
[9:35] forthcoming approach for the asteroid
[9:37] Apophis, which is going to come closer to us
[9:39] than geostationary satellites. This was close
[9:42] to astronomers and distant to everybody else.
[9:44] You're talking about the thing coming about 3
[9:46] million kilometres away at its closest
[9:48] approach. Now, that's relatively close, but
[9:51] it's not something to get particularly
[9:53] panicked about. That's nearly 10 times as far
[9:55] away as the moon is, about 8 times as far
[9:57] away as the Moon is. But it's near enough
[10:00] that if you want to learn more about the
[10:01] asteroid, what you can do is you can get the
[10:03] planetary radar, uh, that they used to beam
[10:06] radar, uh, out into space and bounce it off
[10:08] things and get it back. Yeah, to try and
[10:10] bounce radar, uh, off this asteroid
[10:13] to get an image of what its shape is, to
[10:15] learn about its rotation and figure out how
[10:17] big it is. Because even with the biggest
[10:20] telescopes on the planet, something like this
[10:23] is always just a single pixel. You can't zoom
[10:26] in. So what they did was they got the
[10:28] planetary radar, uh, sent radar out to this
[10:31] object and missed
[10:34] a little bit. Embarrassing as you do, it
[10:37] wasn't quite where it was supposed to be.
[10:40] So based on all those historical
[10:41] observations, you can predict into the future
[10:44] where the asteroid will be based purely on
[10:47] the gravity of all the planets. It's getting
[10:49] pulled around by the Earth, uh, and Venus,
[10:51] Jupiter, everything's pulling and tugging on
[10:53] it. And you can in a very prescriptive way
[10:56] run its orbit forward in time and say where
[10:57] it will be in the future if the only thing
[11:00] acting on it is gravity.
[11:03] But it wasn't where it should be. Uh, the
[11:06] fact it wasn't where it should be says
[11:08] something else is happening as well.
[11:10] Something else is happening to push it around
[11:12] now. So at this point, sometimes that we get
[11:14] the, oh, well, it must be an alien spaceship
[11:17] thing happening. That's exactly what's
[11:19] happened in the past with people suggesting
[11:21] there's maybe something more going on that
[11:24] actually hasn't happened with this one, which
[11:26] is really nice to see. But what
[11:28] that being out of position tells you is that
[11:31] there are non gravitational forces acting on
[11:33] this thing. Something other than gravity is
[11:36] happening to push it around a little bit.
[11:39] Now, M. If we rewind to comets for a little
[11:41] bit. I remember when I was a teenager back in
[11:43] the early 1990s, we had Comet Swift Tuttle
[11:46] came past and, um, Comet Swift Tuttle's a
[11:48] parent of the Perseid shower. And, um, that
[11:51] was kind of a relief because at, uh, Its
[11:52] previous apparition, Comet Swift Tuttle, had
[11:54] been seen widely observed and had been
[11:57] predicted that it would come back in about
[11:59] 120 years. It would come back in the early
[12:01] 1980s and it didn't show up.
[12:04] M which was a bit weird because this is a
[12:06] bigger and more active comet than Comet
[12:08] Hallie. It's probably the biggest of the
[12:10] comets with a period less than 200 years.
[12:12] Pretty epic object. And it came back 10
[12:15] years later. Now, by the time it came back,
[12:17] people had figured out kind of what was going
[12:18] on, had realised that it was going to be
[12:21] late. But part of the complexity there
[12:24] was that, uh, because this is quite an active
[12:25] comet, when it's ejecting gas and dust to
[12:28] space, that process acts like a
[12:31] rocket engine that pushes it around. So it's
[12:33] ejecting gas in one direction and that exerts
[12:36] a force pushing the nucleus in another.
[12:38] And that is not a predictable thing in
[12:41] that every time a comet comes around the sun,
[12:44] its rotation will be a bit different. Some
[12:46] active areas will turn off and some will turn
[12:48] on. So while you can get a general trend and
[12:51] you can make loose predictions, there's
[12:53] always going to be a bit of uncertainty in
[12:55] where a comet will be in the future because
[12:57] it's got these forces pushing and nudging it
[12:59] around. You know, it's a bit like, I don't
[13:02] know if you could strap a few fireworks to a
[13:04] snowball and throw it up in the air. That's
[13:05] probably not very healthy to do. But you get
[13:07] the same kind of thing, they go off at
[13:08] different times and be pushed around all over
[13:11] the place. Um, interestingly, Comet Encke,
[13:13] which is a comet with the shortest non
[13:15] orbital period, has been seen every three and
[13:18] a half years, 3.3 years for more than 200
[13:20] years. And we've actually seen its orbital
[13:22] period get shorter and then get longer again
[13:24] as a direct result of the jets on its
[13:26] surface, uh, pushing it around and those jets
[13:29] changing the rotation direction of the
[13:32] comet. Loads of cool stuff there.
[13:36] So with that knowledge, you can look at this
[13:39] object, 1998 SH2.
[13:41] It's not where it's supposed to be. So that
[13:44] suggests that there's non gravitational
[13:45] forces happening. But whenever people have
[13:48] observed it in the past, it has looked inert.
[13:50] Uh, it's looked like an asteroid.
[13:53] What that suggests is that it is active.
[13:56] It's got some outgassing happening, but at
[13:58] such low levels that it wasn't possible to
[14:01] detect them before. So that was a clue
[14:04] that seems a really likely storey.
[14:06] So scientists go away and they do a couple of
[14:08] things. Firstly, they look for pre discovery
[14:11] observations of this, you know, times when
[14:13] there was a photographic plate made 50 years
[14:16] ago that just happened to have the object in
[14:17] the field of view so you can get a longer
[14:20] period of knowledge of how it's moved.
[14:22] Andrew Dunkley: Yeah.
[14:23] Jonti Horner: And um, with these really accurate
[14:25] observations, you can tell that it has been
[14:27] misbehaving for a long time. It's getting
[14:29] pushed and nudged around. What then
[14:32] happened was they used some of the really
[14:34] biggest telescopes in the world to take a
[14:36] look at it and detect just a tiny hint of gas
[14:39] being emitted, tiny little wisp.
[14:42] And so you put all that together and um, this
[14:44] thing is probably, of all the comets we know
[14:46] in the solar system, the least active that we
[14:49] currently know of. But it is exhibiting
[14:51] cometary behaviour. So it's another object
[14:54] really straddling the boundary. And it's
[14:56] fascinating. It'll be wonderful to learn more
[14:58] about it. But it's fascinating too,
[15:02] because here's the thing that looks like an
[15:04] asteroid, sounds like an asteroid. It does
[15:06] everything you'd expect an asteroid to do,
[15:08] except it's wibbling and misbehaving a bit.
[15:10] Now, if you're finding hundreds and thousands
[15:13] of near Earth asteroids and you want to know
[15:14] whether the Earth's safe, well, if you see
[15:17] something that's an asteroid, you can predict
[15:19] where it is with gravity going forward, the
[15:22] Earth's safe. What this is telling you is
[15:24] that, uh, gravity may not be enough. So you
[15:27] can't just say, well, it looks like it'll be
[15:28] safe, we'll stop looking. Because if this
[15:31] object's unpredictable, what about all the
[15:33] other ones we're finding too?
[15:34] Andrew Dunkley: I was about to bring that up. There's got to
[15:36] be more than one.
[15:38] Jonti Horner: Oh, absolutely. Um, we found
[15:41] quite a few of these over the years now in
[15:43] various circumstances. My favourite
[15:46] really is the Taurid stream of debris. We get
[15:48] the Taurid meteor shower every year from
[15:50] about September to December. We've got the
[15:52] northern and southern Taurids. We also get a
[15:54] daytime meteor shower in June called the Beta
[15:57] Taurids. Result is we spend about
[15:59] four months of every 12 passing
[16:02] through this enormous broad swath of debris
[16:05] where on any given night, when the meteor
[16:07] shower is active even at its peak ulcely,
[16:09] four or five meteors an hour, the debris is
[16:12] very spread out. But because the Earth spends
[16:14] so long going through it, we get more debris
[16:16] from that stream than all other meteor
[16:18] showers combined over the course of a year.
[16:22] At the core of that is Comet Encke, which is
[16:25] that comet with a 3.3 year period, but
[16:27] also a huge amount of other rubble and
[16:30] debris. There's lots and lots of asteroids or
[16:33] things that behave like asteroids moving
[16:35] around in the storage stream. And the idea is
[16:37] that this was a, uh, mega comet 20 or
[16:40] 30,000 years ago that fell apart,
[16:43] giving us this stream of debris. Comet Encke
[16:46] was probably behaving like an asteroid if
[16:48] he'd found it a thousand years ago. But
[16:50] something happened 250 years ago to wake it
[16:53] up and it started behaving like a comet and
[16:55] we see it as a comet. And the other asteroids
[16:58] in that stream are currently dormant and
[17:01] there's a load of them. So it's likely in the
[17:03] inner solar system that even just in the
[17:06] Taurid Stream, you're going to have hundreds,
[17:08] if not thousands of objects just like
[17:10] 1998 SH2 that straddle
[17:13] that boundary between the comet and the
[17:15] asteroid.
[17:18] Andrew Dunkley: Fair enough. And, uh, as a consequence of
[17:20] that, they've had to rename it.
[17:23] Jonti Horner: Yep. So it now has a cometary classification
[17:26] as well. What happens with comets is you
[17:29] get. When people find a comet,
[17:32] um, it's C, slash, then the year,
[17:35] ah, and then a catalogue number. So basically
[17:37] every comet gets a unique identifier. So we
[17:39] remember Chuchinshan Atlas, which,
[17:42] um. I'm trying to remember the correct ID for
[17:45] it, but it was, I think it was like 2023
[17:47] A, ah, 1 or something like that, A3. So
[17:50] the A means that it's discovered in the first
[17:52] fortnight of the year. 3 is the third object
[17:54] found in the first fortnight of the year.
[17:56] That tells you about the comet and then
[17:59] it's named after the discoverer in brackets.
[18:02] If the comet is seen at more than one
[18:04] apparition, the C gets changed to a P to show
[18:06] that it's periodic. In this
[18:09] case, because this already has
[18:12] an asteroidal name by which
[18:15] it's known, it's kept that, but they've added
[18:17] a P in front of it. So it's gone from being
[18:19] 1998 SH2 to being
[18:22] P. 1998 SH2,
[18:25] um, will be interesting to see whether down
[18:28] the line they add the name of the discovery
[18:29] facility to it. Um, that wouldn't surprise
[18:32] me. That's been done for previous occasions
[18:34] where we've had an asteroid that became a
[18:36] comet. But it'll be interesting to see. But
[18:38] it's. I guess what I love about this is
[18:41] you get into the nitty gritty of it, but it's
[18:43] that reminder of the beautiful complexity
[18:45] we've got. There's so much more to learn.
[18:48] Andrew Dunkley: Absolutely, yes. Uh, it's a really good
[18:50] storey and, um, one worth reading up. You can
[18:53] do that@space.com or you can
[18:55] read the published findings in the journal
[18:58] Nature Astronomy. This is Space Nuts with
[19:01] Andrew Dunkley and Professor John T Horner.
[19:06] Jonti Horner: The crew of Artemis 2 now bound for the moon.
[19:09] Generic: Humanity's next great voyage begins.
[19:12] Jonti Horner: Space note Nuts.
[19:13] Andrew Dunkley: Let's move from a comet flying through
[19:16] space to a comet, uh, or an asteroid in this
[19:19] case, that stopped, uh, flying through space
[19:22] because a big planet called Earth got in the
[19:24] way. And the one
[19:27] that, um, is referred to as, uh,
[19:30] or creating the Chicxulub crater
[19:33] in what is now known, uh, as the Gulf of
[19:35] Mexico. Uh, and we even know the
[19:38] exact impact point because they've been down
[19:40] there and taken samples, uh, which was a very
[19:43] exciting storey when we covered that sometime
[19:45] back. But now they've taken another look at
[19:47] this, uh, and gone back to the very moment of
[19:50] impact and the few hours afterwards and
[19:53] decided by the look of it that this thing was
[19:56] much more brutal than
[19:59] we first envisaged.
[20:02] Jonti Horner: Absolutely. And this kind of ties in with the
[20:04] storeys that were told again. Back when I was
[20:06] a teenager, I remember hearing about the
[20:10] impact that killed the dinosaurs and storeys
[20:12] about what would have happened on the other
[20:14] side of the planet and the idea of firestorms
[20:17] and, you know, it was a hellish experience
[20:18] worldwide. But the way you'd normally hear
[20:21] this storey relatively recently is you had
[20:23] the impact. Things were bad in the vicinity
[20:26] of the impact. Shockwaves went out, tsunamis
[20:28] went out. So over a very large area, it was
[20:30] immediately fairly devastating. But
[20:33] there was a huge amount of dust and debris
[20:35] flung into the Earth's atmosphere, which led
[20:38] to this prolonged nuclear winter type event.
[20:40] You know, it blocked the sun, got really
[20:42] cold, the plants died, the animals died. Then
[20:45] when the clouds cleared, it got really,
[20:47] really nasty because you got this period of
[20:49] runaway global warming and hideous acid rain
[20:51] because the impact had hit rocks that were
[20:53] packed with carbon and sulphur
[20:56] carbonate and sulphate rocks, which led to,
[20:58] uh, carbonic and sulfuric acid
[21:01] rain. It led to an atmosphere super loaded
[21:04] with greenhouse gases. So it basically
[21:06] made the planet fairly hellish for a few tens
[21:09] of thousands of years, from one stage to the
[21:11] next to the next. But when I was
[21:14] younger, there were these storeys about while
[21:16] there were probably global firestorms. The
[21:18] idea that an impact halfway around the world
[21:21] could set fire to forests elsewhere.
[21:24] And in recent years I've not heard
[21:27] that storey told so much. It's kind of fallen
[21:29] a little bit out of fashion. But the new
[21:31] research that's been done here is kind of
[21:34] bringing that idea back into the picture.
[21:37] Now, the idea here is that you get this
[21:40] impactor that was probably about 10
[21:41] kilometres across, smacking into the Yukon
[21:44] Peninsula, creating a crater that was
[21:47] two to 300 kilometres in diameter.
[21:50] In doing that, it would have flung a huge
[21:51] amount of rocky material, vaporised material,
[21:55] out of the atmosphere. And a lot of that
[21:57] material would have travelled at speeds
[21:59] slower than the Earth's escape velocity to
[22:01] rain back down into the atmosphere. And when
[22:03] that material falls back into the atmosphere,
[22:05] it's travelling at speeds of kilometres per
[22:07] second, so it ablates like a
[22:10] fireball that we see in the sky, like a
[22:11] meteor. But you're not seeing one or two,
[22:13] you're seeing a huge deluge of material
[22:15] raining down all across the planet.
[22:18] Now, when these bits of material hit
[22:21] the atmosphere and ablate, what they're doing
[22:23] is they're taking the kinetic energy of their
[22:25] Martian and emitting, turning it into heat
[22:28] and light, which, you know, if you get a
[22:30] single small meteor, you're not gonna get
[22:32] sunburn from it. If you get something the
[22:35] size of the Chelyabinsk impact, people
[22:36] actually did get sunburn, um, from that, from
[22:38] the brightness of the flash. Now imagine,
[22:41] instead of having one Chelyabinsk impact,
[22:43] having this rain of material falling into the
[22:45] atmosphere all across the planet, creating
[22:48] this, what's described as a thermal pulse
[22:51] that has been discussed and
[22:54] previous models, things that have come out,
[22:56] suggested that that effect would have been
[22:58] like putting a grill on. It would have been
[23:01] really quite unpleasant for thin skinned
[23:03] animals that were exposed to it. You'd have
[23:04] got burned, you might even have got killed.
[23:07] But if you were, uh, underground or you were
[23:09] underwater, you'd have been able to live
[23:12] through it. I mean, you'd have lived to see
[23:14] all the other horrors that were coming from
[23:16] the impacts. It wasn't really a good news,
[23:17] Storey, but you'd have probably survived it.
[23:20] But the argument had been that that thermal
[23:22] pulse from that material coming into the
[23:24] atmosphere would not have got things hot
[23:26] enough to ignite things like grasses. You
[23:29] know, the tinder that you get that can start
[23:32] forest fires and things like this, which I
[23:34] think is why that idea of the global
[23:36] firestorms had gone away. What
[23:39] the new research has done is looking at
[23:41] fossil sites in North America, which must be
[23:43] remembered, was quite close to the impact,
[23:46] relatively speaking, on a global sense. They
[23:48] found this layer of spherules of material,
[23:51] which is a debris that rained back down to
[23:53] Earth, uh, in the fossil record and above it
[23:56] there's this very thin layer of silicate
[23:59] dust which must have fallen out at about the
[24:01] same time. Now the
[24:04] idea is that that silicate dust
[24:07] would have effectively acted like a bit of a
[24:09] doona with that raining down and that in the
[24:11] atmosphere. The fact that it's fallen in the
[24:14] fossil record above the spherules
[24:17] means the spherules got to the ground before
[24:19] the dust got to the ground, effectively. So
[24:22] the researchers have said, well, what would
[24:24] happen if you had all this dust, all this
[24:25] silicate dust in the atmosphere and you had
[24:28] these ferrules running through, giving off
[24:30] all this heat? And it's effectively like that
[24:33] dust in the atmosphere would have acted a bit
[24:36] like a reflecting, uh, blanket or something
[24:38] like that. It would have trapped even more of
[24:40] the heat in the atmosphere and reflected it
[24:42] back down at the ground. And, um, the
[24:44] calculations that they've made suggest that
[24:47] that extra energy, because of the energy
[24:49] being re radiated back down to the ground,
[24:51] rather than escaping to space, would have
[24:54] made things hot enough for grass to catch
[24:56] fire, for pine cones to catch fire. Not
[24:58] enough not for an entire tree to burst into
[25:01] flames, but for all the tinder that was lying
[25:03] on the ground to be called a flame.
[25:06] And if that happens, what you do is you
[25:08] trigger global firestorms. So you
[25:11] turn a situation and you make it much, much
[25:13] worse. Now, what should be said
[25:16] here is this, uh, work is looking at North
[25:19] America and it strikes me that further
[25:22] away from the impact site, you probably
[25:23] wouldn't have got the impact dust. So it
[25:25] might well be that you actually had a
[25:26] gradiated kind of level of nastiness from the
[25:29] impact. So nearby it brutal. And
[25:32] then you had the tsunamis and stuff washing
[25:33] out on the far side of the planet. You
[25:36] probably didn't get the silicate dust, so you
[25:38] just got the normal level of hellishness
[25:40] where you didn't set off firestorms, but
[25:42] things were nasty. But there was probably
[25:44] this sweet spot like the ultimately bad
[25:47] porridge in the Cinderella Storey, where
[25:49] things were ultimately worse, ultimately
[25:52] as bad as they could be, where the impact
[25:55] way over the horizon, way in the distance,
[25:58] was enough to trigger forests to burst into
[26:00] flame because of igniting the tinder enough
[26:02] to cook animals alive as they were on the
[26:05] surface. Uh, really kind of brutal and
[26:08] remarkably horrific imagery.
[26:11] But it's fascinating work and m it's another
[26:14] insight into just how bad impacts like this
[26:16] could be. It's that whole thing that we're
[26:18] playing with a detective storey that is 66
[26:21] million years old and we're trying to piece
[26:23] together the narrative of what happened and
[26:26] every bit of information we get like this
[26:27] just seems to make a more and more horrific
[26:29] piece picture.
[26:30] Andrew Dunkley: Yeah, I mean, the original consensus was
[26:33] the, um, asteroid hit
[26:36] the planet and, uh, it
[26:39] created, um, tsunamis that went around the
[26:41] world, um, three, four times, something like
[26:43] that. Um, and uh, created
[26:47] the equivalent of a nuclear winter and
[26:49] everything died and there was no food and,
[26:52] uh, the creatures died along with it over a
[26:55] period of time. But this is suggesting that a
[26:58] lot of, um, the initial death,
[27:01] uh, due to these firestorms happened in a few
[27:03] mere hours. Um, it's a
[27:06] horrifying thought.
[27:08] Jonti Horner: It is. And I mean, you start getting to that
[27:10] kind of philosophical side of thing is does
[27:12] this make it better or does it make it worse?
[27:14] You know, if you were there at the time,
[27:15] would you rather be broiled and baked and
[27:17] cooked quickly or left to starve slowly in
[27:20] the cold that followed it? Yeah, I mean it's
[27:23] all fairly bleak, but it is also that
[27:25] reminder drawing just a bit like we were
[27:27] talking about in the previous storey. We are
[27:28] in the crosshairs. This will happen again.
[27:30] It's not like the Earth has been hit for the
[27:32] last time unless we do something about
[27:35] it. And it's great that we have the capacity
[27:38] to discover objects further and further
[27:40] from the Earth with a greater and greater
[27:42] lead time before they come close to us. It's
[27:44] great that we're learning the capacity to
[27:46] deflect them. But it's sometimes hard to
[27:49] justify to people why people are doing this
[27:51] kind of research. And it's one of the
[27:53] arguments we have, for example, against the
[27:55] satellite megalithic constellations, because
[27:57] we're finally a spec that can look out at the
[27:59] cosmos and detect threats. And what we're
[28:02] doing is we're throwing tinsel in the way and
[28:04] hiding the view.
[28:06] Andrew Dunkley: And that is a bit of a worry. Well, it's a
[28:08] big worry and it's not getting any better. In
[28:10] fact, it's going to get worse. We'll um,
[28:13] probably discuss that more in our next
[28:15] episode.
[28:15] But, um, I did notice
[28:18] in sort of looking at this storey that, uh,
[28:21] some papers or some websites refer to
[28:24] it as a meteorite impact rather than an
[28:26] asteroid. Why would they do that?
[28:28] Jonti Horner: This is interesting with terminology and
[28:31] I'm less uncomfortable with the idea of
[28:34] meteorite impact, asteroid impact being
[28:37] a conflation. The terminology of
[28:39] objects is a weird one and
[28:42] astronomers have very specific terminology
[28:46] that then gets a little bit confused when you
[28:48] see popular science and you see the news and
[28:50] all the rest of it when something's floating
[28:53] around in space nowhere near the Earth,
[28:56] we refer to it as a meteoroid
[28:59] or an asteroid or comet, basically.
[29:02] Um, and we talked about asteroids and comets
[29:04] earlier on and where the line blurs there.
[29:07] The typical boundary between
[29:09] calling a meteoroid and an asteroid is
[29:12] often taken as being about one metre in size,
[29:15] but that's just fairly arbitrary.
[29:18] When something enters the atmosphere and it's
[29:21] pushing the air in front of it and it's
[29:22] glowing in the sky, that phenomenon we call
[29:25] a meteor, if it's really bright, we call it
[29:28] a fireball. And that boundary is set roughly
[29:30] as bright as a planet Venus. If we see an
[29:32] explosion at the end, we call it a bolide.
[29:34] And that just means exploding fireball,
[29:36] basically. So meteor, bolide,
[29:39] fireball are uh, atmospheric phenomena.
[29:42] You're not actually seeing the thing coming
[29:43] through the atmosphere, you're seeing the gas
[29:46] that it's heated up and excited in the
[29:48] atmosphere. That's what you're seeing as a
[29:50] glow. When it reaches the ground and hits the
[29:53] ground, you call it a meteorite. That's the
[29:55] physical object on the ground or hitting the
[29:58] ground. Now, whether
[30:01] you call something like this a meteorite
[30:04] impact or an asteroid impact, I think it's
[30:05] probably both. You know, technically the
[30:08] asteroid hits the ground, um, you
[30:11] could call it a meteorite. But maybe what you
[30:13] should do is have that idea in your head of
[30:15] if it's less than a metre across, you could
[30:17] call it a meteorite. Bigger than that, you'd
[30:19] call it an asteroid. I've never seen
[30:21] clarification on where that
[30:24] boundary comes because terms are used in
[30:26] different sensors kind of thing. So for me,
[30:29] I don't think it's unreasonable to say
[30:31] meteorite impact here, although you're
[30:32] probably pushing the size definition.
[30:36] Call it an asteroid or comet impact is
[30:38] probably more reasonable. And it might be
[30:40] that if you dug into the physics of it and
[30:42] you were to do an IAU resolution a bit like
[30:44] we did with Pluto, maybe what you do is look
[30:47] at it in terms of the effect of the
[30:49] atmosphere on the object coming in. So
[30:52] things that create fireballs and bolides in
[30:54] day to day life, the atmosphere is much
[30:57] bigger in size than the object coming in,
[31:00] which means wind resistance will eventually
[31:02] slow it down. So the meteorite that we talked
[31:05] about a few months ago that landed on
[31:06] someone's driveway in Canada was travelling
[31:09] at about the same speed that a rock dropped
[31:11] out of an aircraft would have done. It was at
[31:12] terminal velocity. Its speed was
[31:15] governed by the atmosphere. Whereas with
[31:18] things that are kilometre scale, the
[31:20] Atmosphere is essentially not there. It's not
[31:22] going to slow them down. And so I wonder
[31:25] whether there is an argument that you could
[31:26] set up a definition that said if it's
[31:29] travelling at uh, speed less than
[31:31] supersonic, you'd call it a meteorite impact.
[31:34] If it's travelling faster than that, maybe
[31:36] you'd call it an asteroid impact. But I don't
[31:38] think that there's any official delineation
[31:40] like that. That's just kind of how I think
[31:43] about things in my own head.
[31:44] Andrew Dunkley: No, I like that that works. Well, well,
[31:46] that's probably a good way to think about it.
[31:49] Um, another interesting storey that uh, the
[31:52] asteroid impact uh, that killed the dinosaurs
[31:55] was a lot more damaging in the early stages
[31:57] than we first thought by the look of. But uh,
[32:00] plenty of, plenty of websites and news
[32:02] platforms have picked this one up, not
[32:04] surprisingly. Uh, but you can read
[32:07] at uh, the Science
[32:10] Advances, uh, website published in
[32:13] Science Advances. Uh, this is Space Nuts
[32:15] Andrew Dunkley here with Johnty Horner.
[32:20] Jonti Horner: 0G and I feel fine.
[32:22] Andrew Dunkley: Space Nuts, the storey. Jonty
[32:25] takes us to Canadia and
[32:27] this is a storey, uh, about a
[32:30] Canadian amateur astronomer who
[32:33] decided to plan a holiday using online maps.
[32:36] It is.
[32:36] Jonti Horner: This is lovely. I think we've all done this
[32:38] to some degree. You planning your holiday,
[32:41] planning your road trip. I just had a lovely
[32:42] holiday with the in laws. And you look at uh,
[32:45] the online maps of your choice that typically
[32:47] have really nice satellite images of the
[32:49] places you're um, and you try and figure out
[32:52] what you're going to see, what you're going
[32:53] to go there. And to some degree you sat
[32:55] browsing around thinking, I wonder if I can
[32:57] see anything unusual, what's it like around
[32:59] there? And that's what happened
[33:02] here. We've got this amateur astronomer going
[33:05] by the name of Joel Lapointe who back in
[33:08] 2024 was planning his hiking and
[33:10] camping trip. And I think it's in northern
[33:13] Quebec. It's near a place called Lake Mars.
[33:17] And he found this unusual looking
[33:20] feature next to that lake. Looks a bit odd
[33:23] on the maps on the satellite imaging. Now
[33:26] there is a university in Canada that has a
[33:29] website called Impact Earth that allows
[33:31] people to, as a kind of popular
[33:34] um, collaborative endeavour for
[33:36] citizen science is the word I'm looking for
[33:39] to log things where people think they've
[33:42] found impact features. So being an
[33:45] amateur astronomer being aware of this, he
[33:46] logged it. I think I found a crater. About
[33:49] a year later, um, the site
[33:52] as a result of this report was
[33:55] explored, visited by a planetary geologist
[33:57] from the university called Gordon Ozinski.
[34:00] Who went there, took a lot of samples,
[34:03] explored around and confirmed that
[34:06] this really is an impact feature. It's an
[34:07] impact crater about
[34:10] 390 million years old,
[34:12] so way older than the impact that killed the
[34:14] dinosaurs. About 25 kilometres
[34:17] across, which includes a load of
[34:20] incredibly well preserved features in terms
[34:23] of glassy hardened volcanic type rocks from
[34:26] the impact that he himself has said he's
[34:29] surprised at that well preserved, given how
[34:30] old it is and how far north this is, how cold
[34:33] the weather gets in the winter and stuff. Now
[34:36] this makes it the biggest crater found on
[34:38] Earth since 2018, when there was a crater
[34:40] discovered under the Greenland ice sheet. But
[34:43] the difference is that the one under the
[34:45] Greenland ice sheet is below a kilometre's
[34:47] depth of ice. So it isn't like we can get
[34:50] there and learn much more about it. That's
[34:51] still quite a mysterious spot.
[34:54] Whereas this is open and exposed and
[34:56] accessible, so people are able to go there
[34:59] and explore it, learn a lot about it. There's
[35:02] some really nice imagery out there on the
[35:05] Internet about this. From the maps, images
[35:07] where it was found to images of
[35:10] features called shatter cones, which are the
[35:12] kind of thing created that are very typical
[35:15] of an impact crater formed under very high
[35:17] pressure, very high temperature molten rock.
[35:20] So it is absolutely amazing.
[35:23] But it's also to me kind of breathtaking that
[35:26] here is a feature 25 kilometres in diameter
[35:29] in the middle of a built up, well, not that
[35:32] built up country, but in the middle of a
[35:34] country near a famous lake, there is an
[35:37] impact crater that had never been identified
[35:39] until now. You know, we're still discovering
[35:43] kilometres, tens of kilometre scale features
[35:45] on the Earth. I mean, that's just
[35:47] astonishing.
[35:50] Andrew Dunkley: Uh, yeah, it is. And um, I
[35:53] think we've talked about it in the past that
[35:56] one of the problems with finding these things
[35:58] on Earth is the fact that the Earth's kind
[36:00] of covered up with vegetation and uh,
[36:03] you know, lots of, um, weather, uh,
[36:06] activity which has caused erosion and then
[36:08] we've got earthquakes that have caused
[36:10] mountain ranges to pop up here and there. And
[36:12] so a lot of these impact points get uh,
[36:15] disturbed or are hidden. Not uncommon
[36:18] now.
[36:20] Jonti Horner: Absolutely. And I mean 70% of the Earth's
[36:22] surface is water and you need to be a bigger
[36:25] impacter than the depth of the ocean to leave
[36:27] a scar on the ocean floor. So the
[36:30] history of impacts on the Earth is very much
[36:32] muddied by all of these different
[36:35] processes. The Ice Ages have scoured the
[36:37] surface of the Earth clean. We've got
[36:39] weathering, we've got forests, the Earth's
[36:41] surface is actually an incredibly dynamic
[36:43] place compared to the Moon. If you look at
[36:46] the Moon, there are many craters of this kind
[36:48] of size. And one of the things that is
[36:50] actually discussed in the articles online
[36:51] about this is whether this could be a venue
[36:54] for people to learn more in preparation for
[36:56] visits to the Moon where we can go to craters
[36:58] or vice versa. Whether we could learn more
[37:00] about craters like this by going to the ones
[37:02] on the Moon that are the same size but are
[37:04] pristine because we're at a similar
[37:06] location with similar targets in the shooting
[37:08] gallery. But on the Earth everything gets
[37:11] worn away fairly effectively, whereas on the
[37:13] Moon it stays pretty pristine until something
[37:16] else hits it and weathers it away. The only
[37:18] real way you're going to weather lunar
[37:19] craters, um, with a few exceptions, is
[37:22] by other things hitting them and muddying the
[37:24] water. There is going to be a lot more to
[37:27] learn about this. It is still relatively new
[37:30] news. The geologists involved
[37:33] won't be going there year round because it
[37:35] gets really, really cold and really
[37:36] unpleasant in the winter. So there'll be
[37:38] summer expeditions going there, trying to
[37:40] learn more about it, getting more and more
[37:42] samples of it. Because we don't know many
[37:44] craters that are that old on the Earth.
[37:46] Andrew Dunkley: No, this is 390 million
[37:49] years. That's a long time back, isn't
[37:51] it? That's over 300 million years beyond the
[37:54] dinosaur impact.
[37:56] Jonti Horner: Absolutely pretty impressive. It's far from
[37:59] the oldest crater on the Earth, but I would
[38:01] argue that we know far more younger craters
[38:04] than this than. We know older craters than
[38:06] this.
[38:06] Andrew Dunkley: Yeah. Didn't they recently say they found
[38:09] the oldest one in Western Australia? Was it?
[38:12] Jonti Horner: Yeah. Then I think that was a little bit
[38:15] controversial, but there was a lot of talk
[38:16] about shattercons with that one as well.
[38:18] Andrew Dunkley: Yes, there was, Yeah, I remember that.
[38:21] Jonti Horner: You know, these are, uh, we're finding
[38:23] craters more and more and they tell us about
[38:25] the history of the Earth and the heritage of
[38:27] it. With the really old craters, there's even
[38:30] some arguments that the, ah, largest impacts
[38:33] that happened very early on in the Earth's
[38:35] history were actually the seeds of the
[38:38] continents to some degree. There was some
[38:40] amazing work. This is probably actually best
[38:43] part of a decade ago now. But there was great
[38:45] work by Craig o' Neill and his team that were
[38:47] looking at trying to model the initiation of
[38:50] plate tectonics on the Earth. So how did
[38:51] plate tectonics get going? And, um, these
[38:53] incredibly talented geophysicists here in
[38:55] Australia were running models where
[38:58] you start the Earth with no plate tectonics,
[39:00] looking at the interior, looking at how hot
[39:02] it was back then. And if you started the
[39:04] Earth without plate tectonics, plate
[39:06] tectonics didn't happen. And uh, what they
[39:08] thought could be the smoking gun was that you
[39:11] had impacts that caused a big impulse of
[39:14] energy and motion in the mantle
[39:17] that triggered a downwelling which would then
[39:19] trigger an upwelling and you could get impact
[39:21] induced plate tectonics which would then
[39:24] cause these things to maybe even give you the
[39:26] seeds of the continents of the earliest
[39:28] continents. And that's an
[39:31] awesome storey. The videos that they made of
[39:32] their simulations were fabulous. And
[39:35] um, yeah, it's amazing what more there is
[39:37] still to learn, I guess.
[39:38] Andrew Dunkley: Yeah, absolutely true. And this is another
[39:41] storey that's been picked up by Orlin Sundry.
[39:44] Uh, so, um, yeah, you shouldn't have any
[39:46] trouble finding it if you do, um, a search
[39:48] for the Canadian amateur astronomer who was
[39:51] planning his holiday. And uh, the storey will
[39:53] pop up just about everywhere. Space.com, the
[39:56] Smithsonian magazine, et cetera, et cetera.
[39:58] Uh, and uh, by, by now,
[40:01] when you hear this episode or very close to
[40:04] this point in time, uh, the team
[40:07] that uh, made the discovery will be
[40:09] presenting their work at the 88th Annual
[40:11] Meeting of the Meteor. Uh,
[40:14] meteoritis. I can't say
[40:17] it, uh, Meteorocital
[40:20] Society in Germany, I think. That's right. I
[40:22] don't know. Anyway, yeah, look it up. It's a
[40:25] great yarn.
[40:25] Uh, we've had a very rocky programme today.
[40:29] Um, Jonty, it's been fascinating the
[40:32] way those storeys all dovetailed into each
[40:34] other. Uh, and we're at the end. Thank you
[40:36] very much. Nice to see you again.
[40:39] Jonti Horner: Uh, it's good to be back. Thank you for
[40:40] having me and hope
[40:41] Andrew Dunkley: Fred Watson's enjoying his jaunt
[40:44] chasing a, uh, solar eclipse.
[40:45] Jonti Horner: Yes, yes, it's a hard life but somebody's got
[40:48] to do it.
[40:48] Andrew Dunkley: Absolutely true. I'm waiting for one to come
[40:50] to me. I only have to wait two more years.
[40:52] Jonti Horner: Two more years.
[40:54] Andrew Dunkley: Thanks.
[40:54] Jonti Horner: And it'll be cloudy. You know it's going to
[40:56] be cloudy.
[40:56] Andrew Dunkley: Oh yeah, it's probably going to be raining
[40:57] training and I'm m giving up a game of golf
[41:00] for it too. All right, thanks Jonty. We'll
[41:02] see you soon. Yeah, It's a pleasure,
[41:05] Professor Jonty Horner, professor of
[41:06] Astrophysics at the University of Southern
[41:08] Queensland. Don't forget, uh, to visit us
[41:11] online while uh, you are, ah, waiting for the
[41:13] next episode,
[41:14] spacenutspodcast.com
[41:17] and have a look around while you're there.
[41:18] Visit the shop, etc etc and thanks to Huw in
[41:21] the studio couldn't be with us today. Um, put
[41:23] his home address in Google Maps. We haven't
[41:25] seen him since. And from me, Andrew Dunkley.
[41:27] Thanks for your company. We'll see you on the
[41:29] next next episode of Space Nuts. Bye. Bye.
[41:33] Jonti Horner: You've been listening to the Space Nuts
[41:35] podcast, available at
[41:38] Apple Podcasts, Spotify,
[41:40] iHeartRadio or your favourite podcast
[41:43] player. You can also stream on
[41:44] demand@bytes.com M.
[41:46] Andrew Dunkley: This has been another quality podcast
[41:48] production from bytes.com.

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