Andrew Dunkley is joined by Professor Jonti Horner, Professor of Astrophysics at the University of Southern Queensland, for a wide-ranging astronomy update. They cover SpaceX’s out-of-control rocket body hitting the Moon, the imminent launch of the Nancy Grace Roman Observatory, and a new result that may explain the strange origin of some of Neptune’s moons.
We discuss why lunar impacts matter far beyond the Moon itself, how Roman will study exoplanets and dark energy, and why clay minerals on Neptune’s small moons are such a big clue about a violent early solar system.
Key topics
SpaceX’s rocket body impacted the Moon after being left in a long, uncontrolled orbit
Why lunar impacts are a real concern for future habitats, infrastructure, and Apollo heritage sites
The sheer scale of human-made objects that have already hit or landed on the Moon
Elon Musk’s vision for lunar factories, rail-gun launches, and large-scale off-Earth manufacturing
Why the same company could end up both creating the risk and needing to solve it
The Nancy Grace Roman Observatory launching around 9 months ahead of schedule
Roman’s 2.4 metre mirror, 300 megapixel wide-field camera, and hydrazine-fueled journey to L2
How Roman will study dark energy, gravitational lensing, exoplanets, and free-floating planets
New James Webb observations of Neptune’s moons showing clay-type minerals on Larissa and Galatea
Why those clays suggest a much older, more violent system shaped by Triton’s capture and moon-to-moon collisions
Timestamps:
00:00 - Studio prep, muting phones, and getting ready to record
01:53 - Episode intro: SpaceX lunar impact, Roman Observatory, and Neptune moons
03:00 - Jonti Horner joins the show
04:26 - SpaceX rocket body crashes into the Moon
07:03 - Predicted impact plume and expected crater size
08:54 - Korean spacecraft Danuri captures post-impact images
10:19 - Why Moon impacts matter for future lunar bases
11:47 - Protecting Apollo landing sites and lunar archaeology
12:15 - More than 3,000 human-made objects have hit the Moon
14:32 - Law, responsibility, and the problem of cleanup beyond Earth
16:07 - Musk’s plans for Moon factories and Starlink-style expansion
18:12 - Rail guns, Optimus robots, and scaling lunar industry
19:34 - SpaceX’s own industry could be threatened by its own debris
21:24 - Balancing commercial benefits and environmental costs
23:46 - The Nancy Grace Roman Observatory launch approaches
26:03 - Roman’s orbit, hydrazine fuel, and five-year mission plan
27:57 - From WFIRST to Roman: how the telescope evolved
29:23 - Roman’s mirror, 300 megapixel camera, and survey power
30:14 - Exoplanets, microlensing, and the coronagraph
33:29 - Roman’s launch status and the excitement ahead
34:17 - Neptune’s moons and the role of Triton
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00:00:00 --> 00:00:00 Jonti Horner: Hi there.
00:00:00 --> 00:00:02 Andrew Dunkley: Thanks for joining us. My name is Andrew
00:00:02 --> 00:00:05 Dunkley. This is Space Nuts, uh, where we
00:00:05 --> 00:00:08 talk astronomy and space science. And coming
00:00:08 --> 00:00:11 up on Today's programme, uh, SpaceX
00:00:11 --> 00:00:14 in the news, you could say
00:00:14 --> 00:00:16 for all the wrong reasons, but, um, that's
00:00:16 --> 00:00:18 debatable, depending on which part of this
00:00:18 --> 00:00:21 storey that, um, you're talking about. But,
00:00:21 --> 00:00:24 uh, they've hit the moon. Uh, not in a good
00:00:24 --> 00:00:26 way. Uh, we'll also be looking at the
00:00:26 --> 00:00:29 upcoming launch of the Nancy Grace
00:00:29 --> 00:00:32 Roman Observatory. Uh, we've received a lot
00:00:32 --> 00:00:33 of questions from the audience about that,
00:00:33 --> 00:00:36 uh, in recent times and with good reason.
00:00:36 --> 00:00:39 It's a very exciting mission indeed and
00:00:39 --> 00:00:41 if time allows us, we'll, uh, look into a new
00:00:41 --> 00:00:44 study about Neptune's moons. Stick with
00:00:44 --> 00:00:47 us. That's all coming up on this edition of
00:00:47 --> 00:00:49 Space Nuts. 15 seconds.
00:00:49 --> 00:00:51 Jonti Horner: Guidance is internal. 10,
00:00:51 --> 00:00:52 9.
00:00:53 --> 00:00:54 Andrew Dunkley: Ignition sequence start.
00:00:54 --> 00:00:57 Jonti Horner: Space Nuts. 5, 4, 3, 2.
00:00:57 --> 00:01:00 Andrew Dunkley: 1, 2, 3, 4, 5, 5, 4, 3, 2,
00:01:00 --> 00:01:03 1. Space Nuts astronauts report at
00:01:03 --> 00:01:06 Beale. And joining us to, uh, furnish us
00:01:06 --> 00:01:08 with all his knowledge, which will only take
00:01:08 --> 00:01:10 a couple of minutes. No, no, it's not. It'll
00:01:10 --> 00:01:12 take probably a lot longer than that is
00:01:12 --> 00:01:14 Professor Jonty Horner, professor of
00:01:14 --> 00:01:16 Astrophysics at the University of Southern
00:01:16 --> 00:01:17 Queensland. Jonty, hello.
00:01:18 --> 00:01:19 Jonti Horner: Good afternoon. How are you going?
00:01:19 --> 00:01:22 Andrew Dunkley: Uh, good. You should feel good too, because
00:01:22 --> 00:01:24 it's only when I get to like people that I
00:01:24 --> 00:01:25 insult them like that.
00:01:25 --> 00:01:27 Jonti Horner: It's fine. It's just like growing up in
00:01:27 --> 00:01:30 Yorkshire again. It seems to be a
00:01:30 --> 00:01:31 recurring theme with kind of the better parts
00:01:31 --> 00:01:33 of the world is that the more you get on with
00:01:33 --> 00:01:36 people, the more offensively you critic. And,
00:01:36 --> 00:01:39 you know, the
00:01:39 --> 00:01:41 inverse of that being that the less you like
00:01:41 --> 00:01:42 people, the more polite you get. Which
00:01:42 --> 00:01:45 reminds me of Pratchett's almost version of
00:01:45 --> 00:01:47 the Montagues and Capulets with the old
00:01:48 --> 00:01:50 warring aristocracy who'd now got to such a
00:01:51 --> 00:01:53 level of dissatisfaction with one another
00:01:53 --> 00:01:55 that the only polite forms of conversation
00:01:55 --> 00:01:56 were about the weather. And that was it. So
00:01:56 --> 00:01:58 they have these meetings at formal events.
00:01:58 --> 00:02:00 It's like, oh, the weather today is
00:02:00 --> 00:02:02 beautiful, isn't it? M well, you know. Oh,
00:02:02 --> 00:02:03 yes, yes, but you're not.
00:02:04 --> 00:02:07 Andrew Dunkley: Yes, that kind of thing. M. Uh,
00:02:07 --> 00:02:09 we've got a lot to get through and, uh, very
00:02:09 --> 00:02:11 little time to do it, but we will manage as
00:02:11 --> 00:02:12 best we can.
00:02:12 --> 00:02:14 And this, uh, first storey is a bit of a
00:02:14 --> 00:02:17 combo. Two lunar based
00:02:17 --> 00:02:20 storeys and depending on where you sit
00:02:20 --> 00:02:22 on the spectrum of should we or should we
00:02:22 --> 00:02:25 not, um, they could both be considered bad or
00:02:25 --> 00:02:28 one could be sort of considered Good.
00:02:28 --> 00:02:31 Depending on. Yeah, perspective. But,
00:02:31 --> 00:02:34 uh, it's involving SpaceX and, uh, the
00:02:34 --> 00:02:36 recent collision, if you want to call it
00:02:36 --> 00:02:39 that, between a SpaceX rocket body and
00:02:39 --> 00:02:41 the lunar surface, uh, which,
00:02:42 --> 00:02:43 uh, happened not so long ago.
00:02:44 --> 00:02:45 Jonti Horner: Absolutely. I mean, as we're recording this,
00:02:45 --> 00:02:47 it was very, very recent. Very, very.
00:02:47 --> 00:02:50 Listening to this, it's slightly in the
00:02:50 --> 00:02:51 future. And for that reason we didn't talk
00:02:51 --> 00:02:53 about this last time, because last time we
00:02:53 --> 00:02:55 were recording in advance of this happening,
00:02:55 --> 00:02:57 but the broadcast would have gone out after
00:02:57 --> 00:02:58 it happened, which would have been very
00:02:58 --> 00:03:01 bizarre. Now we're recording after the
00:03:01 --> 00:03:02 event and you're hearing after the event, so
00:03:02 --> 00:03:05 at least the time flow is in an appropriate
00:03:05 --> 00:03:05 order.
00:03:06 --> 00:03:09 The storey here is basically
00:03:09 --> 00:03:11 one of celestial littering, which is a
00:03:11 --> 00:03:14 recurring theme. We've got this ongoing
00:03:14 --> 00:03:17 discussion in the past of what goes up, must
00:03:17 --> 00:03:19 come down, and the ongoing issue
00:03:19 --> 00:03:22 with the commercialization of space leading
00:03:22 --> 00:03:24 to a lot of things being launched. And the
00:03:24 --> 00:03:26 vast majority of those things that are
00:03:26 --> 00:03:29 launched return to Earth in a fiery blaze of
00:03:29 --> 00:03:31 glory. We see space junk more and more often
00:03:31 --> 00:03:33 in our skies, but on Earth,
00:03:34 --> 00:03:36 the concerns are primarily about the
00:03:36 --> 00:03:37 atmosphere with the stuff coming back. And
00:03:37 --> 00:03:39 we've talked a lot in the past about the
00:03:39 --> 00:03:41 worries atmospheric scientists have about
00:03:42 --> 00:03:43 dumping all these metals into the upper
00:03:43 --> 00:03:46 atmosphere and what it'll mean. But very
00:03:46 --> 00:03:49 rarely do pieces of space junk make it to the
00:03:49 --> 00:03:51 Earth's surface. And, um, that's because
00:03:51 --> 00:03:52 we've got an atmosphere. The atmosphere is
00:03:52 --> 00:03:54 brilliant and protects the surface of the
00:03:54 --> 00:03:56 Earth from all but the biggest bits of space
00:03:56 --> 00:03:58 junk. Making it down to Earth.
00:03:58 --> 00:03:58 Andrew Dunkley: Yep.
00:03:59 --> 00:04:01 Jonti Horner: Despite that, there is enough concern that
00:04:01 --> 00:04:03 people are, ah, doing things like calculating
00:04:03 --> 00:04:05 the odds for insurance companies of how
00:04:05 --> 00:04:07 likely it is that someone on Earth will die
00:04:07 --> 00:04:09 due to space junkie in the next decade,
00:04:09 --> 00:04:12 things like this. So it's not a null
00:04:12 --> 00:04:14 concern for people on the surface of Earth,
00:04:14 --> 00:04:16 but the odds of something crashing into
00:04:16 --> 00:04:18 Earth's surface, that is something we put up
00:04:18 --> 00:04:20 into orbit, are usually fairly low because
00:04:20 --> 00:04:23 most of it goes away in the atmosphere,
00:04:23 --> 00:04:25 ablates. It doesn't burn up. I'm always
00:04:25 --> 00:04:27 cautious of using the phrasing burn up
00:04:27 --> 00:04:30 because that evokes fire and fire requires
00:04:30 --> 00:04:32 oxygen and it's a chemical reaction. This is
00:04:32 --> 00:04:34 ablation because the air gets superheated and
00:04:34 --> 00:04:37 bakes away the material. But effectively,
00:04:37 --> 00:04:39 colloquially, you'd say this all burns up.
00:04:40 --> 00:04:43 The Earth, though, isn't the only thing out
00:04:43 --> 00:04:46 there that's in the firing line and this
00:04:46 --> 00:04:48 is where this storey comes in. So a while
00:04:48 --> 00:04:51 back, SpaceX launched a couple of
00:04:51 --> 00:04:53 things to head to the Moon. And in order
00:04:53 --> 00:04:55 to do that, they had to boost their rocket to
00:04:55 --> 00:04:57 a higher speed than they normally would do,
00:04:57 --> 00:04:59 which meant that the upper stage of this
00:04:59 --> 00:05:01 rocket went onto a very elongated orbit
00:05:01 --> 00:05:03 around the Earth, uh uh, and then essentially
00:05:03 --> 00:05:06 goes into free fall. It has burned all its
00:05:06 --> 00:05:08 fuel. It is, to all intents and purposes, out
00:05:08 --> 00:05:10 of control. And that means its orbit just
00:05:10 --> 00:05:12 evolves under the gravity of the Earth and
00:05:12 --> 00:05:15 the Moon and the vagaries of the environment
00:05:15 --> 00:05:18 around the Earth. Fast forward to
00:05:18 --> 00:05:20 now and that out of control rocket body
00:05:20 --> 00:05:23 crashed into the Moon. Now, the final
00:05:24 --> 00:05:27 collision was predicted in advance. This was
00:05:27 --> 00:05:29 big news for at least a week beforehand,
00:05:30 --> 00:05:32 and it was estimated roughly where the thing
00:05:32 --> 00:05:34 would hit the Moon. Now you're talking hit
00:05:34 --> 00:05:36 about a fairly hefty chunk of material.
00:05:36 --> 00:05:39 You're talking about, you know, a couple of
00:05:39 --> 00:05:42 thousand kilos, if not more, a fairly big
00:05:42 --> 00:05:45 chunk of material crashing into the Moon's
00:05:45 --> 00:05:48 surface at a speed of a few kilometres per
00:05:48 --> 00:05:51 second. And so the predictions were that
00:05:51 --> 00:05:53 when this hit in the location it hit,
00:05:53 --> 00:05:56 it would dig out a crater maybe 20, 25 metres
00:05:56 --> 00:05:59 across, and kick a load of dust and material
00:05:59 --> 00:06:01 up. It will create a plume that would rise
00:06:01 --> 00:06:03 above the Moon's limb, probably rise as high
00:06:03 --> 00:06:05 as 100 kilometres or so, and slowly fall back
00:06:05 --> 00:06:06 to the surf of the Moon.
00:06:08 --> 00:06:10 The time at which impact was going to happen
00:06:10 --> 00:06:13 was predicted, so astronomers on the part of
00:06:13 --> 00:06:14 the Earth that could see the Moon were
00:06:14 --> 00:06:17 watching to see what happened. Albert,
00:06:17 --> 00:06:19 to be fair, it was predicted that for most
00:06:19 --> 00:06:21 people you would see absolutely nothing. This
00:06:21 --> 00:06:22 thing was going to hit on the daylight side
00:06:22 --> 00:06:25 of the Moon and so reflected sunlight would
00:06:25 --> 00:06:27 obscure pretty much everything.
00:06:28 --> 00:06:31 So people looked, didn't really see anything.
00:06:31 --> 00:06:33 The only really, I think,
00:06:34 --> 00:06:36 strong indication that something was seen
00:06:36 --> 00:06:38 from the ground were a group of people
00:06:38 --> 00:06:40 observing from the Lowell Observatory in the
00:06:40 --> 00:06:42 US who were looking
00:06:43 --> 00:06:46 specifically at very specific wavelengths of
00:06:46 --> 00:06:48 light for sodium ions and lithium ions.
00:06:49 --> 00:06:51 And they saw what appeared to be an impact
00:06:51 --> 00:06:54 plume at the right location at the right
00:06:54 --> 00:06:56 time, kind of confirming that the impact
00:06:56 --> 00:06:57 happened.
00:06:57 --> 00:06:57 Andrew Dunkley: Yeah.
00:06:58 --> 00:07:00 Jonti Horner: Then after the event, the first images came
00:07:00 --> 00:07:02 back of the site that was hit. And those
00:07:02 --> 00:07:05 images came back from a Korean
00:07:05 --> 00:07:08 spacecraft, um, South Korea's first ever
00:07:08 --> 00:07:10 lunar spacecraft, that was launched back in
00:07:10 --> 00:07:12 2022, actually in August
00:07:12 --> 00:07:15 2022 has been floating around, minding its
00:07:15 --> 00:07:17 own business, doing work and pretty much
00:07:17 --> 00:07:19 widely being forgotten. I don't remember ever
00:07:19 --> 00:07:20 talking about this spacecraft before, even
00:07:20 --> 00:07:23 though me. It's a great. Yeah, even though
00:07:23 --> 00:07:25 it's a great achievement that the Koreans got
00:07:25 --> 00:07:26 it into lunar orbit and have been doing great
00:07:26 --> 00:07:27 stuff with it.
00:07:27 --> 00:07:27 Andrew Dunkley: Yeah.
00:07:27 --> 00:07:30 Jonti Horner: But this spacecraft, Dunuri, flew
00:07:30 --> 00:07:33 repeatedly over the area where the impact was
00:07:33 --> 00:07:35 going. And the
00:07:35 --> 00:07:38 Korean, um, Aerospace Research Institute
00:07:38 --> 00:07:41 Carri released an announcement that said,
00:07:41 --> 00:07:44 and I'm quoting here, Dhanuri began
00:07:44 --> 00:07:45 observations about 30 minutes before the
00:07:45 --> 00:07:47 collision and um, through orbit control
00:07:48 --> 00:07:50 passed over the impact site multiple times,
00:07:50 --> 00:07:52 conducting a total of eight imaging
00:07:52 --> 00:07:55 sessions. Through this observation, changes
00:07:55 --> 00:07:57 in the terrain around the impact site and
00:07:57 --> 00:08:00 traces of ejecta spread were confirmed. The
00:08:00 --> 00:08:02 spacecraft secured both pre collision and
00:08:02 --> 00:08:04 immediate post collision footage, enabling
00:08:04 --> 00:08:06 analysis of the changes. Changes, uh, that
00:08:06 --> 00:08:08 have happened. So there are now images only
00:08:08 --> 00:08:10 looks like a little black smudge, but to be
00:08:10 --> 00:08:13 fair, this is an area maybe 20 or 25 metres
00:08:13 --> 00:08:15 across. It's pretty impressive that we can
00:08:15 --> 00:08:18 get images that resolve that impact feature
00:08:18 --> 00:08:21 on the surface of the moon. And I think that
00:08:21 --> 00:08:24 in itself is going to be pretty important
00:08:24 --> 00:08:26 for researchers studying how craters form,
00:08:26 --> 00:08:29 how the lunar impact kind of scenarios
00:08:29 --> 00:08:31 happen. When you're hitting an object with
00:08:31 --> 00:08:34 the regolith, like the moon without an
00:08:34 --> 00:08:36 atmosphere to protect it, all this kind of
00:08:36 --> 00:08:38 stuff's pretty important. But it's doubly
00:08:38 --> 00:08:40 important in the context of our future use of
00:08:40 --> 00:08:42 the moon. You know, NASA have got these plans
00:08:42 --> 00:08:44 to put astronauts in a permanent lunar base
00:08:44 --> 00:08:46 at the South Pole. I know China have
00:08:46 --> 00:08:49 expressed similar aspirations. Elon Musk is
00:08:49 --> 00:08:51 looking at building a lunar industry, which
00:08:51 --> 00:08:54 we'll come to in a minute. Yeah. Ah, if
00:08:54 --> 00:08:56 you're wanting to have permanent presence on
00:08:56 --> 00:08:57 the moon, and particularly permanent human
00:08:57 --> 00:09:00 presence, you need to have a fairly good
00:09:00 --> 00:09:01 understanding of what's going to happen when
00:09:01 --> 00:09:04 impacts happen. You would have also thought
00:09:04 --> 00:09:06 though that you'd like to prevent impacts
00:09:06 --> 00:09:07 from happening, particularly impacts from
00:09:07 --> 00:09:09 things that are out of control. Because if
00:09:09 --> 00:09:10 this thing had come into the Earth's
00:09:10 --> 00:09:13 atmosphere, pretty much all of it would have
00:09:13 --> 00:09:15 ablated. You wouldn't have had to worry on
00:09:15 --> 00:09:17 the ground. On the Moon though,
00:09:18 --> 00:09:21 it makes it to the surface intact. That
00:09:21 --> 00:09:24 size of that impact scar, 25, 27 metres
00:09:24 --> 00:09:27 across, sounds to me very much like the size
00:09:27 --> 00:09:29 of a lunar habitat that you'd build. And the
00:09:29 --> 00:09:31 last thing I would want is to send astronauts
00:09:31 --> 00:09:33 up to the moon and then have a bit of a
00:09:33 --> 00:09:36 discarded rocket crash in and wipe out the
00:09:36 --> 00:09:38 habitat and kill them. Doesn't sound like a
00:09:38 --> 00:09:41 good idea. Not just that it's raised
00:09:41 --> 00:09:43 concerns not only about our kind of future
00:09:43 --> 00:09:44 presence on the moon, but about the
00:09:44 --> 00:09:46 preservation of our archaeological sites on
00:09:46 --> 00:09:49 the moon. We've talked about the incredible
00:09:49 --> 00:09:51 work of Professor Alice Gorman in Adelaide,
00:09:51 --> 00:09:54 who talks about space archaeology and has
00:09:54 --> 00:09:56 Been trying to raise awareness of the
00:09:56 --> 00:09:58 cultural impact of places like the Apollo 11
00:09:58 --> 00:10:00 landing site, where we've got this pristine
00:10:00 --> 00:10:02 record of humanity's first steps on the moon.
00:10:03 --> 00:10:05 And it'd be tragic if something like this
00:10:05 --> 00:10:07 happened and crashed into that. Yeah, it's
00:10:07 --> 00:10:10 really caused a lot of discussion about
00:10:10 --> 00:10:13 what's going on, what we should do about it.
00:10:13 --> 00:10:15 And I don't know that it's a particularly
00:10:15 --> 00:10:17 good look for SpaceX that this has happened,
00:10:17 --> 00:10:18 but it should be stressed that they are far,
00:10:18 --> 00:10:21 uh, from alone. I saw listed on a
00:10:21 --> 00:10:24 BBC article at the time of the
00:10:24 --> 00:10:26 impact detailed some of the other things that
00:10:26 --> 00:10:29 have hit the moon and they reckon that
00:10:30 --> 00:10:33 more than 3 human made objects have
00:10:33 --> 00:10:35 now either landed on or impacted the moon.
00:10:35 --> 00:10:36 Andrew Dunkley: Really? 3?
00:10:36 --> 00:10:38 Jonti Horner: 3 or more.
00:10:38 --> 00:10:40 Andrew Dunkley: I would never have guessed that many.
00:10:40 --> 00:10:42 Jonti Horner: It's astonishing. And that's a total of more
00:10:42 --> 00:10:44 than 190 tonnes of material. Now
00:10:45 --> 00:10:47 some of that landed softly. You know, we
00:10:47 --> 00:10:49 talked about Apollo 11 for example. The lunar
00:10:49 --> 00:10:52 landers from many nations, many nations have
00:10:52 --> 00:10:54 now landed on the moon. We've got crash
00:10:54 --> 00:10:56 landings like the Israeli mission that
00:10:56 --> 00:10:58 spattered tardigrades across the moon because
00:10:58 --> 00:11:00 they could. Which still strikes me as one of
00:11:00 --> 00:11:02 the dumbest space missions ever carried out.
00:11:03 --> 00:11:05 You know, from an astrobiology point of view,
00:11:05 --> 00:11:06 we want to go to places and look for evidence
00:11:06 --> 00:11:08 of life. The last thing you want to do is
00:11:08 --> 00:11:10 smear it over the face of the moon. Hey look,
00:11:10 --> 00:11:12 we've put life there anyway. That's an
00:11:12 --> 00:11:14 entirely other topic. But there's this long
00:11:14 --> 00:11:17 history of things hitting the moon in a both
00:11:17 --> 00:11:19 controlled and uncontrolled fashion. And it's
00:11:19 --> 00:11:21 going to happen more and more the more we put
00:11:21 --> 00:11:22 stuff out there.
00:11:22 --> 00:11:23 Andrew Dunkley: Yep.
00:11:23 --> 00:11:26 Jonti Horner: So it's caused a lot of discussion. It is
00:11:26 --> 00:11:29 really, really interesting. But it does shine
00:11:29 --> 00:11:31 a light on the risk for future missions more
00:11:31 --> 00:11:32 than anything else.
00:11:32 --> 00:11:34 Andrew Dunkley: Yeah, it does. Um,
00:11:34 --> 00:11:36 notwithstanding that, there is,
00:11:37 --> 00:11:40 um, an international law in place that you're
00:11:40 --> 00:11:42 responsible for cleaning up your own mess.
00:11:42 --> 00:11:45 But, um, when things get out of control
00:11:45 --> 00:11:47 or fly off in directions that make them
00:11:47 --> 00:11:50 irretrievable, what can you do
00:11:50 --> 00:11:51 about it?
00:11:51 --> 00:11:54 Jonti Horner: Absolutely. And I would be very interested to
00:11:54 --> 00:11:56 see whether any applications of that law
00:11:57 --> 00:11:59 apply to things beyond the Earth's
00:11:59 --> 00:12:01 atmosphere, because that
00:12:01 --> 00:12:04 gets enforced when you look at people
00:12:04 --> 00:12:06 cleaning up things on Earth. So there was a
00:12:06 --> 00:12:09 storey a few years ago about some SpaceX
00:12:09 --> 00:12:12 rocket parts, um, in the snowy
00:12:12 --> 00:12:14 mountains in Australia and SpaceX in theory
00:12:14 --> 00:12:17 had to come and collect them and there was a
00:12:17 --> 00:12:19 little bit of a lag in that happening.
00:12:19 --> 00:12:20 Similarly, when There was a fragmentation of
00:12:20 --> 00:12:23 one of their big starship test launchers that
00:12:23 --> 00:12:25 uh, dropped debris around the Caribbean.
00:12:25 --> 00:12:27 There was a lot of controversy about whether
00:12:27 --> 00:12:28 they were actually bothering to collect stuff
00:12:28 --> 00:12:29 or not.
00:12:29 --> 00:12:32 Andrew Dunkley: There is a faster way. It's called ebay.
00:12:32 --> 00:12:33 Jonti Horner: Oh absolutely.
00:12:36 --> 00:12:38 This is kind of an ongoing thing and I'm not
00:12:38 --> 00:12:41 sure that once again legislation has kept
00:12:41 --> 00:12:44 up with our use. We were talking about this
00:12:44 --> 00:12:46 last week with satellites I think, and with
00:12:46 --> 00:12:49 the FAA and FCC approving things but making
00:12:49 --> 00:12:51 it very clear that they weren't there to
00:12:51 --> 00:12:53 judge on whether the use of space was
00:12:53 --> 00:12:54 sensible. They were just ruling on their
00:12:54 --> 00:12:57 small area of influence and abrogating other
00:12:57 --> 00:12:58 responsibility.
00:12:58 --> 00:13:00 I don't think we have yet any real
00:13:01 --> 00:13:04 global pathway to improving things and
00:13:04 --> 00:13:06 getting a better handle on what we should and
00:13:06 --> 00:13:08 shouldn't do. But the discussions are
00:13:08 --> 00:13:10 happening and every time something like this
00:13:10 --> 00:13:12 comes along it further prompts those
00:13:12 --> 00:13:14 discussions and raises awareness of the
00:13:14 --> 00:13:15 problem, I guess.
00:13:15 --> 00:13:18 Andrew Dunkley: Yes. And uh, once people are
00:13:18 --> 00:13:20 up there in a permanent or semi permanent
00:13:20 --> 00:13:23 situation, that's when you've really
00:13:23 --> 00:13:25 got to start thinking about these kinds of
00:13:25 --> 00:13:27 problems. Hitting the moon at the moment is
00:13:27 --> 00:13:30 um, it is a risk for
00:13:30 --> 00:13:33 existing infrastructure and historical sites.
00:13:33 --> 00:13:35 But the day will come where people are there
00:13:35 --> 00:13:38 and that creates a whole new ball game. So.
00:13:38 --> 00:13:40 Jonti Horner: And industry will be there. Which brings us
00:13:40 --> 00:13:42 to the second half of this storey.
00:13:42 --> 00:13:44 Andrew Dunkley: Well, let's, let's get into that because this
00:13:44 --> 00:13:47 also involves SpaceX and
00:13:47 --> 00:13:50 Elon's big plan is to put a,
00:13:50 --> 00:13:53 um, uh, manufacturing plant on
00:13:53 --> 00:13:55 the moon to build uh, his
00:13:55 --> 00:13:58 starmind AI satellite array.
00:13:59 --> 00:14:02 Uh, and it looks like that this will be a
00:14:02 --> 00:14:04 fully automated system. They'll manufacture
00:14:04 --> 00:14:07 these things and launch them from the moon.
00:14:07 --> 00:14:10 And we're talking like, I don't
00:14:10 --> 00:14:12 know, M. Is it a million of these things?
00:14:12 --> 00:14:13 Jonti Horner: That's what it wants to do.
00:14:14 --> 00:14:16 Andrew Dunkley: Yeah, that's. I mean this is the stuff of
00:14:16 --> 00:14:19 science fiction, but it's rapidly becoming
00:14:19 --> 00:14:20 something real, isn't it?
00:14:21 --> 00:14:23 Jonti Horner: It is. And I mean we've discussed the light
00:14:23 --> 00:14:25 pollution side of this repeatedly on the
00:14:25 --> 00:14:28 show, both myself and Fred Watson. This
00:14:28 --> 00:14:31 StarMind idea is the idea that
00:14:31 --> 00:14:34 they will launch essentially data centres and
00:14:34 --> 00:14:36 AI centres into Earth orbit to farm
00:14:36 --> 00:14:38 solar energy and you'll have these
00:14:40 --> 00:14:42 heavily computing based satellites with
00:14:42 --> 00:14:45 enormous solar panels probably at a
00:14:45 --> 00:14:47 relatively high altitude above the Earth so
00:14:47 --> 00:14:50 that they can get permanent sunshine, which I
00:14:50 --> 00:14:51 know a number of reports over the last few
00:14:51 --> 00:14:54 months since this has talked about have
00:14:54 --> 00:14:56 spoken about how this will give a visible
00:14:56 --> 00:14:58 ring in the night sky that'll be visible
00:14:58 --> 00:15:01 all night from all locations on the Earth.
00:15:01 --> 00:15:03 And it'll be like living with a
00:15:03 --> 00:15:06 narrow, very thin ring, a bit like Saturn's
00:15:06 --> 00:15:08 rings, but just a single ring rather than
00:15:08 --> 00:15:11 really broad one. Lots of concern,
00:15:11 --> 00:15:14 lots of speculation about that. This
00:15:14 --> 00:15:16 storey relates to one of the
00:15:17 --> 00:15:19 quarterly calls that
00:15:19 --> 00:15:21 SpaceX are having. This is apparently the
00:15:21 --> 00:15:23 first ever, but they're going to happen every
00:15:23 --> 00:15:25 quarter and it's probably something that's
00:15:25 --> 00:15:27 followed on from the listing of SpaceX on the
00:15:27 --> 00:15:29 stock exchange and that where
00:15:30 --> 00:15:33 Musk talks to the investors. And um, this
00:15:33 --> 00:15:35 call was on the 4th of August, just under a
00:15:35 --> 00:15:37 week ago for me, but by the time you hear
00:15:37 --> 00:15:40 this three weeks ago. And in
00:15:40 --> 00:15:43 that call, Musk talked widely about
00:15:43 --> 00:15:46 his dreams to put factories on the
00:15:46 --> 00:15:47 moon. This is something he's talked about
00:15:47 --> 00:15:50 before, so it's not utterly new, but he's
00:15:50 --> 00:15:52 given more detail of what they want. He
00:15:52 --> 00:15:54 talks about landing a huge amount of tonnage
00:15:54 --> 00:15:57 on the moon to build factories. The factories
00:15:57 --> 00:16:00 will use robots akin to the Optimus robots
00:16:00 --> 00:16:02 that they use in the, um, Tesla car
00:16:02 --> 00:16:04 manufacturers, I think. And he's already
00:16:04 --> 00:16:06 talking about sending some of those Optimus
00:16:06 --> 00:16:09 robots to Mars. He wants to use
00:16:09 --> 00:16:12 the moon to build these starmind
00:16:12 --> 00:16:14 AI satellites which he'll then launch with
00:16:14 --> 00:16:17 giant rail guns using the obs abundant solar
00:16:17 --> 00:16:19 power you can generate on the moon, building
00:16:19 --> 00:16:21 a really, really, really long track with a
00:16:21 --> 00:16:24 kink at the end where you can accelerate
00:16:24 --> 00:16:26 using magnets, something to launch
00:16:27 --> 00:16:28 speed. And this is again something that's
00:16:28 --> 00:16:30 featured heavily in science fiction over the
00:16:30 --> 00:16:32 years as a method for launching things from
00:16:33 --> 00:16:35 bodies without an atmosphere. All makes
00:16:35 --> 00:16:38 sense, but the idea he's got is
00:16:38 --> 00:16:41 that, uh, by going onto the moon, he can
00:16:41 --> 00:16:44 scale up manufacturing to get to being a
00:16:44 --> 00:16:47 factor of a thousand and a factor of
00:16:47 --> 00:16:49 a million times more than he has on Earth.
00:16:50 --> 00:16:53 So a huge, vast expansion in their
00:16:53 --> 00:16:56 building capacity. And it's a kind
00:16:56 --> 00:16:59 of thing that, huh, many people might poo
00:16:59 --> 00:17:00 poo, but I think if we were talking a decade
00:17:00 --> 00:17:02 ago, people would have been poo pooing the
00:17:02 --> 00:17:04 idea of Starlink. And he's been very
00:17:04 --> 00:17:06 successful getting that off the ground and up
00:17:06 --> 00:17:09 and running. So I wouldn't rule this out. And
00:17:09 --> 00:17:11 long term we are seeing the dawn
00:17:11 --> 00:17:13 of the commercial use of space and the
00:17:13 --> 00:17:15 commercial exploitation of the moon and
00:17:15 --> 00:17:18 asteroids is sure to follow. So it wouldn't
00:17:18 --> 00:17:19 surprise me if other companies are having
00:17:19 --> 00:17:21 similar ideas and it may maybe that SpaceX
00:17:22 --> 00:17:24 are the first but not the only ones to do
00:17:24 --> 00:17:27 this if it happens. What I
00:17:27 --> 00:17:30 found interesting about this is this storey's
00:17:30 --> 00:17:32 going round at exactly the same time that
00:17:32 --> 00:17:34 we're talking about the uncontrolled crash of
00:17:34 --> 00:17:37 the SpaceX rocket to the moon. Which means
00:17:37 --> 00:17:40 you've got this almost a conflict of interest
00:17:40 --> 00:17:43 for SpaceX here because on the one hand
00:17:43 --> 00:17:45 they want to be able to launch their rockets.
00:17:45 --> 00:17:46 They've got to get that tonnage into space,
00:17:46 --> 00:17:48 as Musk says. And if they're launching things
00:17:48 --> 00:17:51 to the moon, that'll leave a lot of rocket
00:17:51 --> 00:17:52 bodies on orbits that could event actually
00:17:52 --> 00:17:55 impact the moon and they're out of control.
00:17:55 --> 00:17:57 Yet at the same time he's looking at building
00:17:57 --> 00:18:00 capacity for manufacturing on the surface of
00:18:00 --> 00:18:03 the moon. Now that strikes me that on the
00:18:03 --> 00:18:05 one hand he's increasing the risk that his
00:18:06 --> 00:18:08 industry will be damaged by his own industry,
00:18:08 --> 00:18:10 if that makes sense. Oh yeah, there's always
00:18:10 --> 00:18:12 a possibility that one of his rockets will
00:18:12 --> 00:18:14 crash into one of his factories. So it may
00:18:14 --> 00:18:17 well be that that leads to a certain amount
00:18:17 --> 00:18:19 of self interest in looking at ways to manage
00:18:19 --> 00:18:21 it that the outcry of astronomers wouldn't.
00:18:22 --> 00:18:25 It's a lot more impelling for
00:18:25 --> 00:18:27 a company like SpaceX to want to find a
00:18:27 --> 00:18:29 solution to a problem that will directly
00:18:29 --> 00:18:32 impact them than a problem that's just
00:18:32 --> 00:18:33 upsetting a few people and is considered a
00:18:33 --> 00:18:35 little niche. So it's going to be really
00:18:35 --> 00:18:37 interesting to see how these two things kind
00:18:37 --> 00:18:38 of develop in parallel, I think.
00:18:39 --> 00:18:42 Andrew Dunkley: Yeah. Uh, Elon Musk is um,
00:18:42 --> 00:18:45 to some a visionary, to others an absolute
00:18:45 --> 00:18:48 nutter. But uh, when you look at what he's
00:18:48 --> 00:18:50 achieved, you can't deny it. And when he
00:18:50 --> 00:18:52 starts to talk about doing things like this,
00:18:53 --> 00:18:56 you can't say it won't happen because
00:18:57 --> 00:18:59 he's proven that he'll put his money where
00:18:59 --> 00:19:00 his mouth is over and over again.
00:19:01 --> 00:19:03 Jonti Horner: Yeah. Um, and I do try when I'm talking about
00:19:03 --> 00:19:05 this, I know I fail sometimes, but I try to
00:19:05 --> 00:19:07 be as evenhanded as I can be M because I
00:19:07 --> 00:19:10 think very few people are purely good or
00:19:10 --> 00:19:11 purely evil. There's good and bad to most
00:19:11 --> 00:19:13 people and there are good and bad to the
00:19:13 --> 00:19:15 things that people do. And when we've talked
00:19:15 --> 00:19:18 a lot about Starlink, I always want
00:19:18 --> 00:19:20 to be a parent of stress that there is real
00:19:20 --> 00:19:21 benefit comes from this as well. Cause I
00:19:21 --> 00:19:23 think a big mistake people make is only
00:19:23 --> 00:19:26 focusing on the negative. And that doesn't
00:19:26 --> 00:19:28 put you in a good position. You need to look
00:19:28 --> 00:19:30 not to stop things entirely, but to look for
00:19:30 --> 00:19:32 a position where you get the maximum benefit
00:19:32 --> 00:19:33 for the minimum cost. You know that sweet
00:19:33 --> 00:19:34 spot.
00:19:34 --> 00:19:34 Andrew Dunkley: Yeah.
00:19:34 --> 00:19:37 Jonti Horner: And it is undeniable that Starlink has
00:19:37 --> 00:19:40 brought with it great benefits to people
00:19:40 --> 00:19:42 in terms of being able to access the Internet
00:19:42 --> 00:19:44 and access communication where previously
00:19:44 --> 00:19:45 they weren't able to see, were too remote.
00:19:46 --> 00:19:48 It's also come with associated problems and I
00:19:48 --> 00:19:51 think this kind of endeavour is going to be
00:19:51 --> 00:19:54 the same. It's also probably very fair to say
00:19:54 --> 00:19:56 that that commercial use of the Moon and
00:19:56 --> 00:19:58 commercial use of other things in the solar
00:19:58 --> 00:20:00 system is going to happen whether SpaceX do
00:20:00 --> 00:20:02 it or not. But they're very much at the
00:20:02 --> 00:20:05 forefront. So I don't see an argument to be
00:20:05 --> 00:20:06 made for just saying, oh well, they should
00:20:06 --> 00:20:08 stop this and think about it. I think what's
00:20:08 --> 00:20:10 really important is all this stuff is
00:20:10 --> 00:20:13 discussed very publicly and, um,
00:20:13 --> 00:20:16 we figure out what humanity as a
00:20:16 --> 00:20:19 whole thinks is the right balance to have.
00:20:19 --> 00:20:21 And that's challenging. I mean, it's not a
00:20:21 --> 00:20:23 case of nothing and it's not a case of
00:20:23 --> 00:20:25 everything. But it's probably going to be the
00:20:25 --> 00:20:28 case that, uh, the use of the Moon is just
00:20:28 --> 00:20:30 like the use of low Earth orbit, where the
00:20:30 --> 00:20:32 commercial use rapidly outstrips our,
00:20:32 --> 00:20:34 uh, abilities, at least at first, to
00:20:34 --> 00:20:36 legislate around it and then the legislation
00:20:36 --> 00:20:39 will come afterwards in much the same way. We
00:20:39 --> 00:20:41 were talking last week about previous
00:20:41 --> 00:20:43 examples being things like the Internet or
00:20:43 --> 00:20:45 even the printing press, things like this.
00:20:45 --> 00:20:48 The use always outstrips the legislation.
00:20:48 --> 00:20:50 Then the legislation sprints capture.
00:20:51 --> 00:20:54 Andrew Dunkley: Yes, uh, well, it crawls
00:20:54 --> 00:20:56 in some cases, but I know what you mean. Um,
00:20:57 --> 00:20:59 and look, if SpaceX don't do this, as you
00:20:59 --> 00:21:02 said, someone else will. It's, um, you know,
00:21:02 --> 00:21:04 everyone can point the finger at Elon Musk
00:21:04 --> 00:21:07 and SpaceX and say, oh, naughty. But
00:21:07 --> 00:21:10 if they say, look, yeah, okay, we agree
00:21:10 --> 00:21:12 it's a bad idea, we won't do it, someone else
00:21:12 --> 00:21:14 will. Absolutely, most certainly.
00:21:15 --> 00:21:18 So, uh, it's probably more a case of finding
00:21:18 --> 00:21:21 a way to manage this properly into the future
00:21:21 --> 00:21:23 rather than just saying, no, it shouldn't
00:21:23 --> 00:21:26 happen, shouldn't be done, no way, no how,
00:21:26 --> 00:21:28 because it will happen regardless.
00:21:29 --> 00:21:31 Interesting times ahead. Uh, yeah, a couple
00:21:31 --> 00:21:34 of interesting storeys focused, uh, on the
00:21:34 --> 00:21:35 Moon. And if you want to read about that
00:21:35 --> 00:21:38 impact, you can do that at,
00:21:38 --> 00:21:39 uh, the
00:21:40 --> 00:21:43 space.com website. I knew I'd find it there
00:21:43 --> 00:21:45 somewhere. This is Space Nuts with Andrew
00:21:45 --> 00:21:47 Dunkley and Professor Jonty Horner.
00:21:49 --> 00:21:51 I believe that this nation should commit
00:21:51 --> 00:21:53 itself to achieving the goal,
00:21:54 --> 00:21:57 before this decade is out, of landing a
00:21:57 --> 00:21:57 man
00:21:57 --> 00:21:59 Jonti Horner: on the moon and returning him safely to the
00:21:59 --> 00:22:01 Earth. These nuts.
00:22:02 --> 00:22:04 Andrew Dunkley: Now to something very exciting. We've been
00:22:04 --> 00:22:07 building up to this for quite some time and
00:22:07 --> 00:22:09 as this podcast, uh, goes
00:22:09 --> 00:22:12 out um, the day of release for this one is
00:22:12 --> 00:22:15 the 27th of August. Uh, we are three
00:22:15 --> 00:22:18 days away from the launch
00:22:18 --> 00:22:20 of the Nancy Grey Space Roman
00:22:20 --> 00:22:23 Observatory. That is big time
00:22:23 --> 00:22:24 excitement.
00:22:24 --> 00:22:26 Jonti Horner: It is of course the caveat is that uh, in the
00:22:26 --> 00:22:28 couple of weeks between recording this and it
00:22:28 --> 00:22:30 going live, it could be delayed change, you
00:22:30 --> 00:22:32 know, it's like, like the trains in the uk,
00:22:32 --> 00:22:34 never trust that they're going to arrive
00:22:34 --> 00:22:35 until they actually have done and even then
00:22:35 --> 00:22:38 be sceptical. Yeah, it's that kind of
00:22:38 --> 00:22:41 thing. But in this case that would be quite
00:22:41 --> 00:22:42 startling because until very recently
00:22:44 --> 00:22:45 everybody was expecting this telescope to be
00:22:45 --> 00:22:48 launched next year. So the, the launch,
00:22:48 --> 00:22:51 if it goes ahead on 30 August
00:22:51 --> 00:22:53 will be a launch that is nine months ahead of
00:22:53 --> 00:22:55 schedule, which is very, very cool. Now the
00:22:55 --> 00:22:58 scheduled launch time at the time of
00:22:58 --> 00:23:00 recording will be the 30th of August at
00:23:00 --> 00:23:03 uh, 9:26pm Australian
00:23:03 --> 00:23:05 Eastern Standard Time, which is 11, um,
00:23:05 --> 00:23:08 26:00am Universal Time or Greenwich Mean
00:23:08 --> 00:23:11 Time. I think a lot of these launches get
00:23:11 --> 00:23:13 streamed online so for those of you who are
00:23:13 --> 00:23:15 keen, there will almost certainly be live
00:23:15 --> 00:23:17 coverage of that. Uh, and a lot of very
00:23:17 --> 00:23:18 nervous people watching the launch hoping
00:23:18 --> 00:23:21 that it doesn't turn into a. Which has
00:23:21 --> 00:23:22 happened before.
00:23:22 --> 00:23:25 Andrew Dunkley: It has. We don't want to think about
00:23:25 --> 00:23:27 that. We're talking $4 billion
00:23:28 --> 00:23:29 worth of hardware.
00:23:29 --> 00:23:31 Jonti Horner: We are. But I mean this is why there are
00:23:31 --> 00:23:34 insurance policies, right? It's um,
00:23:35 --> 00:23:36 there is a risk.
00:23:36 --> 00:23:38 Andrew Dunkley: I'm surprised you'd find an insurance company
00:23:38 --> 00:23:39 willing.
00:23:40 --> 00:23:41 Jonti Horner: I think it's become fairly big business
00:23:41 --> 00:23:43 actually. I mean it's not my area, but I
00:23:43 --> 00:23:46 remember when we went to meetings
00:23:46 --> 00:23:49 a few years ago about off Earth resource
00:23:49 --> 00:23:50 collection, there was discussion about
00:23:50 --> 00:23:53 insurance and stuff like that and apparently
00:23:53 --> 00:23:55 there are insurance underwriters who insure
00:23:55 --> 00:23:58 satellites and launchers and
00:23:58 --> 00:24:00 I think I seem to remember, although I stand
00:24:00 --> 00:24:02 to be corrected on this, that the cluster
00:24:02 --> 00:24:05 mission probably 15, 20 years ago
00:24:05 --> 00:24:07 now blew up on the launch pad and insurance
00:24:07 --> 00:24:10 allowed them to essentially rebuild it and
00:24:10 --> 00:24:13 launch it again. Um, so it does happen, but
00:24:13 --> 00:24:16 fingers crossed, touch wood, there will be no
00:24:16 --> 00:24:17 problems with this. And um, what will happen
00:24:17 --> 00:24:20 is that on the 30th of August a uh, rocket
00:24:20 --> 00:24:23 will take off. SpaceX rocket that will carry
00:24:23 --> 00:24:25 Nancy Grace Roman Telescope
00:24:25 --> 00:24:28 into Earth orbit and beyond will boost
00:24:28 --> 00:24:30 hard, um, just like happened with the James
00:24:30 --> 00:24:32 Webb Space Telescope to give it a good kick
00:24:32 --> 00:24:34 because this thing is destined to go out to
00:24:34 --> 00:24:37 join James Webb at the outer Lagrange point,
00:24:37 --> 00:24:39 um, beyond the Earth, uh, so about a million
00:24:39 --> 00:24:41 kilometres further from the sun than the
00:24:41 --> 00:24:43 Earth is but moving in lockstep with our ah,
00:24:43 --> 00:24:45 at this kind of gravitational sweet spot
00:24:45 --> 00:24:48 where you can hang around fairly safely for a
00:24:48 --> 00:24:50 long time. To do that it is
00:24:50 --> 00:24:53 loaded with what is described as a very
00:24:53 --> 00:24:56 toxic fuel, um, hydrazine.
00:24:57 --> 00:24:59 They want to move away from it but until they
00:24:59 --> 00:25:00 find a better alternative they haven't yet.
00:25:00 --> 00:25:03 So as we talk right now
00:25:03 --> 00:25:06 the spacecraft has been fully fueled
00:25:06 --> 00:25:08 which is why they're fairly confident that
00:25:08 --> 00:25:11 they'll launch on time. That amount of fuel
00:25:11 --> 00:25:14 sets the lifetime of the mission. And there
00:25:14 --> 00:25:15 were similar discussions with Jim James Webb
00:25:15 --> 00:25:18 when it launched a few years ago in that the
00:25:18 --> 00:25:21 nominal mission is five years. So once Nancy
00:25:21 --> 00:25:23 Grace Roman gets to the L2 point and that
00:25:23 --> 00:25:25 journey will take about 100 days from the
00:25:25 --> 00:25:27 launch it is scheduled to have
00:25:28 --> 00:25:30 around a five year mission.
00:25:31 --> 00:25:34 May have a longer mission than that if it
00:25:34 --> 00:25:37 manages to keep hold of its hydrozine fuel.
00:25:37 --> 00:25:39 So what happened with James Webb was uh,
00:25:39 --> 00:25:41 everybody was delighted with how accurately
00:25:41 --> 00:25:43 and beautifully it launched so it needed to
00:25:43 --> 00:25:46 use less fuel to get on station which meant
00:25:46 --> 00:25:48 that have more fuel for a longer life
00:25:49 --> 00:25:52 and therefore the projected mission went from
00:25:52 --> 00:25:55 five years to maybe 10 or 20. Managed to keep
00:25:55 --> 00:25:57 those sorts of fuel and hopefully fingers
00:25:57 --> 00:26:00 crossed, such wood. Again the same will be
00:26:00 --> 00:26:02 true for Nancy Grace Roman Telescope.
00:26:03 --> 00:26:04 People have been really looking forward to
00:26:04 --> 00:26:07 this. Now the first I remember of Nancy Grace
00:26:07 --> 00:26:09 Roman Telescope was when it used to be badged
00:26:09 --> 00:26:11 as wfirst a Wide Field Infrared Survey
00:26:11 --> 00:26:13 Telescope. That was kind of the first
00:26:13 --> 00:26:15 proposal and that was going back to 2011,
00:26:15 --> 00:26:18 2012. And shortly after those first
00:26:18 --> 00:26:21 proposals there was a really interesting
00:26:21 --> 00:26:24 storey came out that NASA had been told
00:26:24 --> 00:26:26 that there were suddenly a number of
00:26:27 --> 00:26:29 what are known as National Reconnaissance
00:26:29 --> 00:26:31 Office telescopes made m by the Harris
00:26:31 --> 00:26:34 Corporation. Um, the nro
00:26:34 --> 00:26:37 uh, offered to donate two telescopes to
00:26:37 --> 00:26:40 NASA which are telescopes comparable in
00:26:40 --> 00:26:41 size to the Hubble Space Telescope but a
00:26:41 --> 00:26:44 wider field of view. To put that in other
00:26:44 --> 00:26:46 language. Effectively the defence community
00:26:46 --> 00:26:48 in the US said by the way, we've got a couple
00:26:48 --> 00:26:50 of spy satellites that we're not going to use
00:26:50 --> 00:26:52 so do you want them to actually do science?
00:26:53 --> 00:26:56 Which meant at least to me for the first time
00:26:56 --> 00:26:57 I became aware of the fact that there were a
00:26:57 --> 00:26:59 number of Hubble class telescopes orbiting
00:26:59 --> 00:27:02 the Earth. Looking down, um, I hadn't quite
00:27:02 --> 00:27:04 realised spy satellites had got that big and
00:27:04 --> 00:27:07 that impressive. But anyway
00:27:07 --> 00:27:08 that was a really nice
00:27:09 --> 00:27:12 mechanism through which you know you could do
00:27:12 --> 00:27:15 a cool mission a little bit cheaper. That
00:27:15 --> 00:27:16 got a bit of political interest and all the
00:27:16 --> 00:27:19 rest of it. But over time since
00:27:19 --> 00:27:22 the telescope was planned and then approved
00:27:22 --> 00:27:25 and then built. Now, I must confess
00:27:25 --> 00:27:27 that I don't actually know whether the
00:27:27 --> 00:27:29 current iteration of Nancy Grace Roman is a
00:27:29 --> 00:27:31 former spy satellite or whether they moved
00:27:31 --> 00:27:34 away from that. But what it is going to be is
00:27:34 --> 00:27:37 a space telescope with a mirror 2.4 metres
00:27:37 --> 00:27:39 across, which is your Hubble Space Telescope
00:27:39 --> 00:27:42 size, wider field of view than Hubble
00:27:42 --> 00:27:45 that will observe in the optical and in the
00:27:45 --> 00:27:48 near infrared using two instruments. So it's
00:27:48 --> 00:27:50 going to have a very wonderful wide field
00:27:50 --> 00:27:53 camera. This is a camera with
00:27:53 --> 00:27:56 300 megapixels. So
00:27:56 --> 00:27:58 that's a hell of a lot better than the CCD
00:27:58 --> 00:28:01 camera I've got on my digital telescope here.
00:28:01 --> 00:28:04 On my telescope here. Fabulous camera
00:28:04 --> 00:28:06 that will work at both visible and near
00:28:06 --> 00:28:08 infrared, will be able to take take images in
00:28:08 --> 00:28:10 a wide variety of colour bands and things
00:28:10 --> 00:28:12 like this. So that's going to be a fabulous
00:28:13 --> 00:28:15 camera that allows survey work to be done.
00:28:15 --> 00:28:18 And a lot of the work that is planned for
00:28:18 --> 00:28:21 this incredible telescope will be looking at
00:28:21 --> 00:28:22 the kind of cosmology stuff that you get so
00:28:22 --> 00:28:25 many questions about dark energy and
00:28:25 --> 00:28:27 gravitational lensing and things like this.
00:28:27 --> 00:28:29 Stuff that's a bit outside my professional
00:28:29 --> 00:28:32 wheelhouse, but it's also going to be
00:28:32 --> 00:28:34 carrying out an incredible survey looking for
00:28:34 --> 00:28:36 exoplanets. It's going to stare at the bulge
00:28:36 --> 00:28:39 of the Milky Way galaxy, looking for gravity
00:28:39 --> 00:28:41 gravitational microlensing events, which is
00:28:41 --> 00:28:43 when a planet going around a star where we
00:28:43 --> 00:28:45 can see neither the star nor the planet
00:28:46 --> 00:28:48 passes between us and a more distant star
00:28:48 --> 00:28:50 and some of the light from that sour is bent
00:28:50 --> 00:28:52 and focused towards us, causing the star to
00:28:52 --> 00:28:55 brighten and then fade. That microlensing
00:28:55 --> 00:28:57 event lets us detect the object that we can't
00:28:57 --> 00:29:00 see passing by in between and it
00:29:00 --> 00:29:02 will also let us find free floating planets.
00:29:02 --> 00:29:05 So Nancy Grace Roman Telescope still going to
00:29:05 --> 00:29:07 do a fabulous kind of census type survey
00:29:07 --> 00:29:10 of planets towards the middle of our galaxy
00:29:10 --> 00:29:13 using this micro technique. It's
00:29:13 --> 00:29:15 also carrying its other instrument, which is
00:29:15 --> 00:29:18 a really high contrast camera with a very
00:29:18 --> 00:29:21 small field of view, very different, that is
00:29:21 --> 00:29:24 attached to a coronagraph. And a coronagraph
00:29:24 --> 00:29:26 is a fabulous device that allows you to block
00:29:26 --> 00:29:29 out the light from a light source like
00:29:29 --> 00:29:32 a star and allow you to look at things that
00:29:32 --> 00:29:34 are very near to that light source that would
00:29:34 --> 00:29:36 normally be lost in the glare. And um, this
00:29:36 --> 00:29:38 is planned to take advantage of the fact that
00:29:38 --> 00:29:40 this thing's in space. We don't have the
00:29:40 --> 00:29:42 Earth's atmosphere to deal with to
00:29:43 --> 00:29:45 use both the camera and a spectrograph that
00:29:45 --> 00:29:48 are connected to this coronagraph
00:29:48 --> 00:29:51 to look at exoplanets and actually try and
00:29:51 --> 00:29:54 get direct imaging observations of them and
00:29:54 --> 00:29:56 to learn more about their atmospheres. It'll
00:29:56 --> 00:29:57 be used for planets more like the size of
00:29:57 --> 00:30:00 Jupiter than the Earth, but it's going to be
00:30:00 --> 00:30:02 an incredible tool for learning more about
00:30:02 --> 00:30:03 planets around stars like the sun
00:30:03 --> 00:30:04 effectively.
00:30:04 --> 00:30:07 Andrew Dunkley: Yeah, it's going to be very exciting and uh,
00:30:07 --> 00:30:09 can't wait. Hopefully everything will run
00:30:09 --> 00:30:12 according to plan on August 30th, which
00:30:12 --> 00:30:14 uh, by the time this, this podcast is
00:30:14 --> 00:30:17 released we'll be three days away. And
00:30:18 --> 00:30:21 um, yeah, we wait with bated breath. Uh, it's
00:30:21 --> 00:30:23 only got to go a million kilometres to get
00:30:23 --> 00:30:26 where it's going which will take um, it's not
00:30:26 --> 00:30:28 a heck of a long trip but it's going to take
00:30:28 --> 00:30:31 them ah, a little while to get there. I can't
00:30:31 --> 00:30:32 remember how long it was now.
00:30:33 --> 00:30:35 Jonti Horner: Oh well it's 100 days to roll on out to the
00:30:35 --> 00:30:37 Lagrange point for a start and then it'll be
00:30:37 --> 00:30:40 time to get yourself fired up and
00:30:40 --> 00:30:42 get all the testing done and all the rest of
00:30:42 --> 00:30:44 it. But it's going to be a fabulous tool and
00:30:44 --> 00:30:47 I think, I know I myself, my
00:30:47 --> 00:30:49 research is mainly theoretical, I'm mainly
00:30:49 --> 00:30:51 working on computers and to be honest I'm at
00:30:51 --> 00:30:53 a stage in my career and I'm sure Fred Watson
00:30:53 --> 00:30:54 can empathise with this where I'm becoming
00:30:54 --> 00:30:56 more of an administrator and a supervisor
00:30:56 --> 00:30:58 than I am a researcher. But um, I know
00:30:58 --> 00:31:00 colleagues of mine at UNISQ have been very
00:31:00 --> 00:31:03 successful in getting time to use the James
00:31:03 --> 00:31:05 Webb Space Telescope to study exoplanet
00:31:05 --> 00:31:06 atmospheres. And I'm thinking here
00:31:06 --> 00:31:09 particularly of George Zhao and Chelsea Huang
00:31:09 --> 00:31:11 who are really uh, truly world class
00:31:11 --> 00:31:13 scientists and I think they are waiting with
00:31:13 --> 00:31:15 bated breath to see what be able to do with
00:31:15 --> 00:31:18 this. So yes, you'll get a lot of discoveries
00:31:18 --> 00:31:20 coming out from the us but we will have
00:31:20 --> 00:31:22 Australian involvement looking at this and
00:31:22 --> 00:31:24 getting amazing results right here in
00:31:24 --> 00:31:26 Australia and for people living in other
00:31:26 --> 00:31:28 countries, other countries will have their
00:31:28 --> 00:31:30 own scientists beavering away
00:31:31 --> 00:31:33 using Nancy Grey's Roman telescope to do
00:31:33 --> 00:31:35 amazing, amazing things indeed.
00:31:35 --> 00:31:38 Andrew Dunkley: And uh, we will uh, obviously let you
00:31:38 --> 00:31:41 know how it all goes uh, once we know
00:31:42 --> 00:31:44 whether or not it launched on time, whether
00:31:44 --> 00:31:46 or not anything fingers crossed happened to
00:31:46 --> 00:31:49 uh, slow it down, whatever. Hopefully not. It
00:31:49 --> 00:31:52 should all go according to plan one
00:31:52 --> 00:31:55 hopes. Um, anyway we'll watch with interest
00:31:55 --> 00:31:57 and you can read that storey also on
00:31:57 --> 00:31:59 space.com, but uh, there are plenty of
00:31:59 --> 00:32:01 platforms carrying the storey of the Nancy
00:32:01 --> 00:32:03 Grace Roman Observatory. And um,
00:32:03 --> 00:32:06 if all goes to plan, there'll be many, many
00:32:06 --> 00:32:08 more storeys in a few days time. This is
00:32:08 --> 00:32:11 Space Nuts and you're uh, with Andrew Dunkley
00:32:11 --> 00:32:12 and Professor Jonty Horn.
00:32:16 --> 00:32:18 Jonti Horner: Three, two, one.
00:32:18 --> 00:32:20 Space Nuts.
00:32:20 --> 00:32:22 Andrew Dunkley: And seeing we've got a few minutes up our
00:32:22 --> 00:32:24 sleeve, we'll go on to our third and final
00:32:24 --> 00:32:25 storey.
00:32:25 --> 00:32:27 And this one involves three, uh,
00:32:28 --> 00:32:30 moons of Neptune which they think,
00:32:30 --> 00:32:33 according to a new study, might have uh, been
00:32:33 --> 00:32:35 created in a rather
00:32:36 --> 00:32:38 um, Earth, uh, shattering or Neptune
00:32:38 --> 00:32:41 shattering way involving the moon
00:32:41 --> 00:32:43 Triton, which is also a very mysterious
00:32:43 --> 00:32:45 place in our solar system.
00:32:46 --> 00:32:48 Jonti Horner: Yeah, and this is a fascinating one. Now some
00:32:48 --> 00:32:50 of the coverage of this has been kind of
00:32:50 --> 00:32:53 presenting this as a new theory that's come
00:32:53 --> 00:32:54 up from the observations. And to me it's
00:32:54 --> 00:32:57 actually a bit the other way around where
00:32:57 --> 00:32:59 these are observations that are potentially
00:32:59 --> 00:33:01 supporting ideas that have been held for a
00:33:01 --> 00:33:04 fair while. Now. Neptune has a
00:33:04 --> 00:33:07 system of satellites like the other giant
00:33:07 --> 00:33:09 planets in the ice giant Uranus. But
00:33:09 --> 00:33:12 Neptune's is unusual. You've a
00:33:12 --> 00:33:15 real behemoth of a moon in the form of Triton
00:33:15 --> 00:33:18 that along with our moon is one of the two
00:33:18 --> 00:33:20 oddest moons of any planet in the solar
00:33:20 --> 00:33:23 system. To give a bit of context from that
00:33:23 --> 00:33:26 and take a step back, aside from our moon and
00:33:26 --> 00:33:29 Triton, all of the other hundreds of moons
00:33:29 --> 00:33:31 in the solar system fall into two real
00:33:31 --> 00:33:33 categories. You've got regular satellites
00:33:34 --> 00:33:37 which fall on orbits
00:33:37 --> 00:33:39 that are above the equators of their planets,
00:33:39 --> 00:33:41 are very close in and they're going around on
00:33:41 --> 00:33:43 circular orbits that are in the same
00:33:43 --> 00:33:45 direction as a planet's spin. And they're
00:33:45 --> 00:33:47 thought to have formed particularly around
00:33:47 --> 00:33:50 the gas giant planets, but also around Uranus
00:33:50 --> 00:33:52 and Neptune in much the same way that the
00:33:52 --> 00:33:53 planets formed around the sun in that you had
00:33:53 --> 00:33:55 a disc of material around the planet and
00:33:55 --> 00:33:57 moons formed in that disc. They're quite
00:33:57 --> 00:34:00 compact and close in. You've
00:34:00 --> 00:34:02 then got irregular satellites which are um,
00:34:02 --> 00:34:04 much, much, much further from their planets,
00:34:05 --> 00:34:07 um, are found around. The outer planets
00:34:08 --> 00:34:11 are moving on a wide range of very elongated,
00:34:11 --> 00:34:14 often retrograde orbits to be captured
00:34:14 --> 00:34:16 objects that have then been smashed into
00:34:16 --> 00:34:19 pieces, giving you families of satellites.
00:34:19 --> 00:34:21 And it's these that give Jupiter and Saturn
00:34:21 --> 00:34:23 in particular such incredible numbers of
00:34:23 --> 00:34:26 satellites. More than 100 for Jupiter, more
00:34:26 --> 00:34:27 than 200 for Saturn, currently known.
00:34:29 --> 00:34:32 Triton and our moon stand out as
00:34:32 --> 00:34:34 oddities because they don't quite fit either
00:34:34 --> 00:34:37 class. And for Earth's
00:34:37 --> 00:34:39 satellite, the moon, the origin of the moon
00:34:39 --> 00:34:41 seems to have been a giant impact, very
00:34:41 --> 00:34:43 different to either scenario. For the Regular
00:34:43 --> 00:34:46 irregular sate. But Triton around
00:34:46 --> 00:34:49 Neptune is really kind of weird.
00:34:49 --> 00:34:51 It's a moon that is 2 kilometres in
00:34:51 --> 00:34:54 diameter. It's a chunky
00:34:54 --> 00:34:57 boy. It is close enough in that it
00:34:57 --> 00:34:59 would normally be considered one of the
00:34:59 --> 00:35:01 regular satellites. And it is orbiting
00:35:01 --> 00:35:04 pretty much above Neptune's equator. But it's
00:35:04 --> 00:35:06 going around the wrong way. It's moving on a
00:35:06 --> 00:35:09 retrograde orbit when all of the other
00:35:09 --> 00:35:11 moons in the inner part of the Neptune system
00:35:11 --> 00:35:14 are going around on a programme red orbit. So
00:35:14 --> 00:35:16 there is no real possibility that Triton
00:35:16 --> 00:35:18 could have formed where it is today. And
00:35:18 --> 00:35:21 that's led for many decades
00:35:21 --> 00:35:23 people to speculate as to the origin of
00:35:23 --> 00:35:26 Triton. And typically the two main ideas
00:35:26 --> 00:35:29 are either that it was formed by a
00:35:29 --> 00:35:31 transeptunion object or an object like Pluto
00:35:32 --> 00:35:34 coming into the Neptune system, colliding
00:35:34 --> 00:35:36 with the moon, knocking that moon out of
00:35:36 --> 00:35:38 orbit, and Triton being captured by the
00:35:38 --> 00:35:40 exchange of angular momentum. That's not
00:35:40 --> 00:35:42 really the favourite idea though. The
00:35:42 --> 00:35:44 favoured idea is that you had a binary object
00:35:44 --> 00:35:47 a bit like Pluto and Charon, or
00:35:47 --> 00:35:50 many of the transeptunion objects are these
00:35:50 --> 00:35:53 quite wide binaries of objects with similar
00:35:53 --> 00:35:55 sizes. You had one of these
00:35:55 --> 00:35:57 objects in the early days of the solar
00:35:57 --> 00:35:59 system, came very close to Neptune and you
00:35:59 --> 00:36:01 had this three body encounter where you've
00:36:01 --> 00:36:04 got Triton and um, its companion,
00:36:04 --> 00:36:06 which was possibly another object the size of
00:36:06 --> 00:36:09 Pluto, bound together, coming
00:36:09 --> 00:36:11 so close to Neptune that Neptune tore the
00:36:11 --> 00:36:14 couple apart. As it tore them apart,
00:36:14 --> 00:36:16 Triton was moving around its shared centre of
00:36:16 --> 00:36:19 mass with its partner at such a speed that it
00:36:19 --> 00:36:21 was moving slower than the escape velocity of
00:36:21 --> 00:36:23 Neptune. So one component of the binary was
00:36:23 --> 00:36:25 flung out and the other was captured. And
00:36:25 --> 00:36:27 that's a way to slow something down enough
00:36:27 --> 00:36:30 that it can be captured. So you trap Triton
00:36:30 --> 00:36:33 into this orbit that is retrograde,
00:36:33 --> 00:36:35 going around the wrong way around that
00:36:35 --> 00:36:38 quickly damps down to become circular because
00:36:38 --> 00:36:40 of tidal effects with Neptune.
00:36:41 --> 00:36:43 Now that seems to be the storey of Triton.
00:36:43 --> 00:36:45 And what supports this is that the regular
00:36:45 --> 00:36:47 satellites of Neptune are uh, pretty small
00:36:47 --> 00:36:50 and insignificant and smaller and
00:36:50 --> 00:36:53 more insignificant than the similar satellite
00:36:53 --> 00:36:55 systems of the other planets. They seem to be
00:36:55 --> 00:36:56 a bit smaller and more weedy than you'd
00:36:56 --> 00:36:57 expect them to be.
00:36:57 --> 00:36:58 Andrew Dunkley: Yeah.
00:36:58 --> 00:37:00 Jonti Horner: So the idea is that the capture of a moon the
00:37:00 --> 00:37:03 size of Triton would be pretty dramatic
00:37:03 --> 00:37:05 and would destabilise the Neptune system.
00:37:06 --> 00:37:09 The outside Triton, Nereid, which was the
00:37:09 --> 00:37:11 second moon to be found around Neptune, is a
00:37:11 --> 00:37:14 really interesting one because it's a fair
00:37:14 --> 00:37:15 bit further out than Triton but it's moving
00:37:15 --> 00:37:18 on this really elongated prograde orbit.
00:37:18 --> 00:37:20 And um, it's thought that that may well have
00:37:20 --> 00:37:23 been initially a regular satellite
00:37:23 --> 00:37:25 that was destabilised by Triton and flung
00:37:25 --> 00:37:27 onto this longer orbit. It's not really
00:37:27 --> 00:37:30 considered an irregular moon even though it
00:37:30 --> 00:37:32 behaves a bit like when it's really close in.
00:37:32 --> 00:37:34 But the moon's closer to Neptune, Neptune
00:37:34 --> 00:37:37 than Triton, of which there are seven known.
00:37:37 --> 00:37:39 We've got Naiad, Thalassa, Despina,
00:37:39 --> 00:37:42 Galatea, Larissa, Hippocamp and Proteus.
00:37:43 --> 00:37:45 They're all relatively small.
00:37:45 --> 00:37:48 Proteus is the biggest at 420ks.
00:37:48 --> 00:37:51 The rest are not quite as big. And um, the
00:37:51 --> 00:37:53 only images we've got up close and personal
00:37:53 --> 00:37:55 come from the Voyager 2 spacecraft in 1989
00:37:55 --> 00:37:57 that show these moons to be a little bit
00:37:57 --> 00:38:00 irregular. And um, they're also a little bit
00:38:00 --> 00:38:03 more stirred up and agitated in orbital
00:38:03 --> 00:38:05 tilts and orbital eccentricities than in,
00:38:06 --> 00:38:08 I mean they're barely tilted and they're
00:38:08 --> 00:38:10 barely on non circular orbits but you'd
00:38:10 --> 00:38:12 expect them, if they were properly original
00:38:12 --> 00:38:14 regulars to be totally circular.
00:38:15 --> 00:38:18 So the idea is maybe Triton stir them up.
00:38:19 --> 00:38:21 Now one of the suggestions to explain why
00:38:21 --> 00:38:23 they're all so small is that Triton as it was
00:38:23 --> 00:38:26 captured and then at its migrated senses,
00:38:26 --> 00:38:27 stirred them up enough that the original
00:38:27 --> 00:38:30 moons were destroyed. It stirred them onto
00:38:30 --> 00:38:32 all bits that collided with each other that
00:38:32 --> 00:38:34 formed a new disc of material. Some was lost
00:38:34 --> 00:38:37 but new moons were born of the process. And
00:38:37 --> 00:38:39 uh, that's become kind of like the canonical
00:38:40 --> 00:38:42 understanding of what we think happened to
00:38:42 --> 00:38:44 Neptune's moons in the early days.
00:38:44 --> 00:38:46 And that all a lot of background brings us to
00:38:46 --> 00:38:48 the new observations. As I say, the
00:38:48 --> 00:38:51 observations we had before came from
00:38:51 --> 00:38:54 Voyager 2. That's the up close and personal
00:38:54 --> 00:38:56 we've got. But there's been some new work
00:38:56 --> 00:38:59 done using the James Webb Space Telescope to
00:38:59 --> 00:39:01 get data ah on three of these moons,
00:39:02 --> 00:39:05 Lara, Larissa and Galatea being two of them
00:39:05 --> 00:39:07 and I think the third one was um,
00:39:07 --> 00:39:10 possibly um, the next one out
00:39:10 --> 00:39:12 Proteus have to double cheque that but I
00:39:12 --> 00:39:14 think it was. And what they found though was
00:39:14 --> 00:39:17 when they looked at both Larissa and
00:39:17 --> 00:39:20 um, Galatea, they
00:39:20 --> 00:39:22 found clear signals of clay
00:39:22 --> 00:39:25 type minerals on the surfaces of these moons.
00:39:26 --> 00:39:28 Now that's really unexpected.
00:39:29 --> 00:39:31 Clay minerals form at uh,
00:39:31 --> 00:39:33 temperatures high enough for you to have
00:39:33 --> 00:39:36 liquid water because clays are formed in the
00:39:36 --> 00:39:38 presence of liquid water. And the surfaces of
00:39:38 --> 00:39:41 moons in Neptune's orbit are blooming cold.
00:39:41 --> 00:39:44 You know, they're like 180200 degrees below
00:39:44 --> 00:39:46 freezing, which is not where you'd expect to
00:39:46 --> 00:39:48 find liquid water. So what the authors are
00:39:48 --> 00:39:51 proposing is that, uh, the surfaces of these
00:39:51 --> 00:39:53 moons, which look, to be honest, more like
00:39:53 --> 00:39:54 the surfaces of asteroids in the asteroid
00:39:54 --> 00:39:57 belt, are actually made from
00:39:57 --> 00:40:00 material that was once deep in the interior
00:40:00 --> 00:40:03 of moons that formed before, that therefore
00:40:03 --> 00:40:05 got hot enough for liquid water to be
00:40:05 --> 00:40:07 present. And we've talked a lot before about
00:40:07 --> 00:40:09 other moons in the solar system that have
00:40:09 --> 00:40:11 subsurface oceans. So you have these
00:40:12 --> 00:40:13 first generation of moons with their
00:40:13 --> 00:40:16 subsurface oceans water present
00:40:16 --> 00:40:18 high enough temperatures for you to develop
00:40:18 --> 00:40:21 all these clay minerals. Then those moons get
00:40:21 --> 00:40:23 stirred up. When Triton is captured, there
00:40:23 --> 00:40:25 are collisions, they're smashed apart, and
00:40:25 --> 00:40:28 you create a disc of material around Neptune
00:40:28 --> 00:40:30 that contains the material from the old
00:40:30 --> 00:40:33 moons, clays and all. Then you form new
00:40:33 --> 00:40:35 moons, and some of those new moons have that
00:40:35 --> 00:40:38 clay material on their surface. So what's
00:40:38 --> 00:40:41 been argued essentially, is that this, uh,
00:40:41 --> 00:40:43 detection of clays in the last place you'd
00:40:43 --> 00:40:46 expect to find them is like the smoking gun.
00:40:46 --> 00:40:49 It's a clue that is telling us about the
00:40:49 --> 00:40:51 heritage of this system, about events that
00:40:51 --> 00:40:53 happened more than 4 billion years ago.
00:40:53 --> 00:40:55 And he's telling us about this kind of
00:40:55 --> 00:40:57 collisional history and the dramatic storey
00:40:57 --> 00:40:59 of the Neptune satellite system. I think it's
00:40:59 --> 00:41:02 an astonish, astonishingly cool result. And
00:41:02 --> 00:41:04 it's really cool for me, as someone who's
00:41:04 --> 00:41:06 read about Triton a lot in the past, thought
00:41:06 --> 00:41:08 about it a lot, that the ideas that were
00:41:08 --> 00:41:10 being put around even when I was a teenager
00:41:10 --> 00:41:12 and listening to talks at my local astronomy
00:41:12 --> 00:41:15 society about the disruption of the Neptune
00:41:15 --> 00:41:17 satellite system are suddenly finding a test,
00:41:17 --> 00:41:20 thanks to people using James Webb. So theory
00:41:20 --> 00:41:22 making a prediction, that prediction getting
00:41:22 --> 00:41:25 more support. I think this is really lovely.
00:41:25 --> 00:41:27 Andrew Dunkley: Yeah, it is. Uh, and it certainly shows the
00:41:27 --> 00:41:30 worth of James Webb. And very soon, the
00:41:30 --> 00:41:32 Nancy Grace Roman Observatory, we're, uh,
00:41:32 --> 00:41:33 going to learn more and more about some of
00:41:33 --> 00:41:36 those, um, not so deep
00:41:36 --> 00:41:39 mysteries in the scheme of things. It's not
00:41:39 --> 00:41:41 far away, Neptune, but, uh, it's far enough
00:41:41 --> 00:41:44 away to still be mysterious in many
00:41:44 --> 00:41:46 ways. We really need to send a mission out
00:41:46 --> 00:41:48 there again soon, don't we?
00:41:48 --> 00:41:50 Jonti Horner: I was just thinking that there's been a lot
00:41:50 --> 00:41:53 of talk over the last decade
00:41:53 --> 00:41:55 or so, really, with solar system astronomers,
00:41:55 --> 00:41:56 astronomers getting more and more
00:41:56 --> 00:41:59 enthusiastic about the idea of sending new
00:41:59 --> 00:42:02 spacecraft out to Uranus and Neptune. Um,
00:42:02 --> 00:42:04 there's always debate when
00:42:05 --> 00:42:07 it's time to pitch new missions for NASA, of
00:42:07 --> 00:42:10 the different scales people put in competing
00:42:10 --> 00:42:13 proposals. And I know at the Last round there
00:42:13 --> 00:42:14 were a number of proposals of missions to
00:42:14 --> 00:42:16 Venus because we've not been there for a long
00:42:16 --> 00:42:18 time in terms of the Americans sent me. I
00:42:18 --> 00:42:21 know Japan had a fabulous orbit, are doing
00:42:21 --> 00:42:23 some great work there. There were also some
00:42:23 --> 00:42:26 really strong proposals of missions
00:42:26 --> 00:42:28 to Uranus and Neptune. I think this was a
00:42:28 --> 00:42:31 kind of medium sized stuff, so not Nancy
00:42:31 --> 00:42:34 Grace Roman pots of money, but more the $400
00:42:34 --> 00:42:36 million rather than $4 billion price
00:42:36 --> 00:42:39 missions. And in the last round I think the
00:42:39 --> 00:42:41 Venus missions won. But there is this growing
00:42:42 --> 00:42:45 longing to get missions to go back there
00:42:45 --> 00:42:47 and actually have orbiters because both
00:42:47 --> 00:42:49 Uranus and Neptune, the only up close and
00:42:49 --> 00:42:51 personal we've had with them were the Voyager
00:42:51 --> 00:42:54 spacecraft that launched in 1979.
00:42:55 --> 00:42:57 You know, launched back when I was one year
00:42:57 --> 00:42:57 old.
00:42:58 --> 00:42:58 Andrew Dunkley: Yeah.
00:42:58 --> 00:43:01 Jonti Horner: And flew past Uranus and Neptune. It was only
00:43:01 --> 00:43:03 Voyager 2 that got there. Voyager 1 went off
00:43:03 --> 00:43:05 on a different journey. So we've had one
00:43:05 --> 00:43:07 spacecraft that flew past faster than a
00:43:07 --> 00:43:09 speeding bullet, that spent less than a day
00:43:09 --> 00:43:11 within good imaging distance of these
00:43:11 --> 00:43:14 planets, return really tantalising
00:43:14 --> 00:43:17 information and then departed. And we've
00:43:17 --> 00:43:19 seen how much we learned from Galileo at
00:43:19 --> 00:43:22 Jupiter, from Cassini at Saturn, from Juno at
00:43:22 --> 00:43:24 Jupiter. So there's this growing body of
00:43:24 --> 00:43:26 scientists who are desperate to see this
00:43:26 --> 00:43:29 happen. Won't be cheap. And the other thing
00:43:29 --> 00:43:31 is, if such a mission was approved like next
00:43:31 --> 00:43:34 week, probably wouldn't launch for the best
00:43:34 --> 00:43:36 part of a decade and it would take the best
00:43:36 --> 00:43:38 part of a decade to get there. So it's the
00:43:38 --> 00:43:39 kind of thing where we're talking now. And
00:43:39 --> 00:43:42 I'll probably be retarded, retired when these
00:43:42 --> 00:43:43 spacecraft get there.
00:43:43 --> 00:43:44 Andrew Dunkley: I don't want to think about it.
00:43:47 --> 00:43:49 I don't think I'll be beyond retired.
00:43:49 --> 00:43:51 Jonti Horner: Let's just say that the sooner the better
00:43:51 --> 00:43:52 that we get there then.
00:43:53 --> 00:43:55 Andrew Dunkley: Yes, indeed, great storey. You can read
00:43:55 --> 00:43:58 about it online. Um, plenty of, uh, platforms
00:43:58 --> 00:44:01 have got storeys about uh, Neptune
00:44:01 --> 00:44:03 satellites. You can read the scientific paper
00:44:03 --> 00:44:06 in detail at the journal Science
00:44:06 --> 00:44:08 Advances. That brings us to the end.
00:44:08 --> 00:44:09 Jonty, thank you very much.
00:44:10 --> 00:44:11 Jonti Horner: That's an absolute pleasure. Thank you for
00:44:11 --> 00:44:12 having me.
00:44:12 --> 00:44:14 Andrew Dunkley: Always a pleasure. Professor, uh, John de
00:44:14 --> 00:44:16 Horner, professor of Astrophysics at the
00:44:17 --> 00:44:19 University of Southern Queensland. Between
00:44:19 --> 00:44:21 episodes, don't forget to visit our website
00:44:21 --> 00:44:24 for um, things to see and do like
00:44:24 --> 00:44:26 you can, um, send us messages or questions
00:44:26 --> 00:44:28 through the Ask me anything button at the
00:44:28 --> 00:44:31 top. It's labelled ama. You can sign up for
00:44:31 --> 00:44:33 the Astronomy AstroDailyPod feed. Uh, please
00:44:33 --> 00:44:35 leave reviews about the podcast wherever you
00:44:35 --> 00:44:38 listen to us and visit, uh, the Space
00:44:38 --> 00:44:40 Nuts shop while you're there.
00:44:40 --> 00:44:43 Um, Father's Day in Australia coming up
00:44:43 --> 00:44:45 soon. That's, you know, you might find
00:44:45 --> 00:44:46 something good in there. A couple of good
00:44:46 --> 00:44:48 books have been released lately. You might
00:44:48 --> 00:44:51 like the little cat, maybe. Uh,
00:44:51 --> 00:44:54 and, uh, thanks to Huw in the studio couldn't
00:44:54 --> 00:44:56 be with us today. He was actually driving
00:44:56 --> 00:44:59 over to, um, get to the studio
00:44:59 --> 00:45:02 for us today. But then, uh, as was
00:45:02 --> 00:45:05 the case with Neptune, uh, he got hit by a
00:45:05 --> 00:45:07 Mitsubishi Triton and that was the end of
00:45:07 --> 00:45:09 that. Uh, and from me, Andrew Dunkley. Oh,
00:45:09 --> 00:45:12 he's actually okay, you know, he just
00:45:12 --> 00:45:13 couldn't make it. And from me, Andrew
00:45:13 --> 00:45:14 Dunkley. Thanks for your company. We'll catch
00:45:14 --> 00:45:17 you on the next episode of Space Nuts. Bye.
00:45:17 --> 00:45:20 Bye. You've been listening to the
00:45:20 --> 00:45:20 Space Nuts
00:45:20 --> 00:45:23 Jonti Horner: podcast, available at
00:45:23 --> 00:45:25 Apple Podcasts, Spotify,
00:45:25 --> 00:45:28 iHeartRadio or your favourite podcast
00:45:28 --> 00:45:30 player. You can also stream on
00:45:30 --> 00:45:32 demand@bytes.com.
00:45:32 --> 00:45:34 Andrew Dunkley: this has been another quality podcast
00:45:34 --> 00:45:36 production from bytes.com.
00:45:36 --> 00:45:37 Jonti Horner: um,