00:00:00 --> 00:00:03 Andrew Dunkley: Hello again. This is Space Nuts. It's a Q and
00:00:03 --> 00:00:05 A edition. This is where we take questions
00:00:05 --> 00:00:08 from the audience, throw them in the bin and
00:00:08 --> 00:00:10 discuss other things amongst ourselves. No,
00:00:10 --> 00:00:12 we do answer questions from the audience and
00:00:12 --> 00:00:14 we've got a bunch. Um, we've got a question
00:00:14 --> 00:00:17 about the uh, naming of the
00:00:17 --> 00:00:20 increase in the expansion of the universe
00:00:20 --> 00:00:23 rate. Although last episode, if you
00:00:23 --> 00:00:25 were listening, that might not be happening,
00:00:25 --> 00:00:27 but we will still try and tackle it. Uh,
00:00:27 --> 00:00:30 there's a question about space elevators.
00:00:30 --> 00:00:32 We've got uh, a question about an object that
00:00:32 --> 00:00:34 has been getting a lot of attention
00:00:34 --> 00:00:37 TOI6894B. And
00:00:37 --> 00:00:39 a very different kind of question, I
00:00:39 --> 00:00:42 will say, uh, regarding Gale Crater.
00:00:43 --> 00:00:45 That's all coming up on this, uh, edition of
00:00:45 --> 00:00:48 space nuts. 15 seconds. Guidance is
00:00:48 --> 00:00:51 internal. 10, 9.
00:00:51 --> 00:00:53 Ignition sequence start.
00:00:53 --> 00:00:55 Jonti Horner: Space nuts. 5, 4, 3, 2.
00:00:55 --> 00:00:58 Andrew Dunkley: 1. 2, 3, 4, 5, 5, 4, 3,
00:00:58 --> 00:01:01 2, 1. Space nuts. Astronauts report
00:01:01 --> 00:01:04 it feels good. He's back again for
00:01:04 --> 00:01:06 more. He is Jonti Horner, professor of
00:01:06 --> 00:01:08 Astrophysics at the University of Southern
00:01:08 --> 00:01:10 Queensland. Jonti, hello.
00:01:10 --> 00:01:12 Jonti Horner: Good afternoon. How are you going?
00:01:12 --> 00:01:14 Andrew Dunkley: I'm well, I'm very well.
00:01:14 --> 00:01:17 Uh, we've got a lot of questions and this
00:01:17 --> 00:01:19 very first one, we'll jump straight in. Comes
00:01:19 --> 00:01:22 from Rusty in Donnybrook in Western
00:01:22 --> 00:01:22 Australia.
00:01:22 --> 00:01:24 Andrew Dunkley: Johnny and Andrew. G'.
00:01:24 --> 00:01:24 Jonti Horner: Day.
00:01:24 --> 00:01:26 Andrew Dunkley: It's Rusty in Donnybrook and I'm wondering
00:01:26 --> 00:01:29 what the, the term um, for
00:01:30 --> 00:01:32 an increase in the acceleration
00:01:32 --> 00:01:35 rate for the expansion of the universe is.
00:01:35 --> 00:01:37 We've known about. Well we've had this
00:01:37 --> 00:01:39 concept for quite a few years now. And
00:01:39 --> 00:01:42 recently we um, we're now looking at
00:01:42 --> 00:01:44 a reduction in the acceleration of the
00:01:44 --> 00:01:46 expansion rate of the universe as well. So
00:01:46 --> 00:01:49 there's a positive and a negative aspect to
00:01:49 --> 00:01:51 this. And um, since we've had all this time,
00:01:51 --> 00:01:53 someone may have come up with ah, a better
00:01:53 --> 00:01:56 term than jolt or jerk, which seem
00:01:56 --> 00:01:59 to apply to very short term changes
00:01:59 --> 00:02:02 and not very gradual changes that
00:02:02 --> 00:02:05 we theorize uh, in the expansion of the
00:02:05 --> 00:02:07 universe. Thank you.
00:02:07 --> 00:02:10 Andrew Dunkley: Thanks Rusty. Always good to hear from you.
00:02:10 --> 00:02:11 Uh, he's always got a
00:02:12 --> 00:02:15 curveball type question, has Rusty. Although
00:02:15 --> 00:02:16 we might have been able to curve the ball
00:02:16 --> 00:02:19 back to him because last uh, episode we
00:02:19 --> 00:02:21 were talking about this very subject, the
00:02:21 --> 00:02:24 expand, increasing rate of the
00:02:24 --> 00:02:26 expansion of the universe. And uh, he wants
00:02:26 --> 00:02:29 to know what it should be called. But um, the
00:02:29 --> 00:02:31 expansion of the universe theory might be
00:02:31 --> 00:02:33 tipped on its head because of the research we
00:02:33 --> 00:02:35 were talking about last time. So if you
00:02:35 --> 00:02:37 haven't listened to the previous
00:02:37 --> 00:02:40 episode573, go back and have a Listen to
00:02:40 --> 00:02:42 the last story because it, it's
00:02:42 --> 00:02:45 suggesting that, uh, things may not be as
00:02:45 --> 00:02:46 they seem. Jonti.
00:02:47 --> 00:02:49 Jonti Horner: Absolutely. And it's, you know, this advert
00:02:49 --> 00:02:51 brought to you by the developing nature of
00:02:51 --> 00:02:54 science. Essentially it, uh, is how science
00:02:54 --> 00:02:56 evolves. You know, we get new observations
00:02:56 --> 00:02:58 and we revisit our theories. It's a really
00:02:58 --> 00:03:00 good question and it's a really good point. I
00:03:00 --> 00:03:02 have never actually heard any
00:03:02 --> 00:03:05 nickname or any kind of easy roll off
00:03:05 --> 00:03:07 the tongue phrase to talk about the
00:03:07 --> 00:03:09 accelerating expansion of the universe.
00:03:10 --> 00:03:12 Cosmologists talk about things in the context
00:03:12 --> 00:03:14 of the lambda CDM model. And, um, I don't
00:03:14 --> 00:03:16 really understand what that is because I'm
00:03:16 --> 00:03:18 not a cosmologist, but that is not an easy
00:03:18 --> 00:03:21 roll off the tongue nickname. Now, if you go
00:03:21 --> 00:03:23 back to the very, very, very, very early
00:03:23 --> 00:03:26 youth of the universe, there was
00:03:26 --> 00:03:29 a period where there was this incredibly
00:03:29 --> 00:03:32 accelerated expansion that is hypothesized
00:03:32 --> 00:03:34 called inflation. And, um, that was
00:03:35 --> 00:03:38 very, very, very early on. That's called the
00:03:38 --> 00:03:39 inflationary period. That's a little bit
00:03:39 --> 00:03:42 different. What Russ is talking about here is
00:03:42 --> 00:03:45 the, uh, evidence which won the Nobel
00:03:45 --> 00:03:48 Prize in 1998, I think, for the fact that,
00:03:48 --> 00:03:51 that the universe may be expanding at an
00:03:51 --> 00:03:53 accelerating rate. So in other words, the
00:03:53 --> 00:03:54 expansion is getting quicker rather than
00:03:54 --> 00:03:57 slowing down. And if gravity was winning,
00:03:57 --> 00:03:59 you'd expect the expansion to slow down over
00:03:59 --> 00:04:01 time as gravity pulls back on the expansion.
00:04:01 --> 00:04:04 So this was the great evidence for the
00:04:04 --> 00:04:05 existence of dark energy, which people
00:04:05 --> 00:04:08 hypothesize contributes something like
00:04:08 --> 00:04:11 68% of all that there is in the universe.
00:04:11 --> 00:04:13 It's basically we're a dark energy universe
00:04:13 --> 00:04:15 with a fair chunk of dark matter and a tiny
00:04:15 --> 00:04:17 little bit of normal matter on the side, like
00:04:17 --> 00:04:19 less than 2%. That,
00:04:20 --> 00:04:22 as we talked about in the previous episode,
00:04:22 --> 00:04:24 may be a paradigm that is about to change.
00:04:24 --> 00:04:26 There's growing evidence that the universe is
00:04:26 --> 00:04:29 perhaps a bit more complex than that. But in
00:04:29 --> 00:04:31 terms of Rusty's question, I have never come
00:04:31 --> 00:04:34 across a simple term or nickname
00:04:34 --> 00:04:37 or something like that for this theory.
00:04:37 --> 00:04:38 People just talk about the accelerating
00:04:38 --> 00:04:41 expansion rate of the universe. So
00:04:41 --> 00:04:43 unfortunately, Rusty, I can't help you there.
00:04:43 --> 00:04:45 To the best of my knowledge, there is no
00:04:45 --> 00:04:47 really snappy roll off your tongue thing. I.
00:04:48 --> 00:04:49 The model that tries to explain it, like,
00:04:49 --> 00:04:52 say, is a lambda CDM model. But that is
00:04:52 --> 00:04:54 not a snappy, um,
00:04:54 --> 00:04:57 public article, BBC documentary
00:04:57 --> 00:05:00 type name that will capture people's
00:05:00 --> 00:05:01 imaginations. That's just a working
00:05:02 --> 00:05:04 terminology in the industry kind of thing.
00:05:04 --> 00:05:04 Yeah.
00:05:04 --> 00:05:06 Andrew Dunkley: Well, while you've been talking, I asked
00:05:06 --> 00:05:09 Chatgpt what we
00:05:09 --> 00:05:11 should call it. It came up with a whole
00:05:11 --> 00:05:14 bunch, uh, accelerating universe hypothesis,
00:05:15 --> 00:05:17 uh, cosmic expansion theory, uh,
00:05:17 --> 00:05:20 inflation continuum theory, dark energy
00:05:20 --> 00:05:22 paradigm. You use that word. Uh,
00:05:23 --> 00:05:26 that's a more scientific style. But uh, it
00:05:26 --> 00:05:28 came up with some, uh, conceptual names. The
00:05:28 --> 00:05:31 great unbinding, uh,
00:05:31 --> 00:05:32 external expansion
00:05:33 --> 00:05:36 hypothesis, uh, runaway cosmos
00:05:36 --> 00:05:39 model, uh, the horizon drift
00:05:39 --> 00:05:41 theory. I like that one. Metric
00:05:41 --> 00:05:44 unfolding principle, the lambda drive and the
00:05:44 --> 00:05:47 everflight theory. That's what ChatGPT's come
00:05:47 --> 00:05:49 up with. Probably just found stuff that
00:05:49 --> 00:05:50 people have published.
00:05:50 --> 00:05:51 Jonti Horner: I think a lot of those are things that are
00:05:51 --> 00:05:53 linked to this but are other hypotheses and
00:05:53 --> 00:05:56 stuff like that. Yeah, I mean I have to admit
00:05:56 --> 00:05:58 that I didn't really want to Google things
00:05:58 --> 00:06:00 there because I wasn't all that keen on
00:06:00 --> 00:06:01 seeing the Google autocorrect coming back
00:06:01 --> 00:06:03 saying, did you mean expanding wasteland?
00:06:06 --> 00:06:08 Andrew Dunkley: Yeah, it does come up with some. Really what
00:06:08 --> 00:06:10 I hate is when I know exactly what I'm
00:06:10 --> 00:06:11 searching for. I put it in, I've uh, spelled
00:06:11 --> 00:06:13 it right and an autocorrect and finds me
00:06:13 --> 00:06:16 something else. Yeah, that's not what I asked
00:06:16 --> 00:06:18 for. I told you to look for, you know,
00:06:18 --> 00:06:21 lemonade, not lemons. Anyway,
00:06:22 --> 00:06:24 thanks Rusty. Uh, maybe you've got a name you
00:06:24 --> 00:06:26 can send through to us or maybe um, somebody
00:06:26 --> 00:06:28 could pose the question on the Facebook group
00:06:28 --> 00:06:31 or the podcast group on Facebook and uh,
00:06:31 --> 00:06:34 come up with some names. I'd be interested to
00:06:34 --> 00:06:36 see what you think of.
00:06:36 --> 00:06:38 Uh, our next question comes from Barry. Uh,
00:06:38 --> 00:06:41 Barry said, I, uh, recently read a sci fi
00:06:41 --> 00:06:44 book called First Ascent. Based on a space
00:06:44 --> 00:06:46 element. The elevator had six stations, one
00:06:46 --> 00:06:49 being Earth, uh, two at 300 kilometers, five
00:06:49 --> 00:06:52 at 6200 kilometers and six being
00:06:52 --> 00:06:53 geostationary orbit at
00:06:53 --> 00:06:56 35 kilometers. I
00:06:56 --> 00:06:58 know the International Space Station's about
00:06:58 --> 00:07:01 400 kilometers and the crew are in free
00:07:01 --> 00:07:04 fall. This is due to the forward motion of
00:07:04 --> 00:07:06 the iss, which is constantly falling and is
00:07:06 --> 00:07:09 in orbit. In the book they discuss that at
00:07:09 --> 00:07:12 Station 1 at 300 km the travellers are still
00:07:12 --> 00:07:15 at about 1G. Station 5, uh,
00:07:15 --> 00:07:18 at 6200 km they're at 1 quarter G,
00:07:18 --> 00:07:21 they're on the moon, they be at 1/6 and free
00:07:21 --> 00:07:24 fall, weightless, is at station 6,
00:07:24 --> 00:07:27 35 and a bit kilometers. Can you
00:07:27 --> 00:07:30 discuss with accuracy of feeling
00:07:30 --> 00:07:33 gravity if and when a space elevator is
00:07:33 --> 00:07:35 built? Of course, this is totally
00:07:35 --> 00:07:37 hypothetical for at least the next few
00:07:37 --> 00:07:40 hundred or thousand years. Yes it is. It's
00:07:40 --> 00:07:43 not something we can do yet. And even if we
00:07:43 --> 00:07:46 could, I don't know if it would be the
00:07:46 --> 00:07:49 Logical way to do things. But you know, we
00:07:49 --> 00:07:50 don't know what reasons in the future we
00:07:50 --> 00:07:53 might need one. So um, we'll just leave it
00:07:53 --> 00:07:54 hanging in the air. Boom.
00:07:54 --> 00:07:54 Jonti Horner: Boom.
00:07:55 --> 00:07:57 Andrew Dunkley: Um, so, uh, yeah. So can you discuss the
00:07:57 --> 00:08:00 accuracy of feeling gravity if and when a
00:08:00 --> 00:08:01 space.
00:08:01 --> 00:08:02 Jonti Horner: Uh, elevator is built?
00:08:03 --> 00:08:05 Yeah, it's a fabulous question. And it does
00:08:05 --> 00:08:08 sound like this book is hard sci fi in
00:08:08 --> 00:08:10 the sense that it's based on real world
00:08:10 --> 00:08:12 physics is what I'd say. It sounds like the
00:08:12 --> 00:08:14 numbers are right to me. Now the argument is
00:08:14 --> 00:08:16 that a space elevator, once you can get it
00:08:16 --> 00:08:18 built, it's an incredibly challenging thing
00:08:18 --> 00:08:20 to do beyond us at the minute. But once
00:08:20 --> 00:08:23 you've got it, it's suddenly it makes it much
00:08:23 --> 00:08:25 easier to access space. And part of the
00:08:25 --> 00:08:28 argument there is that we will be extracting
00:08:28 --> 00:08:31 resources off Earth. And so it's likely that
00:08:31 --> 00:08:32 there'll be more stuff coming down the
00:08:32 --> 00:08:34 elevator than going up. So effectively you
00:08:34 --> 00:08:37 can ride up for free, just, you know, as a
00:08:37 --> 00:08:39 side effect of it. So it's one of those
00:08:39 --> 00:08:42 things that has become a staple of kind of
00:08:42 --> 00:08:44 relatively near futureish science fiction.
00:08:45 --> 00:08:47 The numbers here about the acceleration that
00:08:47 --> 00:08:50 you'd feel are accurate. So there's two ways
00:08:50 --> 00:08:52 that you can get gravity if you're on a space
00:08:52 --> 00:08:55 elevator. One is that you would feel
00:08:55 --> 00:08:57 a pseudo gravity based on the acceleration
00:08:58 --> 00:09:01 of the lift going upwards. And you
00:09:01 --> 00:09:04 get this when your lift goes up or when it
00:09:04 --> 00:09:06 falls. If you're in a building that has one
00:09:06 --> 00:09:08 of those ultra fast lifts, you feel a little
00:09:08 --> 00:09:09 bit more weightless. If it's going down, you
00:09:09 --> 00:09:11 feel a little bit heavier when it's pulling
00:09:11 --> 00:09:13 up initially because the flow will be
00:09:13 --> 00:09:16 accelerating up to meet you or
00:09:16 --> 00:09:18 accelerating down away from you. And that
00:09:18 --> 00:09:21 will mean that you will get a change to the
00:09:21 --> 00:09:23 gravity you would otherwise feel if you were
00:09:23 --> 00:09:26 stationary at that altitude. So
00:09:26 --> 00:09:29 some sci fi books I've seen with kind of far
00:09:29 --> 00:09:31 future type technology have
00:09:32 --> 00:09:35 your space elevator, uh, able to accelerate,
00:09:35 --> 00:09:38 ah, or in excess of 1g, very hard
00:09:38 --> 00:09:40 acceleration. And what they do is they
00:09:40 --> 00:09:42 accelerate slowly going up through the
00:09:42 --> 00:09:44 atmosphere and then speed up once you're in
00:09:44 --> 00:09:46 vacuum with the acceleration
00:09:46 --> 00:09:49 offsetting the drop in gravity you get as you
00:09:49 --> 00:09:51 get higher, keeping you at a comfortable
00:09:51 --> 00:09:52 level of gravity. And then when you're
00:09:52 --> 00:09:55 halfway to the end point, it turns around,
00:09:55 --> 00:09:57 you have a brief period of pseudo
00:09:57 --> 00:09:59 weightlessness and then you accelerate in the
00:09:59 --> 00:10:01 other direction, slow down. So that's one way
00:10:01 --> 00:10:03 that you could get kind of constant gravity
00:10:03 --> 00:10:05 throughout almost the entire trip. And that
00:10:05 --> 00:10:07 will get you to your uh, End point pretty
00:10:07 --> 00:10:10 quickly. So if you're accelerating at 1G, you
00:10:10 --> 00:10:11 actually accelerate very quickly. And that's
00:10:11 --> 00:10:12 why you wait till you're out of the
00:10:12 --> 00:10:15 atmosphere to do that. But the other thing
00:10:15 --> 00:10:17 is, as you ride up on a space elevator, the
00:10:17 --> 00:10:20 higher you get, you will still feel gravity
00:10:20 --> 00:10:22 pulling you down through the soles of your
00:10:22 --> 00:10:25 feet, but the strength of the gravitational
00:10:25 --> 00:10:27 pull you feel will weaken. Now,
00:10:27 --> 00:10:30 when you're at the end point, which is
00:10:30 --> 00:10:33 a space station in geostationary orbit, you
00:10:33 --> 00:10:35 are moving around the Earth, ah, at orbital
00:10:35 --> 00:10:38 velocity. And, um, the space station around
00:10:38 --> 00:10:39 you is moving around the Earth at orbital
00:10:39 --> 00:10:42 velocity. So that's why you'd be weightless,
00:10:42 --> 00:10:44 because you're accelerating at exactly the
00:10:44 --> 00:10:46 same rate as your surroundings.
00:10:47 --> 00:10:50 So compared to you, there is no acceleration
00:10:50 --> 00:10:51 pulling you down because the flow's falling
00:10:51 --> 00:10:54 away at exactly the speed that you're falling
00:10:54 --> 00:10:56 down effectively. So that's what you'd
00:10:56 --> 00:10:58 experience very briefly if you were in an
00:10:58 --> 00:11:01 elevator on Earth and the wires were cut when
00:11:01 --> 00:11:03 you started to fall, you'd be weightless, but
00:11:03 --> 00:11:05 you wouldn't be enjoying the experience. No,
00:11:05 --> 00:11:06 not much worrying about what happens at the
00:11:06 --> 00:11:09 bottom. Although, thanks to a very, very
00:11:09 --> 00:11:12 silly TV series that's quite swearing
00:11:12 --> 00:11:14 offensive called Archer, my understanding is
00:11:14 --> 00:11:17 that lifts, uh, have been designed in such a
00:11:17 --> 00:11:19 way that if the cables break, there are
00:11:19 --> 00:11:21 safety mechanisms in so you won't just splat
00:11:21 --> 00:11:23 at the bottom. There was a whole episode
00:11:23 --> 00:11:24 based where they were stuck in the lift and
00:11:24 --> 00:11:26 they were worried about that. It's bizarre
00:11:26 --> 00:11:28 what you learn from random TV cartoons.
00:11:28 --> 00:11:31 Anyway, so you have,
00:11:31 --> 00:11:34 at the upper limit, effectively
00:11:34 --> 00:11:37 zero G, you are weightless. You're actually,
00:11:37 --> 00:11:39 you are experiencing the Earth's gravity, but
00:11:39 --> 00:11:40 so is the space station around you. When
00:11:40 --> 00:11:42 you're falling together, just like mentioned
00:11:42 --> 00:11:44 with the International Space Station
00:11:45 --> 00:11:48 at, uh, that point, if you had some way of
00:11:49 --> 00:11:51 sitting stationary in space, so in other
00:11:51 --> 00:11:54 words, you were not orbiting the Earth, you
00:11:54 --> 00:11:56 were motionless, but you had a rocket holding
00:11:56 --> 00:11:58 you up. You would still feel the Earth's
00:11:58 --> 00:12:00 gravity pulling you down because the rocket
00:12:00 --> 00:12:02 would be pushing up against your feet
00:12:02 --> 00:12:04 essentially, and you'd feel the strength of
00:12:04 --> 00:12:06 gravity there. You're, uh, at
00:12:06 --> 00:12:09 36 kilometers, which means you're 42
00:12:09 --> 00:12:11 kilometers from the center of the earth,
00:12:11 --> 00:12:13 which means you're seven times further from
00:12:13 --> 00:12:15 the middle of the Earth, uh, than we are
00:12:15 --> 00:12:17 here. The strength of gravity falls off as 1
00:12:17 --> 00:12:20 over distance squared. So you'd feel about 1
00:12:20 --> 00:12:23 50th of a G there. So if
00:12:23 --> 00:12:25 you were able to sit still rather than
00:12:25 --> 00:12:26 falling with the Space station, you would
00:12:26 --> 00:12:28 feel a little bit of gravity there, but it
00:12:28 --> 00:12:31 wouldn't be that intense at the lower
00:12:31 --> 00:12:34 altitudes. The effect
00:12:34 --> 00:12:36 is dominated not by your rotation movement,
00:12:36 --> 00:12:38 because you're going much slower than orbital
00:12:38 --> 00:12:41 speed, but by the fact that gravity is
00:12:41 --> 00:12:43 pulling you down, but the
00:12:43 --> 00:12:45 lift is being winched upwards.
00:12:46 --> 00:12:49 So if you lifted your space elevator up and
00:12:49 --> 00:12:52 you stopped at one of these stops, and that's
00:12:52 --> 00:12:54 why they talk about the stops, I suspect if
00:12:54 --> 00:12:57 you stopped at 300 km at a station just above
00:12:57 --> 00:12:59 the atmosphere, attached to the tether,
00:12:59 --> 00:13:02 moving around at the same speed the Earth's
00:13:02 --> 00:13:05 rotating underneath you, you'd feel an
00:13:05 --> 00:13:07 acceleration due to gravity that is a little
00:13:07 --> 00:13:08 bit smaller than that we feel at the surface
00:13:08 --> 00:13:11 of the Earth. Now, if you're at the top of
00:13:11 --> 00:13:13 Mount Everest, technically you feel a
00:13:13 --> 00:13:14 slightly lower acceleration due to gravity
00:13:14 --> 00:13:17 than you do at the sea level because
00:13:17 --> 00:13:19 you're further from the center of the Earth.
00:13:19 --> 00:13:22 So that one over R squared component in
00:13:22 --> 00:13:25 the acceleration due to gravity equation is
00:13:25 --> 00:13:27 a slightly bigger number on the R squared,
00:13:27 --> 00:13:29 which means your acceleration due to gravity
00:13:29 --> 00:13:31 is a slightly smaller number. But that's
00:13:31 --> 00:13:33 imperceptible to humans. But we can measure
00:13:33 --> 00:13:35 it with instrumentation. That, incidentally,
00:13:35 --> 00:13:38 is why, if you really wanted to, to,
00:13:38 --> 00:13:41 um, lose weight, um, but
00:13:41 --> 00:13:43 you're being lazy. If you want to get weighed
00:13:43 --> 00:13:45 in the place where you will wear the least on
00:13:45 --> 00:13:47 the Earth, you go to the top of that mountain
00:13:47 --> 00:13:49 near the equator. Is it anaconda? I think it
00:13:49 --> 00:13:52 is. Which is a point on the Earth that is
00:13:52 --> 00:13:54 furthest from the Earth's core. Because
00:13:54 --> 00:13:55 you've got the bulge of the Earth's equator
00:13:55 --> 00:13:58 on top of the height of the mountain.
00:13:59 --> 00:14:00 And you will feel a slightly smaller
00:14:00 --> 00:14:02 acceleration due to gravity there because
00:14:02 --> 00:14:04 you're further from the Earth's core. So at
00:14:04 --> 00:14:07 300km up, you've only changed your distance
00:14:07 --> 00:14:10 from the center of the earth by about 5%. And
00:14:10 --> 00:14:11 so you've probably changed the acceleration
00:14:11 --> 00:14:13 due to gravity by less than 10%. It's
00:14:13 --> 00:14:15 probably enough that you'd be able to notice
00:14:15 --> 00:14:17 it. Walking around would feel slightly
00:14:17 --> 00:14:20 unusual, but it wouldn't be a problem. The
00:14:20 --> 00:14:22 station number five that is mentioned here,
00:14:22 --> 00:14:25 at 6200km, that means
00:14:25 --> 00:14:27 you're nearly twice as far away from the
00:14:27 --> 00:14:29 center of the Earth now as we are on the
00:14:29 --> 00:14:30 surface of the Earth. Surface of the Earth,
00:14:30 --> 00:14:33 we're about 6 kilometers from the middle.
00:14:34 --> 00:14:35 Varies a little depending on your altitude
00:14:35 --> 00:14:37 above sea level and where you are on the
00:14:37 --> 00:14:39 globe. Yeah. Add another 6200
00:14:39 --> 00:14:42 km, you've effectively doubled the distance,
00:14:42 --> 00:14:45 which means 1 upon r squared is 1 over 2
00:14:45 --> 00:14:48 times 1 over 2 is 1 over 4. So the
00:14:48 --> 00:14:50 acceleration is a quarter of a g. So we've
00:14:50 --> 00:14:52 dropped the strength of gravitude field by a
00:14:52 --> 00:14:54 factor of four. And at that point that is
00:14:54 --> 00:14:57 hugely noticeable. It's a little bit stronger
00:14:57 --> 00:14:59 gravity than you'd have on the moon, but not
00:14:59 --> 00:15:02 by much. Now, I guess this is the kind of
00:15:02 --> 00:15:03 thing where you could, if you were sending
00:15:03 --> 00:15:06 people to Mars and you wanted them to
00:15:06 --> 00:15:09 experience Martian gravity and see if they
00:15:09 --> 00:15:11 could cope with it, you know, you had a
00:15:11 --> 00:15:13 training and a testing program and anybody
00:15:13 --> 00:15:15 that got too travel sick or whatever and
00:15:15 --> 00:15:17 couldn't adapt was bumped out of the program.
00:15:17 --> 00:15:19 What you do is you take this space elevator,
00:15:20 --> 00:15:22 you figure out exactly at what height above
00:15:22 --> 00:15:24 the ground, you would emulate Martian gravity
00:15:24 --> 00:15:26 perfectly and you build a training station
00:15:26 --> 00:15:28 there. Because at the end of the day, if
00:15:28 --> 00:15:29 you've got a space elevator, you know, you
00:15:29 --> 00:15:32 may as well put an extra level on it. Um, and
00:15:32 --> 00:15:34 that way you can train people up for Mars.
00:15:34 --> 00:15:35 And I could almost imagine a future where
00:15:35 --> 00:15:37 they have one for the moon as well. You know,
00:15:37 --> 00:15:39 go up there, spend a few weeks training in
00:15:39 --> 00:15:41 lunar gravity and see if you can hack it on
00:15:41 --> 00:15:43 the surface of the M moon. And anybody who
00:15:43 --> 00:15:45 can't, no shame. We all have slightly
00:15:45 --> 00:15:47 different balance systems and all the rest of
00:15:47 --> 00:15:50 it, if you can't adjust, that's fine, you can
00:15:50 --> 00:15:52 work on Earth, no problem. But so it
00:15:52 --> 00:15:55 does sound like the science in this
00:15:55 --> 00:15:58 book is robust. In other words, it's hard,
00:15:58 --> 00:15:59 hard sci fi.
00:15:59 --> 00:16:01 It's based on our current understanding of
00:16:01 --> 00:16:03 physics and that's how it would work on space
00:16:03 --> 00:16:05 elevator. So hopefully that makes sense. And
00:16:05 --> 00:16:08 it is a really good example of how you can
00:16:08 --> 00:16:10 use a science fiction book to t to teach
00:16:10 --> 00:16:11 people science fact.
00:16:12 --> 00:16:14 Andrew Dunkley: Yeah, absolutely. Yeah. Thanks, Barry. Um,
00:16:14 --> 00:16:17 just a side question, Jonti. Do you think
00:16:17 --> 00:16:19 we ever will build such a thing?
00:16:21 --> 00:16:23 Jonti Horner: I'd be a fool to say no on it. I really hope
00:16:23 --> 00:16:26 that we do. And um, given the impact we've
00:16:26 --> 00:16:29 seen both good and bad, from the
00:16:29 --> 00:16:31 advent of reusable spacecraft and the growth
00:16:31 --> 00:16:33 of commercial space, that's dropped the cost
00:16:33 --> 00:16:36 of launching kilogram of material to space by
00:16:36 --> 00:16:38 between a factor of 10 and factor of 100. And
00:16:38 --> 00:16:40 it's been revolutionary. If you could drop
00:16:40 --> 00:16:43 that cost to essentially nothing. What
00:16:43 --> 00:16:46 that enables is an enormous expansion in
00:16:46 --> 00:16:49 our use of space. It also enables the kind of
00:16:49 --> 00:16:51 space tourism type stuff because if you
00:16:52 --> 00:16:54 have a docking station at geostationary
00:16:54 --> 00:16:57 orbit, you've Already done a hell of a lot of
00:16:57 --> 00:16:59 the work of getting out of Earth's gravity.
00:17:00 --> 00:17:02 So it's much easier to launch to Mars or the
00:17:02 --> 00:17:05 moon or pick your tourist destination from
00:17:05 --> 00:17:08 there. Pick your research destination, you
00:17:08 --> 00:17:10 hugely reduce the cost of doing
00:17:10 --> 00:17:13 both. Research, commerce, tourism.
00:17:13 --> 00:17:15 By getting people up to that altitude. You
00:17:15 --> 00:17:17 don't have to get through the atmosphere, but
00:17:17 --> 00:17:19 you also don't have to burn your rocket to
00:17:19 --> 00:17:21 get up, uh, through that hardest, steepest
00:17:21 --> 00:17:24 part of Earth's gravity well. So once it is
00:17:24 --> 00:17:27 technologically feasible, I suspect what
00:17:27 --> 00:17:28 you'll have is it'll become technologically
00:17:28 --> 00:17:31 feasible. Then not too long after that, it
00:17:31 --> 00:17:33 will become commercially feasible. And that's
00:17:33 --> 00:17:35 the point people look at doing it. And, uh,
00:17:35 --> 00:17:37 the big caveat there would be, is it actually
00:17:37 --> 00:17:40 ever going to be technologically feasible?
00:17:40 --> 00:17:42 But it's near enough future science that
00:17:42 --> 00:17:44 people have already had suggestions about the
00:17:44 --> 00:17:47 kind of materials you could use to make
00:17:47 --> 00:17:50 the cable. Because that's a big
00:17:50 --> 00:17:53 constraint is actually making the cable, um,
00:17:53 --> 00:17:55 would need to be a lot stronger than spider
00:17:55 --> 00:17:57 silk, for example. But it is
00:17:58 --> 00:18:01 not so far beyond what we can make now that
00:18:01 --> 00:18:03 people think it's impossible. Rather, people
00:18:03 --> 00:18:05 think it could be feasible, but we don't know
00:18:05 --> 00:18:07 how yet. And in that kind of context, we're
00:18:07 --> 00:18:09 incredibly good at doing the impossible and
00:18:09 --> 00:18:12 the improbable as a species. So, uh, so long
00:18:12 --> 00:18:15 as we don't wipe each other out, so long as
00:18:15 --> 00:18:18 the shutdown eventually ends, then perhaps
00:18:18 --> 00:18:20 we'll be able to figure this out. And, you
00:18:20 --> 00:18:23 know, probably not in our lifetime, but may
00:18:23 --> 00:18:24 well not be as far beyond that as you'd
00:18:24 --> 00:18:25 think.
00:18:25 --> 00:18:27 Andrew Dunkley: Well, uh, if you go back 200 years and tell
00:18:27 --> 00:18:29 people, hey, I, you know, where I come from,
00:18:29 --> 00:18:31 we've been to the moon, they'd think you were
00:18:31 --> 00:18:34 a witch. They just wouldn't believe
00:18:34 --> 00:18:37 it. So, uh, who knows what's possible in 200
00:18:37 --> 00:18:37 years time?
00:18:37 --> 00:18:39 Jonti Horner: Yeah, the thing that makes my head hurt with
00:18:39 --> 00:18:41 that, uh, is we're almost at the point. In
00:18:41 --> 00:18:43 fact, I think we possibly are at the point
00:18:43 --> 00:18:45 now where it is longer since the first
00:18:45 --> 00:18:48 moonwalk than that moonwalk was from the
00:18:48 --> 00:18:49 first powered flight.
00:18:49 --> 00:18:51 Andrew Dunkley: I know. Isn't it amazing?
00:18:52 --> 00:18:54 It's incredible how far we've come in such a
00:18:54 --> 00:18:57 short period of time. M thank you, Barry. Um,
00:18:57 --> 00:18:58 great question.
00:18:58 --> 00:19:00 Uh, our next question coming up in a moment
00:19:00 --> 00:19:02 on Space Nuts.
00:19:06 --> 00:19:09 Space Nuts. And you're with Andrew Dunkley
00:19:09 --> 00:19:11 and John T. Horner. Um, this one comes from
00:19:11 --> 00:19:14 Casey in Colorado. I was hoping that you
00:19:14 --> 00:19:16 could Please explain why TOI
00:19:17 --> 00:19:20 6894B is such a big deal
00:19:20 --> 00:19:23 and what it means for our understanding of
00:19:23 --> 00:19:24 the universe. Love the show, and I hope
00:19:24 --> 00:19:25 you're both well.
00:19:25 --> 00:19:26 Jonti Horner: Thanks.
00:19:26 --> 00:19:28 Andrew Dunkley: Thank you, Casey. Yeah. So I did a bit of
00:19:28 --> 00:19:30 research on this, uh, particular planet,
00:19:30 --> 00:19:33 TOI 6894. It's a massive,
00:19:34 --> 00:19:36 massive gas giant planet. But what makes it
00:19:36 --> 00:19:39 unusual is that its star
00:19:39 --> 00:19:41 is, um, a bit of a mouse.
00:19:42 --> 00:19:45 So they're trying to figure out how such a
00:19:45 --> 00:19:46 massive planet can exist
00:19:47 --> 00:19:50 next to such a tiny star. I think that's the
00:19:50 --> 00:19:51 guts of it, isn't it?
00:19:51 --> 00:19:54 Jonti Horner: It is. And it's a really good example, again,
00:19:54 --> 00:19:57 of the detective story side of
00:19:57 --> 00:20:00 astronomy, the way that we can't really
00:20:00 --> 00:20:01 do experiments, so we have to learn through
00:20:01 --> 00:20:03 observation. And so the interplay is not
00:20:03 --> 00:20:05 experiment and theory like it is in other
00:20:05 --> 00:20:07 disciplines, but it's observation and the.
00:20:07 --> 00:20:09 And, um, that leads to our science being
00:20:09 --> 00:20:11 different in subtle ways, even down to the
00:20:11 --> 00:20:13 structure of how we write and how we
00:20:13 --> 00:20:15 communicate. It's less about testing
00:20:15 --> 00:20:16 hypotheses than other disciplines. You know,
00:20:16 --> 00:20:19 there's a lot of complexity in that. Now,
00:20:19 --> 00:20:21 if you go back to when I was a kid and I was
00:20:22 --> 00:20:23 learning all about astronomy, we didn't know
00:20:23 --> 00:20:26 of any planet from any other star. And we
00:20:26 --> 00:20:27 thought we had a very good feeling of how the
00:20:27 --> 00:20:29 solar system formed and therefore, by
00:20:29 --> 00:20:31 extension, what kind of planets we would
00:20:31 --> 00:20:33 find. Yeah, and we expected that you'd find
00:20:33 --> 00:20:36 giant planets like Jupiter out beyond the
00:20:36 --> 00:20:38 snow line, you know, several astronomical
00:20:38 --> 00:20:39 units from their star, going around on orbits
00:20:39 --> 00:20:41 that are measured in decades, and rocky
00:20:41 --> 00:20:43 planets in the interior. And that's how
00:20:43 --> 00:20:44 planetary systems would form and the solar
00:20:44 --> 00:20:47 system would be typical. We then found
00:20:47 --> 00:20:50 51 Pegasi B, which is a planet comparable to
00:20:50 --> 00:20:52 Jupiter, going around its star every four
00:20:52 --> 00:20:55 days. And that kind of threw everything out.
00:20:55 --> 00:20:57 And we had to improve our theories. Now what
00:20:57 --> 00:21:00 it led to was a refinement of the theories of
00:21:00 --> 00:21:02 planets forming in disks rather than them
00:21:02 --> 00:21:04 being totally chucked out on something new.
00:21:04 --> 00:21:06 But that first discovery of a planet around a
00:21:06 --> 00:21:08 sun like star really set the scene for the
00:21:08 --> 00:21:11 fact that the diversity of planets we find
00:21:11 --> 00:21:14 around other stars is overwhelmingly
00:21:14 --> 00:21:16 greater than we could have ever imagined.
00:21:16 --> 00:21:18 Planets are ubiquitous. Every star has them.
00:21:18 --> 00:21:20 That's what we've learned. But the variety of
00:21:20 --> 00:21:22 planets is much greater than we could have
00:21:22 --> 00:21:25 imagined. And all of that data has been
00:21:25 --> 00:21:27 a fabulous resource for scientists trying to
00:21:27 --> 00:21:29 understand the process of planet formation
00:21:29 --> 00:21:32 and the variety of ways that that process can
00:21:32 --> 00:21:35 proceed effectively. Every planetary system
00:21:35 --> 00:21:37 will be unique in the same way every human's
00:21:37 --> 00:21:39 unique. You know, they're the product of the
00:21:39 --> 00:21:41 environment that they form in. The mass of
00:21:41 --> 00:21:43 the disk is important, the mass of the star,
00:21:43 --> 00:21:44 but also the cluster environment they form
00:21:44 --> 00:21:47 in. There's a lot of things going on that
00:21:47 --> 00:21:49 mean if you have two identical stars with two
00:21:49 --> 00:21:51 identical disks, you'll still get different
00:21:51 --> 00:21:53 planetary systems at the end. So we're
00:21:53 --> 00:21:55 learning more about planet formation. And
00:21:55 --> 00:21:58 it's the outliers and the oddities that
00:21:58 --> 00:21:59 really drive that science forward.
00:22:00 --> 00:22:03 Which brings us to TOI 6894. What we
00:22:03 --> 00:22:05 found typically is that, uh, giant planets
00:22:05 --> 00:22:08 are common in the cosmos. We find them easier
00:22:08 --> 00:22:09 than everything else because they're more
00:22:09 --> 00:22:12 obvious. So our discovery techniques are
00:22:12 --> 00:22:14 biased towards finding planets the size of
00:22:14 --> 00:22:16 Jupiter and Saturn and against finding
00:22:16 --> 00:22:18 planets the size of the Earth. That's why we
00:22:18 --> 00:22:20 find a lot more of them. And, um, what the
00:22:20 --> 00:22:22 results have shown is that, uh, giant
00:22:22 --> 00:22:24 planets, massive planets like Jupiter and
00:22:24 --> 00:22:27 Saturn, are, um, more common the more massive
00:22:27 --> 00:22:30 the star is. They're also more common the
00:22:30 --> 00:22:32 higher the metallicity of the star is. So the
00:22:32 --> 00:22:33 higher the amount of solid material would
00:22:33 --> 00:22:36 have been around that star. And typically
00:22:36 --> 00:22:39 we don't find giant planets like Jupiter
00:22:39 --> 00:22:42 and Saturn around the lowest mass stars.
00:22:42 --> 00:22:44 And the argument has always been that low
00:22:44 --> 00:22:46 mass stars form from low mass disks where
00:22:46 --> 00:22:48 there's just not simply enough for planets to
00:22:48 --> 00:22:51 form there. Then you get
00:22:51 --> 00:22:54 TOI 6894B. So the
00:22:54 --> 00:22:57 star TOI 6894 is a little red dwarf.
00:22:57 --> 00:22:59 It's only about 20% the mass of the sun,
00:22:59 --> 00:23:02 about 238 light years away. The
00:23:02 --> 00:23:05 planet going round it is a little bit bigger
00:23:05 --> 00:23:07 than Saturn, but about half the mass of our
00:23:07 --> 00:23:09 giant planet. So it's another one of these
00:23:09 --> 00:23:11 superpuff planets that we've talked about
00:23:11 --> 00:23:13 before. It's heavily irradiated, has been
00:23:13 --> 00:23:15 inflated, and that probably suggests that
00:23:15 --> 00:23:18 it's migrated in in the recent past. Now
00:23:18 --> 00:23:20 people who've looked at data from Kepler
00:23:21 --> 00:23:23 and TESS more recently, which looked at so
00:23:23 --> 00:23:25 many stars, have been able to do a kind of
00:23:25 --> 00:23:28 statistical study. And what they've found is,
00:23:28 --> 00:23:30 uh, for red dwarfs like TOI,
00:23:31 --> 00:23:33 um, 6894, only about
00:23:33 --> 00:23:36 1.5% of all red dwarfs harbor any giant
00:23:36 --> 00:23:38 planets. And TOI
00:23:38 --> 00:23:41 6894 is the least massive star to be found
00:23:41 --> 00:23:44 with an orbiting giant planet around it. So
00:23:44 --> 00:23:46 that's why it's really, really interesting.
00:23:46 --> 00:23:48 Now there's a number of different processes
00:23:48 --> 00:23:51 that go on in planet formation and, um, star
00:23:51 --> 00:23:53 formation. And we've talked before about the
00:23:53 --> 00:23:56 Blurred lines between planets and
00:23:56 --> 00:23:58 brown dwarfs and stars. And back in the day,
00:23:58 --> 00:24:00 we thought we had a very clear rational
00:24:00 --> 00:24:01 explanation that they're formed in different
00:24:01 --> 00:24:04 ways. But now we see brown
00:24:04 --> 00:24:06 dwarfs being discovered free floating that
00:24:06 --> 00:24:09 are lower mass than the canonical traditional
00:24:09 --> 00:24:11 13 Jupiter mass limit. Anything smaller than
00:24:11 --> 00:24:13 13 Jupiter mass used to be thought of as a
00:24:13 --> 00:24:15 planet. Similarly, we're finding things that
00:24:15 --> 00:24:16 they're calling planets that are more than 13
00:24:16 --> 00:24:18 Jupiter masses. So the lines are getting
00:24:18 --> 00:24:18 blurred.
00:24:19 --> 00:24:19 Andrew Dunkley: Yeah.
00:24:19 --> 00:24:22 Jonti Horner: And I think we may see a bit of a
00:24:22 --> 00:24:24 paradigm shift in years and decades to come,
00:24:25 --> 00:24:27 where part of what defines whether you're a
00:24:27 --> 00:24:29 planet or a brown dwarf at the top end is
00:24:29 --> 00:24:31 actually how you formed and by extension,
00:24:31 --> 00:24:34 what's buried deep in your core. So a
00:24:34 --> 00:24:36 planet like Jupiter has a massive,
00:24:37 --> 00:24:40 you know, 20, 30 earth mass, solid core at
00:24:40 --> 00:24:41 the middle because it formed from a process
00:24:41 --> 00:24:44 of core accretion. You get solid material
00:24:44 --> 00:24:46 agglomerating, forming bigger and bigger
00:24:46 --> 00:24:47 bits, until you form things kilometers
00:24:47 --> 00:24:50 across, then thousands of kilometers across
00:24:50 --> 00:24:52 objects like the Earth. And the more they
00:24:52 --> 00:24:54 eat, the bigger they get. Eventually you get
00:24:54 --> 00:24:56 to 20 or 30 times the mass of the earth,
00:24:56 --> 00:24:58 well, 10 or 12 times the mass of the Earth to
00:24:58 --> 00:25:00 start the process. When you're at that point,
00:25:00 --> 00:25:02 your gravity is strong enough to start
00:25:02 --> 00:25:04 capturing hydrogen and helium gas from the
00:25:04 --> 00:25:06 nebula that previously would have escaped,
00:25:06 --> 00:25:08 you finally can hold onto, um, it. And, um,
00:25:08 --> 00:25:10 because there's more of hydrogen and helium
00:25:10 --> 00:25:12 than everything else combined by a couple of
00:25:12 --> 00:25:15 orders of magnitude, 98% of everything is
00:25:15 --> 00:25:17 hydrogen or helium. Suddenly you've got this
00:25:17 --> 00:25:19 enormous new untapped food source. You can
00:25:19 --> 00:25:21 quickly devour all there is, and your mass
00:25:21 --> 00:25:23 grows really rapidly until you open a gap in
00:25:23 --> 00:25:25 the disk, and voila, you've got a giant
00:25:25 --> 00:25:27 planet in a gap. And we talked about this a
00:25:27 --> 00:25:30 bit last week. That's core accretion.
00:25:30 --> 00:25:32 That leads to giant planets that are planets
00:25:32 --> 00:25:34 with a solid core and a thick atmosphere. And
00:25:34 --> 00:25:36 that atmosphere can be the bulk of their
00:25:36 --> 00:25:38 mass. You've then got a
00:25:38 --> 00:25:40 method called gravitational instability,
00:25:40 --> 00:25:42 where your disk is sufficiently massive
00:25:42 --> 00:25:44 compared to the star in the middle, that it
00:25:44 --> 00:25:47 can become unstable itself. And you can get
00:25:47 --> 00:25:49 it essentially globbing together to form
00:25:49 --> 00:25:51 massive objects on a very short time scale.
00:25:51 --> 00:25:53 And that's probably, to be honest, the
00:25:53 --> 00:25:56 process by which binary stars form, where you
00:25:56 --> 00:25:58 get a second star forming on a quite wide,
00:25:58 --> 00:26:00 elongated orbit, whatever. And I've always
00:26:00 --> 00:26:03 had a suspicion back from when earlier in my
00:26:03 --> 00:26:05 career I was at the University of Bern, and
00:26:05 --> 00:26:07 this is 20 years ago now, there was this kind
00:26:07 --> 00:26:09 of conflict for giant Planets where people
00:26:09 --> 00:26:12 said one of these two methods will be right
00:26:12 --> 00:26:13 and the other one will be wrong. And you've
00:26:13 --> 00:26:15 got core accretion or, uh, gravitational
00:26:15 --> 00:26:16 instability. And it was a big kind of which
00:26:16 --> 00:26:18 one of them is right. And I've always had the
00:26:18 --> 00:26:20 feeling that in the right conditions both of
00:26:20 --> 00:26:23 them can happen. And this suspicion that
00:26:23 --> 00:26:26 brown dwarfs and stellar companions
00:26:26 --> 00:26:28 probably form through this gravitational
00:26:28 --> 00:26:31 instability process, which leads to more
00:26:31 --> 00:26:32 instability and kind of lowers the likelihood
00:26:32 --> 00:26:34 of planets then forming in the system. And
00:26:34 --> 00:26:36 you'd form an object there, ah, that doesn't
00:26:36 --> 00:26:38 have that massive core in the center. It's
00:26:38 --> 00:26:41 basically the composition will match the
00:26:41 --> 00:26:43 composition of the material in the universe.
00:26:44 --> 00:26:46 This is a really interesting one because this
00:26:46 --> 00:26:48 planet is so much so massive compared to
00:26:48 --> 00:26:51 its star. This is kind of equivalent to the
00:26:51 --> 00:26:54 sun having a 5 or 10 Jupiter mass planet,
00:26:54 --> 00:26:56 probably something like that, because m more
00:26:56 --> 00:26:57 massive star would have more mass and you
00:26:57 --> 00:26:59 wouldn't just five times the mass of the star
00:26:59 --> 00:27:01 is five times the mass of the planet. It will
00:27:01 --> 00:27:03 go a bit more than that. So it's a real
00:27:03 --> 00:27:06 surprise and there's a lot of investigation
00:27:06 --> 00:27:07 to be done to try and figure out what the
00:27:07 --> 00:27:10 formation process of this object is. The fact
00:27:10 --> 00:27:13 it's a super puff, it's puffed up, it's
00:27:13 --> 00:27:14 bigger than Saturn, but less massive than
00:27:14 --> 00:27:17 Saturn, suggests that, um, either
00:27:17 --> 00:27:19 it's very close into the star and it's
00:27:19 --> 00:27:22 getting hugely irradiated. If that's the
00:27:22 --> 00:27:23 case and it's been losing mass, it was
00:27:23 --> 00:27:26 probably more massive in the past. Um, which
00:27:26 --> 00:27:28 adds further weight to maybe this was a
00:27:28 --> 00:27:30 bigger thing in the past and maybe it could
00:27:30 --> 00:27:32 have been a very low mass brown dwarf rather
00:27:32 --> 00:27:34 than a very high mass planet. Or maybe it's
00:27:34 --> 00:27:37 telling us that you can get M dwarfs, red
00:27:37 --> 00:27:39 dwarfs, which have a disk massive enough to
00:27:39 --> 00:27:41 form giant planets on occasion in the right
00:27:41 --> 00:27:44 setup, and we just need to learn more.
00:27:45 --> 00:27:47 Um, but it seems very unlikely
00:27:48 --> 00:27:51 that if the properties of the disk
00:27:51 --> 00:27:53 around this star, uh, were similar to the
00:27:53 --> 00:27:55 bulk of disk we found, there should not have
00:27:55 --> 00:27:58 been enough solid material to get the core
00:27:58 --> 00:28:00 accretion process to go quickly enough for
00:28:00 --> 00:28:02 you to get a giant planet, never mind one
00:28:02 --> 00:28:04 close enough in like this one, to then become
00:28:04 --> 00:28:07 a bit of a superpuff. So there's a lot to
00:28:07 --> 00:28:08 learn. It's very close to its star. It's only
00:28:09 --> 00:28:12 3.9 million kilometers out from the
00:28:12 --> 00:28:14 star. So it's much more
00:28:14 --> 00:28:17 comparable to the Jovian moons. If you
00:28:17 --> 00:28:19 imagine the star being where Jupiter is, this
00:28:19 --> 00:28:20 is comparable to some of the moons of Jupiter
00:28:20 --> 00:28:23 and distance. And that's another of the
00:28:23 --> 00:28:24 reasons it's just really hard to imagine how
00:28:24 --> 00:28:26 it could been have form so close in.
00:28:27 --> 00:28:29 There's a lot to dig into in this. They're
00:28:29 --> 00:28:30 looking at the chemistry of the atmosphere
00:28:30 --> 00:28:32 because this planet's close enough in to be
00:28:32 --> 00:28:34 hot enough that we can actually get light
00:28:34 --> 00:28:36 from it and we can look at its atmosphere
00:28:36 --> 00:28:38 seems to be kind of methane dominated, I
00:28:38 --> 00:28:40 think, which is really, really odd. Um,
00:28:40 --> 00:28:42 there's all sorts of weird stuff going on.
00:28:43 --> 00:28:46 Um, but because red dwarf
00:28:46 --> 00:28:47 stars are so common, even though giant
00:28:47 --> 00:28:50 planets like this are rare per red dwarf,
00:28:50 --> 00:28:52 there's probably a hell of a lot of them out
00:28:52 --> 00:28:53 there. You know, red dwarfs are the most
00:28:53 --> 00:28:56 common star in the galaxy by far. You know,
00:28:56 --> 00:28:58 some estimates are, you know, up to three
00:28:58 --> 00:29:01 quarters of all gas in our size in our galaxy
00:29:01 --> 00:29:02 will count as red dwarfs. Which means he
00:29:02 --> 00:29:05 could have 100, 200,
00:29:05 --> 00:29:08 300 billion of them out there. So even if
00:29:08 --> 00:29:11 only 1% of those stars have a giant planet
00:29:11 --> 00:29:13 like this, you know, 1% of,
00:29:14 --> 00:29:16 you know, 100 billion stars is still a
00:29:16 --> 00:29:17 billion stars.
00:29:17 --> 00:29:18 Jonti Horner: Yes.
00:29:18 --> 00:29:20 Jonti Horner: Now maybe this planet is both rare and common
00:29:20 --> 00:29:21 at the same time.
00:29:21 --> 00:29:24 Andrew Dunkley: Yeah, that sounds like a very good
00:29:24 --> 00:29:27 theory actually. Um, Casey, thanks
00:29:27 --> 00:29:29 for the question. If you'd like to read up on
00:29:29 --> 00:29:32 it, uh, you can go to uh, Psy News,
00:29:32 --> 00:29:34 the website, because they've got a great
00:29:34 --> 00:29:35 article on it, uh, but they've also published
00:29:35 --> 00:29:38 a recent paper, uh, in the
00:29:38 --> 00:29:40 journal Nature Astronomy.
00:29:43 --> 00:29:45 Jonti Horner: 3, 2, 1.
00:29:46 --> 00:29:46 Space.
00:29:48 --> 00:29:49 Andrew Dunkley: Our uh, final question.
00:29:50 --> 00:29:52 Jonti. Uh, I don't know how to introduce
00:29:52 --> 00:29:55 this, so I'm just going to let it speak for
00:29:55 --> 00:29:55 itself.
00:29:55 --> 00:29:57 Jonti Horner: Hello, space nuts.
00:29:57 --> 00:29:59 Andrew Dunkley: This is Philip McCrackpipe, future Nobel
00:29:59 --> 00:30:02 Prize winner, here again. This time I've got
00:30:02 --> 00:30:03 my bony lassie.
00:30:03 --> 00:30:06 Jonti Horner: The famous English soprano. I need a fix here
00:30:06 --> 00:30:06 with me.
00:30:07 --> 00:30:10 Jonti Horner: That's a neater fix. F I C K S.
00:30:10 --> 00:30:13 Thank you. Not if F I X.
00:30:13 --> 00:30:16 So many people get that wrong. I have this
00:30:16 --> 00:30:19 question about Gale Crater on Mars and what
00:30:19 --> 00:30:21 kind of life it might have supported. Being
00:30:21 --> 00:30:24 a famous soprano, I'd like uh, to sing it
00:30:24 --> 00:30:27 to you. Pardon my voice today
00:30:27 --> 00:30:30 I have a slight touch of the anthrax.
00:30:32 --> 00:30:35 How many lovely life old might have grown
00:30:35 --> 00:30:37 in an ancient Martian crater?
00:30:38 --> 00:30:41 Could they have thrived or only just survived
00:30:41 --> 00:30:43 in an ancient Martian?
00:30:45 --> 00:30:47 Were they all just single soul? Did they fly
00:30:47 --> 00:30:49 like Tinkerbell and laugh and sing and play
00:30:50 --> 00:30:52 a microscopic trees?
00:30:53 --> 00:30:56 How, um, many lovely life forms made grown in
00:30:56 --> 00:30:59 an ancient Martian crater?
00:30:59 --> 00:30:59 Jonti Horner: Ah.
00:30:59 --> 00:31:02 Jonti Horner: Did they breathe the atmosphere where the
00:31:02 --> 00:31:04 predators, the fear elucidate your views,
00:31:04 --> 00:31:08 ecosystem.
00:31:10 --> 00:31:12 Thank lovely space nuts for listening to this
00:31:12 --> 00:31:15 tripe about an ancient Martian
00:31:15 --> 00:31:16 creator.
00:31:22 --> 00:31:25 Andrew Dunkley: Uh, um, I hope you get over the antlex real
00:31:25 --> 00:31:28 soon. Thanks, Anita. Um, I
00:31:28 --> 00:31:29 think I need a very.
00:31:29 --> 00:31:31 Jonti Horner: Different kind of musical ensemble. If I
00:31:31 --> 00:31:32 remember rightly.
00:31:32 --> 00:31:34 Andrew Dunkley: Yes, I think I need a fix.
00:31:34 --> 00:31:34 Jonti Horner: Uh.
00:31:36 --> 00:31:39 Andrew Dunkley: Bottom line, was there, or
00:31:39 --> 00:31:42 could there still be life in Gale Crater and
00:31:42 --> 00:31:42 what would it be like?
00:31:43 --> 00:31:46 Jonti Horner: Lots of places to go with this. I mean, two
00:31:46 --> 00:31:48 immediate diversions just spring to mind
00:31:48 --> 00:31:49 listening to that. It's lovely to get a
00:31:49 --> 00:31:51 musical entry from such a storied soprano,
00:31:51 --> 00:31:54 but reminds me, probably my favorite group,
00:31:55 --> 00:31:57 Finnish symphonic metal group called
00:31:57 --> 00:32:00 Nightwish. And this is relevant, I promise.
00:32:00 --> 00:32:03 Um, symphonic metal is this weird fusion of
00:32:03 --> 00:32:05 metal and opera, so you could describe it as
00:32:05 --> 00:32:08 operatic met. And the lead singer is a very
00:32:08 --> 00:32:11 storied classical soprano called Flo
00:32:11 --> 00:32:13 Jansen, who's just ridiculously awesome in
00:32:13 --> 00:32:16 many, many ways. Um, reason it's relevant is
00:32:16 --> 00:32:17 we were talking earlier on about Eugene
00:32:17 --> 00:32:20 Shoemaker, um, in the previous episode about
00:32:20 --> 00:32:22 Asher's going to the moon, things like this.
00:32:23 --> 00:32:26 Um, Nightwish, on their most recent
00:32:26 --> 00:32:29 no album before last had a track called
00:32:29 --> 00:32:31 Shoemaker, which was a eulogy, a tribute to
00:32:31 --> 00:32:34 Eugene Shoemaker, which has a lot of rocky
00:32:34 --> 00:32:36 stuff at the start, but from about 3 minutes
00:32:36 --> 00:32:38 50 onwards has a very, very operatic,
00:32:39 --> 00:32:41 classical, um, Latin funeral mass,
00:32:42 --> 00:32:44 um, which is utterly astonishing. So I do
00:32:44 --> 00:32:46 recommend people. I don't know if we can play
00:32:46 --> 00:32:47 it on the podcast. I don't know if we can
00:32:47 --> 00:32:49 play out because I don't know how rights
00:32:49 --> 00:32:50 issues work.
00:32:50 --> 00:32:53 Andrew Dunkley: Um, but, yeah, there are rights issues
00:32:53 --> 00:32:56 which precludes us, I'm afraid. I did
00:32:56 --> 00:32:58 listen to what you sent me. You sent me a
00:32:58 --> 00:33:00 link, uh, on YouTube Music, so we could
00:33:00 --> 00:33:02 probably send people there.
00:33:02 --> 00:33:04 Jonti Horner: But, yeah, it's a bit of a musical tour de
00:33:04 --> 00:33:06 force because it's got bits from William
00:33:06 --> 00:33:09 Shakespeare in there, which is the epitaph on
00:33:09 --> 00:33:11 Schumacher's tomb. That's why you've got the
00:33:11 --> 00:33:13 bit of Shakespeare's book and what in that.
00:33:13 --> 00:33:15 It's unusual, but it's incredibly touching
00:33:16 --> 00:33:18 anyway, so. Love a bit of musical science.
00:33:18 --> 00:33:20 The other thing that occurs without casting
00:33:20 --> 00:33:23 any aspersions on Anita there is the ability
00:33:23 --> 00:33:25 to sing while saying in character, which is
00:33:25 --> 00:33:28 good. And it reminds me of another thing I
00:33:28 --> 00:33:30 listened to, and I've listened to multiple
00:33:30 --> 00:33:32 times now, the phenomenon that is Dungeon
00:33:32 --> 00:33:35 Crawler Carl. Um, and at the end of the
00:33:35 --> 00:33:38 first audiobook, I was a bit put
00:33:38 --> 00:33:40 aback because there wasn't a cast list. And I
00:33:40 --> 00:33:43 thought, hang on, this is a bit Dodged.
00:33:43 --> 00:33:45 There's multiple people involved with this
00:33:45 --> 00:33:46 who are not getting credit. There's just this
00:33:46 --> 00:33:48 one guy getting credit for doing all the
00:33:48 --> 00:33:49 voice work and all the rest of it. And it
00:33:49 --> 00:33:52 really is just one guy. And it's
00:33:52 --> 00:33:54 remarkable how certain
00:33:54 --> 00:33:57 performers can voice multiple different
00:33:57 --> 00:33:59 characters to a degree of distinction that
00:34:00 --> 00:34:02 um, you assume that there's multiple people
00:34:02 --> 00:34:04 involved in the voicing. So, you know,
00:34:04 --> 00:34:07 incredible ability to sing well in character
00:34:07 --> 00:34:09 and stuff like that. So huge uh, credit on
00:34:09 --> 00:34:12 that in terms of the question and
00:34:12 --> 00:34:13 questions.
00:34:13 --> 00:34:15 It's all about life on Mars. Now we know that
00:34:15 --> 00:34:18 Mars in its youth was both
00:34:18 --> 00:34:21 warm and wet. It was an ocean planet that's
00:34:21 --> 00:34:23 fairly well established. Uh, and the
00:34:23 --> 00:34:25 transition from warm, wet Mars to cool, dry
00:34:25 --> 00:34:27 Mars would have been very slow and gradual.
00:34:27 --> 00:34:30 So any life that did get going will have had
00:34:30 --> 00:34:32 time to adapt and move potentially. That's a
00:34:32 --> 00:34:34 big part of the focus of the search for life
00:34:34 --> 00:34:37 on Mars. Both looking for evidence of past
00:34:37 --> 00:34:39 life and um, that's part of what the rovers
00:34:39 --> 00:34:41 are doing, driving around in gray in Gale and
00:34:41 --> 00:34:44 Jezero Crater, or Jezero Crater I think it's
00:34:44 --> 00:34:46 pronounced. It's also why we're interested,
00:34:46 --> 00:34:48 for example in the lakes of permanent liquid
00:34:48 --> 00:34:51 water at Mars south pole. But we
00:34:51 --> 00:34:52 don't know for a fact that there was life on
00:34:52 --> 00:34:55 Mars. It still was there, wasn't there? We're
00:34:55 --> 00:34:58 trying to find out. The idea though is that
00:34:58 --> 00:35:01 when Mars was young it was warm and wet, it
00:35:01 --> 00:35:03 had oceans. There may have been icy, slushy
00:35:03 --> 00:35:05 oceans, more like what you get in the Arctic
00:35:05 --> 00:35:07 than what you get near the equator. We don't
00:35:07 --> 00:35:09 fully know on that yet. But there was a
00:35:09 --> 00:35:12 vast expanse of liquid water on Mars surface
00:35:12 --> 00:35:14 for an incredibly long protracted period.
00:35:15 --> 00:35:17 All the conditions that on Earth would lead
00:35:17 --> 00:35:20 to life establishing and thriving. So
00:35:20 --> 00:35:22 there's a very real possibility that Gale
00:35:22 --> 00:35:25 Krata, this ancient Martian creator, was
00:35:25 --> 00:35:28 teeming with life in the past. It is,
00:35:28 --> 00:35:31 I think. So the challenge here is that
00:35:31 --> 00:35:33 we've only got one example of life in the
00:35:33 --> 00:35:35 universe to go off, which is life on the
00:35:35 --> 00:35:37 Earth. So we tend to form all our
00:35:37 --> 00:35:39 assumptions about the pathway that life will
00:35:39 --> 00:35:41 follow and how it will develop based on that
00:35:41 --> 00:35:44 example. Now just with the last question, we
00:35:44 --> 00:35:47 were talking about our ideas on the formation
00:35:47 --> 00:35:49 of planets when we only had one planetary
00:35:49 --> 00:35:51 system to go on and how wrong they were when
00:35:51 --> 00:35:53 we found the second planetary system around a
00:35:53 --> 00:35:56 sun like star. So the caveat to everything
00:35:56 --> 00:35:58 I'm about to say is that currently we know of
00:35:58 --> 00:36:00 one place with life and one planet with life.
00:36:00 --> 00:36:03 So I'm basing it off assumptions based on how
00:36:03 --> 00:36:06 things developed on Earth. And on Earth, we
00:36:06 --> 00:36:08 had simple life from about three and a
00:36:08 --> 00:36:11 half thousand million years ago. The evidence
00:36:11 --> 00:36:13 of, so the oldest fossils on Earth that are
00:36:13 --> 00:36:16 widely accepted, it's about 3.5 billion years
00:36:16 --> 00:36:18 ago, found in the Pilbara region in Western
00:36:18 --> 00:36:20 Australia. There are some fossils that are
00:36:20 --> 00:36:21 arguably older, but they're still
00:36:21 --> 00:36:24 controversial. For
00:36:24 --> 00:36:27 the first 3 billion years of life on Earth,
00:36:27 --> 00:36:29 all you had was single celled life. You had
00:36:29 --> 00:36:31 an incredible diversity and variety of simple
00:36:31 --> 00:36:34 life, but that's all you had. So only about
00:36:34 --> 00:36:36 500 million years ago, give or take, that,
00:36:36 --> 00:36:39 you start to get complex life. So the
00:36:39 --> 00:36:41 argument following that would be if
00:36:41 --> 00:36:44 Mars had life and, um, if that
00:36:44 --> 00:36:46 life followed a similar pathway to the Earth,
00:36:47 --> 00:36:49 then you would expect that that ancient life
00:36:49 --> 00:36:51 would all have been simple life. Now, the
00:36:51 --> 00:36:52 other thing that argues for that is if you
00:36:52 --> 00:36:54 look around on the Earth today, we've got
00:36:54 --> 00:36:56 life in abundance all over the place. But the
00:36:56 --> 00:36:58 more complex the life is, the more limited
00:36:58 --> 00:37:00 the variety of environments that it can exist
00:37:00 --> 00:37:02 in, if that makes sense.
00:37:02 --> 00:37:03 Andrew Dunkley: Yeah.
00:37:03 --> 00:37:06 Jonti Horner: So obviously simple life can exist in a
00:37:06 --> 00:37:09 wider variety of conditions and, um, will
00:37:09 --> 00:37:12 exist earlier than complex life. And
00:37:12 --> 00:37:15 so the argument then would be with all those
00:37:15 --> 00:37:16 assumptions, and I know I'm doing a lot of
00:37:16 --> 00:37:18 COVID your own ass here, but with the
00:37:18 --> 00:37:20 assumption that everything followed the way
00:37:20 --> 00:37:22 that things went on Earth, my expectation
00:37:22 --> 00:37:24 would have been that Gale Crater could well
00:37:24 --> 00:37:26 have been teeming with life, but it would
00:37:26 --> 00:37:27 have been simple life. It would have been
00:37:27 --> 00:37:29 single celled life. Now, single celled life
00:37:29 --> 00:37:32 still lives, a very vibrant and
00:37:32 --> 00:37:34 diverse set of lives. So there will be things
00:37:34 --> 00:37:36 interfering with each other and eating each
00:37:36 --> 00:37:38 other and all that kind of happy stuff going
00:37:38 --> 00:37:41 on. But it's likely that there
00:37:41 --> 00:37:44 weren't giant sharks or octo sharks
00:37:44 --> 00:37:46 or whatever you know, swimming around in the
00:37:46 --> 00:37:49 ocean in Gale Crater. And I suspect that if
00:37:49 --> 00:37:51 there had have been, we'd already possibly be
00:37:51 --> 00:37:53 finding evidence in the form of fossils. I
00:37:53 --> 00:37:56 may be wrong on that, but I suspect that the
00:37:56 --> 00:37:58 fact we haven't yet got definitive proof of
00:37:58 --> 00:38:01 ancient life on Mars suggests that the life
00:38:01 --> 00:38:03 that was there, if it was there, uh, was
00:38:03 --> 00:38:05 simple life and single celled life rather
00:38:05 --> 00:38:08 than complex stuff. But I stand to be
00:38:08 --> 00:38:09 corrected on that. I look forward to the
00:38:09 --> 00:38:12 confirmation of the discovery of ancient
00:38:12 --> 00:38:14 fossils on Mars, if we ever get there.
00:38:14 --> 00:38:15 Confirmation of life elsewhere will be
00:38:15 --> 00:38:18 awesome. So it might be worth getting Anita
00:38:18 --> 00:38:21 back on the show, uh, in a decade or so
00:38:21 --> 00:38:23 to sing the sequel is now that we know there
00:38:23 --> 00:38:25 Was life there? What was it like? Yeah, yeah.
00:38:25 --> 00:38:28 Andrew Dunkley: Um, but I think we will
00:38:28 --> 00:38:31 find something somewhere. Probably Mars,
00:38:31 --> 00:38:33 but maybe on some of the ice moons
00:38:34 --> 00:38:37 further out. But there's got to be
00:38:37 --> 00:38:39 something. Uh, I think it'll be microbial, as
00:38:39 --> 00:38:42 you said. But it's just,
00:38:43 --> 00:38:45 you look how life just grabs on
00:38:46 --> 00:38:49 on Earth given
00:38:49 --> 00:38:51 minimal opportunity. And
00:38:51 --> 00:38:53 I think that that same
00:38:55 --> 00:38:57 thing exists in the universe
00:38:57 --> 00:39:00 elsewhere. Um, life, if there is
00:39:00 --> 00:39:03 just a small opportunity, it will grow
00:39:03 --> 00:39:06 and I think that's what we will find. But,
00:39:06 --> 00:39:09 uh, whether or not we find another
00:39:10 --> 00:39:12 so called intelligent
00:39:13 --> 00:39:16 place in the universe or an intelligent
00:39:16 --> 00:39:19 species, that's a bigger call
00:39:19 --> 00:39:21 and a completely different ball game indeed.
00:39:21 --> 00:39:23 Uh, thank you for the question, Anita. And if
00:39:23 --> 00:39:25 you would like to listen to the music that
00:39:25 --> 00:39:27 Jonti, uh, was referring to, you can go to
00:39:27 --> 00:39:30 YouTube Music, do a search for Nightwish,
00:39:30 --> 00:39:32 Shoemaker, uh, the official lyric video.
00:39:33 --> 00:39:35 Um, they've got 1.82 million
00:39:35 --> 00:39:38 subscribers. Yeah, it's extraordinary.
00:39:38 --> 00:39:41 Jonti Horner: It's a style of music that isn't really
00:39:41 --> 00:39:43 widely known in Australia. So when I've gone
00:39:43 --> 00:39:44 to see them on the odd occasion, they've come
00:39:44 --> 00:39:46 over here. We've been down at the Tivoli in
00:39:46 --> 00:39:48 Brisbane, which is kind of a thousand people.
00:39:49 --> 00:39:50 When they go anywhere else in the world,
00:39:50 --> 00:39:52 they're doing packed stadiums with a hundred
00:39:52 --> 00:39:55 thousand plus. So it's a different genre.
00:39:55 --> 00:39:58 Um, they, along with a group called Epica and
00:39:58 --> 00:40:00 a male group called Camelot, are probably the
00:40:00 --> 00:40:02 three leading light groups in that genre of
00:40:02 --> 00:40:05 symphonic metal, which is the interface of
00:40:05 --> 00:40:07 opera and rock effectively. Um,
00:40:07 --> 00:40:10 but they've had a number of scientifically
00:40:10 --> 00:40:12 themed songs over the years. In fact, there's
00:40:12 --> 00:40:14 one that I have as recommended reading stroke
00:40:14 --> 00:40:16 listening for my undergrad students. That's
00:40:16 --> 00:40:19 kind of of a 20 odd minute long story of the
00:40:19 --> 00:40:21 evolution of the planetary system and life on
00:40:21 --> 00:40:23 Earth and all the rest of it. So they've done
00:40:23 --> 00:40:23 interesting things.
00:40:24 --> 00:40:25 Andrew Dunkley: I'm sure they have.
00:40:25 --> 00:40:26 Jonti Horner: All right. Shoemakers are good. Listen.
00:40:27 --> 00:40:29 Andrew Dunkley: Excellent. All right, uh, thanks to everyone
00:40:29 --> 00:40:32 who contributed. If you would like to send a
00:40:32 --> 00:40:34 question into, um, the Space
00:40:35 --> 00:40:36 Nuts website, just go to
00:40:36 --> 00:40:39 spacenutspodcast.com or spacenuts
00:40:39 --> 00:40:42 IO and click on the AMA
00:40:42 --> 00:40:44 button at the top and send us your, uh, text
00:40:44 --> 00:40:47 or audio question. Don't forget to tell us,
00:40:47 --> 00:40:48 tell us who you are and where you're from,
00:40:49 --> 00:40:51 uh, and leave your email address so we can
00:40:51 --> 00:40:52 spam the hell out of you. No, I'm only
00:40:52 --> 00:40:55 kidding. Although I think that is part of the
00:40:55 --> 00:40:58 deal. M. We'll see. But, um,
00:40:58 --> 00:41:00 yes. And, uh, uh, Guess what? Huw in the
00:41:00 --> 00:41:03 studio just turned up. Hi, Huw. Bye,
00:41:03 --> 00:41:06 Huw. And thanks to you,
00:41:06 --> 00:41:08 Jonti. We'll catch you on the next episode.
00:41:08 --> 00:41:09 Jonti Horner: It's a pleasure. Looking forward to it.
00:41:10 --> 00:41:12 Andrew Dunkley: Uh, Johnny Horner, professor of astrophysics,
00:41:12 --> 00:41:15 uh, at the University of Southern Queensland.
00:41:15 --> 00:41:17 And we thank him. We thank everybody and
00:41:18 --> 00:41:20 thank you. Uh, uh, and from me, Andrew
00:41:20 --> 00:41:23 Dunkley, thank you for your company. We'll
00:41:23 --> 00:41:24 catch you on the very next episode of Space
00:41:24 --> 00:41:25 Nuts.
00:41:25 --> 00:41:26 Jonti Horner: Bye. Bye.
00:41:27 --> 00:41:29 You'll be listening to the Space Nuts
00:41:29 --> 00:41:32 podcast, available at
00:41:32 --> 00:41:34 Apple Podcasts, Spotify,
00:41:34 --> 00:41:37 iHeartRadio, or your favorite podcast
00:41:37 --> 00:41:39 player. You can also stream
00:41:39 --> 00:41:41 ondemand@bytes.com.
00:41:41 --> 00:41:43 Andrew Dunkley: This has been another quality podcast
00:41:43 --> 00:41:45 production from bytes.
00:41:45 --> 00:41:45 Jonti Horner: Com.
00:41:45 --> 00:41:45 Jonti Horner: Um.