Cosmic Q&A: From Redshift to the Moon's Hidden Temperatures
Space Nuts: Astronomy Insights & Cosmic DiscoveriesSeptember 07, 2026
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00:30:0627.62 MB

Cosmic Q&A: From Redshift to the Moon's Hidden Temperatures

Space Nuts: Q&A on the Swift Satellite, Redshift, and Hypothetical White Holes
In this engaging Q&A edition of Space Nuts, hosts Andrew Dunkley and Professor Fred Watson dive into a myriad of intriguing questions posed by listeners. From the fate of the Swift satellite to the mysteries of redshift and the speculative nature of white holes, this episode covers a wide range of cosmic curiosities.
Key topics include:
- The fate of the Swift satellite and the challenges faced by the Link mission meant to boost its orbit.
- An exploration of redshift and the implications of energy loss in distant light.
- Insights into the temperature variations on the Moon and the potential for human habitation beneath its surface.
- A thought-provoking discussion on the hypothetical merger of black holes and white holes, and what that could mean for our understanding of the universe.
Join Andrew and Fred Watson as they tackle these questions with their signature blend of humour and expertise, providing listeners with a deeper understanding of the cosmos.
00:00 - This is where the audience asks us questions, we scratch our heads
01:20 - Do you always record on the same day and time
02:56 - What are your thoughts on the red dots as seen by James Webb Telescope
06:33 - A spacecraft called Link will boost the decaying orbit of the Swift satellite
14:08 - Is distant light redshifted? What happens to the lost energy
16:18 - Professor Fred Watson discusses Apollo 13 problems in Q and A edition
17:19 - Fenton from Minnesota has a question about the temperature on the moon
23:13 - European astrobiologist working on Roslyn Franklin rover on Mars
26:03 - Fred Watson asks what would happen if a white hole merged with a black hole
Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts-astronomy-insights-cosmic-discoveries--2631155/support.


00:00:00 --> 00:00:01 Andrew Dunkley: Hello again. Thank you for joining us on a Q

00:00:01 --> 00:00:04 and A edition of Space Nuts. This is where

00:00:04 --> 00:00:06 the audience asks us questions, we scratch

00:00:06 --> 00:00:08 our heads and it's all over in about a

00:00:08 --> 00:00:11 minute. Um, but, uh, if we are

00:00:11 --> 00:00:13 to answer questions, we may well, um,

00:00:14 --> 00:00:16 answer, um, the question as to how they're

00:00:16 --> 00:00:19 going to save the Swiss. Uh, the

00:00:19 --> 00:00:22 Swift Observatory, which as

00:00:22 --> 00:00:24 you might recall in a previous episode, was

00:00:24 --> 00:00:26 under threat of, um, you know, coming back

00:00:26 --> 00:00:28 into the Earth's atmosphere and being lost

00:00:28 --> 00:00:31 forever. Well, uh, James, who asked the

00:00:31 --> 00:00:32 question, is going to be in for a bit of a

00:00:32 --> 00:00:35 shock on that one. Uh, also a, uh, follow

00:00:35 --> 00:00:37 up on Redshift. We're going to look at

00:00:37 --> 00:00:40 temperatures of the moon and a white

00:00:40 --> 00:00:43 hole, black hole merger. What

00:00:43 --> 00:00:45 would be the effect? Fred Watson knows, we'll

00:00:45 --> 00:00:47 ask him on this edition of space

00:00:47 --> 00:00:48 nuts.

00:00:48 --> 00:00:51 Generic: 15 seconds. Guidance is internal.

00:00:51 --> 00:00:53 10, 9. Ignition

00:00:53 --> 00:00:54 sequence start.

00:00:54 --> 00:00:55 Professor Fred Watson: Uh, space nuts.

00:00:55 --> 00:00:58 Generic: 5, 4, 3, 2. 1, 2, 3, 4,

00:00:58 --> 00:01:00 5, 5, 4, 3, 2, 1.

00:01:00 --> 00:01:02 Andrew Dunkley: Space nuts.

00:01:02 --> 00:01:03 Generic: Astronauts report at Beales.

00:01:04 --> 00:01:07 Andrew Dunkley: And joining us to unrattle all of those

00:01:07 --> 00:01:10 rattling questions is Professor Fred Watson

00:01:10 --> 00:01:11 Watson, Astronomer at large. Hello,

00:01:11 --> 00:01:12 Fred Watson.

00:01:12 --> 00:01:14 Professor Fred Watson: Hello, Andrew. Fancy seeing you.

00:01:14 --> 00:01:17 Andrew Dunkley: Long time, long time no see. Yes,

00:01:17 --> 00:01:20 um, a question without notice.

00:01:20 --> 00:01:22 Do you always record on the same day and

00:01:22 --> 00:01:25 time? No, no, we

00:01:25 --> 00:01:28 don't. No. Uh, it's never that

00:01:28 --> 00:01:30 easy. That was an easy one to

00:01:30 --> 00:01:31 answer.

00:01:31 --> 00:01:33 Professor Fred Watson: Is that from our live, uh, audience?

00:01:33 --> 00:01:35 Andrew Dunkley: Yes, that's from Moose. G', Day, Moose.

00:01:36 --> 00:01:39 Yeah, but no, no, we don't. Um,

00:01:39 --> 00:01:41 it all comes down to who's available

00:01:42 --> 00:01:45 on whatever given day. And uh,

00:01:45 --> 00:01:47 today was the day. But, uh, no, it's, it's,

00:01:48 --> 00:01:50 it sort of jumps around sometimes we have to

00:01:50 --> 00:01:53 double up. In fact, um, this is the

00:01:53 --> 00:01:56 first time we've actually recorded together

00:01:56 --> 00:01:58 for over a month because Fred Watson

00:01:58 --> 00:02:01 was travelling and we had to double up

00:02:01 --> 00:02:04 for um, quite a few weeks to get ahead. And

00:02:04 --> 00:02:06 um, we didn't quite make it, which is why

00:02:06 --> 00:02:08 Jonty covered things for the last couple of

00:02:08 --> 00:02:11 weeks. But, uh, we generally try to do

00:02:11 --> 00:02:14 it in the morning so that we can catch the

00:02:14 --> 00:02:17 evening viewers in the United States, which

00:02:18 --> 00:02:20 works, um, out pretty well for most. But then

00:02:20 --> 00:02:22 most of the people in this part of the world

00:02:22 --> 00:02:22 are at work.

00:02:23 --> 00:02:25 Professor Fred Watson: So it's lose, lose.

00:02:25 --> 00:02:28 Andrew Dunkley: Basically can't cater for the entire world

00:02:28 --> 00:02:30 at one given moment. But that's, that's,

00:02:30 --> 00:02:32 that's the way it goes. If we could sort of

00:02:32 --> 00:02:34 just have one time zone with daylight

00:02:34 --> 00:02:35 everywhere all the time, it would make it

00:02:35 --> 00:02:37 easier. But, um, yeah, they're still working

00:02:37 --> 00:02:39 on that and I'm not joking, they are still

00:02:39 --> 00:02:41 working on that. They're trying to put up

00:02:41 --> 00:02:43 these big mirrors and I don't know what else.

00:02:43 --> 00:02:46 It's weird. Um, do you want to

00:02:46 --> 00:02:48 tackle some questions, Fred Watson?

00:02:49 --> 00:02:49 Professor Fred Watson: Yes, please.

00:02:49 --> 00:02:50 Andrew Dunkley: Thank you.

00:02:50 --> 00:02:53 Andrew Dunkley: Um, actually, we do have a live question

00:02:53 --> 00:02:55 straight up, so we'll might jump straight at

00:02:55 --> 00:02:56 that one.

00:02:56 --> 00:02:58 What are your thoughts on the red dots as

00:02:58 --> 00:03:00 seen by the James Webb Telescope?

00:03:00 --> 00:03:01 Professor Fred Watson: Asks.

00:03:01 --> 00:03:01 Andrew Dunkley: Good.

00:03:02 --> 00:03:04 Andrew Dunkley: Interestingly, they're in the news at the

00:03:04 --> 00:03:06 moment because, uh, there was a storey I only

00:03:06 --> 00:03:09 read just before we came on live to suggest

00:03:09 --> 00:03:12 that they think they're about to witness a

00:03:12 --> 00:03:13 red dot merger.

00:03:14 --> 00:03:16 Interestingly, yeah.

00:03:17 --> 00:03:19 Professor Fred Watson: So they're being well studied. Uh, and

00:03:20 --> 00:03:23 one of them in particular,

00:03:24 --> 00:03:27 uh, which has a name, I think it's called

00:03:27 --> 00:03:30 BH1. BH

00:03:31 --> 00:03:34 is an abbreviation for black hole star number

00:03:34 --> 00:03:36 one. Uh, and, um,

00:03:37 --> 00:03:40 this is a little red dot that, unlike many

00:03:40 --> 00:03:42 of the other ones, is in a

00:03:42 --> 00:03:45 relatively empty environment. So,

00:03:46 --> 00:03:48 uh, let's just recap. What are little red

00:03:48 --> 00:03:51 dots? They're what the penetrating power of

00:03:51 --> 00:03:53 the James Webb Telescope has revealed for the

00:03:53 --> 00:03:56 first time, uh, in the early universe, uh, at

00:03:56 --> 00:03:59 a time when the universe was only, you know,

00:03:59 --> 00:04:01 a few hundred million years old, we see these

00:04:01 --> 00:04:03 objects which have now got the name of little

00:04:03 --> 00:04:06 red dots. Um, they're compact,

00:04:06 --> 00:04:09 uh, and they are quite

00:04:09 --> 00:04:11 bright in terms of the amount of energy

00:04:12 --> 00:04:14 that they, uh, emit. And I think

00:04:15 --> 00:04:17 BH1, if I remember

00:04:17 --> 00:04:20 rightly, it's 100 billion times brighter

00:04:20 --> 00:04:23 than it should be. Whoa. Uh, and.

00:04:23 --> 00:04:25 But that's leading to

00:04:26 --> 00:04:29 the suggestion that what we're seeing here

00:04:30 --> 00:04:33 is a star, which, uh,

00:04:33 --> 00:04:36 is basically a cloud of gas with

00:04:36 --> 00:04:38 a supermassive black hole at its centre.

00:04:39 --> 00:04:42 So if you think about, uh, our knowledge of

00:04:42 --> 00:04:44 galaxies, most of which seem to have

00:04:44 --> 00:04:46 supermassive black holes at their centre,

00:04:46 --> 00:04:49 they're made of stars. Uh, that star

00:04:49 --> 00:04:51 formation process takes place over billions

00:04:51 --> 00:04:54 of years. Um, and we used to think that

00:04:54 --> 00:04:56 it took a long time for these black holes to

00:04:56 --> 00:04:59 become supermassive by, you know, them

00:04:59 --> 00:05:02 being basically, uh, gobbling up each other,

00:05:03 --> 00:05:05 uh, gobbling up material so that they became

00:05:05 --> 00:05:08 supermassive. But we see supermassive black

00:05:08 --> 00:05:10 holes now so early in the universe. And it

00:05:10 --> 00:05:12 looks as though BH

00:05:13 --> 00:05:15 got one at its centre. I think it's 50 or

00:05:15 --> 00:05:17 thereabouts times the mass of the sun. Can't

00:05:17 --> 00:05:19 remember the details. Um, I've had an

00:05:19 --> 00:05:22 operation since I read all that. Uh,

00:05:24 --> 00:05:27 so, um, um, the evidence seems

00:05:27 --> 00:05:29 to be that we are seeing a new class of

00:05:29 --> 00:05:32 object, uh, essentially a galaxy.

00:05:33 --> 00:05:35 Something not the size of a galaxy because

00:05:35 --> 00:05:37 Their dimensions are kind of solar system

00:05:37 --> 00:05:39 size. They're much bigger than the solar

00:05:39 --> 00:05:41 system, but they're clouds of gas.

00:05:42 --> 00:05:44 And we think that they are energised

00:05:45 --> 00:05:48 by the accretion disc. The way material is

00:05:48 --> 00:05:51 swirling around the black hole at their

00:05:51 --> 00:05:54 centre and that's raising temperatures in the

00:05:54 --> 00:05:56 middle to very high degrees until you get

00:05:56 --> 00:05:59 very high levels of energy emission, which is

00:05:59 --> 00:06:01 why they're said to be 100 billion times

00:06:01 --> 00:06:04 brighter than they should be. So it looks as

00:06:04 --> 00:06:06 though we're on the track of identifying

00:06:06 --> 00:06:08 these little red dots as something quite new

00:06:08 --> 00:06:11 and kind of unexpected. I'm sure they were

00:06:11 --> 00:06:14 predicted that we'd find, uh, stars

00:06:14 --> 00:06:17 made basically of nothing but gas in a black

00:06:17 --> 00:06:19 hole, uh, rather than, you know, other

00:06:19 --> 00:06:22 stars. Uh, and um, that

00:06:22 --> 00:06:25 seems to be what they are. So. Yeah, watch

00:06:25 --> 00:06:28 this. Space though. Um, you know.

00:06:29 --> 00:06:30 Yes, Moose, thanks.

00:06:30 --> 00:06:32 Andrew Dunkley: No, it wasn't Moose. It was good. Sorry, but

00:06:32 --> 00:06:33 thanks for the question.

00:06:33 --> 00:06:36 Uh, we've got an audio question now. This is

00:06:36 --> 00:06:37 from James.

00:06:37 --> 00:06:40 Andrew Dunkley: Hi, this is James in high western England.

00:06:41 --> 00:06:43 So as of 6 July, there's a

00:06:43 --> 00:06:46 spacecraft called Link which will boost the

00:06:46 --> 00:06:49 decaying orbit of the Swift satellite.

00:06:50 --> 00:06:53 What will it do to boost the orbit and what

00:06:53 --> 00:06:55 even does that mean, to boost an

00:06:55 --> 00:06:58 orbit? Um, I m. Guess I assume

00:06:58 --> 00:07:01 that pushing it from underneath might not

00:07:02 --> 00:07:04 be the answer. So look forward to

00:07:04 --> 00:07:07 hearing how it might actually do that.

00:07:07 --> 00:07:09 Thanks, James.

00:07:09 --> 00:07:11 Andrew Dunkley: Thank you, James. Hope all is well in, I

00:07:11 --> 00:07:13 think you said, Howick in the uk.

00:07:13 --> 00:07:14 Professor Fred Watson: High Wycombe.

00:07:14 --> 00:07:15 Andrew Dunkley: High Wycombe.

00:07:15 --> 00:07:16 Andrew Dunkley: All right.

00:07:16 --> 00:07:17 Andrew Dunkley: Okay. Could have been either.

00:07:19 --> 00:07:22 Um, We've got some bad news for you, James,

00:07:22 --> 00:07:23 I'm afraid, haven't we, Fred Watson?

00:07:24 --> 00:07:26 Professor Fred Watson: Yeah. So, uh,

00:07:27 --> 00:07:30 it's really sad because, um, this

00:07:31 --> 00:07:34 project has been a bit of a poster child

00:07:34 --> 00:07:37 for NASA because normally their projects take

00:07:37 --> 00:07:39 decades to come into fruition. But

00:07:40 --> 00:07:42 they tasked company, uh,

00:07:43 --> 00:07:46 something like a. With a year's notice or

00:07:46 --> 00:07:48 something, uh, to develop

00:07:49 --> 00:07:51 a spacecraft, uh, and actually

00:07:53 --> 00:07:56 um, basically work out how you could rescue

00:07:56 --> 00:07:59 the Swift spacecraft. So the storey is Swift

00:07:59 --> 00:08:02 is uh, an elderly SpaceCraft

00:08:02 --> 00:08:05 launched in 2004 to study gamma ray

00:08:05 --> 00:08:07 bursts. But it's been so successful,

00:08:07 --> 00:08:10 uh, that there was a uh, real

00:08:10 --> 00:08:13 uh, I guess desire to uh, to save

00:08:13 --> 00:08:16 it because its orbit is decaying.

00:08:16 --> 00:08:19 And as of later this year we expect

00:08:19 --> 00:08:22 it, Its orbit will actually get

00:08:22 --> 00:08:24 so much atmospheric drag that it will decay

00:08:24 --> 00:08:27 very quickly and the spacecraft, the Swift

00:08:27 --> 00:08:29 spacecraft will burn up in the atmosphere.

00:08:30 --> 00:08:32 So, um, the Link mission, uh,

00:08:32 --> 00:08:35 was a joint, um, project

00:08:35 --> 00:08:38 between NASA and a company called

00:08:38 --> 00:08:40 Catalyst, Catalyst Space. Uh,

00:08:40 --> 00:08:43 and indeed the Link spacecraft was launched

00:08:43 --> 00:08:44 on July 3

00:08:46 --> 00:08:49 with every intention of rendezvousing with

00:08:49 --> 00:08:52 the Swift spacecraft and lifting its orbit.

00:08:52 --> 00:08:54 And I'll get onto that in a minute because

00:08:54 --> 00:08:56 that's basically James's question.

00:08:57 --> 00:08:59 But what happened was um, they had an

00:08:59 --> 00:09:02 attitude control issue. Uh,

00:09:02 --> 00:09:05 and so very quickly the,

00:09:05 --> 00:09:08 and probably within weeks link, uh,

00:09:09 --> 00:09:11 the spacecraft that was going to save Swift

00:09:11 --> 00:09:13 just started tumbling out of control.

00:09:14 --> 00:09:17 Um, and we got an announcement uh,

00:09:17 --> 00:09:20 very soon after that that the spacecraft

00:09:20 --> 00:09:22 would not capture or boost the Swift

00:09:22 --> 00:09:24 satellite's altitude as planned.

00:09:25 --> 00:09:27 Um, I think

00:09:28 --> 00:09:30 they're still attempting

00:09:31 --> 00:09:34 to rendezvous with Swift. In other

00:09:34 --> 00:09:37 words to bring the Link spacecraft close to

00:09:37 --> 00:09:39 Swift just to cheque that

00:09:39 --> 00:09:42 all their capabilities in terms of

00:09:42 --> 00:09:45 rendezvous uh, are working. But

00:09:45 --> 00:09:47 because of this out of control tumbling,

00:09:48 --> 00:09:50 um, they're not going to be able to do

00:09:50 --> 00:09:52 anything on that. Um,

00:09:53 --> 00:09:56 so um, it's turning into a

00:09:56 --> 00:09:59 mission that is a face saving mission in a

00:09:59 --> 00:10:01 way. Uh, there is a nice piece on

00:10:02 --> 00:10:05 our own friend Universe today. Uh, they've

00:10:05 --> 00:10:07 got a nice piece on it called NASA Announces

00:10:07 --> 00:10:10 Next Steps for Swift Rescue Mission. And it

00:10:10 --> 00:10:12 has a lot of quotes from uh, people like

00:10:13 --> 00:10:15 uh, the NASA administrator Jared Isaacman,

00:10:15 --> 00:10:18 uh, and, and other people involved, uh,

00:10:18 --> 00:10:20 Catalyst Space have released a statement,

00:10:21 --> 00:10:24 um, all of which is you know, basically

00:10:24 --> 00:10:26 saying that they, they'd hope for more

00:10:26 --> 00:10:29 science from Swift. Um, I think

00:10:29 --> 00:10:32 this is a comment from Sean

00:10:32 --> 00:10:34 Domagal Goldman who's Director of

00:10:34 --> 00:10:37 Astrophysics at NASA, uh, who says we were

00:10:37 --> 00:10:39 all hoping for more science from Swift, but

00:10:39 --> 00:10:41 we knew the takeaways from this mission would

00:10:41 --> 00:10:43 be worthwhile either way. We've gained so

00:10:43 --> 00:10:45 much through the series of accomplishments up

00:10:45 --> 00:10:47 to this point. Building, testing and

00:10:47 --> 00:10:49 operating. This mission has already

00:10:49 --> 00:10:51 strengthened America's space industry

00:10:51 --> 00:10:53 pipeline, advancing in space

00:10:54 --> 00:10:56 servicing capabilities in completely new

00:10:56 --> 00:10:58 ways. And I think that's a reflection of the

00:10:58 --> 00:11:00 fact that this was all done in double quick

00:11:00 --> 00:11:03 time. Uh, even though it's in the end not

00:11:03 --> 00:11:06 succeeded, um, it has been um, a

00:11:06 --> 00:11:08 mission from which people have learned a lot.

00:11:08 --> 00:11:11 So just going back to James's question, how

00:11:11 --> 00:11:14 do you boost uh, the

00:11:14 --> 00:11:16 orbit or increase the orbit of a spacecraft?

00:11:17 --> 00:11:19 Uh, what you have to do is you have to

00:11:19 --> 00:11:22 increase its velocity. And so

00:11:22 --> 00:11:24 um, what I think the Link

00:11:24 --> 00:11:27 spacecraft would have done would have been

00:11:27 --> 00:11:29 and I think it had three arms that could

00:11:29 --> 00:11:32 grapple onto Swift ont

00:11:32 --> 00:11:35 hard points on Swift's sort of

00:11:35 --> 00:11:36 fuselage, what they call the bus, the main

00:11:36 --> 00:11:39 part of the satellite. So I think it was

00:11:39 --> 00:11:41 three that it will grab hold of and then you

00:11:41 --> 00:11:43 use the link, uh thrusters

00:11:44 --> 00:11:47 to apply a velocity or

00:11:47 --> 00:11:50 an acceleration uh, essentially in the

00:11:50 --> 00:11:52 direction of travel. Uh, because remember,

00:11:52 --> 00:11:54 all satellites are essentially travelling

00:11:54 --> 00:11:57 horizontally. They're all moving in

00:11:57 --> 00:12:00 orbits that are parallel to the Earth. Of

00:12:00 --> 00:12:01 course, it's the fact that there's a sphere

00:12:01 --> 00:12:04 that means the orbit is a circ. Um, so what

00:12:04 --> 00:12:06 you do is you boost its

00:12:06 --> 00:12:09 velocity. And what that does is

00:12:09 --> 00:12:12 it raises what we call the apogee.

00:12:13 --> 00:12:15 So it elongates the ellipse

00:12:15 --> 00:12:18 that the spacecraft

00:12:18 --> 00:12:21 orbit is in. Um, so

00:12:21 --> 00:12:23 you boost its velocity and

00:12:23 --> 00:12:26 you get an extended ellipse. And the near

00:12:26 --> 00:12:28 part of the ellipse, what we call perigee,

00:12:28 --> 00:12:31 the part closest to the earth, sort of where

00:12:31 --> 00:12:32 you started from, that's still at the same

00:12:32 --> 00:12:35 height, but you've given the far part,

00:12:35 --> 00:12:37 um, the apogee a much higher

00:12:38 --> 00:12:40 radius. And then what you do is,

00:12:41 --> 00:12:44 uh, at the apogee, you

00:12:44 --> 00:12:46 boost it again, you boost the velocity again.

00:12:46 --> 00:12:49 And that lifts the perigee, that actually

00:12:49 --> 00:12:51 lifts the near point. So it's a two step

00:12:51 --> 00:12:53 process. Uh, but it's all about just

00:12:53 --> 00:12:55 increasing the velocity of the spacecraft.

00:12:55 --> 00:12:58 And that automatically lifts the orbit,

00:12:58 --> 00:13:00 uh, in a way that I've described.

00:13:00 --> 00:13:03 Andrew Dunkley: That's how it works in theory, James. It

00:13:03 --> 00:13:05 unfortunately didn't happen. The rescue

00:13:05 --> 00:13:08 missions failed. But uh, the good news news

00:13:08 --> 00:13:10 is Swift will continue to operate. Uh,

00:13:10 --> 00:13:13 they've restarted um, its observations,

00:13:14 --> 00:13:16 uh, but it is in a very rapid

00:13:17 --> 00:13:20 decaying orbit. And they expect re

00:13:20 --> 00:13:23 entry late, uh, well, not so long

00:13:23 --> 00:13:25 now. Late this year.

00:13:25 --> 00:13:25 Andrew Dunkley: Late.

00:13:26 --> 00:13:29 Andrew Dunkley: We're entering late this year already. So we

00:13:29 --> 00:13:29 are.

00:13:29 --> 00:13:31 Professor Fred Watson: That's right. Yeah. I don't think it's much

00:13:31 --> 00:13:31 longer.

00:13:31 --> 00:13:33 Andrew Dunkley: I only got a couple of months to live.

00:13:33 --> 00:13:35 Unfortunately they couldn't save it. But um,

00:13:35 --> 00:13:38 yeah, I

00:13:38 --> 00:13:41 guess they were very hopeful. But um,

00:13:41 --> 00:13:44 it was a pretty last minute thing to try and

00:13:44 --> 00:13:46 do and um, it just didn't work out,

00:13:47 --> 00:13:50 unfortunately. Got um, a

00:13:50 --> 00:13:52 message from Europe as well. Someone's up at

00:13:52 --> 00:13:54 4am and I asked why and he said my little

00:13:54 --> 00:13:56 toddler woke me up. They do that.

00:13:57 --> 00:14:00 They do that. But um, anyway, glad you found

00:14:00 --> 00:14:03 us. Uh, thank you James for the question.

00:14:03 --> 00:14:05 Uh, we'll move straight onto our next

00:14:05 --> 00:14:08 question from Dale, who's in New Zealand.

00:14:08 --> 00:14:10 Uh, he's referring to a question that came

00:14:10 --> 00:14:12 from Roger the trucker, which uh, I think we

00:14:12 --> 00:14:15 covered a few weeks ago. Um, who asked?

00:14:15 --> 00:14:18 Is distant light redshifted? What happens

00:14:18 --> 00:14:21 to the lost energy? And Dale says

00:14:21 --> 00:14:24 surely no energy is lost. Isn't it just

00:14:24 --> 00:14:25 stretched?

00:14:27 --> 00:14:30 Professor Fred Watson: Yes, that's right. So, excuse me, but

00:14:30 --> 00:14:32 longer wavelength, which is what you stretch

00:14:32 --> 00:14:35 it into, um, means,

00:14:36 --> 00:14:39 um, means that the energy that's

00:14:39 --> 00:14:42 carried is less. Uh, and

00:14:42 --> 00:14:45 I guess it's like, you know,

00:14:45 --> 00:14:48 the particle wave duality. The

00:14:48 --> 00:14:50 fact that we can think of light as both a

00:14:50 --> 00:14:53 particle and as a wave. You can think of it

00:14:53 --> 00:14:55 as a particle with certain energy, a photon,

00:14:55 --> 00:14:57 uh, or you can think of it as a wave with a

00:14:57 --> 00:14:59 certain wavelength. And the longer the

00:14:59 --> 00:15:01 wavelength, the lower the energy. So we talk

00:15:01 --> 00:15:04 about high energy astrophysics as being

00:15:04 --> 00:15:06 things that. Where we use gamma rays and X

00:15:06 --> 00:15:08 rays to. To probe space.

00:15:09 --> 00:15:12 So, um, I do remember we

00:15:12 --> 00:15:15 looked at this question and got a number of

00:15:15 --> 00:15:18 different answers. Um, most of

00:15:18 --> 00:15:20 which were don't worry about it.

00:15:22 --> 00:15:25 Which is kind of, uh, what our listener

00:15:25 --> 00:15:28 is, uh, saying, don't worry about it.

00:15:28 --> 00:15:29 It'll be all right. Um,

00:15:32 --> 00:15:34 there is a suggestion that some of that

00:15:34 --> 00:15:37 energy, uh, effectively goes

00:15:37 --> 00:15:38 into raising the background temperature of

00:15:38 --> 00:15:41 the universe. By a tiny gazillionth of

00:15:41 --> 00:15:44 a degree. Uh, but there's another point of

00:15:44 --> 00:15:46 view. It's interesting. It's worth, um, you

00:15:46 --> 00:15:48 know, having a look and, uh. Going down the

00:15:48 --> 00:15:50 rabbit hole. I, uh, haven't had time to do

00:15:50 --> 00:15:53 that again. Um, but, um.

00:15:53 --> 00:15:55 Uh, yeah, go down the rabbit hole and have a

00:15:55 --> 00:15:57 look at what people think about the energy

00:15:57 --> 00:16:00 loss, uh, from, um. The redshift

00:16:00 --> 00:16:02 energy is lost. It goes somewhere, uh,

00:16:02 --> 00:16:05 because the universe is a closed system. Uh,

00:16:05 --> 00:16:08 um. My understanding, as it was always. That

00:16:08 --> 00:16:09 it basically heats the cosmic microwave

00:16:09 --> 00:16:11 background very, very slightly.

00:16:12 --> 00:16:14 Andrew Dunkley: That makes sense, yes. Hope that answers your

00:16:14 --> 00:16:16 question, Dale. Thanks for sending it in and

00:16:16 --> 00:16:17 hope all is well in New Zealand.

00:16:18 --> 00:16:21 This is space nuts. Andrew Dunkley here on a

00:16:21 --> 00:16:23 Q and A edition with Professor Fred Watson

00:16:23 --> 00:16:23 Watson.

00:16:26 --> 00:16:28 Okay, Houston, we've had a problem here.

00:16:28 --> 00:16:28 Generic: This is Houston.

00:16:28 --> 00:16:30 Andrew Dunkley: Say again, please. Houston, we've had about.

00:16:30 --> 00:16:32 We've had a main B plus undervolt. Roger,

00:16:32 --> 00:16:35 main B undervolt. Okay, standby 13. We're

00:16:35 --> 00:16:37 looking at it, Stacey, but I'm going to let a

00:16:37 --> 00:16:39 cat out of a bag here, Fred Watson. In my,

00:16:39 --> 00:16:42 um, new trilogy that. It's just

00:16:42 --> 00:16:44 been released and I think I've sold one copy.

00:16:45 --> 00:16:48 Um, the main B bus

00:16:48 --> 00:16:50 undervolt problem on Apollo 13.

00:16:50 --> 00:16:51 Professor Fred Watson: All right.

00:16:51 --> 00:16:53 Andrew Dunkley: I used that in. I used that in one of the

00:16:53 --> 00:16:55 books just for fun.

00:16:56 --> 00:16:56 Professor Fred Watson: Love it.

00:16:57 --> 00:16:58 Andrew Dunkley: Yeah.

00:16:58 --> 00:17:00 Professor Fred Watson: Anyway, it's nice to put these little, little

00:17:00 --> 00:17:02 snippets in. I've done that in a few of my

00:17:02 --> 00:17:05 books that put things in it that probably I'm

00:17:05 --> 00:17:07 the only person would know that I was

00:17:07 --> 00:17:08 alluding something else.

00:17:08 --> 00:17:11 Andrew Dunkley: I do it a lot. I think I've done it a few

00:17:11 --> 00:17:13 times in this series. Just for fun. And the

00:17:13 --> 00:17:15 people who know will know. The people who

00:17:15 --> 00:17:17 don't will just keep reading and it'll just

00:17:17 --> 00:17:18 be part of the storey, so. That's right,

00:17:19 --> 00:17:19 yeah.

00:17:19 --> 00:17:22 Um, let's go to our next question from one of

00:17:22 --> 00:17:24 our regular, uh, contributors. Here is Fred.

00:17:25 --> 00:17:28 Andrew Dunkley: Hello, friend. And Andrew. This is

00:17:28 --> 00:17:30 Fred calling you from

00:17:30 --> 00:17:32 Minnesota. Thank you for your podcast.

00:17:33 --> 00:17:36 I never miss an episode for it. I have

00:17:36 --> 00:17:39 a question for you about the temperature

00:17:39 --> 00:17:42 on the moon. Now, it's well

00:17:42 --> 00:17:45 known that the temperature on the surface

00:17:45 --> 00:17:48 swings greatly with the orbit of the

00:17:48 --> 00:17:51 moon. But what about underneath

00:17:51 --> 00:17:53 the moon as below its surface?

00:17:54 --> 00:17:57 How constant is it? Does it also

00:17:57 --> 00:17:59 swing around? Does it matter how deep

00:17:59 --> 00:18:02 you go underneath the moon?

00:18:03 --> 00:18:05 This has, of course, relevance

00:18:06 --> 00:18:08 to putting people on the moon and living

00:18:09 --> 00:18:11 on them. Thank you very much

00:18:12 --> 00:18:13 for the question. Bye now.

00:18:14 --> 00:18:16 Andrew Dunkley: Thank you, Fred. He brings up a really good

00:18:16 --> 00:18:19 point. We are going to have people spending

00:18:19 --> 00:18:21 time on the moon in the not too distant

00:18:21 --> 00:18:23 future and some of them will, you know,

00:18:23 --> 00:18:26 they're not just going to go up and kick the

00:18:26 --> 00:18:27 sand and then come home again like you do

00:18:27 --> 00:18:29 when you go to the beach. They'll be up there

00:18:29 --> 00:18:32 for a decent period of time. Um,

00:18:32 --> 00:18:35 I'd say rotating rosters of weeks or

00:18:35 --> 00:18:37 whatever. Uh, how are they going to deal with

00:18:37 --> 00:18:39 these temperatures? Because, uh, as far as I

00:18:39 --> 00:18:42 recall, the moon is one of

00:18:42 --> 00:18:45 the coldest places in the solar system, is it

00:18:45 --> 00:18:46 not?

00:18:47 --> 00:18:49 Professor Fred Watson: And the warmest as well. Um, it's

00:18:49 --> 00:18:51 temperature variation. I always get these

00:18:51 --> 00:18:54 figures wrong, but it's almost a 300 degree

00:18:54 --> 00:18:56 Celsius variation from minus

00:18:56 --> 00:18:59 150 to plus 150. They're slightly different.

00:18:59 --> 00:19:00 Andrew Dunkley: Just like Dubbo.

00:19:03 --> 00:19:05 Professor Fred Watson: Yes, it's a lot like Dubbo.

00:19:06 --> 00:19:09 Andrew Dunkley: No, I think our temperature variations are

00:19:09 --> 00:19:12 somewhere around 50 degrees, but it's still.

00:19:12 --> 00:19:14 Professor Fred Watson: Yeah, that's right. That's remarkable.

00:19:14 --> 00:19:14 Andrew Dunkley: Celsius.

00:19:14 --> 00:19:17 Professor Fred Watson: Um, 50. Celsius. Yes.

00:19:17 --> 00:19:19 What's your lowest that you've ever had?

00:19:20 --> 00:19:22 Andrew Dunkley: Minus 7.4, I think.

00:19:23 --> 00:19:25 Which was only a couple of years ago. Yeah,

00:19:25 --> 00:19:28 yep, something like that.

00:19:29 --> 00:19:31 Quite. Our warmest is 40.

00:19:32 --> 00:19:35 No, we got to 50 the year before last.

00:19:36 --> 00:19:38 So, uh, there you go, it's 50. 50. Nearly 58

00:19:38 --> 00:19:40 degrees variation.

00:19:41 --> 00:19:43 Professor Fred Watson: Yeah, yeah. Eat your heart out, Moon.

00:19:44 --> 00:19:47 Because the moon's much higher. And

00:19:47 --> 00:19:49 of course the reason for that is that there's

00:19:49 --> 00:19:52 no atmosphere. So during the day you've got

00:19:52 --> 00:19:55 the sun's radiation beaming down, heating the

00:19:55 --> 00:19:57 surface. And, uh, it's the surf temperature

00:19:57 --> 00:19:59 that we talk about when we mean these things.

00:19:59 --> 00:20:02 Well over 100 degrees and at night that just

00:20:02 --> 00:20:04 all radiates into space, um, and

00:20:05 --> 00:20:07 the surface cools to minus 100

00:20:08 --> 00:20:10 and something degrees as well. I can't

00:20:10 --> 00:20:11 remember that. I can never remember the exact

00:20:11 --> 00:20:13 figures. I should have them in my head. But

00:20:14 --> 00:20:16 the good news is, and I think, you know, this

00:20:16 --> 00:20:19 is what Fred's alluding to is that

00:20:20 --> 00:20:22 the, the lunar soil

00:20:23 --> 00:20:26 um, is very poor. It's a very poor

00:20:26 --> 00:20:29 conductor of heat. Ah, and

00:20:29 --> 00:20:32 so that means that, you know, you don't have

00:20:32 --> 00:20:34 to go down

00:20:35 --> 00:20:38 too far to find that those temperatures

00:20:38 --> 00:20:41 even out quite a bit. I'm reading

00:20:41 --> 00:20:44 from um, from a, um, an article

00:20:44 --> 00:20:46 actually on lunar surface temperature. Uh,

00:20:46 --> 00:20:49 I'm going to quote from it. Measurements from

00:20:50 --> 00:20:52 the Apollo 15 and 17

00:20:52 --> 00:20:55 missions show that temperatures

00:20:55 --> 00:20:58 35 centimetres below the surface, that's ah,

00:20:58 --> 00:21:01 not much more than a foot, are ah, 40 to

00:21:01 --> 00:21:03 45 degrees Kelvin,

00:21:03 --> 00:21:06 warmer than the minimum

00:21:06 --> 00:21:09 surface nighttime temperature, avoiding the

00:21:09 --> 00:21:11 harshest cold. So it brings the

00:21:11 --> 00:21:14 temperature up and that's only a foot or so

00:21:14 --> 00:21:17 below the surface. And then continuing the

00:21:17 --> 00:21:19 same article, um, by the time you

00:21:19 --> 00:21:22 get to getting on for a metre, 80

00:21:22 --> 00:21:25 centimetres, 30 inches if you prefer

00:21:25 --> 00:21:28 that below the surface the

00:21:29 --> 00:21:32 day and night variations are

00:21:32 --> 00:21:35 uh, imperceptible. So that

00:21:35 --> 00:21:37 is incredible really that you've only

00:21:37 --> 00:21:40 got to go um, you know,

00:21:40 --> 00:21:43 80 centimetres less than a metre below the

00:21:43 --> 00:21:46 surface and the material there

00:21:46 --> 00:21:48 does not see these enormous

00:21:48 --> 00:21:51 swings in temperature. Uh, it's become

00:21:51 --> 00:21:54 imperceptible. Um, and then

00:21:54 --> 00:21:57 when you get to below a metre, um,

00:21:58 --> 00:22:01 then you get an average temperature which is

00:22:01 --> 00:22:02 kind of the average of the hottest and the

00:22:02 --> 00:22:05 coldest. And that is very nice because it

00:22:05 --> 00:22:07 makes it about 20 degrees Celsius

00:22:07 --> 00:22:09 or um, you know,

00:22:10 --> 00:22:13 that sort of basically that uh,

00:22:14 --> 00:22:16 20 degrees Celsius is.

00:22:17 --> 00:22:19 I beg your pardon, it's minus 20 degrees

00:22:19 --> 00:22:22 Celsius, not 20 degrees but still

00:22:22 --> 00:22:25 within reason. Um, and so

00:22:26 --> 00:22:29 it means that if you can look for caves

00:22:29 --> 00:22:32 and pits in the lunar, uh,

00:22:32 --> 00:22:35 regolith in the lunar soil then

00:22:35 --> 00:22:38 you've got a really good chance of having a

00:22:38 --> 00:22:41 place where you've got, without any air

00:22:41 --> 00:22:43 conditioning or anything. You've got a

00:22:43 --> 00:22:46 ready temperature round about 17

00:22:46 --> 00:22:48 degrees Celsius, uh, day and night

00:22:49 --> 00:22:52 without these extremes. So um, that's

00:22:52 --> 00:22:55 really good news. I think from the

00:22:55 --> 00:22:57 perspective of our future exploration of the

00:22:57 --> 00:23:00 moon, uh, that this variation uh,

00:23:01 --> 00:23:03 is only on the surface. The extreme

00:23:04 --> 00:23:05 variation is only on the surface itself.

00:23:06 --> 00:23:09 Andrew Dunkley: M There you go Fred. So good question, thanks

00:23:09 --> 00:23:12 for asking it. Uh, and uh, great to hear from

00:23:12 --> 00:23:12 you again.

00:23:13 --> 00:23:15 Uh, our European listener whose

00:23:15 --> 00:23:18 toddler woke them up at 4am has sent us a

00:23:18 --> 00:23:21 note Saying he's an astrobiologist working in

00:23:21 --> 00:23:24 the ExoMars science team. Uh,

00:23:24 --> 00:23:26 he's a big fan of the show and I thought,

00:23:26 --> 00:23:28 oh, I'm going to look this up. ExoMars, uh,

00:23:29 --> 00:23:32 science team, uh, is um,

00:23:32 --> 00:23:35 looking into ExoMars, uh, missions,

00:23:38 --> 00:23:40 uh, particularly in um,

00:23:41 --> 00:23:44 part, uh, working on the uh, Roslyn Franklin

00:23:44 --> 00:23:47 rover. And they're trying to find out

00:23:47 --> 00:23:49 did Mars ever have life and could traces of

00:23:49 --> 00:23:52 it still be preserved underground. So um, I

00:23:52 --> 00:23:55 looked that up and since then another note's

00:23:55 --> 00:23:58 come through. Our Rover has a 2 metre drill

00:23:58 --> 00:24:00 to get samples from Mars. Uh, subsurface

00:24:00 --> 00:24:03 organics will be preserved. Um,

00:24:03 --> 00:24:05 what do you think will we find? And

00:24:05 --> 00:24:08 biosignatures, always throwing you a

00:24:08 --> 00:24:09 curvy there.

00:24:10 --> 00:24:12 Professor Fred Watson: The trouble is it's knowing that they are

00:24:12 --> 00:24:15 biosignatures. Yes, he or she, uh.

00:24:15 --> 00:24:18 Well, look, an honour to have somebody uh,

00:24:18 --> 00:24:20 working right in the front line of this

00:24:20 --> 00:24:23 stuff, particularly in Europe, very close to

00:24:23 --> 00:24:25 my heart. Uh, it's an honour to have you

00:24:25 --> 00:24:28 listening and um, participating in the show.

00:24:28 --> 00:24:29 Thank you very much. Um,

00:24:31 --> 00:24:33 the issue with biosignatures is are

00:24:33 --> 00:24:36 they biosignatures or are there false alarms?

00:24:36 --> 00:24:38 And it is so difficult

00:24:39 --> 00:24:42 to essentially eliminate everything

00:24:42 --> 00:24:45 else that could be causing whatever that

00:24:45 --> 00:24:46 biosignature is, whether it's uh,

00:24:47 --> 00:24:50 microbial structure or uh,

00:24:50 --> 00:24:53 metabolic activity or whatever it is. It's

00:24:53 --> 00:24:56 very hard to eliminate what you might call

00:24:56 --> 00:24:59 natural, non biological, uh, origins.

00:24:59 --> 00:25:02 But digging deep is the way to go. Uh,

00:25:02 --> 00:25:05 I think the ExoMars project has

00:25:05 --> 00:25:08 had mixed fortunes because it was originally

00:25:09 --> 00:25:11 uh, going to be uh, a joint

00:25:11 --> 00:25:14 European Russian project, um,

00:25:14 --> 00:25:16 which I think was shelved probably at the

00:25:16 --> 00:25:19 time of the invasion of Crimea in

00:25:19 --> 00:25:22 2014. I think that's what happened. Um,

00:25:22 --> 00:25:25 and so, um, But I think Europe

00:25:25 --> 00:25:27 is carrying on its own,

00:25:28 --> 00:25:31 uh, I wish, uh, uh, our listeners and

00:25:31 --> 00:25:33 everybody working with them every success,

00:25:33 --> 00:25:35 uh, because these are things we want to know.

00:25:35 --> 00:25:38 Andrew Dunkley: Yeah, absolutely. Uh, Issa says the rover

00:25:38 --> 00:25:41 will target an ancient clay rich region where

00:25:41 --> 00:25:43 minerals formed in the presence of abundant

00:25:43 --> 00:25:46 liquid water and could have preserved

00:25:46 --> 00:25:47 evidence of ancient life. And their launch

00:25:48 --> 00:25:51 window is set for late

00:25:51 --> 00:25:53 2028 at this stage. So. Yes,

00:25:54 --> 00:25:55 fingers crossed. That'll be exciting. Looking

00:25:55 --> 00:25:57 forward to that. Thanks for letting us know.

00:26:00 --> 00:26:01 Generic: Roger, in your labs right here.

00:26:01 --> 00:26:02 Andrew Dunkley: Also space nuts.

00:26:03 --> 00:26:05 Final question, Fred Watson. This comes from

00:26:05 --> 00:26:08 Kevin. So, uh, this is uh, going to be more

00:26:08 --> 00:26:11 of a hypothetical. I understand we have no

00:26:11 --> 00:26:13 observational evidence of white holes, but we

00:26:13 --> 00:26:16 do have a fair mathematical understanding of

00:26:16 --> 00:26:19 them. So my question is if a white hole

00:26:19 --> 00:26:21 actually existed, what would happen

00:26:22 --> 00:26:24 if it Merged with a black hole. Would they

00:26:24 --> 00:26:26 essentially cancel each other out? What

00:26:26 --> 00:26:29 would, would be left afterwards? Just, uh,

00:26:29 --> 00:26:31 some random thoughts. I was thinking, uh, and

00:26:31 --> 00:26:34 would love some insight on what you guys

00:26:34 --> 00:26:36 think. Amazing show. Keep up the great work,

00:26:36 --> 00:26:38 Kevin. I know the answer to this one,

00:26:38 --> 00:26:38 Fred Watson.

00:26:39 --> 00:26:41 Professor Fred Watson: Good, good. It would

00:26:41 --> 00:26:44 be a grey hole. Uh, well,

00:26:44 --> 00:26:47 that's. Could be right. My mind

00:26:47 --> 00:26:50 went straight to when a black hole and a

00:26:50 --> 00:26:52 Whitehall love each other very much.

00:26:52 --> 00:26:53 Andrew Dunkley: Oh, boy.

00:26:53 --> 00:26:53 Professor Fred Watson: Then they

00:26:56 --> 00:26:58 come together and make a grey hole. How's

00:26:58 --> 00:27:01 that? Ah, yeah, um, that's a

00:27:01 --> 00:27:03 good question. And I, Sorry, I'm,

00:27:04 --> 00:27:06 I'm still a little bit, um,

00:27:06 --> 00:27:08 unprepared for these, um,

00:27:09 --> 00:27:11 because my focus is on making my knee better.

00:27:12 --> 00:27:15 But, uh, I would like to cheque that out and

00:27:15 --> 00:27:17 see what the pundits think. In the world of

00:27:17 --> 00:27:19 black holes and white holes, we've never seen

00:27:19 --> 00:27:22 any evidence for a white hole. Um, you

00:27:22 --> 00:27:25 can create a white hole

00:27:25 --> 00:27:28 mathematically, uh, by reversing the

00:27:28 --> 00:27:31 time, uh, factor in the equations of

00:27:31 --> 00:27:33 relativity, and then you get a white hole

00:27:33 --> 00:27:35 rather than a black hole. But that does not

00:27:35 --> 00:27:37 mean that they exist. We do know that black

00:27:37 --> 00:27:40 holes exist. The evidence for their existence

00:27:40 --> 00:27:43 is absolutely compelling. Um,

00:27:43 --> 00:27:46 I, you know, the idea of them cancelling out

00:27:46 --> 00:27:49 is the one that has the most appeal, because

00:27:49 --> 00:27:51 that sounds feasible. Gravitational wells.

00:27:51 --> 00:27:53 Yeah. Of different kinds of,

00:27:54 --> 00:27:57 uh. But I, I, That's a flippant comment. I'll

00:27:57 --> 00:27:59 need to look at this again. Perhaps you can

00:27:59 --> 00:28:01 remind me until we can get back to Kevin, uh,

00:28:01 --> 00:28:04 and talk about what happens when you get a

00:28:04 --> 00:28:04 grey hole.

00:28:05 --> 00:28:08 Andrew Dunkley: Yeah. Um, I think you end up

00:28:08 --> 00:28:09 in a, uh, retirement village.

00:28:09 --> 00:28:10 Professor Fred Watson: Sure.

00:28:14 --> 00:28:16 Andrew Dunkley: And Moose says, aren't white holes still

00:28:16 --> 00:28:18 theory only? Yes, absolutely.

00:28:18 --> 00:28:19 Professor Fred Watson: That's right. Absolutely right.

00:28:21 --> 00:28:22 Andrew Dunkley: It's like many things in the universe, the

00:28:22 --> 00:28:25 mathematics says, yes, they could exist,

00:28:26 --> 00:28:28 um, but we've never seen them and

00:28:29 --> 00:28:31 we don't have any other proof, so.

00:28:31 --> 00:28:32 Professor Fred Watson: Quite fun.

00:28:32 --> 00:28:35 Andrew Dunkley: Yes, indeed. Uh, thanks for the question,

00:28:35 --> 00:28:37 Kevin. Thanks to everybody who contributed.

00:28:37 --> 00:28:39 Thanks to our live audience who contributed

00:28:39 --> 00:28:41 today. Lovely to hear from you. I think

00:28:41 --> 00:28:44 that's the most active it's ever been. So

00:28:44 --> 00:28:46 it's, uh, value added to the show. We really

00:28:46 --> 00:28:48 appreciate it. And thank you, Fred Watson.

00:28:48 --> 00:28:51 Professor Fred Watson: Uh, as always, it's a pleasure,

00:28:51 --> 00:28:54 Andrew. I hope next time we speak my

00:28:54 --> 00:28:57 knee will be just slightly more tractable

00:28:57 --> 00:28:59 than it is at the moment as the months wear

00:28:59 --> 00:29:02 on and I get back to being 100%

00:29:03 --> 00:29:05 mobile again, which I'm looking forward to.

00:29:05 --> 00:29:07 Andrew Dunkley: Fingers crossed. Good to have you back too.

00:29:07 --> 00:29:08 Professor Fred Watson: Thank you.

00:29:08 --> 00:29:10 Andrew Dunkley: Professor Fred Watson Watson, astronomer at

00:29:10 --> 00:29:12 large. And don't, uh, forget to visit us

00:29:12 --> 00:29:14 online where you can leave questions on the

00:29:14 --> 00:29:16 AMA button at the top. Um, text or audio

00:29:16 --> 00:29:18 questions. Don't forget to tell us who you

00:29:18 --> 00:29:20 are or where you're from and please leave

00:29:20 --> 00:29:22 reviews wherever you listen to us, us. And,

00:29:22 --> 00:29:24 um, have a look around on our website while

00:29:24 --> 00:29:26 you're there and see what else you can find

00:29:26 --> 00:29:29 to, uh, keep you amused between

00:29:29 --> 00:29:31 episodes. And uh, thanks to Huw in the studio

00:29:31 --> 00:29:34 who couldn't be with us today because, um,

00:29:34 --> 00:29:37 like many things in the universe, his

00:29:37 --> 00:29:40 existence is just theoretical. And from me,

00:29:40 --> 00:29:41 Andrew Dunkley, thanks for your company.

00:29:42 --> 00:29:43 We'll see you on the next episode of Space

00:29:43 --> 00:29:44 Nuts.

00:29:44 --> 00:29:44 Andrew Dunkley: Bye.

00:29:44 --> 00:29:44 Generic: Bye.

00:29:46 --> 00:29:48 Andrew Dunkley: You've been listening to the Space Nuts

00:29:48 --> 00:29:51 podcast, mission completed. Available at

00:29:51 --> 00:29:53 Apple Podcasts, Spotify,

00:29:53 --> 00:29:56 iHeartRadio or your favourite podcast

00:29:56 --> 00:29:58 player. You can also stream on

00:29:58 --> 00:30:00 demand@bytes.com this

00:30:00 --> 00:30:02 Professor Fred Watson: has been another quality podcast production

00:30:02 --> 00:30:04 from bytes.com.