Join Andrew Dunkley and Professor Fred Watson as they explore the latest developments in space science—from evidence of complex organic molecules found by the Perseverance rover on Mars that may hint at past life, to the ongoing mystery of the Hubble tension that challenges our understanding of the universe's expansion. Plus, a deep dive into the elusive concept of dark photons and their potential role in explaining dark matter.
Key Topics:
The significance of complex carbon molecules detected in Martian rocks by Perseverance and their implications for extraterrestrial life
The challenges and prospects of returning samples from Mars and the influence of upcoming Chinese missions
Understanding the Hubble tension: different measurements of the universe's expansion rate and what they could mean for new physics
The role of gravitational wave observations in refining the Hubble constant and resolving cosmological discrepancies
An introduction to dark photons: what they are and their potential connection to dark matter and dark energy
The nature of cosmic redshift, light travel time, and how we look back in cosmic history
The possibility of the universe expanding into higher dimensions or higher-dimensional multiverses
The shape and boundaries of the universe: flat, spherical, or saddle-shaped?
Resources & Links:
Science Advances Paper on Martian Organic Molecules
NASA Perseverance Rover
Cosmological Parameters and Hubble Tension
Large Hadron Collider Official Site
Dark Photons and Dark Matter — University of California
BiteStop Streaming Service
Connect with Fred Watson:
Professor Fred Watson - LinkedIn
Professor Fred Watson - Twitter
Note:
Stay tuned for future episodes where we continue exploring mysteries of the cosmos, and don't forget to visit our website to send questions or feedback!
Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts-astronomy-insights-cosmic-discoveries--2631155/support.
00:00:00 --> 00:00:02 Andrew Dunkley: Hi there. Thanks for joining us. This is
00:00:02 --> 00:00:05 Space Nuts, where we talk astronomy and space
00:00:05 --> 00:00:08 science and sometimes puppy dogs. Who knows?
00:00:08 --> 00:00:10 Uh, my name is Andrew Dunkley, uh, your host.
00:00:10 --> 00:00:13 It's great to have your company. Coming up on
00:00:13 --> 00:00:16 this episode, we are going to look into
00:00:16 --> 00:00:19 a discovery made through the Perseverance
00:00:19 --> 00:00:21 Rover on Mars. Uh, have they
00:00:22 --> 00:00:24 found what could have been life in Mars's
00:00:24 --> 00:00:26 history? Or is it another rock that's just
00:00:26 --> 00:00:29 got a stain on it? Uh, also, uh, we've
00:00:29 --> 00:00:32 got some news on the Hubble Tension and the
00:00:32 --> 00:00:35 Large Hadron Collider is no
00:00:35 --> 00:00:37 more. Well, it's going to be more,
00:00:37 --> 00:00:40 but it needs to be no more to be more.
00:00:40 --> 00:00:42 We'll tell you all about it on this episode
00:00:42 --> 00:00:43 of space nuts.
00:00:44 --> 00:00:46 Professor Fred Watson: 15 seconds. Guidance is internal.
00:00:46 --> 00:00:49 10, 9. Ignition
00:00:49 --> 00:00:50 sequence start.
00:00:50 --> 00:00:51 Professor Fred Watson: Space nuts.
00:00:51 --> 00:00:54 Professor Fred Watson: 5, 4, 3, 2. 1, 2, 3, 4,
00:00:54 --> 00:00:56 5, 5, 4, 3, 2, 1.
00:00:56 --> 00:00:57 Andrew Dunkley: Space nuts.
00:00:57 --> 00:00:59 Professor Fred Watson: Astronauts report it feels good.
00:01:00 --> 00:01:03 Andrew Dunkley: Joining us again to discuss all of those
00:01:03 --> 00:01:04 things and more is Professor Fred Watson
00:01:04 --> 00:01:06 Watson, astronomer at large. Hi, Fred Watson.
00:01:07 --> 00:01:09 Professor Fred Watson: Hello, Andrew. Good to see you.
00:01:09 --> 00:01:10 Andrew Dunkley: Good to see you too.
00:01:10 --> 00:01:13 Professor Fred Watson: Good to be back on Space Nuts. It
00:01:13 --> 00:01:14 is, it is.
00:01:14 --> 00:01:14 Andrew Dunkley: It's very good.
00:01:15 --> 00:01:17 Uh, we've got a lot to talk about, so we
00:01:17 --> 00:01:20 might as well dive right in because, um,
00:01:20 --> 00:01:22 it wasn't so long ago that we had a bit of a
00:01:22 --> 00:01:25 chat about a, A rock that they
00:01:25 --> 00:01:27 found that they said came from Mars and it
00:01:27 --> 00:01:29 showed, uh, there was life. And then it
00:01:29 --> 00:01:32 turned out to be nothing like that.
00:01:33 --> 00:01:35 Uh, and now we have a storey popping up.
00:01:36 --> 00:01:38 Uh, that suggests the Perseverance Rover may
00:01:38 --> 00:01:41 have detected complex carbon,
00:01:41 --> 00:01:44 uh, molecules in Martian rocks that
00:01:44 --> 00:01:47 may have been signatures for
00:01:47 --> 00:01:50 life. Um, yeah, you can't, uh,
00:01:50 --> 00:01:52 you can't say, look, I found formal life on
00:01:52 --> 00:01:54 Mars. It's all over. Red Rover. Boom, boom.
00:01:54 --> 00:01:56 That's a good joke, that. Think about it.
00:01:57 --> 00:02:00 Professor Fred Watson: And, um, I didn't need to think too
00:02:00 --> 00:02:00 hard.
00:02:01 --> 00:02:04 Andrew Dunkley: And, uh, look, you've just got to take
00:02:04 --> 00:02:07 this with a grain of, uh, Martian salt and
00:02:07 --> 00:02:09 hope that that's what they've actually found.
00:02:09 --> 00:02:10 That's what it's all about.
00:02:12 --> 00:02:15 Professor Fred Watson: You have to go back to that pink planet we
00:02:15 --> 00:02:17 were talking about a few episodes ago to get
00:02:17 --> 00:02:18 the grain of salt to.
00:02:18 --> 00:02:19 Andrew Dunkley: Pink Salt planet,
00:02:21 --> 00:02:22 Professor Fred Watson: indeed.
00:02:22 --> 00:02:25 So, um, yes, the storey is. It is, um,
00:02:25 --> 00:02:27 as you've hinted, um, a kind of
00:02:27 --> 00:02:30 extension of a storey that we covered a few
00:02:30 --> 00:02:33 weeks ago, which was this particular
00:02:33 --> 00:02:36 rock, um, which
00:02:36 --> 00:02:38 is, uh, from an outcrop called
00:02:38 --> 00:02:41 the Bright Angel Outcrop, uh, on, um,
00:02:42 --> 00:02:45 Mars. Uh, so this is the Perseverance Rover,
00:02:45 --> 00:02:47 which you'll Remember is working hard in
00:02:47 --> 00:02:50 Jezero Crater, where there is a
00:02:50 --> 00:02:53 river Delta from probably 3.5 billion
00:02:53 --> 00:02:55 years ago. So, um, the Bright
00:02:55 --> 00:02:58 angel outcrop and the particular rock
00:02:59 --> 00:03:01 that they found, um, I can't see whether
00:03:02 --> 00:03:04 it had a particular name, but it was a
00:03:04 --> 00:03:07 mudstone rock which had,
00:03:08 --> 00:03:11 uh, basically, as you said, stains on them.
00:03:12 --> 00:03:15 Uh, stains on the surface. Um, stains on
00:03:15 --> 00:03:16 Mars will be interesting because you'd wonder
00:03:16 --> 00:03:19 where they came from. But it's got
00:03:19 --> 00:03:21 surface spots and what have been called
00:03:21 --> 00:03:24 nodules. Uh, and the
00:03:24 --> 00:03:27 reason why it caused excitement was
00:03:27 --> 00:03:30 that some of those features superficially
00:03:30 --> 00:03:33 resemble the features that are
00:03:33 --> 00:03:36 produced on Earth by fossilised
00:03:36 --> 00:03:37 microbes. And that's what we covered
00:03:37 --> 00:03:40 actually, back in 2024. It seems like only
00:03:40 --> 00:03:42 yesterday, but we did talk about that.
00:03:43 --> 00:03:45 Or maybe. No, it was probably last year
00:03:45 --> 00:03:47 actually. Um, I think that's when the results
00:03:47 --> 00:03:49 came out. So last year, 2025.
00:03:50 --> 00:03:53 Uh, uh, and a quote, um,
00:03:54 --> 00:03:56 uh, there's a nice Guardian piece on this
00:03:56 --> 00:03:59 Storey, but there's a quote from Sean Duffy,
00:03:59 --> 00:04:01 who used to acting head of NASA,
00:04:01 --> 00:04:04 uh, who said of that discovery, this
00:04:04 --> 00:04:07 very well could be the clearest sign of life
00:04:07 --> 00:04:09 that we've ever found on Mars. Which is
00:04:10 --> 00:04:12 an interesting comment. And of course
00:04:12 --> 00:04:15 all astrobiologists and all scientists
00:04:15 --> 00:04:17 probably, and all, um, podcast presenters,
00:04:17 --> 00:04:20 uh, couch this sort of discovery in very,
00:04:20 --> 00:04:23 very, um, broad terms
00:04:23 --> 00:04:26 because, uh, with. There's
00:04:26 --> 00:04:29 certainly no. This is certainly not a
00:04:29 --> 00:04:32 definitive discovery of life
00:04:32 --> 00:04:35 on Mars, but it
00:04:35 --> 00:04:38 has basically gone
00:04:38 --> 00:04:40 further in the sense that the samples
00:04:41 --> 00:04:44 that, uh, Perseverance took
00:04:44 --> 00:04:47 from this mudstone, uh,
00:04:47 --> 00:04:49 showed that there was something called
00:04:49 --> 00:04:52 macromolecular carbon on its surface.
00:04:53 --> 00:04:56 And that's something. A
00:04:56 --> 00:04:58 carbon, you know, it's carbon compounds,
00:04:59 --> 00:05:01 probably. Excuse me. Sorry about that,
00:05:01 --> 00:05:03 Andrew, just bellowing into my microphone
00:05:03 --> 00:05:05 here. I do apologise. Um,
00:05:06 --> 00:05:09 um. Uh, it's probably several
00:05:09 --> 00:05:12 organic types of organic
00:05:12 --> 00:05:13 molecule and of course organic means
00:05:13 --> 00:05:16 containing carbon associated with life
00:05:16 --> 00:05:18 normally. Um, but, uh, the
00:05:18 --> 00:05:21 analysis of this shows,
00:05:21 --> 00:05:23 and the analysis by Perseverance
00:05:24 --> 00:05:27 shows that it is, uh,
00:05:27 --> 00:05:30 a possibility that
00:05:31 --> 00:05:34 this life, these organic, these
00:05:34 --> 00:05:37 macromolecules, carbon macromolecules,
00:05:37 --> 00:05:39 could have been the result of life
00:05:39 --> 00:05:42 processes, but they could also
00:05:43 --> 00:05:45 come from basically,
00:05:46 --> 00:05:49 uh, I mean essentially, um, geological
00:05:49 --> 00:05:51 processes, tectonic processes. And
00:05:51 --> 00:05:54 so that's where the
00:05:54 --> 00:05:57 thing stands at the moment. Uh,
00:05:58 --> 00:05:59 we know from,
00:06:01 --> 00:06:04 uh, work that's already been done by
00:06:04 --> 00:06:06 the Perseverance rover and Perseverance,
00:06:07 --> 00:06:10 uh, so Curiosity went to Mars to
00:06:10 --> 00:06:12 determine whether Mars was ever habitable.
00:06:12 --> 00:06:15 And we know that from Curiosity it found that
00:06:15 --> 00:06:17 out within the first two weeks of being
00:06:17 --> 00:06:20 there. Um, but we know now from
00:06:20 --> 00:06:23 perseverance that Jezero Crater was also
00:06:23 --> 00:06:25 a habitable, habitable environment
00:06:26 --> 00:06:29 at um, least for some sort of primitive level
00:06:29 --> 00:06:32 of life. Um, but of course uh, the
00:06:32 --> 00:06:34 issue is that we won't be able to do the
00:06:34 --> 00:06:37 proper tests on these samples until
00:06:37 --> 00:06:40 we get these samples back to Earth, uh,
00:06:40 --> 00:06:43 laboratories where there's far more refined
00:06:43 --> 00:06:45 equipment than you can carry on a little
00:06:45 --> 00:06:47 rover on Mars. And the problem is we
00:06:47 --> 00:06:49 don't currently have any way of doing that,
00:06:49 --> 00:06:52 of getting these samples back because the um,
00:06:53 --> 00:06:55 the mission uh, to do that, a uh,
00:06:55 --> 00:06:58 joint NASA European Space Agency mission
00:06:59 --> 00:07:01 fell foul of politics in the United States
00:07:01 --> 00:07:03 and was cancelled earlier in the year.
00:07:03 --> 00:07:04 Professor Fred Watson: Uh,
00:07:05 --> 00:07:07 Professor Fred Watson: we knew it was in trouble anyway because the
00:07:07 --> 00:07:10 cost had sort of blown out. So it's not a
00:07:10 --> 00:07:11 surprise that that happened. But at the
00:07:11 --> 00:07:14 moment there's nothing on the books to get
00:07:14 --> 00:07:17 them back. Few plans going on I think,
00:07:17 --> 00:07:19 but not to get them back.
00:07:20 --> 00:07:23 Andrew Dunkley: Yeah, and that's uh, frustrating but I
00:07:23 --> 00:07:25 suppose in the scheme of things it's, I mean
00:07:25 --> 00:07:28 we all want to know whether or not Mars
00:07:28 --> 00:07:31 had life but it's probably not one of the
00:07:31 --> 00:07:33 most urgent things to deal with. Um,
00:07:34 --> 00:07:36 we'll get around to it and chances
00:07:36 --> 00:07:39 are that those um,
00:07:40 --> 00:07:42 cylinders I think they are, that the deposits
00:07:42 --> 00:07:45 are in will be collected as a part of
00:07:45 --> 00:07:48 another major mission. That would be my
00:07:48 --> 00:07:49 thinking sometime in the future.
00:07:50 --> 00:07:53 Professor Fred Watson: You're probably right. Uh, although it's
00:07:53 --> 00:07:56 a very specific type of mission that's going
00:07:56 --> 00:07:57 to go and collect these samples
00:07:59 --> 00:08:01 and then send them back to Earth. That's the
00:08:01 --> 00:08:04 tricky bit. It is, it's
00:08:04 --> 00:08:06 probably a two step process where you've got
00:08:06 --> 00:08:09 an orbiter um, sent to
00:08:09 --> 00:08:11 Mars, goes into orbit around Mars, that drops
00:08:11 --> 00:08:14 a probe onto the surface. The probe picks up
00:08:14 --> 00:08:17 the uh, cache samples,
00:08:17 --> 00:08:20 not ah, cash but
00:08:20 --> 00:08:23 cache, uh, and um, brings them
00:08:23 --> 00:08:25 back up to the orbiter and then the orbiter
00:08:25 --> 00:08:28 sends off a probe to the Earth and that re
00:08:28 --> 00:08:30 enters. It's a very complex process which is
00:08:30 --> 00:08:33 why the cost blew out. But um, I
00:08:33 --> 00:08:36 do have my own view on what might prompt
00:08:36 --> 00:08:39 uh, some urgency with this and that is that
00:08:39 --> 00:08:42 the Chinese are planning to do a sample
00:08:42 --> 00:08:44 return mission to Mars uh, in
00:08:44 --> 00:08:47 the2030s. So um,
00:08:47 --> 00:08:50 if anything's going to stimulate some action
00:08:50 --> 00:08:53 on this, my guess is that that's what it
00:08:53 --> 00:08:56 would be. And you know, all praise to
00:08:56 --> 00:08:57 the China National Space Agency.
00:08:57 --> 00:08:58 Professor Fred Watson: Absolutely.
00:08:58 --> 00:09:01 Professor Fred Watson: Uh, for aiming high. It's a great thing to
00:09:01 --> 00:09:01 do.
00:09:01 --> 00:09:02 Andrew Dunkley: It is.
00:09:02 --> 00:09:05 And um, the other interesting thing
00:09:05 --> 00:09:07 I suppose and you mentioned Curiosity. Uh,
00:09:08 --> 00:09:10 it's starting to build up evidence
00:09:10 --> 00:09:13 that, um, the potential for life
00:09:13 --> 00:09:16 on Mars was widespread across the
00:09:16 --> 00:09:17 planet.
00:09:17 --> 00:09:20 Professor Fred Watson: Yes, correct. That's right. So I meant
00:09:20 --> 00:09:21 to mention that. That's absolutely right.
00:09:21 --> 00:09:23 That you know, when you've got, um,
00:09:24 --> 00:09:27 uh, mudstones separated by 3
00:09:27 --> 00:09:30 kilometres or thereabouts, uh, and
00:09:30 --> 00:09:33 giving you the same sort of answer. Yeah,
00:09:33 --> 00:09:34 that I think is, um,
00:09:35 --> 00:09:38 it's a very, very strong evidence
00:09:38 --> 00:09:41 for there having been the possibility of life
00:09:41 --> 00:09:44 on Mars and that it might be findable, if I
00:09:44 --> 00:09:46 can put it that way, if the conditions are
00:09:46 --> 00:09:49 suitable for life everywhere, then there
00:09:49 --> 00:09:52 might be remnants, um, of living
00:09:52 --> 00:09:54 organisms everywhere on Mars which we have,
00:09:54 --> 00:09:56 uh, a good chance of finding. Because
00:09:57 --> 00:10:00 when NASA and other space agencies
00:10:00 --> 00:10:03 aim to send, uh, spacecraft to Mars,
00:10:03 --> 00:10:06 it's not quite just a tail on
00:10:06 --> 00:10:08 the donkey thing where you just poke it in
00:10:08 --> 00:10:11 willy nilly. You've got really good reasons
00:10:11 --> 00:10:13 for going to any specific place. And
00:10:13 --> 00:10:15 certainly Jezero Crater, um, it
00:10:15 --> 00:10:18 was a masterstroke. Sending it to a lake
00:10:18 --> 00:10:20 that, uh, had, um, a
00:10:20 --> 00:10:21 river delta in it.
00:10:22 --> 00:10:24 Andrew Dunkley: Yeah, they, they picked a good target. Uh,
00:10:24 --> 00:10:27 that was intentional. And yes, uh, it seems
00:10:27 --> 00:10:29 to be paying off. Fingers. Fingers crossed.
00:10:29 --> 00:10:32 But, um, yeah, too early to tell. But looking
00:10:32 --> 00:10:35 somewhat promising is, I think, the best way
00:10:35 --> 00:10:36 to describe it at the moment.
00:10:36 --> 00:10:39 Professor Fred Watson: That's right. It's not, it's not a kind of
00:10:39 --> 00:10:40 negative result. It's not saying, oh, no,
00:10:40 --> 00:10:43 there's no life on Mars. It's saying, hm,
00:10:43 --> 00:10:44 there might be. It might have been.
00:10:44 --> 00:10:47 Andrew Dunkley: Might, might have been. And still might be.
00:10:47 --> 00:10:49 Professor Fred Watson: It still might be. That's right, yeah.
00:10:50 --> 00:10:52 Andrew Dunkley: You can read all about that@theguardian.com
00:10:52 --> 00:10:55 or you can read the paper that's been
00:10:55 --> 00:10:58 published in Science Advances. This is Space
00:10:58 --> 00:11:00 Nuts with Andrew Dunkley and Professor
00:11:00 --> 00:11:00 Fred Watson Watson.
00:11:03 --> 00:11:04 Space Nuts.
00:11:04 --> 00:11:06 Now, uh, one of our, um, semi
00:11:06 --> 00:11:09 regular topics is the Hubble
00:11:09 --> 00:11:12 Tension and it's back in the news again,
00:11:12 --> 00:11:15 uh, because of a, um,
00:11:15 --> 00:11:18 another detection involving the collision
00:11:18 --> 00:11:20 of neutron stars. Is that right?
00:11:20 --> 00:11:23 Professor Fred Watson: That's correct, yes. Um, yes.
00:11:23 --> 00:11:26 So, uh, the Hubble Tension is one
00:11:26 --> 00:11:29 of these irritating things that just won't
00:11:29 --> 00:11:30 go away.
00:11:31 --> 00:11:33 Andrew Dunkley: Well, it's being described as one of the
00:11:33 --> 00:11:35 biggest challenges in modern cosmology. So,
00:11:35 --> 00:11:36 yes, it won't go away.
00:11:36 --> 00:11:39 Professor Fred Watson: It won't go away. But it's a bit weird. I
00:11:39 --> 00:11:42 did a radio segment about it, um, with a
00:11:43 --> 00:11:45 Australian commercial radio station yesterday
00:11:45 --> 00:11:48 morning because of the headline storey. Uh,
00:11:48 --> 00:11:51 and I thought, how do you make this exciting?
00:11:53 --> 00:11:55 It was, first thing you know, it was a
00:11:55 --> 00:11:57 morning breakfast show and the guys who Were
00:11:57 --> 00:11:59 interviewing me, were clearly not impressed
00:11:59 --> 00:12:02 with it. Uh, normally I get lots of questions
00:12:02 --> 00:12:05 Andrew Dunkley: from them, but, um, it may well have just
00:12:05 --> 00:12:08 been something that goes
00:12:08 --> 00:12:11 into the too hard basket because it's not an
00:12:11 --> 00:12:12 easy thing to get your head around.
00:12:12 --> 00:12:15 Professor Fred Watson: It's not. That's right. It's not. Um,
00:12:15 --> 00:12:17 there's a lot of gobbledygook attached to it.
00:12:17 --> 00:12:19 Anyway, let's have a go. We have a very
00:12:19 --> 00:12:21 erudite audience on Space Nuts. Uh,
00:12:22 --> 00:12:24 and Space Nuts, uh, listeners
00:12:25 --> 00:12:27 will probably already be aware of all this
00:12:27 --> 00:12:30 anyway. Um, but, uh. Yes.
00:12:30 --> 00:12:33 So what's the Hubble tension? Uh, we have
00:12:33 --> 00:12:36 two measurements of the Hubble constant,
00:12:36 --> 00:12:38 which is the number that defines how fast
00:12:38 --> 00:12:41 the universe is expanding. Now,
00:12:42 --> 00:12:45 it's the expansion time or the
00:12:45 --> 00:12:48 expansion rate that we are seeing. Uh, as
00:12:48 --> 00:12:50 you and I have said many times before, it's
00:12:50 --> 00:12:52 measured in units of kilometres per second
00:12:52 --> 00:12:54 per megaparsec. Uh, and A
00:12:54 --> 00:12:57 megaparsec is 3.26 million light
00:12:57 --> 00:12:59 years. It's the units astronomers use because
00:12:59 --> 00:13:01 you can't measure light years, but you can
00:13:01 --> 00:13:03 measure parsecs. So, um,
00:13:04 --> 00:13:06 that number is, uh,
00:13:06 --> 00:13:09 the magic number. And we have,
00:13:11 --> 00:13:13 uh, two different ways of determining it,
00:13:13 --> 00:13:16 both of which now have achieved a really
00:13:16 --> 00:13:18 high level of precision. Um,
00:13:19 --> 00:13:22 there was a talk that I was at a couple of
00:13:22 --> 00:13:24 months ago in Germany where, uh, one of the
00:13:24 --> 00:13:27 experts was talking about this, uh, and
00:13:28 --> 00:13:30 the sort of uncertainty limits that are put
00:13:30 --> 00:13:33 on each of these two different methods of
00:13:33 --> 00:13:35 determining the Hubble constant. They were
00:13:35 --> 00:13:38 very small, uh, on the order of one
00:13:38 --> 00:13:40 kilometre per second. Very, very, uh,
00:13:40 --> 00:13:43 accurate measurements. Uh, but they
00:13:43 --> 00:13:46 disagree. So, uh, you can do it two ways.
00:13:46 --> 00:13:48 The first way is to
00:13:49 --> 00:13:52 look at the cosmic microwave background
00:13:52 --> 00:13:55 radiation, the good, uh, old background glow
00:13:55 --> 00:13:57 of the Big Bang that is everywhere in the
00:13:57 --> 00:13:59 sky. Uh, it has,
00:14:00 --> 00:14:02 um, undulations on it in temperature, uh,
00:14:02 --> 00:14:05 which we recognise as being
00:14:05 --> 00:14:07 differences in the temperature of the Big
00:14:07 --> 00:14:10 Bang fireball,
00:14:10 --> 00:14:12 uh, which are caused by acoustic
00:14:12 --> 00:14:14 oscillations. It's the bang of the Big Bang.
00:14:15 --> 00:14:17 But you can use those undulations to get a
00:14:17 --> 00:14:20 measurement of the Hubble constant. And the
00:14:20 --> 00:14:23 value that that technology gets or that
00:14:23 --> 00:14:26 method gets is 67 to 68 kilometres per
00:14:26 --> 00:14:29 second per megaparsec. The
00:14:29 --> 00:14:32 other way of, uh, measuring this
00:14:32 --> 00:14:34 is to look in the nearby universe. You look
00:14:34 --> 00:14:37 at galaxies whose distances are measured in,
00:14:37 --> 00:14:40 um, millions or hundreds of millions of light
00:14:40 --> 00:14:43 years. Uh, and that's very local compared
00:14:43 --> 00:14:45 with the 13.8 billion light years
00:14:45 --> 00:14:48 of the cosmic microwave background. Um,
00:14:48 --> 00:14:51 so you look locally and you look for the
00:14:51 --> 00:14:53 traditional methods of Finding, um,
00:14:54 --> 00:14:57 uh, the distances to galaxies, uh, which,
00:14:57 --> 00:14:59 uh, one of them is by what we call
00:14:59 --> 00:15:02 Cepheid variable stars. That was the way that
00:15:02 --> 00:15:04 galaxies were first established to be a long
00:15:04 --> 00:15:07 way off in 1923. Um, you
00:15:07 --> 00:15:09 can also do it with supernova explosions, all
00:15:09 --> 00:15:12 of that sort of stuff, uh, gives you another
00:15:12 --> 00:15:15 alternative value, uh, on the Hubble
00:15:15 --> 00:15:18 constant, and that gives you a higher answer.
00:15:18 --> 00:15:21 So the local universe gives
00:15:21 --> 00:15:24 you, uh, uh, an answer of about
00:15:24 --> 00:15:26 73 kilometres per second per
00:15:26 --> 00:15:29 megaparsec, sort of. So that's
00:15:29 --> 00:15:32 roughly 5. Higher. 5
00:15:32 --> 00:15:35 kilometres per second per megaparsec higher
00:15:35 --> 00:15:36 than the one you get from the Hubble
00:15:36 --> 00:15:39 constant. Now that's, you know, I suppose
00:15:39 --> 00:15:41 that's, uh, something like a 6 or
00:15:41 --> 00:15:44 7% difference between them. And
00:15:44 --> 00:15:47 I can tell you, 30 years ago, um, when I
00:15:47 --> 00:15:50 was an astronomer, kind of a
00:15:50 --> 00:15:53 bit more directly connected with all this 5%.
00:15:54 --> 00:15:57 We'd die for 5%. That was, um,
00:15:58 --> 00:16:00 6 or 7% or whatever the difference is 5
00:16:00 --> 00:16:02 kilometres per second per megaparsec, uh,
00:16:02 --> 00:16:04 because most of them differed by 50
00:16:04 --> 00:16:06 kilometres per second per megaparsec back
00:16:06 --> 00:16:09 then. Um, so, uh, and it was the Hubble
00:16:09 --> 00:16:11 telescope that actually nailed it down to be
00:16:11 --> 00:16:14 in the region of 70. But, yes, we have this
00:16:14 --> 00:16:17 discrepancy. Uh, um. What's the
00:16:17 --> 00:16:19 answer? So, um.
00:16:20 --> 00:16:21 Actually, I might just quote there's a very
00:16:21 --> 00:16:23 nice conversation piece by one of the
00:16:23 --> 00:16:26 astronomers involved, um, with this, who
00:16:26 --> 00:16:29 is a radio astronomer at csiro, the
00:16:29 --> 00:16:31 Australia's National Science Agency.
00:16:32 --> 00:16:35 Uh, Kelly Gurgi. Uh, and, uh,
00:16:35 --> 00:16:37 let me see if I can find this comment. Yes,
00:16:38 --> 00:16:41 that's that. So that Kelly says this is the
00:16:41 --> 00:16:43 Hubble tension. What does it mean? Could it
00:16:43 --> 00:16:45 be something. Could it be something has gone
00:16:45 --> 00:16:48 awry in one or both methods?
00:16:48 --> 00:16:51 Despite intense scrutiny, nobody has found
00:16:51 --> 00:16:54 any mistakes. Alternatively, our
00:16:54 --> 00:16:56 understanding of how the universe evolves may
00:16:56 --> 00:16:58 be missing something fundamental and we need
00:16:58 --> 00:16:59 new physics to resolve it.
00:17:00 --> 00:17:00 Professor Fred Watson: Uh,
00:17:02 --> 00:17:05 Professor Fred Watson: to settle this cosmic M debate, new and
00:17:05 --> 00:17:07 independent methods of measuring the Hubble
00:17:07 --> 00:17:09 constant are, uh, highly sought after.
00:17:09 --> 00:17:12 Which gets us to the storey. Yes, yes.
00:17:13 --> 00:17:14 Andrew Dunkley: We had to fill in all the blanks.
00:17:14 --> 00:17:17 Professor Fred Watson: That's right. Um,
00:17:17 --> 00:17:20 and as the article goes on, gravitational
00:17:20 --> 00:17:22 waves offer an entirely independent way to
00:17:22 --> 00:17:25 measure the expansion of the universe. And we
00:17:25 --> 00:17:26 know about gravitational waves. That's very
00:17:26 --> 00:17:29 much the stock in trade of what we talk about
00:17:29 --> 00:17:32 on Space Nuts. Uh, and
00:17:32 --> 00:17:34 so, uh, what they've done is gone back to one
00:17:34 --> 00:17:37 that was particularly interesting. Uh,
00:17:37 --> 00:17:40 and as you know, gravitational waves get
00:17:40 --> 00:17:42 their number from the date when they're
00:17:42 --> 00:17:43 discovered. This was
00:17:43 --> 00:17:46 GW170817.
00:17:47 --> 00:17:49 So, discovered on the 17th of August, uh,
00:17:49 --> 00:17:51 2017. Um,
00:17:52 --> 00:17:55 that's only two years after the first one was
00:17:55 --> 00:17:56 found. Actually, I think it's only a year
00:17:56 --> 00:17:59 after. I think, uh, it's two years, certainly
00:17:59 --> 00:18:01 two years after the first one was observed.
00:18:02 --> 00:18:04 Um, so, uh,
00:18:05 --> 00:18:08 and this was a neutron star collision, two
00:18:08 --> 00:18:11 neutron stars. And that has the
00:18:11 --> 00:18:13 property unlike a black hole neutron star
00:18:13 --> 00:18:15 collision or a black hole black hole
00:18:15 --> 00:18:18 collision. A neutron star neutron star
00:18:18 --> 00:18:20 collision, uh, actually produces
00:18:20 --> 00:18:23 radiation, electromagnetic radiation. It
00:18:23 --> 00:18:25 produces a flash or a glow.
00:18:26 --> 00:18:28 Um, and that is something you can
00:18:28 --> 00:18:31 detect. So for a start, that means you know
00:18:31 --> 00:18:33 where these gravitational waves have come
00:18:33 --> 00:18:35 from. With a high level of certainty. You can
00:18:35 --> 00:18:38 take test all kinds of things like the fact
00:18:38 --> 00:18:40 that gravitational waves, uh, travel at the
00:18:40 --> 00:18:43 speed of light. All of that sort of pops out
00:18:43 --> 00:18:45 of GW, uh,
00:18:45 --> 00:18:48 17 08, uh, 1 7. Uh,
00:18:48 --> 00:18:50 so it was a remarkable event.
00:18:51 --> 00:18:54 Uh, what has now happened though is
00:18:54 --> 00:18:56 that people have used the analysis of that
00:18:56 --> 00:18:59 signal to sort of tease out,
00:18:59 --> 00:19:02 um, the information about the
00:19:02 --> 00:19:05 Hubble constant. And they get an answer
00:19:06 --> 00:19:08 that is not as accurate as either of the
00:19:08 --> 00:19:10 other ones because they haven't got that
00:19:10 --> 00:19:13 precision yet for this method. But it's
00:19:13 --> 00:19:15 intriguingly like the,
00:19:15 --> 00:19:18 uh, measurement from the
00:19:18 --> 00:19:21 distant universe. Uh, that is the
00:19:21 --> 00:19:24 higher, uh, um, the lower
00:19:24 --> 00:19:27 value. Uh, that's the. Remember, the
00:19:27 --> 00:19:30 distant universe measurements have about 67
00:19:30 --> 00:19:32 to 68 kilometres per second per megaparsec.
00:19:32 --> 00:19:35 The other one was more like 73. Um, this
00:19:35 --> 00:19:37 new value is somewhere between
00:19:37 --> 00:19:40 61 and 70 kilometres per
00:19:40 --> 00:19:42 second per megaparsec, which kind of
00:19:43 --> 00:19:46 is outside the range of the near
00:19:46 --> 00:19:49 universe value. Uh,
00:19:49 --> 00:19:52 uh, um, so it agrees much more
00:19:52 --> 00:19:54 with the distant universe value.
00:19:55 --> 00:19:56 Even though
00:19:57 --> 00:20:00 GW170817
00:20:01 --> 00:20:04 came from a galaxy that is
00:20:04 --> 00:20:07 not that far away in cosmic terms,
00:20:07 --> 00:20:09 it's about 140 million light years from
00:20:09 --> 00:20:12 Earth and that's sort of on our doorstep in
00:20:12 --> 00:20:15 galactic terms. So here you've got an
00:20:15 --> 00:20:16 independent method,
00:20:18 --> 00:20:20 uh, that gives an answer more like the
00:20:20 --> 00:20:23 distant method did. Uh, but it's
00:20:23 --> 00:20:26 using, uh, nearby objects rather than
00:20:26 --> 00:20:28 distant objects. So I think what it's done
00:20:29 --> 00:20:31 is very neatly thrown the cat among the
00:20:31 --> 00:20:32 pigeons again.
00:20:32 --> 00:20:33 Andrew Dunkley: Sure has.
00:20:34 --> 00:20:36 Professor Fred Watson: Um, well, let me just read
00:20:36 --> 00:20:39 the article. Uh, the last paragraph is our
00:20:39 --> 00:20:42 result is still four times less precise than
00:20:42 --> 00:20:44 the leading nearby universe measurements. We
00:20:44 --> 00:20:45 will need to detect more neutron star
00:20:45 --> 00:20:47 collisions to definitively settle the Hubble
00:20:47 --> 00:20:50 tension using gravitational waves. Such
00:20:50 --> 00:20:52 events are rare, so it may be a while. But
00:20:52 --> 00:20:55 for now, our study provides an important new
00:20:55 --> 00:20:57 clue in one of Astronomy's biggest problems.
00:20:58 --> 00:20:59 And that's where they leave it.
00:21:00 --> 00:21:03 Andrew Dunkley: Where does that place the
00:21:03 --> 00:21:05 storey? We did a couple of years ago about,
00:21:05 --> 00:21:08 ah, a study into the Hubble tension,
00:21:08 --> 00:21:11 um, trying to understand the differentiation
00:21:11 --> 00:21:13 between the two existing methods where they
00:21:13 --> 00:21:15 said, look, the difference is not that big a
00:21:15 --> 00:21:17 deal. They're both right. So
00:21:18 --> 00:21:19 where does that stand now? Do you remember
00:21:19 --> 00:21:20 talking about that?
00:21:20 --> 00:21:22 Professor Fred Watson: Yeah, I do remember. Yeah, we've covered it,
00:21:22 --> 00:21:24 certainly covered it before. Um,
00:21:25 --> 00:21:27 so if that's the case, if they're both right,
00:21:27 --> 00:21:29 and I think that was the outcome of that,
00:21:29 --> 00:21:31 then that's pushing you towards new physics
00:21:31 --> 00:21:33 because, um,
00:21:36 --> 00:21:38 to get two different results
00:21:39 --> 00:21:41 for the same thing by two different
00:21:42 --> 00:21:44 methods, both of which use general
00:21:44 --> 00:21:47 relativity as their basis, that is the firm
00:21:47 --> 00:21:49 basis of our understanding of the universe.
00:21:50 --> 00:21:52 Uh, what that suggests is there's something
00:21:52 --> 00:21:55 wrong with general relativity. Now we've
00:21:55 --> 00:21:57 believed that for a long time, but so far,
00:21:57 --> 00:22:00 all the tests, it comes out on top. It comes
00:22:00 --> 00:22:03 out with these incredible, uh,
00:22:03 --> 00:22:05 incredibly precise accuracy in
00:22:05 --> 00:22:08 describing the way the universe works.
00:22:09 --> 00:22:11 Andrew Dunkley: All right, um, watch this space, I suppose.
00:22:12 --> 00:22:12 Professor Fred Watson: Yeah.
00:22:12 --> 00:22:15 Andrew Dunkley: Where we're at on that. More to come. It's
00:22:15 --> 00:22:18 um, one of those issues that just won't go
00:22:18 --> 00:22:21 away because, uh, well, being human beings we
00:22:21 --> 00:22:23 want to figure everything out so they won't
00:22:23 --> 00:22:26 give up on this. Uh, you can read about
00:22:26 --> 00:22:28 it at the Conversation website or you can
00:22:28 --> 00:22:30 read the paper which was published in the
00:22:30 --> 00:22:33 Astrophysical Journal. This is Space
00:22:33 --> 00:22:35 Nuts. Andrew Dunkley with Professor
00:22:35 --> 00:22:36 Fred Watson Watson.
00:22:38 --> 00:22:40 Professor Fred Watson: I believe that this nation should commit
00:22:40 --> 00:22:42 itself to achieving the goal
00:22:43 --> 00:22:46 before this decade is out of landing a
00:22:46 --> 00:22:48 man on the moon and returning him safely to
00:22:48 --> 00:22:49 the Earth.
00:22:49 --> 00:22:50 Andrew Dunkley: Face nuts.
00:22:51 --> 00:22:53 Now we got a question about the Large
00:22:53 --> 00:22:56 Hadron Collider. Recently they were asking
00:22:56 --> 00:22:59 about the, the speed of two particles hitting
00:22:59 --> 00:23:00 each other at the speed of light. Would that
00:23:00 --> 00:23:02 be twice the speed of light? And the answer
00:23:02 --> 00:23:05 was no. But the Large
00:23:05 --> 00:23:08 Hadron Collider is in the news for a
00:23:08 --> 00:23:11 different, uh, a different reason. They're
00:23:11 --> 00:23:12 shutting it down. It's bye bye
00:23:13 --> 00:23:16 Large Hadron Collider. But not forever. In
00:23:16 --> 00:23:19 fact, um, they're going to do some
00:23:19 --> 00:23:20 renovations. They're going to put a cubby
00:23:20 --> 00:23:23 house on top of it and a kid's playground.
00:23:23 --> 00:23:24 Professor Fred Watson: Grummy flower.
00:23:24 --> 00:23:26 Andrew Dunkley: Little coffee shop next next door.
00:23:29 --> 00:23:30 Professor Fred Watson: It's already got the coffee shop.
00:23:30 --> 00:23:32 Andrew Dunkley: Already got the coffee shop.
00:23:32 --> 00:23:32 Professor Fred Watson: Okay.
00:23:32 --> 00:23:34 Andrew Dunkley: They're going to do a bigger coffee shop.
00:23:34 --> 00:23:36 That's, that's really what this storey is
00:23:36 --> 00:23:36 about.
00:23:37 --> 00:23:39 Professor Fred Watson: Yeah. And the great thing from my point of
00:23:39 --> 00:23:42 view is that uh, in, uh, let
00:23:42 --> 00:23:45 me see, in Just over three weeks. I'll be
00:23:45 --> 00:23:48 there. Wow. Uh, so, yeah, so I
00:23:48 --> 00:23:48 love, I
00:23:48 --> 00:23:50 Andrew Dunkley: love the line in this storey on
00:23:50 --> 00:23:52 theuniversetoday.com. uh, see you later.
00:23:52 --> 00:23:55 Accelerator. Yes, I
00:23:55 --> 00:23:56 think that's very clever.
00:23:57 --> 00:23:58 Professor Fred Watson: It's a nice way to.
00:23:58 --> 00:23:59 Andrew Dunkley: I wish I'd thought of it.
00:23:59 --> 00:24:02 Professor Fred Watson: Yeah, I do too. Um, yeah, actually,
00:24:02 --> 00:24:04 you've always got to be careful, especially
00:24:04 --> 00:24:06 when you write about this machine, because
00:24:06 --> 00:24:08 Marnie, in one of our earlier tours, when we
00:24:08 --> 00:24:10 visited the Large Hadron Collider,
00:24:11 --> 00:24:13 had a spelling mistake in the word
00:24:13 --> 00:24:16 hadron, uh, which you probably don't need to
00:24:16 --> 00:24:19 think too hard about to work out what it was.
00:24:19 --> 00:24:21 But somebody had to point it out.
00:24:22 --> 00:24:23 Is that what really meant
00:24:26 --> 00:24:28 Andrew Dunkley: Transpose two letters?
00:24:28 --> 00:24:30 Professor Fred Watson: Yes. You transposed two letters.
00:24:30 --> 00:24:30 Andrew Dunkley: Yeah.
00:24:32 --> 00:24:34 Professor Fred Watson: Uh, it would have got some laughs. I think it
00:24:34 --> 00:24:37 did. Yes, I think it did. I'm sure it's
00:24:37 --> 00:24:39 happened before, but, um, Marnie never made
00:24:39 --> 00:24:41 that mistake again. But, yes, we're going
00:24:41 --> 00:24:43 again. And the fact that it switched off
00:24:44 --> 00:24:47 actually makes us hope that we might, uh,
00:24:47 --> 00:24:49 once again get a trip down into,
00:24:49 --> 00:24:52 uh, the tunnel where the accelerator is,
00:24:52 --> 00:24:55 that 27 kilometre long circle of
00:24:55 --> 00:24:58 pipe work, uh, where the subatomic particles
00:24:58 --> 00:25:00 are accelerated, but also perhaps into one of
00:25:00 --> 00:25:03 the experimental, uh, caverns.
00:25:04 --> 00:25:06 Um, the last one we were at was the compact,
00:25:06 --> 00:25:09 uh, Muon Solenoid. This is
00:25:09 --> 00:25:12 this machine that's as big as a small factory
00:25:12 --> 00:25:15 in a giant chamber underground. And it's
00:25:15 --> 00:25:17 called the Compact Muon Solenoid. I love
00:25:17 --> 00:25:20 that. Uh, it's definitely not compact
00:25:20 --> 00:25:22 by our, uh, standards, but it was a fantastic
00:25:22 --> 00:25:25 thing to see. We're hoping we might see that
00:25:25 --> 00:25:27 again, but we'll see. Um, so, yeah, we're
00:25:27 --> 00:25:29 nothing to do with the large. Hunt and
00:25:29 --> 00:25:32 Collider were just, um, cheerleaders, uh,
00:25:32 --> 00:25:34 to bring people to cheer it on. Because one
00:25:34 --> 00:25:37 day we hope this machine might tell us what
00:25:37 --> 00:25:39 dark matter is. And that's actually what this
00:25:39 --> 00:25:42 upgrade's about. Uh, so what's happening? Uh,
00:25:42 --> 00:25:44 it's switched off at the moment. I, uh, think
00:25:44 --> 00:25:47 it is now switched off. Uh, see you later.
00:25:47 --> 00:25:50 Accelerator. It's, um, uh,
00:25:50 --> 00:25:53 due to reopen in 2030,
00:25:53 --> 00:25:56 which will be a new version. It's called the
00:25:56 --> 00:25:59 High Luminosity LHC Large
00:25:59 --> 00:26:02 Hadron Collider. And it's got 10 times
00:26:02 --> 00:26:05 the luminosity of the original machine.
00:26:06 --> 00:26:09 Um, and I think by luminosity,
00:26:09 --> 00:26:12 what particle physicists mean is the
00:26:12 --> 00:26:15 number of particles that you can, uh, sort
00:26:15 --> 00:26:17 of charge around, uh,
00:26:18 --> 00:26:20 the circuit, the 27
00:26:20 --> 00:26:23 kilometre, uh, ring that the
00:26:23 --> 00:26:25 particles charge around,
00:26:26 --> 00:26:28 uh, being accelerated and focused by
00:26:28 --> 00:26:30 superconducting magnets. And I think that's
00:26:30 --> 00:26:33 what's actually being, you know, I think
00:26:33 --> 00:26:35 that's what's being, uh, upgraded.
00:26:36 --> 00:26:38 Um, so I don't think the speed will be
00:26:38 --> 00:26:41 faster. Uh, and if I remember rightly, these
00:26:41 --> 00:26:43 protons are accelerated to
00:26:43 --> 00:26:46 9998% of
00:26:46 --> 00:26:47 the speed of light. I think that's the
00:26:47 --> 00:26:50 accurate thing. Uh, so it'll be
00:26:50 --> 00:26:52 probably the same speed but many, many more
00:26:52 --> 00:26:55 particles. And that gives you a much better,
00:26:56 --> 00:26:58 uh, chance of seeing some of the things that
00:26:58 --> 00:27:01 we've missed. We've missed by, uh,
00:27:01 --> 00:27:04 the current version of the lhc, which of
00:27:04 --> 00:27:06 course M is a, ah, triumph
00:27:06 --> 00:27:09 already. And in fact, uh, on the day we're
00:27:09 --> 00:27:11 recording, um, today, 2nd of July,
00:27:12 --> 00:27:14 yesterday was the 12th, sorry,
00:27:14 --> 00:27:17 the 14th anniversary of the discovery of the
00:27:17 --> 00:27:20 Higgs boson, which was done at the Large
00:27:20 --> 00:27:22 Hadron Collider. Wow. So a bit of an
00:27:22 --> 00:27:23 anniversary there.
00:27:23 --> 00:27:24 Andrew Dunkley: That's gone fast, hasn't it?
00:27:24 --> 00:27:27 Professor Fred Watson: Hasn't it gone fast? Yeah, and gosh, I think
00:27:27 --> 00:27:28 we've been talking about it that long as
00:27:28 --> 00:27:31 well, literally and figuratively. Yeah,
00:27:32 --> 00:27:35 that's right, that's right. So,
00:27:35 --> 00:27:37 and of course what we're, and this
00:27:38 --> 00:27:40 ties into our previous storey, what we're all
00:27:40 --> 00:27:43 hoping, uh, for is
00:27:43 --> 00:27:46 that the, uh, new
00:27:46 --> 00:27:48 analysis which will result from
00:27:49 --> 00:27:51 the high luminosity lhc,
00:27:52 --> 00:27:54 uh, will give us insights into everything,
00:27:54 --> 00:27:56 but perhaps in particular the Higgs boson,
00:27:57 --> 00:28:00 and maybe will point the way,
00:28:00 --> 00:28:03 uh, as the Conversation piece says, uh, will
00:28:03 --> 00:28:05 point the way to physics beyond the Standard
00:28:05 --> 00:28:07 model, perhaps including evidence for
00:28:07 --> 00:28:10 supersymmetry or the existence of exotic
00:28:10 --> 00:28:13 dark matter particles. And of course, along
00:28:13 --> 00:28:15 the way we hope they'll solve the Hubble
00:28:15 --> 00:28:16 Tension as well.
00:28:16 --> 00:28:19 Andrew Dunkley: Well, yes, let's hope so. Yeah,
00:28:19 --> 00:28:22 yeah, it's um. So how long does this work
00:28:22 --> 00:28:24 take, you reckon? I think it takes quite some
00:28:24 --> 00:28:25 time, yeah.
00:28:25 --> 00:28:27 Professor Fred Watson: Most of the time between now and 2030 when it
00:28:27 --> 00:28:30 comes back on. So, yeah, I mean
00:28:30 --> 00:28:33 it sounds as though, uh, it
00:28:33 --> 00:28:36 is, are going to involve
00:28:36 --> 00:28:38 replacing all the superconducting magnets all
00:28:38 --> 00:28:41 the way around the 27 kilometre ring
00:28:42 --> 00:28:44 and that. Yeah, that's quite a thing.
00:28:44 --> 00:28:46 Andrew Dunkley: The good news is, if you want a
00:28:46 --> 00:28:48 superconducting magnet, there'll be some for
00:28:48 --> 00:28:49 sale on the side of the road
00:28:52 --> 00:28:54 in a few years time, probably.
00:28:56 --> 00:28:59 Professor Fred Watson: Um, I beg your pardon, I quoted, uh, it as
00:28:59 --> 00:29:00 being from the Conversation, the article I
00:29:00 --> 00:29:02 was reading from, but it's actually Universe
00:29:02 --> 00:29:02 Today.
00:29:02 --> 00:29:04 Andrew Dunkley: Universe Today by Alan Boyle.
00:29:05 --> 00:29:06 Professor Fred Watson: Very good.
00:29:06 --> 00:29:08 Andrew Dunkley: All right, we'll watch with interest and
00:29:08 --> 00:29:11 hopefully an upgraded Cafe as well, which
00:29:11 --> 00:29:13 will, um, you know, bring the tourists in big
00:29:13 --> 00:29:14 time, for sure.
00:29:15 --> 00:29:17 I think that brings us to the end of the
00:29:17 --> 00:29:19 show, Fred Watson. Thank you so much.
00:29:19 --> 00:29:22 Professor Fred Watson: Ah, they go so quickly, don't they?
00:29:22 --> 00:29:24 Andrew Dunkley: They don't. They do. They do, yes.
00:29:25 --> 00:29:27 Professor Fred Watson: Uh, but I'll see you next time, I hope.
00:29:27 --> 00:29:28 Andrew Dunkley: I hope so, too.
00:29:28 --> 00:29:28 Professor Fred Watson: Huh?
00:29:28 --> 00:29:30 Andrew Dunkley: Couldn't do this without you, Fred Watson.
00:29:31 --> 00:29:33 Professor Fred Watson: I don't think I could do it without you.
00:29:34 --> 00:29:35 Andrew Dunkley: At least you'd be able to talk about
00:29:35 --> 00:29:36 something. I'd sit here and go, um.
00:29:37 --> 00:29:38 Professor Fred Watson: No, you wouldn't.
00:29:38 --> 00:29:40 Professor Fred Watson: No, no, you wouldn't. No, you can talk.
00:29:40 --> 00:29:42 Andrew Dunkley: I can talk gibberish. I can do that a lot.
00:29:43 --> 00:29:44 Professor Fred Watson: The hind leg off a donkey.
00:29:44 --> 00:29:46 Andrew Dunkley: That's the time I could do that.
00:29:46 --> 00:29:47 Professor Fred Watson: Yeah.
00:29:47 --> 00:29:49 Andrew Dunkley: I could talk the leg off an iron pot. That's
00:29:49 --> 00:29:49 another one.
00:29:50 --> 00:29:51 Professor Fred Watson: I like that.
00:29:51 --> 00:29:53 Andrew Dunkley: Yeah. All right. Thanks, Fred Watson. We'll
00:29:53 --> 00:29:54 see you soon.
00:29:54 --> 00:29:55 Professor Fred Watson: Sounds great. Thanks, Andrew.
00:29:56 --> 00:29:57 Andrew Dunkley: Professor Fred Watson Watson, astronomer at
00:29:57 --> 00:29:59 large. Don't forget to visit our website
00:29:59 --> 00:30:02 between episodes. You can do that and, uh,
00:30:02 --> 00:30:04 maybe if you've got time, wherever you listen
00:30:04 --> 00:30:07 to us, leave review. Reviews are very helpful
00:30:07 --> 00:30:09 because they tell people what you think
00:30:09 --> 00:30:12 of us and that might inspire them to listen.
00:30:12 --> 00:30:15 It might not, depending on what you say. But,
00:30:15 --> 00:30:18 uh, yeah, reviews are very, very good. If you
00:30:18 --> 00:30:19 can, uh, spend a couple of minutes doing that
00:30:19 --> 00:30:22 from wherever you listen to us.
00:30:22 --> 00:30:24 Um, YouTube,
00:30:25 --> 00:30:28 um, Apple Podcasts, Spreaker. There's a.
00:30:28 --> 00:30:30 There's a whole bunch that we're on. And
00:30:30 --> 00:30:33 thanks to Huw in the studio, who couldn't be
00:30:33 --> 00:30:35 with us today because he's dealing with
00:30:35 --> 00:30:38 a dark matter. And from me, Andrew Dunkley.
00:30:38 --> 00:30:39 Professor Fred Watson: Thanks for your company.
00:30:40 --> 00:30:41 Andrew Dunkley: We'll see you in the next episode of Space
00:30:41 --> 00:30:42 Nuts.
00:30:42 --> 00:30:42 Professor Fred Watson: Bye. Bye.
00:30:44 --> 00:30:46 Andrew Dunkley: You've been listening to the Space Nuts
00:30:46 --> 00:30:49 podcast, available at
00:30:49 --> 00:30:51 Apple Podcasts, Spotify,
00:30:51 --> 00:30:54 iHeartRadio or your favourite podcast
00:30:54 --> 00:30:55 player. You can also stream on
00:30:55 --> 00:30:57 demand@bytes.um.com.
00:30:57 --> 00:30:59 Professor Fred Watson: this has been another quality podcast
00:30:59 --> 00:31:02 production from bytes.um com.

