# The Intricacies of Angular Momentum - What Happens Near Black Holes

An episode of [Space Nuts: Astronomy Insights & Cosmic Discoveries](https://invisiblenetwork.ai/podcast/1080090608), 28 Sep 2026, 30 min.

Audio: https://dts.podtrac.com/redirect.mp3/pscrb.fm/rss/p/op3.dev/e/api.spreaker.com/download/episode/75310734/the_intricacies_of_angular_momentum_what_happens_near_black_holes_nordvpn.mp3

Sponsor Link: This episode of Space Nuts is brought to you with the support of NordVPN.. To check out special money saving deal, visit www.nordvpn.com/spacenuts Space Nuts: Q&A on Radial Velocity, Dark Matter, and Angular Momentum In this engaging Q&A episode of Space Nuts, hosts Andrew Dunkley and Professor Fred Watson tackle a variety of intriguing listener questions, ranging from the complexities of radial velocity in exoplanet detection to the mysteries of dark matter and angular momentum in black holes. Join them as they explore these cosmic conundrums with their characteristic wit and expertise. Key topics - Hussein from Yemen asks about the radial velocity method for detecting exoplanets, prompting a discussion on how astronomers can isolate individual planets from the combined gravitational effects of multiple bodies. - Martin from Maryland raises a thought-provoking question on the potential to harness dark energy for space flight, leading to an exploration of the feasibility of accelerating spacecraft to near-light speeds. - Peter from Sweden inquires about the angular momentum of matter falling into black holes, sparking a conversation on whether this matter retains its momentum or needs to shed some energy before crossing the event horizon. - Andrew and Fred Watson also touch on the ongoing search for Planet Nine and the importance of surveying exoplanets for understanding the universe's structure and potential for life beyond Earth. Timestamps 00:00 - Introduction to the Q&A format and listener questions 01:20 - Hussein's question about radial velocity and exoplanets 10:30 - Martin's inquiry on harnessing dark energy for space travel 18:45 - Peter's question about angular momentum and black holes 26:00 - Discussion on the significance of ongoing exoplanet surveys 32:15 - Closing thoughts and listener engagement Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts-astronomy-insights-cosmic-discoveries--2631155/support.

## Transcript

[0:00] Andrew Dunkley: Hi there. Thanks again for joining us. This
[0:02] is Space Nuts. It's a Q and A edition where
[0:04] we answer audience questions. And,
[0:07] uh, we. I think we've got our very first
[0:10] question from Yemen. Uh, Hussein
[0:12] has sent, uh, it a question asking about
[0:15] radial velocity. Uh, Martin, one of
[0:18] our regular contributors, has a dark matter
[0:20] he wants to discuss. Uh, Peter
[0:23] in Sweden is talking angular momentum.
[0:26] Uh, that is the angular momentum of matter
[0:29] falling into a black hole. And a
[0:32] real bummer of a question. We'll tell you all
[0:34] about it on this episode of space
[0:37] nuts.
[0:38] Professor Fred Watson: 15 seconds. Guidance is internal.
[0:40] 10, 9.
[0:42] Ignition sequence start. Space nuts.
[0:45] Berman Gorvine: 5, 4, 3, 2.
[0:46] Professor Fred Watson: 1, 2, 3, 4, 5, 5, 4, 3,
[0:49] 2, 1.
[0:50] Andrew Dunkley: Space nuts.
[0:51] Professor Fred Watson: Astronauts report it feels good.
[0:54] Andrew Dunkley: And he's back again to solve all your
[0:56] riddles. It's Professor Fred Watson Watson,
[0:58] astronomer at large. Hello, Fred Watson.
[1:01] Professor Fred Watson: Hello, Andrew. Good to see you again. I
[1:03] always hoped we'd get back together again one
[1:05] day and here we've been ages.
[1:09] Andrew Dunkley: About two minutes. Uh, yeah.
[1:12] Um, anyway, I love the
[1:15] Q and A programme, I really do, because it
[1:17] gives people a chance to, um, dump on us
[1:20] and see how much we can mess it up. And
[1:23] that's always fun. Um, we might
[1:26] get straight into it. Fred Watson and
[1:29] I was very excited to see that. We've got a
[1:31] question from Yemen. I never thought we. I
[1:34] didn't even know we were heard in Yemen,
[1:37] so that's really fantastic. And,
[1:39] um, this one comes from Hussain, who says,
[1:42] I'm a huge fan of the podcast Calling in from
[1:44] Yemen. See, I was right. It was Yemen. Ah,
[1:47] First, a quick confession. I hope you're not
[1:48] offended, but Space Nuts is my absolute
[1:51] favourite show to listen to when I'm falling
[1:53] asleep.
[1:57] Your voices are incredibly soothing. Uh,
[1:59] though I promise I do actually listen to the
[2:02] science before I drift off. I
[2:04] appreciate that. Um, my wife says I keep
[2:07] her awake, um, because I snore, but
[2:10] I don't believe it. I've never heard me. Uh,
[2:12] my question is about the radial velocity
[2:15] method for detecting exoplanets. I understand
[2:17] that a star wobbles because of the
[2:19] gravitational pull of its orbiting planets.
[2:22] However, how do astronomers use this
[2:25] method to isolate individual planets? For
[2:27] example, our sun must wobble because Mercury,
[2:30] Venus, Earth, Mars, Jupiter and the rest pull
[2:33] in different directions at the same time. If
[2:35] an alien astronomer were looking at our
[2:38] sun's wobble from across the galaxy, would
[2:40] they actually be able to untangle that
[2:43] messy combined signal to
[2:45] identify individual planets and their
[2:48] specific characteristics?
[2:50] Or does the wobble method just tell us, hey,
[2:53] there are planets here, without giving away
[2:55] the exact Details of who's who. Love
[2:58] the show. Keep up the fantastic work,
[3:00] Hussein. That's a really well crafted
[3:02] question. Thank you, Hussain.
[3:05] Professor Fred Watson: It is a great question as well. Uh, and
[3:08] the answer in a way is both.
[3:11] Um, the two alternatives that
[3:14] Hussein's put forward, uh, can you
[3:16] disentangle them or does the wobble method
[3:18] just tell us, hey, there are planets there,
[3:21] without giving away the exact details and
[3:24] what differentiates
[3:26] between them is first of
[3:29] all how bright the star is, how near it is.
[3:32] So what kind of strength of signal you get in
[3:35] terms of measuring the velocity of the star
[3:37] itself by this Doppler wobble method,
[3:40] uh, to analyse for planets. But also it
[3:43] depends on the sizes of the planets
[3:46] and on their mix, uh, as well.
[3:49] Um, so, uh, just thinking about
[3:52] the solar system, we've got the biggest
[3:55] planet, Jupiter. That's the one that has by
[3:58] far the biggest effect on the sun.
[4:00] Saturn comes next, uh, in terms of its
[4:03] size. And then the other two, uh, gas giants,
[4:06] uh, uh, Uranus and Neptune, uh,
[4:10] the terrestrial planets or rocky planets
[4:13] also have an effect. Uh,
[4:16] but because their masses are much lower, the
[4:19] effect is also much lower.
[4:21] It's mitigated slightly by by the fact that
[4:23] they're nearer to the sun, uh, but
[4:26] nevertheless they're much, much weaker than
[4:28] the gas giants. So if you were, uh,
[4:31] uh, an alien on a planet,
[4:33] uh, orbiting a star maybe eight or nine light
[4:36] years away, something like that, which is the
[4:38] distance to Sirius, uh, the brightest star in
[4:41] the sky, and you're looking back at the solar
[4:43] system, uh, the first thing you
[4:46] would see would be, uh,
[4:48] the main motion which would be due
[4:51] to Jupiter because its mass is so much
[4:54] bigger. The other planets, however,
[4:57] if you had really highly
[5:00] accurate velocity measurements and
[5:03] you'd need them almost to
[5:05] centimetres per second accuracy, uh,
[5:08] it can be done. Uh, there are ways of
[5:10] calibrating spectrographs to let you do this.
[5:13] Uh, but if you did have these really accurate
[5:16] readings and you could do
[5:19] your measurements almost 24 7,
[5:22] which you can't because, uh, certainly if
[5:24] we're anything like the Earth, you've got
[5:26] daylight coming in the way. Uh, but what
[5:29] you want to do is fill in the time domain as
[5:32] full as you can to get as many data
[5:34] points as you can, then what you would
[5:37] do, you'd build up a picture which would
[5:40] be dominated by Jupiter. But the
[5:43] graph of the speed of the star,
[5:46] the wobble of the star would have little ups
[5:49] and downs in it caused by the
[5:52] other planets. Uh, and you
[5:54] can disentangle those. There is
[5:57] a technique called Fourier analysis,
[6:01] uh, it uses, uh, things that we call fast
[6:04] Fourier transforms, which is a mathematical
[6:07] tool that um, kind of dates
[6:10] from the early days of computing, in fact,
[6:12] well before that when people did their
[6:13] calculations by hand. But for this, it's a
[6:16] way of disentangling just how many,
[6:19] what we might call periodicities, in other
[6:21] words, how many regular, um, passages
[6:24] are there, ah, caused
[6:27] by individual planets, if I can put it that
[6:29] way.
[6:30] So you can tease out the effect of
[6:33] each individual planet because they all have
[6:35] different periods of revolution, uh,
[6:37] around the sun. In the case of, if
[6:40] you're looking at the solar system. So, um,
[6:43] if you've got good enough data, you can uh,
[6:46] as Hussein suggests, uh, identify
[6:49] the individual planets and their specific
[6:51] characteristics. But if your data aren't so
[6:53] good, then you're basically just seeing the
[6:56] biggest ones of them. And that's just telling
[6:58] you that there's at least one planet there.
[7:01] Andrew Dunkley: Yeah, early on when we started discovering
[7:04] uh, exoplanets, we were only finding the big
[7:07] ones, weren't we? We assumed there were small
[7:09] ones, but it took us a long time to find the
[7:12] first one, didn't it?
[7:13] Professor Fred Watson: That's right. And in fact, um,
[7:16] it highlights the uh, the
[7:19] deficiencies of the Doppler wobble method,
[7:21] what Hussain was talking about as a way to
[7:23] discover planets, because it's really,
[7:27] that's most sensitive to the biggest ones.
[7:30] Uh, it was when the Kepler spacecraft,
[7:33] uh, and uh, Tess, the
[7:36] other, um, planet finding spacecraft, when
[7:39] they started looking in detail at the way the
[7:42] brightness of stars changed, uh, as
[7:45] planets passed in front of their parent
[7:47] stars. Uh, that's when we
[7:50] started discovering the smaller ones because
[7:52] the smaller ones are actually, uh, easier
[7:55] to discover that way.
[7:57] Andrew Dunkley: Um, here's a dumb question.
[8:01] Can we, can,
[8:04] can we look with accuracy at
[8:07] the wobble of our own sun because of
[8:10] the planets surrounding it, including our
[8:12] own?
[8:13] Professor Fred Watson: Yeah, uh, you can, yes.
[8:16] Um, and um, you
[8:19] can actually find, um, uh,
[8:21] diagrams showing the way.
[8:26] It's what we call the barycenter. The
[8:28] barycenter of the solar system is its
[8:30] centre of gravity, which takes into account
[8:33] not just the sun, uh, but the planets
[8:36] as well. And the barycenter does wander
[8:38] around. Uh, mostly it's inside
[8:41] the sun. It does come outside the sun
[8:44] from time to time. Uh, but uh, you can
[8:47] find charts showing exactly how that happens.
[8:50] Uh, you know, little maps of the way the
[8:51] barycentra of the solar system wanders around
[8:54] relative to the sun.
[8:57] Berman Gorvine: Okay.
[8:57] Andrew Dunkley: I wondered, I didn't know if we
[9:00] could do it within our own sphere. So to
[9:03] speak.
[9:04] Professor Fred Watson: Not a dumb question at all. Absolutely.
[9:05] Andrew Dunkley: There you go. I occasionally ask one that's
[9:08] adequate. Uh, and uh, thank you
[9:11] to Hussain for sending that question in from
[9:14] Yemen. Lovely to hear from you. And you're
[9:16] listening to SpaceNuts with Andrew Dunkley
[9:18] and Professor Fred Watson Watson.
[9:21] Let's take a quick break from the show to
[9:23] tell you about our sponsor, NordVPN.
[9:26] Now, if you travel, work remotely or
[9:28] regularly use public WI fi, having a VPN
[9:31] service can be a very useful layer
[9:34] of online security. NORDVPN
[9:37] encrypts your Internet connection and helps
[9:39] keep your online activity private by hiding
[9:42] your IP address and your location. That
[9:45] means when your connecting from an airport, a
[9:47] hotel, a cafe, uh, or any
[9:50] public network for that matter, you can have
[9:53] a greater level of protection for your
[9:55] Internet traffic. NORDVPN
[9:58] also lets you secure up to 10 devices with a
[10:01] single account. So you can protect your
[10:03] phone, your computer, your tablet, your TV
[10:06] or any other compatible device. And
[10:09] it's not just about privacy. Depending on the
[10:12] plan you choose, NORDVPN also offers security
[10:15] features. Scam and phishing protection, uh,
[10:17] ad and tracker blocker, uh, malware
[10:20] protection, password management. That's the
[10:22] tool I love the most actually the password
[10:24] management system. I would die without it. It
[10:27] is so very handy. You don't have to remember
[10:29] anything except your 1M password to get
[10:32] in to the Nord tool that looks after
[10:34] everything else. There's a 30 day money back
[10:37] guarantee as well, giving you the opportunity
[10:40] to try before you buy and see if it's right
[10:42] for you. And I really do think it will be.
[10:44] They're the best in the business and they're
[10:46] our sponsor. So go to
[10:48] nordvpn.com
[10:50] spacenuts a special URL for space nuts
[10:53] listener, uh, listeners. To find out more,
[10:55] that's nordvpn.com
[10:58] spacenuts and don't forget the code word
[11:00] Space Nuts.
[11:02] Professor Fred Watson: I'm going to step off the land now.
[11:06] That's one small step for man.
[11:11] Berman Gorvine: One
[11:14] Berman Gorvine: Space Nuts.
[11:16] Andrew Dunkley: Let's hit uh, you with an audio question from
[11:18] one of our regular contributors.
[11:21] Berman Gorvine: Hello, Space Nuts.
[11:24] Martin Berman Gorvine here from
[11:27] Potomac, Maryland, usa,
[11:31] writer extraordinaire in many
[11:34] genres. With a
[11:37] slightly less silly, though
[11:40] still highly
[11:42] speculative question.
[11:46] Since dark energy is
[11:49] thought to pervade the entire
[11:52] universe, would it
[11:55] be possible, at least in
[11:58] theory, to harness that energy
[12:02] to drive space flight? And
[12:05] if so, uh, could you make
[12:08] a spacecraft go arbitrarily
[12:11] fast? By that means, you
[12:14] know, 99 point a whole bunch of
[12:17] nines percent of
[12:19] uh, the Speed of light for
[12:22] that extra relativistic
[12:25] Philip. So that when you
[12:29] step out at your destination,
[12:32] the uh, universe has aged
[12:35] significantly, but you,
[12:38] the traveller, have not.
[12:41] Can't wait for the
[12:44] answer. Which will probably involve
[12:47] Professor Watson shooting me down in
[12:50] flames as usual. Berman
[12:53] Gorvine, over and
[12:56] out.
[12:57] Andrew Dunkley: Thanks, Martin. Martin sent me a couple
[13:00] copy, uh, of uh, two of his latest books
[13:02] which I haven't had a chance to, to read and
[13:05] I did promise I would but um, uh, I was too
[13:07] busy writing my own. So, uh,
[13:10] um, but I will get to the.
[13:12] Martin, thanks for sending those in. Uh, fire
[13:14] away, Fred Watson.
[13:17] Professor Fred Watson: To shoot him down. Uh, I have to say these
[13:20] um, these questions do sound like the making
[13:23] of another of Martin's books.
[13:26] Uh, so, uh, you know, putting
[13:29] the ingredients uh, of um,
[13:31] science into the books. It's a great idea if
[13:33] you're going to write science fiction. It's
[13:35] nice to have some science in it as well.
[13:37] Um, yes you do. Um,
[13:41] what Martin's question made me think about
[13:45] was, um, the number of
[13:48] joules of energy contained,
[13:51] represented by dark energy per
[13:54] cubic metre of space.
[13:57] And I've no idea what that is, but I bet per
[13:59] cubic metre it's actually quite small,
[14:03] uh, because um, we only
[14:06] see the effect of dark energy when we look at
[14:08] the universe on a very large scale. When we
[14:11] look, you know, billions of light years out,
[14:14] we start to see its effects. We can
[14:17] tell that the universe has been expanding
[14:19] more rapidly, uh, since the universe was
[14:21] about half its present age. Uh,
[14:24] so I guess, you know, if you imagine
[14:27] a tank full of dark energy,
[14:30] uh, on any kind of human scale,
[14:33] whether it's the size of a, I don't know, you
[14:35] know, the size of the fuel tank on your car
[14:37] or the size of the average supertanker,
[14:40] um, my guess is that the amount of energy
[14:42] that, that would cont would actually be
[14:45] quite small. Um, I'm um, happy to be
[14:48] shot down on that, but I think it would
[14:50] simply because you're looking at uh,
[14:53] um, almost an infinitesimally small
[14:56] volume compared with the volumes that we
[14:58] think about when we're talking about the
[15:00] expansion of the universe and the accelerated
[15:02] expansion of the universe. So,
[15:04] um, how do you bottle it? Well, good
[15:07] question. Uh, that's the first thing
[15:10] you've got to do is find a way of extracting
[15:12] dark energy from space, putting it in a tank.
[15:15] But you might that if you do that on any kind
[15:18] of conceivable scale, you don't have enough
[15:20] to make any difference whatsoever to your
[15:22] spacecraft, let alone accelerate it to
[15:25] 99.99999999% of the
[15:28] speed of light. So, um, I hope
[15:31] that's, uh, suitably satisfactory. Shooting
[15:33] down, Martin.
[15:35] Uh, I don't always shoot your theories down.
[15:37] I think your, uh, ideas are uh, lovely and
[15:40] well worth listening to.
[15:42] Andrew Dunkley: Yes, he's got a way, he's got a way of asking
[15:45] questions that he does. Lots of, Lots of fun.
[15:48] Lots of fun.
[15:48] Professor Fred Watson: He does.
[15:49] Andrew Dunkley: Uh, thank you, Martin. Um, we've got some
[15:52] live listeners, uh, uh, or viewers,
[15:55] um, who messaged us. And remember, uh,
[15:57] James from Cincinnati. Haven't heard from
[15:59] James in ages. Well, he's just popped up to
[16:01] say hello.
[16:02] Professor Fred Watson: So.
[16:02] Andrew Dunkley: Hi James. And uh, a question without
[16:04] notice, um, which sort of goes back to our
[16:07] radial velocity message method of searching
[16:09] for exoplanets. Um, I'm wondering,
[16:11] um, so we already know other suns have
[16:14] planets, so why the extensive investigation
[16:16] to keep searching for more? What's the point?
[16:20] Professor Fred Watson: Oh, it's a good question. Um, so it's all
[16:23] about, it's surveying. Um, basically,
[16:26] uh, astronomers are, uh, inveterate
[16:29] surveyors. It's how we discover
[16:31] the large scale characteristics of the
[16:34] universe. And it's also how we find the
[16:37] outliers, the things that are really
[16:38] peculiar, uh, and that need
[16:41] explanation and that sometimes defy science
[16:44] as we know it and um, often result in
[16:47] physics being rewritten. Uh, so,
[16:51] uh, it's
[16:54] like doing population census studies. It's.
[16:57] Why do you want to know how many people, uh,
[16:59] live in a country? And it's all about,
[17:02] um. Well, in the case of humans, it's all
[17:04] about providing the right resources for them.
[17:07] But in the case of.
[17:10] Why do you want to know how many different
[17:11] kinds of exoplanets there are? It's uh,
[17:14] because we might find exactly what we've just
[17:16] been talking about. The water worlds. Uh, we
[17:18] might find habitable worlds. We might even
[17:20] find a SETI signal from one of them. So,
[17:23] uh, this is very much an important part of
[17:26] the astronomers understanding of the
[17:28] universe. To explore and
[17:31] investigate as many of these things as we
[17:33] can.
[17:34] Andrew Dunkley: Yeah. And of course, the most important
[17:35] reason, if we do a planetary census,
[17:38] we can then introduce an international tax
[17:41] system system or intergalactic tax system,
[17:44] more to the point. Yes.
[17:47] Okay. Uh, you are listening to a Q and A
[17:50] edition of Space Nuts with Andrew Dunkley and
[17:52] Professor Fred Watson Watson.
[17:57] Professor Fred Watson: Three, two, one.
[18:00] Andrew Dunkley: Space Nuts. Our next question comes from
[18:03] Svedon. Uh, can matter
[18:06] that falls into a black hole keep its angular
[18:09] momentum and sort of add it to
[18:11] the black hole's angular momentum? Uh,
[18:14] or does matter Fall into a black hole.
[18:17] Um, or does matter falling into a
[18:20] black hole need to shed its angular momentum,
[18:22] or part of it through radiating, uh, energy
[18:25] out into space before it can fall down the
[18:28] hole? If so, why can't a black
[18:31] hole that can retain light and
[18:34] spaghettify things pull things in despite
[18:37] their angular momentum and just add the
[18:39] incoming momentum to itself? That comes from
[18:42] Peter in Sweden.
[18:45] Uh, it's one of those complicated questions
[18:48] that would have wiped me out at school
[18:50] based on some form of geometry.
[18:56] Professor Fred Watson: Uh, I am, um. So I
[18:59] don't know the answer to this question. Um,
[19:02] but thinking what little I do know
[19:05] about black holes, I would guess. Um,
[19:07] and I'll need to cheque this, Peter. So I
[19:10] apologise that this is an off the cuff
[19:12] answer. But I would guess that the angular
[19:14] momentum does. That it is
[19:17] additive. Uh, that you would add the
[19:20] angular momentum of incoming accreted
[19:22] material which will have it because it's
[19:24] whizzing around the black hole at very high
[19:26] speeds. Um, uh, as the black
[19:29] hole collapse, as the stuff crosses the event
[19:32] horizon and is subsumed into the black hole,
[19:35] uh, I would guess that actually adds to the,
[19:37] to the black hole's angular momentum. But
[19:40] I'll need to cheque. Uh, and I will do that
[19:42] because that's a really good question.
[19:44] Andrew Dunkley: Okay. Well, that was easy.
[19:46] Professor Fred Watson: Yeah, well, it wasn't because I don't know
[19:48] the answer, but. But I'm guessing I,
[19:51] uh, I think it probably would. Yeah.
[19:53] Andrew Dunkley: Actually reminds me, we had one we had to do
[19:56] some homework on recently and I think we've.
[19:59] I don't know if we did it. Anyway, I'll go.
[20:01] Professor Fred Watson: I usually make it. Yeah, I usually make notes
[20:04] on things like that as well. I think you're
[20:06] right too.
[20:07] Andrew Dunkley: Yeah. I might do a whole show on
[20:11] Professor Fred Watson: things we've forgotten.
[20:13] Andrew Dunkley: Things we've forgotten to look up.
[20:15] Professor Fred Watson: Yeah, yeah.
[20:16] Andrew Dunkley: Um, we might get back to you, Peter.
[20:19] Uh, thanks for the question. Um, this
[20:22] question. This question needs
[20:25] setting up because, uh, it's a question,
[20:28] but it's not a question. Uh, and it comes
[20:30] from, uh, Dave. Now, I know people have
[20:33] accidentally called me Dave from time to
[20:35] time. It's nice to have a real Dave. And
[20:38] when I read your question, Dave, I thought, I
[20:40] can't just let you go. I've got
[20:43] to, um, preempt it with something that I
[20:46] thought was appropriate.
[20:48] Professor Fred Watson: Hello, Dave. You're looking well
[20:51] today.
[20:53] Andrew Dunkley: Um, this is Dave.
[20:56] Berman Gorvine: Greetings. This is Dave from Gilbert,
[20:58] Arizona, with apologies in advance for my
[21:01] question. So anyway, I don't know if you, uh,
[21:04] heard about this, but, um, it's been reported
[21:06] that there's something strange in the region
[21:08] of our solar system somewhere between Saturn
[21:10] and Neptune. And I wanted to hear your
[21:13] opinion on the notion that it could be a
[21:15] black hole or a brown dwarf, or possibly a
[21:18] black dwarf or a brown hole out near the
[21:20] orbit of Uranus. So, by
[21:23] the way, uh, some people in the US Government
[21:25] have pooh, poohed this idea, while others
[21:27] from the US Military, such as Colin Powell
[21:30] and several rear admirals, are calling for a
[21:33] probe so we can get to the bottom of this.
[21:36] Now, I was wondering if you can get behind
[21:38] this notion or if you care to rebut it.
[21:40] In either case, I'm looking forward to
[21:42] hearing your posterior analysis.
[21:45] Uh, I also have a question about. Dang
[21:47] it, I gotta go. That's my landlord calling. I
[21:49] must be in arrears again on my rent. I'll
[21:52] have to call you back later with my question,
[21:54] super massive dark matter. Although that
[21:57] may actually be more of a medical question.
[21:59] Anyway, I wanted to say that your podcast is
[22:01] a real asset to the astronomical community.
[22:04] No ifs, ifs, ands, or buts about that. So
[22:07] cheers to you. Slash. Bottoms up.
[22:11] Andrew Dunkley: Ah, that's very clever, Dave. Um, I
[22:14] don't think we've ever had. You ready for
[22:15] this one, Fred Watson? I don't think we've
[22:17] ever had such an asinine
[22:20] question.
[22:23] Professor Fred Watson: Uh, yeah, it's, um. It's got
[22:26] every buzzword in the dictionary in there,
[22:28] hasn't it?
[22:29] Andrew Dunkley: It sure has.
[22:30] Professor Fred Watson: Especially the no if so. But I like that. I
[22:32] loved it. I loved it.
[22:34] Andrew Dunkley: Well done, Dave. I like that he spent
[22:37] time thinking about that and. And come up
[22:39] with. Yeah, all those
[22:42] superlatives.
[22:43] Professor Fred Watson: It's very, very well done. Um, my
[22:46] answer to it is, uh, yes,
[22:49] accreted material does add to the
[22:51] angular momentum of a black hole.
[22:53] Andrew Dunkley: Oh, you looked it up?
[22:55] Professor Fred Watson: I looked it up well, while I was enjoying
[22:57] Dave's question, because I know, having heard
[23:00] it before, that I didn't have to provide an
[23:02] answer to that.
[23:04] Andrew Dunkley: Yeah, actually, the live audience thought
[23:06] that was brilliant, too. We've got some very
[23:08] good remarks about it.
[23:10] Professor Fred Watson: So. Yeah.
[23:10] Andrew Dunkley: And another question, without notice,
[23:12] Fred Watson,
[23:15] when AI first came along,
[23:19] um, the. The questioner can
[23:21] remember that, and. Well, I think we all can.
[23:23] But can Professor Watson
[23:26] say, um, whether or not
[23:29] AI is being used by seti? Didn't
[23:32] we get that question the other day? Or
[23:35] a similar question about the use of AI in,
[23:38] um.
[23:38] In, uh, in astronomy? I don't know if we did
[23:41] it in regard to the search for
[23:43] extraterrestrials yeah.
[23:45] Professor Fred Watson: Yes, we did, we did. About the way it can be
[23:48] used to really tease out
[23:50] information that might otherwise,
[23:53] uh, go unnoticed because of the
[23:56] statistical methods that we use. So,
[23:58] um, uh, it's an
[24:01] intriguing thought though,
[24:04] uh, when you turn it the other way around in
[24:06] regard to seti, whether
[24:09] the putative extraterrestrial intelligence
[24:12] itself is using AI and may even be
[24:15] AI, um, how would we
[24:17] disentangle that from, um,
[24:20] a non AI, um,
[24:22] uh, extraterrestrial entity?
[24:25] It leads us into all kinds of uncharted
[24:27] waters. Does. That's quite an interesting
[24:29] question.
[24:30] Andrew Dunkley: It does indeed.
[24:32] Um, and back to
[24:34] Dave's, uh, tongue in cheek question.
[24:38] Uh, of course there is an
[24:41] object that they think is out there somewhere
[24:44] that we haven't yet found, and that's called
[24:46] Planet Nine. So
[24:48] even though I know, I know where he was
[24:51] coming from, he was, he was being extra
[24:54] funny and the comments are still coming from
[24:56] people who thought it was. Um, but in
[24:59] reality there, there is
[25:01] definitely a possibility of something out
[25:04] there that they haven't found, but they, they
[25:06] know it exists, whether
[25:09] it's a planet or a bunch of stuff,
[25:13] um, that's affecting
[25:17] the outer solar system, I suppose.
[25:19] Professor Fred Watson: Correct. And it's been in the news again
[25:21] recently. Actually. I almost, uh, put it up
[25:23] as one of the topics we should cover that,
[25:26] um, there have been more comments on
[25:28] the possibility of Planet Nine. The original
[25:31] researchers who highlighted this,
[25:34] um, Mike Brown and uh,
[25:38] one of his colleagues, they have
[25:41] basically said that
[25:44] if it's not Planet Nine, there is still
[25:46] something that needs explained, which is more
[25:49] or less what you've just said. Ah, but, um,
[25:51] they are still very confident that we will,
[25:53] uh, unearth a very distant planet, quite
[25:56] a massive one, that is affecting the orbits
[25:59] of these, um, trans neptunian objects,
[26:02] which are, ah, in very elongated orbits.
[26:05] So the jury's still out on it. It's one of
[26:07] these, I think it's one of these questions
[26:08] that we'll talk about for some time to come,
[26:10] Andrew.
[26:12] Andrew Dunkley: And like, the questions are coming, but we
[26:14] can't keep. We can't. Like, we'll be here all
[26:17] day if we go. But, um, back to the AI
[26:20] question.
[26:20] How else has AI been used in
[26:22] astronomy? Uh, I think the possibilities,
[26:25] uh, are endless, aren't they?
[26:28] Professor Fred Watson: Yeah, pretty. Well, um, uh, it's,
[26:30] it's, you know, I mean, people,
[26:33] the main ways, the way I've just described in
[26:36] terms of actually using it to advance
[26:38] astronomy, people use AI, I'm sure, for
[26:41] writing their papers. And I do know one of my
[26:43] colleagues in Arizona uses, uh, AI to
[26:46] mark the papers as well. Oh, uh, wow.
[26:50] Andrew Dunkley: Looking for patterns of people who didn't
[26:53] think for themselves.
[26:55] Professor Fred Watson: I think looking for the whole hug. Um, he
[26:58] presented a paper. This was at a conference.
[27:00] Was it last year or the year before? I think
[27:01] it was the year before last. Uh, which, um,
[27:04] he was very impressed with, um, the,
[27:07] uh, I don't know which breed of AI he was
[27:10] using, but he was very impressed with the
[27:11] outcomes from that and said they actually
[27:14] matched the human marking results,
[27:17] uh, very well. But just
[27:20] aside from that, I think, um, the main use
[27:23] in advancing astronomy is very much in
[27:25] applying it to these very large data sets.
[27:28] Andrew Dunkley: Yeah, I have used it quite a
[27:31] bit, uh, in researching elements of my
[27:34] books when I write. Um, I've already
[27:37] started a prequel to my latest to
[27:40] my new trilogy, which is,
[27:43] um, going well and thanks to everyone who's,
[27:45] who's bought a copy. Uh,
[27:48] and it's lots of fun. I actually, uh,
[27:51] have found a way of using AI,
[27:53] um, that I, uh, really
[27:56] enjoy. It's not just about doing a search,
[27:58] but you can sit there and literally have a
[28:00] conversation and, and weed out information as
[28:03] you go. It's, It's a lot of fun. Um,
[28:06] my wife thought I was, you know,
[28:09] a bit, um, beyond my station using AI
[28:12] because I'm, I'm not a young person. Um,
[28:16] she went to the hairdresser the other day
[28:17] and, um, the hairdresser said, I'm going to
[28:19] redesign my salon. I asked Chat GPT
[28:22] to design it for me. Well, now she's using
[28:25] AI, isn't she? Yeah. Okay. Wouldn't, wouldn't
[28:27] do it if I suggested a it. But
[28:30] the hairdresser, they know everything.
[28:33] Um, okay, thanks to everybody who's
[28:36] sending questions and, uh, our live audience
[28:38] for contributing as well. It's been a lot of
[28:40] fun and thank you, Fred Watson.
[28:42] Uh, that brings us to the end of yet another
[28:44] episode.
[28:46] Professor Fred Watson: It does, doesn't it? Yeah, well, I've learned
[28:48] something in that one. Um, that, uh, yes,
[28:51] angular momentum does, ah, add from
[28:54] accretive material. So there you go.
[28:56] Andrew Dunkley: All right, uh, we'll see you soon,
[28:58] Fred Watson. Thank you.
[29:00] Professor Fred Watson: Cheers.
[29:00] Andrew Dunkley: For now, Professor Fred Watson Watson,
[29:02] astronomer at large. And if you've got
[29:04] questions for us, please jump on our website,
[29:06] spacenutspodcast.com or spacenuts
[29:09] IO if you're a lazy typist. And
[29:12] click on the AMA tab at the top and send us
[29:14] your text or audio questions. Don't forget to
[29:16] tell us who you are and where you're from. We
[29:18] just like to know so that we can spam
[29:21] you later. Uh, and, uh, thanks to
[29:24] Huw in the studio. Um, although Huw couldn't
[29:26] be with us today. Uh, you know, we've
[29:29] been, um, searching for. For Planet nine,
[29:31] which is difficult to find, but I reckon
[29:33] we'll probably find it before we find Huw.
[29:36] And from me, Andrew Dunkley, thanks for your
[29:38] company. We'll see you on the next episode of
[29:40] Space Nuts. Bye.
[29:42] Professor Fred Watson: Bye.
[29:43] Andrew Dunkley: You've been listening to the Space Nuts
[29:45] podcast, available at
[29:48] Apple Podcasts, Spotify,
[29:50] iHeartRadio or your favourite podcast
[29:53] player. You can also stream on
[29:55] demand@bytes.com.
[29:57] Professor Fred Watson: this has been another quality podcast
[29:59] production from bytes.com.
[30:01] Berman Gorvine: um,

Shows are listed from Apple Podcasts' charts and directory, and Podcast Index where it is used. Every show and episode belongs to its publisher and plays from the publisher's own feed; this site hosts none of them.