Tiny Jupiter, Unusual Comet Behavior, and Gravitational Lensing
In this exciting episode of Space Nuts , hosts Andrew Dunkley and Professor Fred Watson delve into some intriguing astronomical discoveries. They discuss the surprising news about Jupiter's size, the strange rotation of Comet 41P, and the fascinating concept of utilizing solar gravitational lensing for deep space exploration.
Episode Highlights:
- Jupiter's Revised Size: The duo explores new measurements from NASA's Juno mission that indicate Jupiter is slightly smaller than previously thought. They discuss the implications of these findings on our understanding of the gas giant's internal structure and atmospheric dynamics.
- The Mystery of Comet 41P: Andrew and Fred reveal the unusual behavior of Comet 41P, which has experienced a significant slowdown in its rotation, potentially reversing its spin direction. They analyze the possible causes of this phenomenon and what it could mean for the comet's future.
- Solar Gravitational Lensing: The hosts dive into the concept of using the Sun's gravitational field as a lens to observe distant exoplanets. They discuss the challenges of reaching the solar gravitational lens focal point and the technologies that might one day make such missions feasible.
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Stay curious, keep looking up, and join us next time for more stellar insights and cosmic wonders. Until then, clear skies and happy stargazing.
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Episode link: https://play.headliner.app/episode/31901861?utm_source=youtube
00:00:00 --> 00:00:01 Hello there. Thanks for joining us yet
00:00:02 --> 00:00:04 again. This is Space Nuts. My name is
00:00:04 --> 00:00:05 Andrew Dunley. Uh we're here to talk
00:00:06 --> 00:00:08 astronomy and space science. And on
00:00:08 --> 00:00:10 today's program, we're going to look at
00:00:10 --> 00:00:13 a tiny weeny itsybitsy Jupiter. Yes,
00:00:13 --> 00:00:15 it's not nearly as big as they thought
00:00:15 --> 00:00:19 it was. In fact, it could lose status as
00:00:19 --> 00:00:21 a consequence of this. Maybe not, but
00:00:21 --> 00:00:23 we'll talk about that. We're also going
00:00:23 --> 00:00:25 to look at a flipping interesting comet
00:00:26 --> 00:00:29 and uh solar gravitational lens focal
00:00:29 --> 00:00:31 points. Could we visit them and what
00:00:31 --> 00:00:33 will that mean? We'll find out on this
00:00:34 --> 00:00:36 episode of Space Nuts.
00:00:36 --> 00:00:40 >> 15 seconds. Guidance is internal. 10 9
00:00:40 --> 00:00:42 Ignition sequence start.
00:00:42 --> 00:00:43 >> Space Nuts.
00:00:43 --> 00:00:48 >> 5 4 3 2 1 2 3 4 5 2 1
00:00:48 --> 00:00:49 >> Space nuts.
00:00:49 --> 00:00:52 >> Astronauts report. It feels good.
00:00:52 --> 00:00:54 >> And joining us again to talk about all
00:00:54 --> 00:00:56 of that stuff and probably a lot more is
00:00:56 --> 00:00:58 Professor Fred Watson, astronomer at
00:00:58 --> 00:00:59 large. Hello, Fred.
00:00:59 --> 00:01:03 >> Hello, Andrew. Good to see you again.
00:01:03 --> 00:01:04 >> Yep. As always,
00:01:04 --> 00:01:06 >> love the hoopy shirt.
00:01:06 --> 00:01:09 >> Oh, yeah. Sorry. It's a very tatty old
00:01:09 --> 00:01:11 one. This shirt should be buttoning it
00:01:11 --> 00:01:12 up. This one's tatty.
00:01:12 --> 00:01:14 >> Tatty, but it's white and it's got more
00:01:14 --> 00:01:15 food on it than I've ever put in his
00:01:16 --> 00:01:16 stomach. So,
00:01:16 --> 00:01:18 >> has it got the Has it got the Space
00:01:18 --> 00:01:19 Notes logo on it?
00:01:19 --> 00:01:22 >> Uh, hang on. I'm I've got one here
00:01:22 --> 00:01:24 somewhere. A Space Nuts logo.
00:01:24 --> 00:01:25 >> Oh, yeah.
00:01:25 --> 00:01:27 >> No, I have It's not on It's not not on
00:01:27 --> 00:01:28 this shirt. It's on the other wide
00:01:28 --> 00:01:30 shirt.
00:01:30 --> 00:01:33 >> But um Where did that logo go?
00:01:33 --> 00:01:35 >> I've lost me logo. Anyway, we'll we'll
00:01:36 --> 00:01:38 find out better than losing your mojo.
00:01:38 --> 00:01:42 >> That's true, too. Yes, indeed. Uh let's
00:01:42 --> 00:01:44 begin because we got a lot to talk
00:01:44 --> 00:01:47 about. This uh first story uh looks at
00:01:47 --> 00:01:49 Jupiter, the biggest planet in our solar
00:01:49 --> 00:01:53 system until we find planet 9. And this
00:01:54 --> 00:01:56 is a story that's suggesting that
00:01:56 --> 00:01:58 Jupiter's not quite as big as we thought
00:01:58 --> 00:02:00 it was.
00:02:00 --> 00:02:04 >> Yeah. It's it shrunk by well 8
00:02:04 --> 00:02:05 kilometers.
00:02:05 --> 00:02:06 >> Yeah.
00:02:06 --> 00:02:09 >> At the equator and 24 kilometers at the
00:02:09 --> 00:02:11 poles. So what this is all about and and
00:02:11 --> 00:02:15 I should just give you the numbers. Uh
00:02:15 --> 00:02:19 so the revised radius of Jupiter at its
00:02:19 --> 00:02:22 equator is 71
00:02:22 --> 00:02:23 kilometers
00:02:23 --> 00:02:27 >> which is actually um I think 4
00:02:27 --> 00:02:30 kilometers less than we thought before.
00:02:30 --> 00:02:33 Uh which doubles up to up to uh 8
00:02:33 --> 00:02:34 kilometers when you're talking about
00:02:34 --> 00:02:37 diameter. uh but its polar radius uh
00:02:37 --> 00:02:39 which is
00:02:39 --> 00:02:43 um 66
00:02:43 --> 00:02:44 and those two numbers are quite
00:02:44 --> 00:02:46 different which is why Jupiter's
00:02:46 --> 00:02:48 flattened but at its poles just as
00:02:48 --> 00:02:51 Saturn is uh but that's actually 24
00:02:51 --> 00:02:54 kilometers less than the previous
00:02:54 --> 00:02:58 estimations so for the diameter. So, um,
00:02:58 --> 00:03:02 it's not a huge amount, but it's
00:03:02 --> 00:03:03 >> not not when you not when you're talking
00:03:03 --> 00:03:05 about the size of the planet. That's
00:03:05 --> 00:03:06 >> exactly that's what I mean. Yeah.
00:03:06 --> 00:03:11 714. So, it's what 140
00:03:11 --> 00:03:13 kilometers or thereabouts in diameter,
00:03:13 --> 00:03:17 which is um Yep. 11 Earth diameters,
00:03:17 --> 00:03:18 which is what we always say.
00:03:18 --> 00:03:22 >> Um, so uh why well, first of all, how
00:03:22 --> 00:03:24 have these measurements been made? Uh
00:03:24 --> 00:03:25 and the answer is that the old
00:03:25 --> 00:03:27 measurements actually go back a long
00:03:27 --> 00:03:30 way. They come from the Voyager and
00:03:30 --> 00:03:34 Pioneer era of the exploration of the
00:03:34 --> 00:03:36 outer planets and that goes back to the
00:03:36 --> 00:03:37 70s and 80s. Oh, it does.
00:03:37 --> 00:03:42 >> Um they uh so what what led to the
00:03:42 --> 00:03:43 diameter or the size of Jupiter that
00:03:44 --> 00:03:47 we've been using since then uh is a is
00:03:47 --> 00:03:49 what's called a radio occultation. So
00:03:49 --> 00:03:53 the spacecraft is behind as it passes
00:03:53 --> 00:03:56 behind Jupiter uh its signals get
00:03:56 --> 00:03:59 refracted actually by uh the atmosphere
00:03:59 --> 00:04:01 of the planet probably scattered as
00:04:01 --> 00:04:03 well. Uh but you can time it very
00:04:03 --> 00:04:06 accurately. Uh you time when the the
00:04:06 --> 00:04:07 spacecraft disappears behind the planet
00:04:07 --> 00:04:10 and you know its trajectory. uh you can
00:04:10 --> 00:04:12 then time when it reappears and from
00:04:12 --> 00:04:14 that you can calculate the and knowing
00:04:14 --> 00:04:16 about Jupiter's motion and the
00:04:16 --> 00:04:17 spacecraft's motion you can calculate
00:04:17 --> 00:04:19 what the diameter is. Uh so those are
00:04:20 --> 00:04:22 the values that we've been using ever
00:04:22 --> 00:04:22 since.
00:04:22 --> 00:04:24 >> Ah you know I think I know where all of
00:04:24 --> 00:04:26 this went wrong. They didn't allow for
00:04:26 --> 00:04:29 it stopping for gas.
00:04:29 --> 00:04:31 >> Um the the planet or the spacecraft?
00:04:31 --> 00:04:32 >> The spacecraft.
00:04:32 --> 00:04:34 >> Well, it's a gas giant. That's right.
00:04:34 --> 00:04:37 The planet's a gas giant. So yes, that's
00:04:37 --> 00:04:38 a good point. Yeah.
00:04:38 --> 00:04:41 >> Um anyway, I let that one pass. Um so,
00:04:41 --> 00:04:45 moving on. Wasn't very good. It was It
00:04:45 --> 00:04:46 was all right for the start of the show.
00:04:46 --> 00:04:49 They usually get better as we go along.
00:04:49 --> 00:04:52 Um it's uh the new measurements come of
00:04:52 --> 00:04:53 course from the spacecraft that is
00:04:54 --> 00:04:56 currently in orbit and working away very
00:04:56 --> 00:04:59 hard uh at at Jupiter in orbit around
00:04:59 --> 00:05:01 the planet and that is Juno. NASA's Juno
00:05:02 --> 00:05:05 mission which has been orbiting Jupiter
00:05:05 --> 00:05:08 since 2016 uh and doing pretty well.
00:05:08 --> 00:05:10 It's Yes. It's a decade since we've had
00:05:10 --> 00:05:12 Juno which gosh it time flies doesn't
00:05:12 --> 00:05:13 it? Sure does.
00:05:13 --> 00:05:16 >> Anyway, um so that's allowed much more
00:05:16 --> 00:05:18 accurate measurements because the space
00:05:18 --> 00:05:20 that Juno spacecraft its orbit is very
00:05:20 --> 00:05:23 well understood. It's fairly close to
00:05:23 --> 00:05:26 Jupiter. Um, but you might think, you
00:05:26 --> 00:05:30 know, well, why are we so keen to know
00:05:30 --> 00:05:33 the diameter of the planet to such a
00:05:33 --> 00:05:36 high degree of accuracy? Uh, and the the
00:05:36 --> 00:05:41 answer is um to do with our model
00:05:41 --> 00:05:44 because it is. Yeah, that's right. It's
00:05:44 --> 00:05:46 to do with our modeling of the planet's
00:05:46 --> 00:05:49 interior. Um because a small difference
00:05:49 --> 00:05:52 like that can make a big difference to
00:05:52 --> 00:05:55 what we imagine the in interior of the
00:05:55 --> 00:05:57 planet is like and remember of course
00:05:57 --> 00:06:00 everybody that Jupiter all we see is its
00:06:00 --> 00:06:02 cloud belts when we look at the planet
00:06:02 --> 00:06:05 we don't see any surface or any hint of
00:06:05 --> 00:06:07 a surface so the internal structure of
00:06:07 --> 00:06:09 Jupiter is something we have to deduce
00:06:09 --> 00:06:12 from other measurements and the the an
00:06:12 --> 00:06:14 accurate measurement of the diameter of
00:06:14 --> 00:06:17 the planet comes into that um so That's
00:06:17 --> 00:06:20 that's the reason it also uh you know
00:06:20 --> 00:06:21 one of the other things that's of
00:06:21 --> 00:06:23 interest in Jupiter is the the behavior
00:06:24 --> 00:06:25 of the atmosphere itself and the winds
00:06:25 --> 00:06:28 that blow in Jupiter's atmosphere and
00:06:28 --> 00:06:30 that also needs an accurate
00:06:30 --> 00:06:33 understanding of the diameter of the
00:06:33 --> 00:06:36 planet. Yeah, I actually I was just
00:06:36 --> 00:06:38 looking at that diagram uh that shows
00:06:38 --> 00:06:42 the different potential diameter
00:06:42 --> 00:06:45 situations based on the behavior of the
00:06:45 --> 00:06:47 planet. And yeah, without wind it loses
00:06:47 --> 00:06:50 another what 14 kilometers in.
00:06:50 --> 00:06:53 >> Yes, that's right. It does. Um if you if
00:06:53 --> 00:06:55 you uh if you imagine the winds aren't
00:06:55 --> 00:06:57 there, it does. It shrinks. So So the
00:06:57 --> 00:07:00 And by 14 kilometers exactly, that's the
00:07:00 --> 00:07:03 radius, not the not the diameter. Um so
00:07:03 --> 00:07:10 um we we have um you know a tiny figure
00:07:10 --> 00:07:12 that looks minuscule compared with the
00:07:12 --> 00:07:14 diameter of the planet itself but it is
00:07:14 --> 00:07:16 important in understanding the upper
00:07:16 --> 00:07:19 atmosphere. It's uh if there were no
00:07:19 --> 00:07:21 winds uh then what we will be seeing
00:07:22 --> 00:07:25 will be 14 kilometers smaller. I I'm
00:07:25 --> 00:07:27 surprised that it's taken us a decade to
00:07:27 --> 00:07:30 figure it out. And Juno is there been
00:07:30 --> 00:07:31 there nearly 10 years.
00:07:32 --> 00:07:36 >> Yeah. Um but maybe um you know the the
00:07:36 --> 00:07:38 accuracy that we're getting with this
00:07:38 --> 00:07:42 relies on many uh passages of Juno
00:07:42 --> 00:07:46 around Jupiter. um there will and
00:07:46 --> 00:07:48 because you're always you know that the
00:07:48 --> 00:07:51 chord that um of the Jupiter's disc that
00:07:52 --> 00:07:54 the planet that the spacecraft flies
00:07:54 --> 00:07:57 behind is different every time. And so
00:07:57 --> 00:08:01 we you probably need to um build up a
00:08:01 --> 00:08:04 statistically significant sample of
00:08:04 --> 00:08:06 entry and egress times when you're
00:08:06 --> 00:08:08 looking at you know the object
00:08:08 --> 00:08:10 disappearing by behind the planet.
00:08:10 --> 00:08:13 Occultation is what we call it. um uh an
00:08:13 --> 00:08:15 occultation is when one object hides
00:08:15 --> 00:08:17 another and that's how you're measuring
00:08:17 --> 00:08:19 uh these diameters. So yeah, it's
00:08:19 --> 00:08:22 probably it's probably taken 10 years
00:08:22 --> 00:08:24 partly to amass the data to give us this
00:08:24 --> 00:08:26 kind of level of accuracy.
00:08:26 --> 00:08:29 >> So okay, how accurate do you think it is
00:08:29 --> 00:08:32 now compared to those early um flybys
00:08:32 --> 00:08:35 with Voyager and Pioneer?
00:08:35 --> 00:08:37 >> That's a really good question actually.
00:08:37 --> 00:08:41 I haven't seen any error estimates on
00:08:41 --> 00:08:44 and um as you know in physics and
00:08:44 --> 00:08:46 certainly in astronomy too you always
00:08:46 --> 00:08:48 need a plus or minus an error estimate
00:08:48 --> 00:08:51 as to you know what the likelihood of
00:08:51 --> 00:08:55 your measurement um being that number is
00:08:56 --> 00:08:58 uh and I haven't seen it for these so I
00:08:58 --> 00:08:59 don't know the answer to that but my
00:08:59 --> 00:09:01 guess is that we're talking about in the
00:09:02 --> 00:09:05 region of a kilometer which is um pretty
00:09:05 --> 00:09:07 impressive for something that diameter
00:09:08 --> 00:09:09 uh and something that's that far away,
00:09:10 --> 00:09:11 half a billion kilometers away.
00:09:12 --> 00:09:12 >> Yeah.
00:09:12 --> 00:09:15 >> So, does this mean that our estimations
00:09:15 --> 00:09:17 of other planets in the solar system are
00:09:17 --> 00:09:19 probably a bit off as well? Uh when you
00:09:19 --> 00:09:22 consider that uh like Neptune, for
00:09:22 --> 00:09:23 example, I think we've only visited
00:09:23 --> 00:09:25 once. Would that be right?
00:09:25 --> 00:09:29 >> Yeah. Yeah, that's right. Uh so, yes, I
00:09:29 --> 00:09:31 I I think you're right. you know, you
00:09:31 --> 00:09:34 certainly the the um estimates of
00:09:34 --> 00:09:37 planets beyond Jupiter and Saturn in
00:09:37 --> 00:09:39 terms of their diameter and physical
00:09:39 --> 00:09:42 characteristics will have much bigger
00:09:42 --> 00:09:44 error limits on them just because we
00:09:44 --> 00:09:45 can't make the measurements as
00:09:45 --> 00:09:47 accurately as you can when you've got a
00:09:47 --> 00:09:50 spacecraft in orbit around one of them.
00:09:50 --> 00:09:53 >> Okay. So, um that's that's a work in
00:09:53 --> 00:09:55 progress. Whenever we go back, we might
00:09:55 --> 00:09:56 be able to
00:09:56 --> 00:09:58 >> fix that. But, uh I don't know. Have
00:09:58 --> 00:10:00 they got any missions planned for
00:10:00 --> 00:10:02 Neptune and Uranus or anything?
00:10:02 --> 00:10:04 >> There's there's always calls for them
00:10:04 --> 00:10:06 because they're such interesting worlds.
00:10:06 --> 00:10:06 >> Yeah.
00:10:06 --> 00:10:08 >> Um but I don't think I mean I think
00:10:08 --> 00:10:11 there are uh there are lots of proposals
00:10:12 --> 00:10:13 but I don't think there's anything
00:10:13 --> 00:10:14 funded. Might be wrong about that.
00:10:14 --> 00:10:16 >> Maybe our listeners can tell me if I'm
00:10:16 --> 00:10:18 wrong about that. They they may well cuz
00:10:18 --> 00:10:20 a lot of the actually we've got one
00:10:20 --> 00:10:23 fellow on Facebook who regularly uh
00:10:23 --> 00:10:24 researches some of the things we talk
00:10:24 --> 00:10:26 about and he publishes his findings on
00:10:26 --> 00:10:28 on the Facebook podcast group.
00:10:28 --> 00:10:29 >> Good on
00:10:29 --> 00:10:32 >> um yeah and I I think it's great. I've
00:10:32 --> 00:10:34 read a few of his um explanations and
00:10:34 --> 00:10:36 they're they're very good. Um so we're
00:10:36 --> 00:10:38 probably going to get sacked but uh it's
00:10:38 --> 00:10:40 um
00:10:40 --> 00:10:44 surprised them sacked us all.
00:10:44 --> 00:10:46 >> Well they they can afford us. that's why
00:10:46 --> 00:10:47 we're still here. Um,
00:10:47 --> 00:10:50 >> well, that's true. Yes, true. Very true.
00:10:50 --> 00:10:51 >> No, it's it's it's a really good
00:10:51 --> 00:10:53 discussion point. So, it sort of keeps
00:10:53 --> 00:10:55 the momentum going when when we discuss
00:10:55 --> 00:10:57 these things. So, I'm sure it'll work on
00:10:57 --> 00:11:00 our uh our tiny Jupiter story. Uh, which
00:11:00 --> 00:11:00 um
00:11:00 --> 00:11:01 >> Good.
00:11:01 --> 00:11:03 >> Yes. Which you can read about at the
00:11:03 --> 00:11:05 daily galaxy.com website or you can read
00:11:05 --> 00:11:09 the paper at Nature Astronomy. This is
00:11:09 --> 00:11:11 Space Nuts with Andrew Dunley and
00:11:11 --> 00:11:17 Professor Fred Watson.
00:11:17 --> 00:11:20 That's agre that's agreement. He's at
00:11:20 --> 00:11:25 for goodness sake. I'm really sorry.
00:11:25 --> 00:11:26 >> Okay.
00:11:26 --> 00:11:28 >> He gets very enthusiastic. Hang on. Hang
00:11:28 --> 00:11:31 on.
00:11:31 --> 00:11:33 >> Space nuts.
00:11:33 --> 00:11:35 >> I I couldn't help but turn that into a
00:11:35 --> 00:11:36 link.
00:11:36 --> 00:11:38 >> It's It's Yeah. Brilliant. I'll tell
00:11:38 --> 00:11:39 him.
00:11:39 --> 00:11:41 >> Oh gosh. It's just too good. It's just
00:11:41 --> 00:11:42 too good. But he was going off his nut
00:11:42 --> 00:11:44 that day, wasn't he?
00:11:44 --> 00:11:45 >> He was.
00:11:46 --> 00:11:48 He was. He does. Yes. He's very highly
00:11:48 --> 00:11:48 strung nut, though.
00:11:48 --> 00:11:50 >> Yes. He is. Well, that that's how he
00:11:50 --> 00:11:52 that's how he greeted us when we visited
00:11:52 --> 00:11:54 you late last year. He came tearing down
00:11:54 --> 00:11:56 the stairs.
00:11:56 --> 00:11:58 >> Yeah. Doing his rooster impersonation.
00:11:58 --> 00:12:00 >> No one could ever rob you, Fred. No one.
00:12:00 --> 00:12:03 >> That's the one good thing about it. Yes,
00:12:03 --> 00:12:04 that is the one good thing.
00:12:04 --> 00:12:06 >> They don't have to be big aggressive
00:12:06 --> 00:12:09 dogs. They they just have to be loud.
00:12:09 --> 00:12:11 >> Or or even, you know, a brush turkey
00:12:11 --> 00:12:12 going past the window in the middle of
00:12:12 --> 00:12:15 the night. That's enough as well.
00:12:15 --> 00:12:17 >> Yes, that's uh that's all it takes
00:12:17 --> 00:12:20 sometimes. Now, let's move on to our
00:12:20 --> 00:12:22 next story. And this this is a story
00:12:22 --> 00:12:25 that's got scientists uh really well,
00:12:25 --> 00:12:27 the headline says scientists stunned.
00:12:27 --> 00:12:30 We're talking about uh a comet that has
00:12:30 --> 00:12:34 done something really really unusual.
00:12:34 --> 00:12:37 Unusual. We're talking about comet 41P.
00:12:37 --> 00:12:39 What's it done this time?
00:12:40 --> 00:12:42 >> Cuz it keeps making the news this one.
00:12:42 --> 00:12:46 >> Yes, it does. Tuttle Jacobini Cresac is
00:12:46 --> 00:12:49 its full name. Uh comet better known as
00:12:49 --> 00:12:53 41P. Uh it's an object uh probably a
00:12:53 --> 00:12:56 kilometer across. A flying iceberg like
00:12:56 --> 00:12:59 basically like comets are. Um and it
00:12:59 --> 00:13:01 orbits the sun I think about every 5 and
00:13:01 --> 00:13:03 a half years. So it's in a what we will
00:13:03 --> 00:13:07 call a short period comet orbit. Um and
00:13:07 --> 00:13:10 it's uh when it passes near the sun, of
00:13:10 --> 00:13:12 course it does what comets do. It uh out
00:13:12 --> 00:13:17 gases uh produces um u basically plumes
00:13:17 --> 00:13:20 of of gas leaving its surface. Um it's
00:13:20 --> 00:13:23 usually water ice being converted
00:13:23 --> 00:13:26 directly to water vapor by the process
00:13:26 --> 00:13:30 known as sublimation. Um uh but what has
00:13:30 --> 00:13:36 been recorded uh in uh uh in fact in
00:13:36 --> 00:13:38 quite a while ago actually I think this
00:13:38 --> 00:13:40 is eight years ago by a NASA spacecraft
00:13:40 --> 00:13:42 observations made by NASA Swift
00:13:42 --> 00:13:47 spacecraft um measuring its rotation and
00:13:47 --> 00:13:51 basically over 60 days what's that sort
00:13:51 --> 00:13:54 of nine weeks or something like that
00:13:54 --> 00:13:58 >> um it slowed down from rotating once
00:13:58 --> 00:14:03 every 20 hours to once every 53 hours.
00:14:03 --> 00:14:05 Uh so that is a you know it's almost a
00:14:05 --> 00:14:09 three factor of three uh in this the um
00:14:09 --> 00:14:12 level of spin that this comet has got.
00:14:12 --> 00:14:12 >> Yeah.
00:14:12 --> 00:14:16 >> Uh and it's there's suggestion
00:14:16 --> 00:14:20 that maybe it's now rotating in the
00:14:20 --> 00:14:24 other direction uh from what it was
00:14:24 --> 00:14:26 before that there's been some sort of
00:14:26 --> 00:14:28 reverse. It hasn't slowed down to about
00:14:28 --> 00:14:31 1/3. It's It's reversed. So, it's it's
00:14:31 --> 00:14:34 slowed down five times
00:14:34 --> 00:14:36 >> cuz it's going back the other way.
00:14:36 --> 00:14:39 >> It could be I mean, part of it could be
00:14:39 --> 00:14:41 due to how you measure the rotation
00:14:41 --> 00:14:43 because it could be tumbling as well.
00:14:43 --> 00:14:45 So, you might be seeing it going the
00:14:45 --> 00:14:46 other way around. But, it does seem to
00:14:46 --> 00:14:48 be I think you're right. It's I think
00:14:48 --> 00:14:49 what you've just said is correct that
00:14:49 --> 00:14:51 it's a it's a reversal, a genuine
00:14:52 --> 00:14:55 reversal of its rotation direction. Um,
00:14:55 --> 00:14:58 so yes, it's it's got much more than a
00:14:58 --> 00:14:59 factor of three. That's right.
00:14:59 --> 00:15:01 >> That kills my theory because my first
00:15:01 --> 00:15:03 thought was, well, this must just be an
00:15:03 --> 00:15:05 observational error. But an
00:15:06 --> 00:15:07 observational error wouldn't get it the
00:15:07 --> 00:15:10 wrong way round, unless of course you
00:15:10 --> 00:15:11 you're talking about the color of the
00:15:11 --> 00:15:15 universe, but we won't go there. But um,
00:15:15 --> 00:15:18 >> wasn't my fault.
00:15:18 --> 00:15:21 >> Um, so yeah. Uh, what else could be
00:15:21 --> 00:15:24 causing this change of behavior? it. I
00:15:24 --> 00:15:26 think if if it was anything other than a
00:15:26 --> 00:15:29 comet, you know, if it was an asteroid
00:15:29 --> 00:15:33 doing this or a planetisimal or or a a
00:15:33 --> 00:15:35 distant one of the distant Kyper belt
00:15:35 --> 00:15:37 objects or something like that, it was
00:15:37 --> 00:15:40 if it was any of those, we would be
00:15:40 --> 00:15:42 utterly gobsmacked. Uh because there's
00:15:42 --> 00:15:44 no physical mechanism to do that other
00:15:44 --> 00:15:47 than an interaction with another body.
00:15:47 --> 00:15:49 You know, if you had two bodies
00:15:49 --> 00:15:51 gravitating close together, it could
00:15:52 --> 00:15:54 have an effect on the rotation.
00:15:54 --> 00:15:56 >> But, uh, in fact, more especially a
00:15:56 --> 00:15:58 collision, that would do it as well. Um,
00:15:58 --> 00:16:00 but with a comet, you've got this
00:16:00 --> 00:16:02 process that it outgasses. what I was
00:16:02 --> 00:16:05 saying earlier as it gets near the sun
00:16:05 --> 00:16:09 um the there basically the ices start to
00:16:09 --> 00:16:12 vaporize and you get a thrust from the
00:16:12 --> 00:16:16 from the outgassing material uh which is
00:16:16 --> 00:16:17 what we call a non-gravitational
00:16:17 --> 00:16:21 perturbation. It's when uh when you know
00:16:21 --> 00:16:23 the the outgassing material is acting
00:16:23 --> 00:16:25 like a rocket engine and it's changing
00:16:26 --> 00:16:29 the dynamics of the object as it's
00:16:29 --> 00:16:31 orbiting the sun. Um, and you can
00:16:31 --> 00:16:35 imagine that if there was um a formation
00:16:35 --> 00:16:38 of ice on the on the surface of the
00:16:38 --> 00:16:41 comet that essentially tilted the blast
00:16:41 --> 00:16:46 of the of the um escaping material uh as
00:16:46 --> 00:16:49 it as it sublimated as the as the um the
00:16:49 --> 00:16:52 material the water mostly went straight
00:16:52 --> 00:16:55 from a solid to a gas. Um it's like
00:16:55 --> 00:16:57 having a you know a sort of verier
00:16:57 --> 00:16:59 thruster. It's like where you've got a a
00:16:59 --> 00:17:01 thrust that is changing the rotation of
00:17:01 --> 00:17:04 a spacecraft because it's not going um
00:17:04 --> 00:17:07 the line of of the of the thrust is not
00:17:07 --> 00:17:09 going through the center of gravity of
00:17:09 --> 00:17:11 the comet. If it's off the center of
00:17:11 --> 00:17:12 gravity, then it's going to impart a
00:17:12 --> 00:17:14 rotation on it. And if it's strong
00:17:14 --> 00:17:16 enough, then it might be enough to slow
00:17:16 --> 00:17:18 it down and perhaps even reverse its uh
00:17:18 --> 00:17:21 reverse its rotation. So that's what the
00:17:21 --> 00:17:22 thinking is, but it's never been seen
00:17:22 --> 00:17:23 before.
00:17:23 --> 00:17:26 >> No. Well, like retro rockets.
00:17:26 --> 00:17:29 >> Yeah, that's right. is a retro rocket,
00:17:29 --> 00:17:32 but one that that's not slowing it down
00:17:32 --> 00:17:34 in its orbit. It's changing its rotation
00:17:34 --> 00:17:35 because of the angle that the the
00:17:35 --> 00:17:37 rocket, if you want to call it that, the
00:17:38 --> 00:17:40 rocket exhaust is coming out.
00:17:40 --> 00:17:43 >> Yeah. At the moment, it's 774 million
00:17:43 --> 00:17:47 kilometers from Earth, 5.18 astronomical
00:17:47 --> 00:17:51 units. And uh as you mentioned, this
00:17:51 --> 00:17:54 unusual behavior was checked back in
00:17:54 --> 00:17:59 2017 and they've only just sort of put a
00:17:59 --> 00:18:01 paper together to try and explain it. Um
00:18:01 --> 00:18:04 it's got a 5.4 year orbit, so it comes
00:18:04 --> 00:18:05 back quite often.
00:18:05 --> 00:18:08 >> Yeah, that's right. It's um it it's it's
00:18:08 --> 00:18:11 capt basically captured by Jupiter.
00:18:11 --> 00:18:13 >> So its orbit is dictated. It would have
00:18:13 --> 00:18:15 been in its early history, it would have
00:18:15 --> 00:18:17 been a comet coming into the inner solar
00:18:18 --> 00:18:20 system from the or cloud, this spherical
00:18:20 --> 00:18:22 sort of reservoir of comets. Um, but
00:18:22 --> 00:18:25 would have had its orbit modified maybe
00:18:25 --> 00:18:26 several times by the influence of
00:18:26 --> 00:18:29 Jupiter, which is why it's now in this
00:18:29 --> 00:18:33 really short um short period orbit, 5.4
00:18:33 --> 00:18:34 years. Yeah.
00:18:34 --> 00:18:37 >> Um there has been a suggestion that if
00:18:38 --> 00:18:39 you've got these sort of oblique
00:18:39 --> 00:18:41 outgassing that we've just been talking
00:18:41 --> 00:18:43 about that would change the rotation of
00:18:43 --> 00:18:47 the object that that might also signal
00:18:47 --> 00:18:48 that there might be weaknesses in the
00:18:48 --> 00:18:51 comet structure and it may even be a
00:18:51 --> 00:18:53 precursor to it breaking up which is
00:18:53 --> 00:18:55 something that I think will be observed
00:18:55 --> 00:18:58 with great interest as to how it uh how
00:18:58 --> 00:19:01 it progresses uh since since this change
00:19:01 --> 00:19:01 of spin.
00:19:01 --> 00:19:03 >> Yeah, maybe. And we we'll find we could
00:19:03 --> 00:19:06 find out as late as or as soon as late
00:19:06 --> 00:19:08
00:19:08 --> 00:19:11 I think is its next appearance near the
00:19:11 --> 00:19:14 sun or near us or whatever you like. So
00:19:14 --> 00:19:15 um
00:19:15 --> 00:19:19 >> yeah we'll keep an eye on 41p I guess
00:19:19 --> 00:19:21 >> 41p that's right. Um there was a
00:19:21 --> 00:19:26 proposal long long ago uh to send a
00:19:26 --> 00:19:28 spacecraft to it because it's a short
00:19:28 --> 00:19:30 period comet. So it's always in the
00:19:30 --> 00:19:32 inner solar system and that was what was
00:19:32 --> 00:19:35 then called Ezro European Space Research
00:19:35 --> 00:19:38 Organization the the precursor of the
00:19:38 --> 00:19:40 European Space Agency. Uh this is in the
00:19:40 --> 00:19:43 1960s. They looked at sending a probe to
00:19:43 --> 00:19:45 that comet but they changed their mind
00:19:45 --> 00:19:47 so it never went.
00:19:47 --> 00:19:51 >> A yes. I'm sure that happens a lot in in
00:19:51 --> 00:19:54 astronomy. I mean, it's not an easy not
00:19:54 --> 00:19:58 an easy thing to um to do to to, you
00:19:58 --> 00:20:00 know, set up a mission and actually
00:20:00 --> 00:20:01 execute it. You got to come up with the
00:20:01 --> 00:20:05 dollars and Yeah. You know, it's only
00:20:05 --> 00:20:07 only so many 10-centent pieces can fit
00:20:07 --> 00:20:10 on a jar on the mantle piece. So,
00:20:10 --> 00:20:12 >> yeah. Yeah, that's right.
00:20:12 --> 00:20:15 >> Yeah. All right. Um, you can read all
00:20:15 --> 00:20:19 about uh comet 41P
00:20:19 --> 00:20:22 uh at um it's at the daily galaxy.com
00:20:22 --> 00:20:23 website, but you can also read the
00:20:23 --> 00:20:26 paper. I think it's just uh been
00:20:26 --> 00:20:29 pre-published or pre there's a pre-print
00:20:29 --> 00:20:32 available uh on the archive. Uh this is
00:20:32 --> 00:20:34 Space Nuts. Andrew Dunley here with
00:20:34 --> 00:20:38 Professor Fred. What's that?
00:20:38 --> 00:20:42 >> I'm going to step off the limb now.
00:20:42 --> 00:20:47 That's one small step for man,
00:20:47 --> 00:20:50 one leap for mankind.
00:20:50 --> 00:20:52 >> Space nuts.
00:20:52 --> 00:20:54 >> Now, Fred, to our final story on this
00:20:54 --> 00:20:57 episode, we've talked many times about
00:20:57 --> 00:20:59 gravitational lensing and some of the
00:20:59 --> 00:21:01 strange things that it does. You can
00:21:01 --> 00:21:03 watch something happen two, three, four
00:21:03 --> 00:21:06 times over the course of many years
00:21:06 --> 00:21:07 because of gravitational lensing because
00:21:07 --> 00:21:11 the light is redirected and takes longer
00:21:11 --> 00:21:12 to get here. And so you can see
00:21:12 --> 00:21:14 something and go, "Oh, what was that?
00:21:14 --> 00:21:16 Hang on. I'll I'll know again in a
00:21:16 --> 00:21:18 couple of years." Because
00:21:18 --> 00:21:21 yeah, not quite. But um what we're
00:21:21 --> 00:21:22 talking about in
00:21:22 --> 00:21:23 >> Yeah.
00:21:23 --> 00:21:24 >> What we're talking about in this
00:21:24 --> 00:21:27 particular case though is actually going
00:21:27 --> 00:21:31 out to a solar gravitational lens focal
00:21:31 --> 00:21:33 point. Is that the crux of the story?
00:21:33 --> 00:21:36 >> It it is. That's right. It's a this is a
00:21:36 --> 00:21:38 really interesting kind of essay really
00:21:38 --> 00:21:42 on the universe today website by Andy
00:21:42 --> 00:21:45 Thomas Wick uh about um about the solar
00:21:45 --> 00:21:47 gravitational lens and about how you'd
00:21:47 --> 00:21:49 get there. Um but the solar
00:21:49 --> 00:21:51 gravitational lens itself is really
00:21:51 --> 00:21:54 interesting. So the idea is exactly as
00:21:54 --> 00:21:57 you've said if you've got a an object of
00:21:57 --> 00:21:59 any mass and it happens with planets as
00:21:59 --> 00:22:03 well as stars uh it's going to bend the
00:22:03 --> 00:22:05 light passing around it because it's
00:22:05 --> 00:22:08 distorting space uh under the uh under
00:22:08 --> 00:22:12 the protocols introduced by um not in
00:22:12 --> 00:22:14 sorry as we understand it by the
00:22:14 --> 00:22:16 protocols introduced by Einstein's
00:22:16 --> 00:22:18 general theory of relativity that's what
00:22:18 --> 00:22:20 lets us calc do all the calculations
00:22:20 --> 00:22:22 about this sort of So, you've got an
00:22:22 --> 00:22:24 object in space. It's bending the light
00:22:24 --> 00:22:26 around it, which means it acts kind of
00:22:26 --> 00:22:28 like a lens. It's a very odd sort of
00:22:28 --> 00:22:32 lens, though. Um, I've seen a glass kind
00:22:32 --> 00:22:34 of interpretation of a gravitational
00:22:34 --> 00:22:38 lens. Um, there's a specialist who uh
00:22:38 --> 00:22:40 who works on this stuff in Melbourne who
00:22:40 --> 00:22:42 showed me her glass version of a
00:22:42 --> 00:22:45 gravitational lens. And it it resembles,
00:22:45 --> 00:22:47 you know, the the bottom of a wine glass
00:22:47 --> 00:22:49 where the the stalk comes up out of the
00:22:49 --> 00:22:51 middle of that. I I know them very well,
00:22:51 --> 00:22:52 Fred.
00:22:52 --> 00:22:54 >> Yeah. Yeah. Um well, if you break the
00:22:54 --> 00:22:57 wine glass off and you're left with that
00:22:57 --> 00:22:59 sort of flared part at the bottom,
00:22:59 --> 00:23:01 that's more or less the same as a
00:23:01 --> 00:23:02 gravitational lens in the way it would
00:23:02 --> 00:23:04 act on the light going around it.
00:23:04 --> 00:23:06 >> So, it's not it's not like a magnifying
00:23:06 --> 00:23:08 glass, which is what you'd like it to
00:23:08 --> 00:23:11 be. It's this very peculiar cuspshaped
00:23:11 --> 00:23:16 lens. And so it gives you um a focus
00:23:16 --> 00:23:19 that is blurred, but it's because you
00:23:19 --> 00:23:21 know the properties of the of the object
00:23:21 --> 00:23:23 that's doing the lensing. And in this
00:23:23 --> 00:23:25 case, we're talking about the sun. Uh
00:23:25 --> 00:23:27 because you know the properties of the
00:23:27 --> 00:23:29 sun, you can calculate what that
00:23:29 --> 00:23:32 blurring does to the image and you can
00:23:32 --> 00:23:34 essentially compensate it. So you could
00:23:34 --> 00:23:36 recreate
00:23:36 --> 00:23:38 uh the light coming from a very distant
00:23:38 --> 00:23:42 object um and recreate the image that
00:23:42 --> 00:23:44 the sun is forming as though it was a
00:23:44 --> 00:23:46 proper lens rather than a peculiar
00:23:46 --> 00:23:49 cusped lens. And that's what's sort of
00:23:49 --> 00:23:51 being proposed. Could we send a
00:23:51 --> 00:23:55 spacecraft to uh the solar gravitational
00:23:55 --> 00:24:00 lens focus where you could look directly
00:24:00 --> 00:24:03 back at a planet on the other side of
00:24:03 --> 00:24:07 the sun around a distant star? So you're
00:24:08 --> 00:24:10 looking into another solar system a long
00:24:10 --> 00:24:12 way away, but you're using the sun's
00:24:12 --> 00:24:15 gravity to bend that light by relativity
00:24:15 --> 00:24:18 and focus it to a point. Uh, and if you
00:24:18 --> 00:24:21 put a spacecraft there with a camera and
00:24:21 --> 00:24:23 a fancy computer, you might be able to
00:24:23 --> 00:24:26 reveal continents on an exoplanet, for
00:24:26 --> 00:24:28 example.
00:24:28 --> 00:24:30 >> Um, or even cities. That's the sort of
00:24:30 --> 00:24:33 thing that people are thinking of. So,
00:24:33 --> 00:24:35 here's the snag, though. That's a great
00:24:35 --> 00:24:36 idea, but snag.
00:24:36 --> 00:24:39 >> I think I just read that exact paragraph
00:24:40 --> 00:24:41 as you were about to say it, so I might
00:24:41 --> 00:24:43 blow the whistle.
00:24:43 --> 00:24:45 >> Yeah. Well, you can.
00:24:45 --> 00:24:47 >> No, no, you do it. It it's the distance,
00:24:47 --> 00:24:50 isn't it? It's it's Yeah. Um about
00:24:50 --> 00:24:53 somewhere between 650 and 900
00:24:53 --> 00:24:55 astronomical units is what's quoted in
00:24:55 --> 00:24:57 this in this article. And an
00:24:57 --> 00:24:59 astronomical unit is 150 million
00:24:59 --> 00:25:02 kilometers. So it is a number with a lot
00:25:02 --> 00:25:07 of zeros after it in kilometers. Um and
00:25:07 --> 00:25:09 you know it's getting your spacecraft
00:25:09 --> 00:25:11 there that is the issue. Uh we're
00:25:11 --> 00:25:13 talking about well the estimate here is
00:25:14 --> 00:25:15 four times further than Voyager 1 has
00:25:15 --> 00:25:19 traveled and that as we know is 23 light
00:25:19 --> 00:25:23 hours away. Um they reckon that it would
00:25:23 --> 00:25:28 be um more than another 130 years to uh
00:25:28 --> 00:25:31 for Voyager 1 to get to the the sun's
00:25:31 --> 00:25:34 gravitational lens point. By my
00:25:34 --> 00:25:36 calculation, and and this is probably
00:25:36 --> 00:25:39 way wrong, 97
00:25:39 --> 00:25:41 million kilometers.
00:25:41 --> 00:25:43 >> Sounds about right. Sounds like a lot.
00:25:43 --> 00:25:43 >> Yep.
00:25:44 --> 00:25:45 >> I didn't think my calculator could fit
00:25:45 --> 00:25:48 that many numbers on it.
00:25:48 --> 00:25:50 >> Remember the old the old calculators
00:25:50 --> 00:25:51 when they first came out? If you gave it
00:25:51 --> 00:25:53 too big a problem, it would just give
00:25:53 --> 00:25:54 you a little E.
00:25:54 --> 00:25:55 >> Yeah.
00:25:55 --> 00:25:57 >> E for error. No, I can't do that. Sorry.
00:25:57 --> 00:25:59 >> Yep. Yeah. This computer says no,
00:25:59 --> 00:26:00 really, isn't it?
00:26:00 --> 00:26:02 >> That's right. Yeah, that's a long way
00:26:02 --> 00:26:06 away and very difficult to achieve, but
00:26:06 --> 00:26:08 I think one day maybe we could do that.
00:26:08 --> 00:26:10 >> Yes. So that that's really the thrust of
00:26:10 --> 00:26:12 this article. How about you know what's
00:26:12 --> 00:26:16 the way to do it? Can you can you get to
00:26:16 --> 00:26:19 that point and they um the author's done
00:26:19 --> 00:26:21 some nice calculations which I haven't
00:26:21 --> 00:26:23 checked so I hope these are correct. I
00:26:23 --> 00:26:27 should check them. Anyway, um if you
00:26:27 --> 00:26:29 were trying to get to that solar
00:26:29 --> 00:26:32 gravitational lens point, focal point in
00:26:32 --> 00:26:34 20 years, then you need your spacecraft
00:26:34 --> 00:26:38 to travel at about 150 kilometers/s.
00:26:38 --> 00:26:43 Um uh it's which is very hard uh when
00:26:43 --> 00:26:45 you're pointing away from the sun. The
00:26:45 --> 00:26:47 Parker Solar Probe, they point out, and
00:26:48 --> 00:26:49 we kind of know this because we've
00:26:49 --> 00:26:51 talked about it, has actually got to
00:26:51 --> 00:26:53 nearly 200 kilometers/s,
00:26:53 --> 00:26:55 but that's only when it's at what we
00:26:55 --> 00:26:57 call perihelion. It's at its closest
00:26:57 --> 00:26:59 point to the sun where it's going
00:26:59 --> 00:27:02 fastest. Um, and what we're talking
00:27:02 --> 00:27:03 about here is something going in the
00:27:03 --> 00:27:05 opposite direction, going away from the
00:27:05 --> 00:27:07 sun. For it to travel at that sort of
00:27:07 --> 00:27:09 speed, you need an extraordinary amount
00:27:09 --> 00:27:12 of thrust. Um, I don't think you're
00:27:12 --> 00:27:14 talking about chemical rockets to get up
00:27:14 --> 00:27:16 to 150 kilometers/s.
00:27:16 --> 00:27:17 >> Light sales.
00:27:17 --> 00:27:20 >> So, light sails. Yeah, that's uh one of
00:27:20 --> 00:27:22 the things that you and I have spoken
00:27:22 --> 00:27:24 about before. If you can
00:27:24 --> 00:27:28 >> beam out laser light to a solar sail, a
00:27:28 --> 00:27:31 gigantic um piece of, you know,
00:27:31 --> 00:27:33 something very thin like myar that's
00:27:33 --> 00:27:35 reflective. Uh then the light itself
00:27:35 --> 00:27:37 pushes it along and you just keep going
00:27:37 --> 00:27:39 so that it just keeps up building up
00:27:39 --> 00:27:40 speed.
00:27:40 --> 00:27:42 >> Um there are um
00:27:42 --> 00:27:44 >> the trouble with that is when you get
00:27:44 --> 00:27:46 there, how do you stop it?
00:27:46 --> 00:27:47 >> Yeah, you don't. You just keep going.
00:27:47 --> 00:27:48 That's right.
00:27:48 --> 00:27:50 >> Unless Unless it had something on board
00:27:50 --> 00:27:54 to like you turn off the light and
00:27:54 --> 00:27:57 >> reverse or something. I don't know.
00:27:57 --> 00:27:58 >> Yeah. You're never going to slow it down
00:27:58 --> 00:28:01 because even if you turn off the light,
00:28:01 --> 00:28:03 it stops it accelerating, but it's still
00:28:03 --> 00:28:05 going at that speed. That's right.
00:28:05 --> 00:28:11 >> Um there's a a possibility that um you
00:28:11 --> 00:28:14 know, could you could you do the solar
00:28:14 --> 00:28:19 sail trick um and and
00:28:19 --> 00:28:23 basically um make it successful? The
00:28:23 --> 00:28:25 problem with solar sales is you you can
00:28:26 --> 00:28:28 only carry objects that are very light
00:28:28 --> 00:28:30 in weight or have low mass. And you
00:28:30 --> 00:28:33 might remember we've looked at this uh
00:28:33 --> 00:28:35 with um what was it the Breakthrough
00:28:35 --> 00:28:38 Starshot program which I think has now
00:28:38 --> 00:28:40 ceased. Breakthrough Starshot looked at
00:28:40 --> 00:28:42 the feasibility of using a solar sail to
00:28:42 --> 00:28:45 send a a spacecraft to Proxima Centuri
00:28:45 --> 00:28:48 which is only four light years away. Um,
00:28:48 --> 00:28:51 and uh, it could be done, but your
00:28:51 --> 00:28:54 spacecraft would basically consist of
00:28:54 --> 00:28:57 uh, one um, what's it called? Printed
00:28:57 --> 00:29:00 circuit board and a detector. Uh,
00:29:00 --> 00:29:01 there's not really room for anything
00:29:01 --> 00:29:03 else. It will be so it'd have to be so
00:29:03 --> 00:29:05 light in weight. It would be measured in
00:29:05 --> 00:29:09 grams rather than kilograms or tons. Uh,
00:29:09 --> 00:29:11 so that would be the problem with your,
00:29:11 --> 00:29:13 you know, with sending a a spacecraft to
00:29:13 --> 00:29:16 the uh, solar gravitational lens using a
00:29:16 --> 00:29:18 solar sail. So, you're talking then
00:29:18 --> 00:29:20 about nuclear sources and uh things of
00:29:20 --> 00:29:24 that sort that this very nice article uh
00:29:24 --> 00:29:27 goes into some of the uh the nicities of
00:29:27 --> 00:29:29 nuclear thermal propulsion and things of
00:29:29 --> 00:29:33 that sort. Even so, it's still a very
00:29:33 --> 00:29:37 tough ask to send a spacecraft to that
00:29:37 --> 00:29:40 interesting part of the sun's
00:29:40 --> 00:29:43 environment where you've got the solar
00:29:43 --> 00:29:47 the solar um uh gravity forming a focus.
00:29:47 --> 00:29:50 Uh even to get there, it's really to get
00:29:50 --> 00:29:53 there in, you know, 20 years or so, uh
00:29:53 --> 00:29:54 you're talking about really new
00:29:54 --> 00:29:55 technologies that we simply don't have
00:29:56 --> 00:29:57 at the moment.
00:29:57 --> 00:29:59 >> Yeah. Well, one day it might be a long
00:29:59 --> 00:30:02 way off, but uh the time may come and uh
00:30:02 --> 00:30:03 but then again, we might have figured
00:30:03 --> 00:30:07 everything out by then. So, yeah.
00:30:07 --> 00:30:09 Yeah. I mean, you you know, the other
00:30:09 --> 00:30:12 thing is you'd want to choose So, you've
00:30:12 --> 00:30:13 got to choose the direction that you go
00:30:13 --> 00:30:14 in.
00:30:14 --> 00:30:14 >> Yeah.
00:30:14 --> 00:30:16 >> Uh to be in the opposite direction to
00:30:16 --> 00:30:18 the planet that you want to observe.
00:30:18 --> 00:30:21 >> Y the exoplanet. And if you get that
00:30:21 --> 00:30:23 wrong, if you choose a a planet that's
00:30:23 --> 00:30:25 completely boring and has no surface
00:30:25 --> 00:30:27 features whatsoever,
00:30:27 --> 00:30:30 uh then you uh you don't really
00:30:30 --> 00:30:31 contribute much to our knowledge,
00:30:31 --> 00:30:32 particularly our knowledge of whether
00:30:32 --> 00:30:34 we're alone or not, whether there's life
00:30:34 --> 00:30:35 anywhere else.
00:30:35 --> 00:30:36 >> It's sort of like leaving the lens cap
00:30:36 --> 00:30:39 on the camera when you land on a Venus.
00:30:39 --> 00:30:40 >> Yes, that's right.
00:30:40 --> 00:30:42 >> Actually, they didn't leave it on. It
00:30:42 --> 00:30:43 melted on. I think
00:30:43 --> 00:30:46 >> it it Yeah. Well, one of them fell off
00:30:46 --> 00:30:48 as well, didn't it? fall offs on top of
00:30:48 --> 00:30:50 the on top of the scale that was going
00:30:50 --> 00:30:52 to give the uh the you know there's a
00:30:52 --> 00:30:55 ruler that they jettisoned to give the
00:30:55 --> 00:30:57 camera something to look at so you could
00:30:57 --> 00:30:59 measure the size of things and the lens
00:30:59 --> 00:31:00 cap landed right on top of it. I think
00:31:00 --> 00:31:02 that's what happened. We've had quite a
00:31:02 --> 00:31:05 few venous disasters over the years, but
00:31:05 --> 00:31:07 yeah, you're right. This would be very
00:31:07 --> 00:31:10 very difficult to swallow if you're
00:31:10 --> 00:31:12 bugging it up cuz you couldn't go and
00:31:12 --> 00:31:13 fix it. Not like
00:31:13 --> 00:31:15 >> Yeah. Well, that's right. You can't move
00:31:15 --> 00:31:17 it in any direction. You You're stuck on
00:31:17 --> 00:31:18 one planet really.
00:31:18 --> 00:31:21 >> Indeed. But it's it's food for thought
00:31:21 --> 00:31:23 though. Um but one day we'll figure out
00:31:23 --> 00:31:26 a way. If you'd like to read about that
00:31:26 --> 00:31:29 story, it is at univertoday.com as Fred
00:31:29 --> 00:31:31 said. And we're done. Fred, thank you
00:31:31 --> 00:31:32 very much.
00:31:32 --> 00:31:35 >> Oh, uh, yeah, that was that was great to
00:31:35 --> 00:31:36 talk about all those things. I hope
00:31:36 --> 00:31:37 we'll do it again sometime.
00:31:37 --> 00:31:39 >> Fun topics. I'm sure we will. Uh, if you
00:31:39 --> 00:31:42 would like to, um, visit us in the
00:31:42 --> 00:31:44 meantime. Don't forget to visit our
00:31:44 --> 00:31:46 website, spacenutspodcast.com or
00:31:46 --> 00:31:49 spacenuts.io IO or visit our social
00:31:49 --> 00:31:51 media platforms, the official Space Nuts
00:31:51 --> 00:31:54 Facebook page or Instagram page or
00:31:54 --> 00:31:56 YouTube channel or whatever you like. Or
00:31:56 --> 00:31:59 if you want to talk to likeminded Space
00:31:59 --> 00:32:01 Nutters, you can do that on the Space
00:32:02 --> 00:32:04 Nuts podcast group on Facebook, which is
00:32:04 --> 00:32:06 always a lot of fun. Thanks, Red. We'll
00:32:06 --> 00:32:07 see you soon.
00:32:07 --> 00:32:09 >> Yes, I hope so.
00:32:09 --> 00:32:11 >> Well, he said that. And uh thanks to
00:32:11 --> 00:32:13 Hugh in the studio um who couldn't be
00:32:13 --> 00:32:15 with us today. He was invited by a
00:32:16 --> 00:32:18 friend to see a comet and he couldn't
00:32:18 --> 00:32:20 wait so he ran over there. It turned out
00:32:20 --> 00:32:21 to be a goldfish.
00:32:21 --> 00:32:24 Some people will get that. And from me,
00:32:24 --> 00:32:27 Andrew Dunley, thanks for your company.
00:32:27 --> 00:32:28 See you on the next episode of Space
00:32:28 --> 00:32:29 Nuts. Bye-bye.
00:32:29 --> 00:32:30 >> Space Nuts.
00:32:30 --> 00:32:33 >> You've been listening to the Space Nuts
00:32:33 --> 00:32:35 podcast.
00:32:35 --> 00:32:38 >> Available at Apple Podcasts, Spotify,
00:32:38 --> 00:32:40 iHeart Radio, or your favorite podcast
00:32:40 --> 00:32:43 player. You can also stream on demand at
00:32:43 --> 00:32:46 byes.com. This has been another quality
00:32:46 --> 00:32:50 podcast production from byes.com.