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Mars Meteor Showers, Gas Giants, and the Search for Alien Civilizations
In this engaging Q&A episode of Space Nuts , hosts Andrew Dunkley and Professor Fred Watson respond to intriguing questions from listeners about our universe. From the risks of meteor showers on Mars to the gravitational effects of Jupiter on its moons, this episode is filled with cosmic curiosities and insightful discussions.
Episode Highlights:
- Meteor Showers on Mars: David from the UK wonders about the potential hazards of meteor showers on Mars, given its thin atmosphere. Andrew and Fred discuss how the reduced atmospheric pressure could allow smaller meteorites to reach the Martian surface and the implications for future human habitation.
- Exploring Gas Giants: Penny asks whether there are plans to fly spacecraft through the atmospheres of Saturn and Jupiter. The hosts explain the challenges of such missions and highlight ongoing projects focused on the fascinating moons of these gas giants instead.
- The Gravitational Dance of Europa: Andy from London seeks clarity on how Jupiter's gravity affects its moon, Europa, without pulling it closer. Andrew and Fred elaborate on the tidal forces at play and how they create the intriguing geological activity observed on Europa.
- The Search for Alien Civilizations: Duncan raises the thought-provoking question of whether we are truly alone in the universe. The hosts discuss the vast distances involved in the Milky Way and the implications for potential communication with extraterrestrial life.
For more Space Nuts, including our continuously updating newsfeed and to listen to all our episodes, visit our website. (https://www.spacenutspodcast.com/) Follow us on social media at SpaceNutsPod on Facebook, Instagram, and more. We love engaging with our community, so be sure to drop us a message or comment on your favorite platform.
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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/32079007?utm_source=youtube
00:00:00 --> 00:00:01 Hello again. Thanks for joining us. This
00:00:01 --> 00:00:05 is a Q&A episode of Space Nuts, where we
00:00:05 --> 00:00:07 answer astronomy and space science
00:00:07 --> 00:00:10 questions from our audience. Today,
00:00:10 --> 00:00:12 David wants to know about Mars meteor
00:00:12 --> 00:00:15 showers. Penny is asking about fly
00:00:15 --> 00:00:17 through missions for Saturn and Jupiter.
00:00:17 --> 00:00:20 That could be messy. Uh Andy is asking
00:00:20 --> 00:00:22 about the gravitational effect of
00:00:22 --> 00:00:25 Jupiter on its uh moons, particularly
00:00:25 --> 00:00:28 Europa. And Duncan wants to talk about
00:00:28 --> 00:00:31 alien civilizations. We will deal with
00:00:31 --> 00:00:34 all of that and more on this episode of
00:00:34 --> 00:00:35 Space Nuts.
00:00:35 --> 00:00:39 >> 15 seconds. Guidance is internal. 10 9
00:00:40 --> 00:00:41 Ignition sequence start.
00:00:41 --> 00:00:42 >> Space Nuts.
00:00:42 --> 00:00:47 >> 5 4 3 2 1 2 3 4 5 4 3 2 1
00:00:47 --> 00:00:48 >> Space Nuts.
00:00:48 --> 00:00:51 >> Astronauts report. It feels good.
00:00:51 --> 00:00:53 >> This is Fred Watson's favorite segment.
00:00:53 --> 00:00:56 He's back again for more. Professor Fred
00:00:56 --> 00:00:58 Watson, astronomer at large. Hello.
00:00:58 --> 00:01:00 Hello, Andrew. How are you?
00:01:00 --> 00:01:02 >> I am quite well. It's been a long time,
00:01:02 --> 00:01:07 like I don't know, two or three minutes.
00:01:07 --> 00:01:09 >> Hope nobody's guessed that we record
00:01:09 --> 00:01:10 these in pairs. But never mind. Never
00:01:10 --> 00:01:11 mind.
00:01:11 --> 00:01:13 >> If they haven't figured it out by now,
00:01:13 --> 00:01:16 they probably never will.
00:01:16 --> 00:01:17 >> That's right.
00:01:17 --> 00:01:19 >> I'm pretty sure most people know how it
00:01:19 --> 00:01:20 works. I mean, they just have to look at
00:01:20 --> 00:01:24 the shirts we're wearing every week.
00:01:24 --> 00:01:25 That's if they do it on the YouTube
00:01:25 --> 00:01:27 channel. Although I don't know if I
00:01:27 --> 00:01:28 don't know if they put the video on
00:01:28 --> 00:01:31 anymore because um it could be could be
00:01:31 --> 00:01:33 a bit bit of a turnoff. So I don't know.
00:01:33 --> 00:01:37 Um anyway, uh all is well with you. I
00:01:37 --> 00:01:38 trust
00:01:38 --> 00:01:39 >> it is. Thank you. Yes. All good.
00:01:39 --> 00:01:41 >> I already knew the answer, but we have
00:01:41 --> 00:01:43 to ask because you know this is just to
00:01:43 --> 00:01:43 be bal.
00:01:44 --> 00:01:46 >> Yes, that's it. Exactly. Um what why
00:01:46 --> 00:01:49 don't we try and answer some questions?
00:01:49 --> 00:01:51 >> Oh, all right. If you must.
00:01:51 --> 00:01:53 >> Well, you do it. I'm just going to push
00:01:53 --> 00:01:55 him in there. Uh, let's go to our first
00:01:55 --> 00:01:57 question. It comes from David
00:01:57 --> 00:02:01 >> David Thompson here from Spring in the
00:02:01 --> 00:02:06 UK. Back to Mars. As a child of the 50s
00:02:06 --> 00:02:08 and 60s,
00:02:08 --> 00:02:11 uh, reading the comics
00:02:11 --> 00:02:14 at the time, there was always a risk of
00:02:14 --> 00:02:18 meteor showers. I'm just wondering given
00:02:18 --> 00:02:23 that Mars atmosphere is not as dense as
00:02:23 --> 00:02:24 the Earth's
00:02:24 --> 00:02:28 whether smaller meteorites would be able
00:02:28 --> 00:02:30 to
00:02:30 --> 00:02:36 hit the surface of Mars and be a real
00:02:36 --> 00:02:41 hazard to anybody putting a house there.
00:02:41 --> 00:02:45 Find the podcast absolutely amazing.
00:02:45 --> 00:02:48 Everybody have a great day. Bye.
00:02:48 --> 00:02:49 Thank you, David. Thanks for those kind
00:02:49 --> 00:02:52 words. I'm glad you're enjoying the the
00:02:52 --> 00:02:54 podcast. Uh so, we're back to Mars. I
00:02:54 --> 00:02:57 didn't push him there. I didn't. Um
00:02:57 --> 00:02:59 everyone knows I love Mars, but uh yeah,
00:02:59 --> 00:03:02 meteor showers. Uh he makes up He brings
00:03:02 --> 00:03:04 up an interesting point. It's got a much
00:03:04 --> 00:03:07 less significant atmosphere than Earth.
00:03:07 --> 00:03:09 So, does that mean smaller things can
00:03:09 --> 00:03:11 get through?
00:03:11 --> 00:03:15 >> It does. Yes, it does. Uh David's
00:03:15 --> 00:03:17 absolutely right. Uh I'm delighted we've
00:03:17 --> 00:03:20 got a listener in Horton Lispring. I um
00:03:20 --> 00:03:22 used to drive past there very very
00:03:22 --> 00:03:24 frequently. It's between Durham and
00:03:24 --> 00:03:26 Sunderland in the north of England. And
00:03:26 --> 00:03:30 I was a very very regular user of the
00:03:30 --> 00:03:32 A1M which goes right past Horton the
00:03:32 --> 00:03:34 spring. Uh and it's lovely to hear your
00:03:34 --> 00:03:37 voice, David, and hear that lovely North
00:03:37 --> 00:03:40 Durham accent there. Um the answer is
00:03:40 --> 00:03:44 yes. Uh uh so because the atmosphere you
00:03:44 --> 00:03:46 know the atmospheric pressure on Mars is
00:03:46 --> 00:03:48 I think it's 6% of our atmospheric
00:03:48 --> 00:03:51 pressure which means that meteorites
00:03:51 --> 00:03:53 coming in are going to have a lot less
00:03:53 --> 00:03:56 resistance. Um we know of meteorites on
00:03:56 --> 00:03:59 Mars. Many have been identified by both
00:03:59 --> 00:04:02 Curiosity and Perseverance uh usually by
00:04:02 --> 00:04:05 their but by their color, but both those
00:04:06 --> 00:04:08 um rovers were equipped with laser
00:04:08 --> 00:04:10 zappers that could give us an idea of
00:04:10 --> 00:04:11 their content. And some of those
00:04:11 --> 00:04:12 meteorites have been found to be
00:04:12 --> 00:04:16 metallic. Uh so meteorites on Mars are
00:04:16 --> 00:04:17 something that happens. And yes, there's
00:04:17 --> 00:04:20 probably a higher risk of uh of damage
00:04:20 --> 00:04:24 from an incoming meteorite on Mars than
00:04:24 --> 00:04:27 on Earth. um because uh the likelihood
00:04:27 --> 00:04:31 is that their terminal velocity uh the
00:04:31 --> 00:04:32 sort of final velocity after they've
00:04:32 --> 00:04:35 passed through the atmosphere will be
00:04:35 --> 00:04:36 much higher than it will be on Earth
00:04:36 --> 00:04:38 just because of that lower pressure.
00:04:38 --> 00:04:42 >> Uh and so yes um me meteorite protection
00:04:42 --> 00:04:44 might turn out to be quite an important
00:04:44 --> 00:04:47 aspect of putting humans on Mars. We
00:04:47 --> 00:04:51 haven't had any reports of you know
00:04:51 --> 00:04:53 there's how many rovers have been on
00:04:53 --> 00:04:55 Mars now? I can think of one, two,
00:04:55 --> 00:04:58 three, four, five, six.
00:04:58 --> 00:05:00 >> At least six, probably more like seven
00:05:00 --> 00:05:04 or eight. Uh they are um Andrew is
00:05:04 --> 00:05:06 googling it as we speak.
00:05:06 --> 00:05:07 >> Yeah.
00:05:07 --> 00:05:08 >> Six.
00:05:08 --> 00:05:10 >> Six rovers. Sojourer, Spirit,
00:05:10 --> 00:05:13 Opportunity, Curiosity, Perseverance,
00:05:13 --> 00:05:16 and uh Jirong, the Chinese mission.
00:05:16 --> 00:05:18 >> The Chinese one. That's right. Yeah,
00:05:18 --> 00:05:20 that So I did get the right answer. Six.
00:05:20 --> 00:05:25 >> Yeah. Uh yeah, it's um so uh none of
00:05:25 --> 00:05:28 those as to the best of our knowledge
00:05:28 --> 00:05:30 has suffered any kind of meteoritic
00:05:30 --> 00:05:34 impact. So at least so far so good in
00:05:34 --> 00:05:37 terms of our understanding of the
00:05:37 --> 00:05:39 meteorite hazard on Mars. But a good
00:05:39 --> 00:05:41 question to raise David and gives us
00:05:42 --> 00:05:43 always always gives us a chance to talk
00:05:43 --> 00:05:46 about Mars. He he did ask about the
00:05:46 --> 00:05:48 danger to housing
00:05:48 --> 00:05:51 on Mars. They probably won't build
00:05:51 --> 00:05:53 houses on Mars like they do on Earth and
00:05:53 --> 00:05:55 and the because of the radiation issues,
00:05:55 --> 00:05:57 they're probably going to have to go
00:05:57 --> 00:06:00 underground which would um protect them
00:06:00 --> 00:06:02 from anything like that. But there will
00:06:02 --> 00:06:04 be surface something or other there one
00:06:04 --> 00:06:05 day.
00:06:05 --> 00:06:06 >> So that's infrastructure.
00:06:06 --> 00:06:09 >> Yeah. Perhaps domes that they could be
00:06:09 --> 00:06:13 susceptible maybe. Yeah, it looks like I
00:06:13 --> 00:06:15 mean what what we imagine is something
00:06:15 --> 00:06:17 like White Cliffs in uh Western New
00:06:17 --> 00:06:19 South Wales where people live
00:06:19 --> 00:06:20 underground.
00:06:20 --> 00:06:20 >> They do.
00:06:20 --> 00:06:22 >> And that's just to get out of the heat.
00:06:22 --> 00:06:23 Um
00:06:23 --> 00:06:24 >> so
00:06:24 --> 00:06:26 >> that's that's radiation.
00:06:26 --> 00:06:28 >> Yes, it is solar radiation. That's
00:06:28 --> 00:06:29 right.
00:06:29 --> 00:06:30 >> Yeah, indeed.
00:06:30 --> 00:06:32 >> Yeah. I thought of another question. Um
00:06:32 --> 00:06:35 we Yeah, here it is. Uh we are
00:06:35 --> 00:06:38 constantly monitoring for big objects
00:06:38 --> 00:06:40 that could be threatening to Earth,
00:06:40 --> 00:06:42 things that could destroy cities or
00:06:42 --> 00:06:45 regions or god forbid the planet itself
00:06:45 --> 00:06:48 as we know it. Uh what about Mars? Do we
00:06:48 --> 00:06:49 keep an eye on anything that might hit
00:06:50 --> 00:06:55 that? Um so yes to some extent if you
00:06:55 --> 00:06:58 you know if you can identify near-Earth
00:06:58 --> 00:07:02 objects uh and look at their orbits you
00:07:02 --> 00:07:04 would certainly find out um from the
00:07:04 --> 00:07:06 analysis very quickly if there was any
00:07:06 --> 00:07:09 risk of one of those hitting the planet
00:07:09 --> 00:07:11 Mars but there's probably many small
00:07:11 --> 00:07:13 objects in the vicinity of Mars because
00:07:13 --> 00:07:15 it's closer to the asteroid belt than we
00:07:15 --> 00:07:18 are uh which are undetectable from the
00:07:18 --> 00:07:21 distance of Earth. Uh, you know, objects
00:07:21 --> 00:07:23 that might even be as big as Phobos,
00:07:23 --> 00:07:25 Mars's biggest moon.
00:07:25 --> 00:07:27 >> Uh, we we we would be able to detect
00:07:27 --> 00:07:29 that from Earth quite easily. But, um,
00:07:29 --> 00:07:30 as we obviously can, it was discovered
00:07:30 --> 00:07:33 in the 1800s. Uh but you know if you had
00:07:33 --> 00:07:36 something that was only a few tens of
00:07:36 --> 00:07:39 meters across uh which could pose a
00:07:39 --> 00:07:44 hazard uh to houses on Mars um that uh
00:07:44 --> 00:07:45 would be hard to detect from the
00:07:46 --> 00:07:48 distance of Earth unless it be unless it
00:07:48 --> 00:07:49 was also a near-Earth object. So it was
00:07:50 --> 00:07:52 coming uh close to closer to our
00:07:52 --> 00:07:53 telescopes.
00:07:53 --> 00:07:56 >> Yeah. Uh there'd be nothing much we
00:07:56 --> 00:07:58 could do about a big thing hitting Mars
00:07:58 --> 00:07:59 anyway is there? Or there'd be a good
00:07:59 --> 00:08:01 experiment if we wanted to test our
00:08:01 --> 00:08:03 capabilities. Well, that's right. If
00:08:03 --> 00:08:04 there was, you know, the the bigger ones
00:08:04 --> 00:08:07 are the the ones that we know more
00:08:07 --> 00:08:09 about, uh, because they're easier to
00:08:09 --> 00:08:11 see. Uh, if something like that was
00:08:11 --> 00:08:13 looking as though it might collide with
00:08:13 --> 00:08:14 Mars,
00:08:14 --> 00:08:17 >> yes, it might be a good time to test out
00:08:17 --> 00:08:19 the theories that were put into place
00:08:19 --> 00:08:21 with the Dart mission a few years ago,
00:08:21 --> 00:08:22 see whether it'll actually work on
00:08:22 --> 00:08:25 something a bit bigger than that.
00:08:25 --> 00:08:27 One can only wonder, but um hopefully we
00:08:28 --> 00:08:30 don't ever have to put it to the test
00:08:30 --> 00:08:33 for for ourselves. But uh yeah, you just
00:08:33 --> 00:08:35 never know. There's always something
00:08:35 --> 00:08:36 going on out there. There's so much
00:08:36 --> 00:08:38 stuff bumping into it. There's something
00:08:38 --> 00:08:40 else out there. It's it's only a matter
00:08:40 --> 00:08:43 of time before one of them carines into
00:08:43 --> 00:08:46 our sector and becomes a potential
00:08:46 --> 00:08:48 threat. Although we seem to be finding
00:08:48 --> 00:08:50 them more and more now, don't we
00:08:50 --> 00:08:52 >> with with and that's the the good news
00:08:52 --> 00:08:54 part of this story. two good news sides
00:08:54 --> 00:08:56 of this story. One is that the big ones
00:08:56 --> 00:08:58 are the easiest to find and the other is
00:08:58 --> 00:09:00 that we've been finding these things now
00:09:00 --> 00:09:02 for the last 40 years and have a good
00:09:02 --> 00:09:04 idea of what the Earth's environments
00:09:04 --> 00:09:05 like.
00:09:05 --> 00:09:07 >> Yeah, great to hear from you, David.
00:09:07 --> 00:09:09 Great question and uh thanks for sending
00:09:09 --> 00:09:12 it in. Our next question comes from
00:09:12 --> 00:09:15 Penny. It's a short quick one. I think I
00:09:15 --> 00:09:17 know where this one might go too in
00:09:17 --> 00:09:19 terms of an answer. As Saturn and
00:09:19 --> 00:09:21 Jupiter are gas giants, are there any
00:09:22 --> 00:09:24 plans to fly a spacecraft through the
00:09:24 --> 00:09:27 middle of one or both of them?
00:09:27 --> 00:09:29 Interesting question, Penny. Uh I do
00:09:29 --> 00:09:32 recall um when you're talking about u
00:09:32 --> 00:09:35 comet or asteroid impacts, the um the
00:09:35 --> 00:09:38 impact with Jupiter uh many many years
00:09:38 --> 00:09:41 ago that we we almost got footage of. It
00:09:41 --> 00:09:43 was just quite not quite the right
00:09:43 --> 00:09:45 angle, but we did see the aftermath of
00:09:45 --> 00:09:46 it.
00:09:46 --> 00:09:50 That's Schumaci the second one Jupiter
00:09:50 --> 00:09:51 back
00:09:51 --> 00:09:53 >> can't remember what year 94 I think it
00:09:53 --> 00:09:59 might have been um so uh the issue is
00:09:59 --> 00:10:03 that um the gas giant aspect of these
00:10:03 --> 00:10:05 planets is really just their outer
00:10:05 --> 00:10:08 envelope that's gassy u and we don't
00:10:08 --> 00:10:11 really know what's underneath that. Uh
00:10:11 --> 00:10:13 the likelihood is there will be a solid
00:10:13 --> 00:10:16 core there. Uh it may be rocky. Some
00:10:16 --> 00:10:19 have suggested that it will be made of
00:10:19 --> 00:10:22 metallic hydrogen which is hydrogen in a
00:10:22 --> 00:10:25 very unusual form. Uh so you've got a
00:10:25 --> 00:10:26 core of something called metallic
00:10:26 --> 00:10:30 hydrogen. So um flying through is not
00:10:30 --> 00:10:32 anything that's planned because it would
00:10:32 --> 00:10:36 be impossible. But even if these gas
00:10:36 --> 00:10:38 giants were sort of gaseous all the way
00:10:38 --> 00:10:41 through, it still would be a very hard
00:10:41 --> 00:10:44 thing to achieve because you're entering
00:10:44 --> 00:10:47 an atmosphere that you'd have to slow
00:10:47 --> 00:10:49 the rocket the spacecraft down
00:10:49 --> 00:10:52 enormously in order to prevent it from
00:10:52 --> 00:10:54 just melting by friction with the
00:10:54 --> 00:10:56 atmosphere, which is what happened to
00:10:56 --> 00:10:58 Cassini. Cassini was plunged into
00:10:58 --> 00:11:00 Saturn's atmosphere at the end of its
00:11:00 --> 00:11:03 mission in 2017. uh it didn't burn up
00:11:03 --> 00:11:05 because there's no oxygen in Saturn's
00:11:05 --> 00:11:07 atmosphere, but the friction made it
00:11:07 --> 00:11:09 melt. Basically, it just melted and fell
00:11:09 --> 00:11:12 to pieces. In fact, NASA produced uh
00:11:12 --> 00:11:14 some real tearjerker footage of what
00:11:14 --> 00:11:16 that might have looked like,
00:11:16 --> 00:11:19 >> which we saw uh often at the end of the
00:11:19 --> 00:11:23 Cassini mission. uh you know this thing
00:11:23 --> 00:11:25 which had performed valiantly for the
00:11:25 --> 00:11:28 previous 13 years and done a marvelous
00:11:28 --> 00:11:30 job at revolutionizing our knowledge not
00:11:30 --> 00:11:31 just of Saturn and its rings and moons
00:11:32 --> 00:11:34 but also the way planets form and things
00:11:34 --> 00:11:37 like that. Uh this footage of uh Cassini
00:11:37 --> 00:11:39 hitting the top of Saturn's atmosphere
00:11:39 --> 00:11:41 and having its antennas ripped off and
00:11:41 --> 00:11:44 eventually just melting into becoming
00:11:44 --> 00:11:46 part of the atoms of the atmosphere of
00:11:46 --> 00:11:50 Saturn. And that is you, you know, any
00:11:50 --> 00:11:52 mission to try and penetrate down
00:11:52 --> 00:11:54 through the atmosphere would would
00:11:54 --> 00:11:58 struggle uh because of the the rapid
00:11:58 --> 00:11:59 increase in density, the fact that
00:11:59 --> 00:12:01 you've got to slow the spacecraft down
00:12:01 --> 00:12:03 in order to stop it just burning up by
00:12:03 --> 00:12:07 friction. Um, I think one of the Jupiter
00:12:07 --> 00:12:11 missions, I can't remember which one,
00:12:11 --> 00:12:14 might have been Galileo, um, actually
00:12:14 --> 00:12:17 sensed as it hits Jupiter's atmosphere
00:12:17 --> 00:12:21 to burn up again or to to melt. I think
00:12:21 --> 00:12:22 there were sensors on board that were
00:12:22 --> 00:12:24 giving us some readings of what the
00:12:24 --> 00:12:26 conditions were like.
00:12:26 --> 00:12:28 >> Yeah. Um,
00:12:28 --> 00:12:30 I I think the other big problem would be
00:12:30 --> 00:12:32 pressure, wouldn't it? if you tried to
00:12:32 --> 00:12:33 fly through.
00:12:33 --> 00:12:37 >> Yeah. So, the pressure just goes up um
00:12:37 --> 00:12:39 probably exponentially at some level.
00:12:39 --> 00:12:41 >> Yeah. Uh and Penny might be interested
00:12:42 --> 00:12:44 to know that there are some missions
00:12:44 --> 00:12:48 slated for um the near future. Uh Europa
00:12:48 --> 00:12:52 Clipper uh which will launch in or it's
00:12:52 --> 00:12:56 already launched should be 20 yeah 2030.
00:12:56 --> 00:12:58 Uh there's the juice mission which
00:12:58 --> 00:13:02 launched in 2023 which arrives in 2031
00:13:02 --> 00:13:04 and Dragonfly
00:13:04 --> 00:13:07 um with with the um with the helicopter
00:13:07 --> 00:13:07 um
00:13:07 --> 00:13:08 >> off to Titan.
00:13:08 --> 00:13:12 >> Yeah, we'll launch in 2028. So they
00:13:12 --> 00:13:15 they're more interested in some of the
00:13:15 --> 00:13:18 um moons around those gas giants, but um
00:13:18 --> 00:13:22 yes, they are fascinating. And of
00:13:22 --> 00:13:24 course, we're most interested in Europa
00:13:24 --> 00:13:26 Clipper because we want to know if
00:13:26 --> 00:13:29 anything's living in the ocean.
00:13:29 --> 00:13:32 And maybe there is, maybe there isn't.
00:13:32 --> 00:13:34 Who knows? It could just be made of
00:13:34 --> 00:13:36 jelly. We we don't really know. Uh
00:13:36 --> 00:13:38 although the juice mission is more
00:13:38 --> 00:13:40 likely to figure all that out. Uh boom
00:13:40 --> 00:13:42 boom. Um thank you, Penny. Lovely to
00:13:42 --> 00:13:44 hear from you. This is Space Nuts Q&A
00:13:44 --> 00:13:47 edition with Andrew Dunley and Professor
00:13:47 --> 00:13:49 Fred Watson.
00:13:49 --> 00:13:51 Let's take a break from the show to tell
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00:15:23 --> 00:15:25 >> Okay, we checked all four systems and
00:15:25 --> 00:15:26 with the go.
00:15:26 --> 00:15:30 >> Space nuts. And speaking of uh Europa
00:15:30 --> 00:15:33 and Jupiter, we've got a a question now
00:15:33 --> 00:15:35 from Andy. This is Andy, the train
00:15:35 --> 00:15:37 driver from London. Uh just got a
00:15:37 --> 00:15:39 question about Europa. I know Europa
00:15:40 --> 00:15:42 erupts because it's being sort of
00:15:42 --> 00:15:45 squeezed by the gravity of Jupiter,
00:15:45 --> 00:15:48 but what I don't understand is if Europa
00:15:48 --> 00:15:51 is being affected by Jupiter's gravity,
00:15:51 --> 00:15:53 why is it not just being pulled closer
00:15:53 --> 00:15:57 to Jupiter? I thought gravity pulls
00:15:57 --> 00:15:59 things down. Like when you throw a ball
00:15:59 --> 00:16:02 in the air, gravity pulls it back down.
00:16:02 --> 00:16:04 I don't understand how Europa is being
00:16:04 --> 00:16:07 squeezed. Uh that suggests to me that
00:16:07 --> 00:16:09 it's being affected by gravity from all
00:16:10 --> 00:16:12 directions. So I squeeze it like a like
00:16:12 --> 00:16:14 you could squeeze a tennis ball. Maybe
00:16:14 --> 00:16:17 you can shed some light on this or tell
00:16:17 --> 00:16:19 me that I'm barking up the wrong tree.
00:16:19 --> 00:16:21 Anyway, thanks for the podcast, guys.
00:16:21 --> 00:16:23 Really interesting. Uh and see you on
00:16:23 --> 00:16:26 the next one. It's Jord's job to bark up
00:16:26 --> 00:16:30 the wrong tree. But um that
00:16:30 --> 00:16:32 >> nicely done, Andrew.
00:16:32 --> 00:16:35 >> Um your point is well taken, Andy. Uh
00:16:35 --> 00:16:37 it's not just Europa, though. Uh there
00:16:37 --> 00:16:39 are several moons orbiting the gas
00:16:39 --> 00:16:41 giants that that do get that squeeze
00:16:41 --> 00:16:43 effect. Titan, I think, is is one of
00:16:43 --> 00:16:47 them. And um oh, look, probably all of
00:16:47 --> 00:16:49 them to some degree, but Europa, yeah,
00:16:49 --> 00:16:53 it's it's it's in a difficult position.
00:16:53 --> 00:16:55 Uh, it's a good question though. Why
00:16:55 --> 00:16:57 don't they just get sucked in? Like our
00:16:57 --> 00:17:00 moon doesn't, but we're not a gas giant.
00:17:00 --> 00:17:02 >> No. Same thing happens to our moon,
00:17:02 --> 00:17:04 though. Um, so, uh, it's actually
00:17:04 --> 00:17:06 probably I think the moon that Andy's
00:17:06 --> 00:17:09 thinking of is Io, which is the
00:17:09 --> 00:17:12 innermost of the of the moons, the the
00:17:12 --> 00:17:14 big moon, big four moons of Jupiter. And
00:17:14 --> 00:17:15 it is the one that gets the most
00:17:16 --> 00:17:19 squeezing and squashing u because of its
00:17:19 --> 00:17:23 uh proximity to to Jupiter. Europa
00:17:23 --> 00:17:25 probably also has the same phenomenon
00:17:25 --> 00:17:28 and there there may be eruptions of it
00:17:28 --> 00:17:32 on Europa that possibly um a bit like
00:17:32 --> 00:17:34 Enceladus where you've got stuff
00:17:34 --> 00:17:36 streaming out through the cracks in the
00:17:36 --> 00:17:37 in the ice.
00:17:37 --> 00:17:40 >> Uh but the the genuine volcanic
00:17:40 --> 00:17:42 eruptions which they really are it's hot
00:17:42 --> 00:17:45 lava uh is what take place on Eio the
00:17:45 --> 00:17:48 innermost of those moons. So um the way
00:17:48 --> 00:17:52 to understand this uh is to real
00:17:52 --> 00:17:56 recognize that if you've got an object
00:17:56 --> 00:17:58 in a very strong gravitational field
00:17:58 --> 00:18:00 first of all let me just clarify the
00:18:00 --> 00:18:03 reason why objects in orbit around other
00:18:03 --> 00:18:05 objects don't just get pulled in. They
00:18:05 --> 00:18:07 are getting pulled in but they've got a
00:18:07 --> 00:18:10 forward motion that compensates for the
00:18:10 --> 00:18:13 for the pull. So basically the the
00:18:13 --> 00:18:16 motion of the object through space uh is
00:18:16 --> 00:18:19 what balances out the gravity of a giant
00:18:19 --> 00:18:22 like Jupiter. And so that you know the
00:18:22 --> 00:18:25 the greater the gravity of a of a planet
00:18:25 --> 00:18:27 the faster it satellites have to orbit
00:18:27 --> 00:18:30 in order not to not to fall in. Um and
00:18:30 --> 00:18:33 so that's that's the mechanism that
00:18:33 --> 00:18:35 stops these things just immediately
00:18:36 --> 00:18:38 being sucked in to Jupiter. They're
00:18:38 --> 00:18:40 already moving and that comes about. Why
00:18:40 --> 00:18:41 are they moving? Because they were
00:18:41 --> 00:18:44 formed that way with the the way the,
00:18:44 --> 00:18:45 you know, the planets and their
00:18:45 --> 00:18:48 satellites evolved, the way they formed.
00:18:48 --> 00:18:50 They're basically swirling around right
00:18:50 --> 00:18:52 from the start. And that swirling motion
00:18:52 --> 00:18:55 is what stops which is fossilized in the
00:18:55 --> 00:18:57 in the planets themselves and and the
00:18:57 --> 00:18:59 moons of the planets and stops them
00:18:59 --> 00:19:02 falling into their parent object. But
00:19:02 --> 00:19:04 the the squeezing and squashing comes
00:19:04 --> 00:19:07 from what we call a tidal effect. And it
00:19:07 --> 00:19:09 is actually exactly the same thing that
00:19:09 --> 00:19:11 gives rise to tides on the earth. Uh but
00:19:11 --> 00:19:13 let's concentrate for a minute on Io.
00:19:13 --> 00:19:16 Here's this little world
00:19:16 --> 00:19:19 right next to gas giant Jupiter. One
00:19:19 --> 00:19:22 side of EO is feeling the gravitational
00:19:22 --> 00:19:25 pull of Jupiter. The other side is as
00:19:25 --> 00:19:27 well, but it's feeling slightly less
00:19:27 --> 00:19:30 because it's further away because the
00:19:30 --> 00:19:33 gravitational pull falls off as as the
00:19:33 --> 00:19:35 distance squared. One over the distance
00:19:35 --> 00:19:38 squared. So um further on the farther
00:19:38 --> 00:19:40 side of EO from Jupiter it's going to
00:19:40 --> 00:19:43 feel less force and that is what con
00:19:44 --> 00:19:45 contributes to this tension that there
00:19:45 --> 00:19:49 is uh and basically elongates the planet
00:19:49 --> 00:19:51 slightly in the direction of Jupiter.
00:19:52 --> 00:19:53 Now
00:19:53 --> 00:19:55 why we talk about squashing and
00:19:55 --> 00:19:57 squeezing is that throughout the orbit
00:19:57 --> 00:19:59 of Vo which is not a planet it's a
00:19:59 --> 00:20:02 satellite but around the orbit of Vo as
00:20:02 --> 00:20:05 it goes around is not circular. So
00:20:05 --> 00:20:07 sometimes that force is greater than
00:20:07 --> 00:20:08 others that tension that's trying to
00:20:08 --> 00:20:11 pull it apart. Uh it's greater than at
00:20:11 --> 00:20:15 other times and and basically it's that
00:20:15 --> 00:20:17 squashing uh stretching really is the
00:20:17 --> 00:20:20 best word for it. As it goes round as it
00:20:20 --> 00:20:22 goes around Jupiter uh that change in
00:20:22 --> 00:20:25 the stretch force that's being applied
00:20:25 --> 00:20:27 is what generates the heat that causes
00:20:27 --> 00:20:30 these eruptions to continually take
00:20:30 --> 00:20:32 place. So and that's called the tidal
00:20:32 --> 00:20:34 effect. the fact that one side of a body
00:20:34 --> 00:20:36 feels a different gravitational force
00:20:36 --> 00:20:38 from the other. It's what makes us
00:20:38 --> 00:20:40 susceptible if we fall into a black hole
00:20:40 --> 00:20:42 to spaghettification.
00:20:42 --> 00:20:44 Spaghettification is just a nicer word
00:20:44 --> 00:20:46 than tidal effects.
00:20:46 --> 00:20:48 >> Yeah. So, you've got a real combination
00:20:48 --> 00:20:49 of of factors.
00:20:49 --> 00:20:50 >> Yeah, that's right. You you've got the
00:20:50 --> 00:20:52 the the gravitational effect, you've got
00:20:52 --> 00:20:54 orbital dynamics.
00:20:54 --> 00:20:54 >> Yep.
00:20:54 --> 00:20:57 >> Um all sort of coinciding to keep these
00:20:57 --> 00:20:59 things from falling into the planet, but
00:20:59 --> 00:21:01 there's a tug of war going on.
00:21:01 --> 00:21:03 >> Yeah. Uh I I saw a really good
00:21:03 --> 00:21:06 demonstration online oh probably three
00:21:06 --> 00:21:09 or four weeks ago on on how the tides
00:21:09 --> 00:21:12 work on Earth. And of course most people
00:21:12 --> 00:21:15 and I must confess guilt here assume
00:21:16 --> 00:21:18 that the moon causes the water to rise
00:21:18 --> 00:21:20 and then fall. But it's not. It's the
00:21:20 --> 00:21:22 fact that the Earth is rotating, the
00:21:22 --> 00:21:25 moon is orbiting, and there's always a
00:21:25 --> 00:21:27 wave. It's just always there. And it's
00:21:27 --> 00:21:30 just that when it um when the moon
00:21:30 --> 00:21:33 reaches your vicinity that that lump of
00:21:33 --> 00:21:35 water comes up.
00:21:35 --> 00:21:36 >> Yeah.
00:21:36 --> 00:21:38 >> And goes down again. It's it's not the
00:21:38 --> 00:21:40 water so much rising. It's just it's
00:21:40 --> 00:21:43 always risen in proximity to the moon.
00:21:43 --> 00:21:44 >> Am I right?
00:21:44 --> 00:21:47 >> Uh you are. You're partly right because
00:21:47 --> 00:21:48 it's a bit more
00:21:48 --> 00:21:49 >> I knew I missed something.
00:21:49 --> 00:21:52 >> Yeah. And the that doesn't explain the
00:21:52 --> 00:21:54 bulge on the other side because as you
00:21:54 --> 00:21:57 know you get a high tide every every 20
00:21:57 --> 00:21:58 hours not every 24 hours.
00:21:58 --> 00:22:01 >> And that's because um again it's the
00:22:01 --> 00:22:04 tidal effect. So the moon's pulling on
00:22:04 --> 00:22:07 the ocean on the near side. It's also
00:22:07 --> 00:22:10 pulling on the earth itself and that
00:22:10 --> 00:22:12 leaves behind the water on the other
00:22:12 --> 00:22:14 side. So you get a bulge
00:22:14 --> 00:22:18 on each side. That's works.
00:22:18 --> 00:22:19 >> Fascinating. Yeah. Yeah, it's worth
00:22:19 --> 00:22:22 looking up that demo. Um I didn't read
00:22:22 --> 00:22:23 the fine print obviously, but uh yeah,
00:22:23 --> 00:22:25 that that makes sense. So the water's
00:22:25 --> 00:22:28 being pulled, sort of dragging with it,
00:22:28 --> 00:22:30 and then the water is being left behind
00:22:30 --> 00:22:31 on the other side. So you got two
00:22:31 --> 00:22:32 bulges.
00:22:32 --> 00:22:34 >> Two bulges. Exactly. So
00:22:34 --> 00:22:35 >> it's fascinating.
00:22:35 --> 00:22:36 >> So
00:22:36 --> 00:22:38 >> um and that's what's happening to all
00:22:38 --> 00:22:41 these these moons in various ways. If
00:22:41 --> 00:22:42 they have not water, something else is
00:22:42 --> 00:22:43 being
00:22:43 --> 00:22:44 >> Well, that's right. It's the rock. The
00:22:44 --> 00:22:46 rock does it as well. The same is true
00:22:46 --> 00:22:48 on Earth. We the rock goes up and down
00:22:48 --> 00:22:50 as well. I've got a question for Andy,
00:22:50 --> 00:22:53 though. Um if he's um ever getting back
00:22:54 --> 00:22:55 to us, I'd like to know what sort of
00:22:55 --> 00:22:56 trains he drives.
00:22:56 --> 00:22:59 >> Uh because um yeah, I'm a bit of a train
00:22:59 --> 00:23:00 nerd myself.
00:23:00 --> 00:23:03 >> Train train drivers are my heroes.
00:23:03 --> 00:23:06 >> Yeah. I live next door to a retired
00:23:06 --> 00:23:07 train driver. So
00:23:07 --> 00:23:10 >> yeah. Um but when we flew into do the
00:23:10 --> 00:23:14 other day, I looked down at the rail
00:23:14 --> 00:23:16 maintenance facility. It's it's a brand
00:23:16 --> 00:23:18 new system uh facility that's just been
00:23:18 --> 00:23:20 built in do and they're fitting out all
00:23:20 --> 00:23:22 the new regional trains and you can see
00:23:22 --> 00:23:25 them all lined up bright red all
00:23:25 --> 00:23:27 >> getting ready to go. They're putting all
00:23:27 --> 00:23:30 the furniture in them and uh uh the
00:23:30 --> 00:23:33 Wi-Fi systems and yeah uh they'll be
00:23:33 --> 00:23:35 rolled out pretty soon. Not not exactly
00:23:35 --> 00:23:38 sure when, but um the plan is soon.
00:23:38 --> 00:23:39 That's the answer to the question
00:23:39 --> 00:23:43 officially. Have you um have you ridden
00:23:43 --> 00:23:45 on um new metro trains here in Sydney?
00:23:46 --> 00:23:47 >> Yes, I have. Yes.
00:23:47 --> 00:23:49 >> So, you'll know that they drive 100
00:23:49 --> 00:23:50 kilometer now with no driver. You can
00:23:50 --> 00:23:52 stand at the front, look out the front
00:23:52 --> 00:23:54 window, and pretend you're driving it.
00:23:54 --> 00:23:56 >> Yeah. And I've done that in a taxi in
00:23:56 --> 00:23:57 San Francisco.
00:23:57 --> 00:23:58 >> Oh, yes, you have.
00:23:58 --> 00:23:59 >> Drives driverless taxis.
00:23:59 --> 00:24:00 >> Driverless taxi.
00:24:00 --> 00:24:02 >> That's next level. That's just amazing.
00:24:02 --> 00:24:03 But yeah. Yeah.
00:24:04 --> 00:24:05 >> Pretty incredible stuff.
00:24:05 --> 00:24:08 >> Thanks, Sandy. Um really enjoyed that
00:24:08 --> 00:24:10 question. And uh yeah, if you want to
00:24:10 --> 00:24:11 tell us what sort of train you drive,
00:24:11 --> 00:24:13 send us another message. We'd um we'd
00:24:13 --> 00:24:16 love to find out.
00:24:16 --> 00:24:20 >> I'm going to step off the land now.
00:24:20 --> 00:24:25 That's one small step for man,
00:24:26 --> 00:24:28 one lead for mankind.
00:24:28 --> 00:24:30 >> Space nuts.
00:24:30 --> 00:24:33 >> Our final question today, Fred, comes
00:24:33 --> 00:24:36 from Duncan. He said, "I've heard that a
00:24:36 --> 00:24:38 group of astrophysicists have calculated
00:24:38 --> 00:24:41 that there are an estimated 1 alien
00:24:41 --> 00:24:43 civilizations spread across the Milky
00:24:43 --> 00:24:46 Way, but the Milky Way is 100 light
00:24:46 --> 00:24:49 years across. How far away would an
00:24:49 --> 00:24:51 advanced civilization have to be in
00:24:51 --> 00:24:54 practical terms to be uncontactable?"
00:24:54 --> 00:24:56 Uh, in other words, uh, are we
00:24:56 --> 00:24:59 realistically given the distances
00:24:59 --> 00:25:02 involved effectively alone?
00:25:02 --> 00:25:04 Uh yes is the answer.
00:25:04 --> 00:25:04 >> Yeah.
00:25:04 --> 00:25:08 >> Uh and it's not just about the distance.
00:25:08 --> 00:25:10 It's also about the time.
00:25:10 --> 00:25:13 >> Um because a thousand civilizations
00:25:13 --> 00:25:16 with a in a galaxy that's 12 billion
00:25:16 --> 00:25:18 years old. Uh they might well have
00:25:18 --> 00:25:21 turned up and gone long ago or still be
00:25:21 --> 00:25:22 in the future.
00:25:22 --> 00:25:25 >> Assume that we all coexist.
00:25:25 --> 00:25:27 >> That's right. And we probably don't.
00:25:27 --> 00:25:30 There's actually um a really nice piece
00:25:30 --> 00:25:32 now. Let me see if I can find it. Uh to
00:25:32 --> 00:25:37 direct uh Duncan to it. Uh it's um on
00:25:37 --> 00:25:40 one of the um SP the science media came
00:25:40 --> 00:25:43 in today. So actually I think is where
00:25:44 --> 00:25:47 is it? Sorry, I've lost it. Uh yeah. Uh
00:25:47 --> 00:25:49 it's it's basically a summary of
00:25:49 --> 00:25:52 thinking by the likes of uh Richard
00:25:52 --> 00:25:56 Fineman uh and other great minds. Um and
00:25:56 --> 00:25:59 the bottom line is it's exactly what
00:25:59 --> 00:26:00 I've been saying. It's not just the
00:26:00 --> 00:26:04 distances, it's the time uh that you're
00:26:04 --> 00:26:07 the era in which you live. And it's very
00:26:07 --> 00:26:11 unlikely that we'd find communicable
00:26:11 --> 00:26:13 civilizations
00:26:13 --> 00:26:16 um within the same time zone that we're
00:26:16 --> 00:26:18 living in, if I can put it that way.
00:26:18 --> 00:26:20 It's actually on uh it is on again on
00:26:20 --> 00:26:23 the brighter side of news. Uh and the
00:26:23 --> 00:26:25 headline is a really very very
00:26:25 --> 00:26:27 thoughtful article, well worth a read.
00:26:27 --> 00:26:29 Interstellar travel is impossible and
00:26:30 --> 00:26:31 aliens haven't visited the earth,
00:26:31 --> 00:26:33 physicists say. And it's because the
00:26:33 --> 00:26:36 laws of physics basically make any kind
00:26:36 --> 00:26:39 of travel uh or or even communication
00:26:39 --> 00:26:41 extremely difficult. The laws of physics
00:26:41 --> 00:26:43 are very rigid uh worth having a look
00:26:43 --> 00:26:44 at.
00:26:44 --> 00:26:46 >> Yeah. Yeah. Indeed. Uh although there's
00:26:46 --> 00:26:48 this new book that I know that's been
00:26:48 --> 00:26:50 written that kind of is counter to all
00:26:50 --> 00:26:52 that, but you can do that in science
00:26:52 --> 00:26:54 fiction
00:26:54 --> 00:26:57 >> quite. So yeah, that's that's why it's
00:26:57 --> 00:26:59 called science fiction.
00:26:59 --> 00:27:02 >> Yes, that's that's what it is. Uh by by
00:27:02 --> 00:27:05 way of example though, if I may, um
00:27:05 --> 00:27:09 Duncan, uh if you were to be aware of a
00:27:09 --> 00:27:11 an advanced communicative civilization
00:27:11 --> 00:27:14 on a rocky planet orbiting Alpha
00:27:14 --> 00:27:17 Centator, for example,
00:27:17 --> 00:27:21 um and you sent them a message, it would
00:27:21 --> 00:27:25 take, I'm just trying to remember, 4.37
00:27:26 --> 00:27:28 years to get there. And that means a
00:27:28 --> 00:27:30 return message if they answered you
00:27:30 --> 00:27:32 immediately
00:27:32 --> 00:27:33 would mean that you would not get a
00:27:34 --> 00:27:38 reply for 8.74 years. Yep. Give or take.
00:27:38 --> 00:27:40 But let's round that out to a decade
00:27:40 --> 00:27:41 because you know what the bureaucracy is
00:27:41 --> 00:27:43 like around Alphasi. They're not going
00:27:43 --> 00:27:45 to you know they're going to they're
00:27:45 --> 00:27:46 going to take a couple of years to
00:27:46 --> 00:27:50 figure out what they want to say.
00:27:50 --> 00:27:51 >> But that's the reality of it, isn't it?
00:27:51 --> 00:27:54 And that's our nearest potential
00:27:54 --> 00:27:55 >> y
00:27:55 --> 00:27:56 >> neighbor.
00:27:56 --> 00:28:00 It's it's it's true and um I mean the
00:28:00 --> 00:28:03 point that this article makes is uh you
00:28:03 --> 00:28:06 know we we live in a bubble of radio
00:28:06 --> 00:28:08 radiation which are all the trans
00:28:08 --> 00:28:10 transmissions from earth that's now
00:28:10 --> 00:28:14 basically 100 uh light years in rad in
00:28:14 --> 00:28:16 radius because we've been sending radio
00:28:16 --> 00:28:19 transmissions for about 100 years. Um
00:28:19 --> 00:28:22 and all right what's that 100 divided by
00:28:22 --> 00:28:24 it's a thousandth of the diameter of the
00:28:24 --> 00:28:27 galaxy. Uh and so you know it's hardly
00:28:27 --> 00:28:32 any distance at all. Uh so yeah it's
00:28:32 --> 00:28:35 it's an unc in a way an uncomfortable
00:28:35 --> 00:28:38 reality. Uh to all intents and purposes
00:28:38 --> 00:28:40 we're alone. We're uncontable. We are
00:28:40 --> 00:28:42 alone. That's it. Good side cuz we're
00:28:42 --> 00:28:44 unlikely to be picked on by any
00:28:44 --> 00:28:48 voracious uh aliens. But Yep.
00:28:48 --> 00:28:51 >> Yeah. Um yeah. I think we got to be
00:28:51 --> 00:28:53 realistic about it. Even if there are a
00:28:53 --> 00:28:56 thousand alien civilizations with
00:28:56 --> 00:29:01 advanced technology in our our galaxy,
00:29:01 --> 00:29:03 we are probably never going to be in a
00:29:03 --> 00:29:06 position to communicate with them or and
00:29:06 --> 00:29:07 and certainly not be able to travel to
00:29:07 --> 00:29:12 them in any um meaningful way. And so
00:29:12 --> 00:29:15 even if we're not alone, we are alone.
00:29:15 --> 00:29:19 >> Yes, that's right. Exactly. um you know
00:29:19 --> 00:29:22 that of that uh thousand civilizations
00:29:22 --> 00:29:24 maybe 500 of them have been and gone and
00:29:24 --> 00:29:28 500 of them are yet to evolve.
00:29:28 --> 00:29:31 >> Do do you um concur with that estimation
00:29:31 --> 00:29:32 or you don't think it's
00:29:32 --> 00:29:36 >> um I look uh I have seen similar figures
00:29:36 --> 00:29:38 being quoted uh not that there's that
00:29:38 --> 00:29:40 number of civilizations but that there
00:29:40 --> 00:29:41 might be that sort of number of
00:29:41 --> 00:29:43 habitable planets that might be
00:29:43 --> 00:29:45 earthlike.
00:29:45 --> 00:29:46 Um,
00:29:46 --> 00:29:48 >> we don't know whether being Earthlike
00:29:48 --> 00:29:50 necessarily means you evolve an
00:29:50 --> 00:29:52 intelligent species.
00:29:52 --> 00:29:54 >> Of course, it has done it once, but
00:29:54 --> 00:29:55 >> but the only time
00:29:55 --> 00:29:57 >> could be and because the circumstances
00:29:57 --> 00:29:59 have to be perfectly right. Although we,
00:29:59 --> 00:30:02 you know, we're assuming humanoid type
00:30:02 --> 00:30:04 carbon based life forms, but there could
00:30:04 --> 00:30:06 be others out there that were created a
00:30:06 --> 00:30:08 completely different way.
00:30:08 --> 00:30:09 >> Yeah. So,
00:30:10 --> 00:30:11 yeah, that's that's the stuff of
00:30:11 --> 00:30:13 imagination at the moment, but it's a
00:30:13 --> 00:30:15 possibility, I suppose. Uh, and of
00:30:15 --> 00:30:17 course we'll look like deals next week
00:30:17 --> 00:30:20 when a massive alien mother ship sets
00:30:20 --> 00:30:22 itself down on top of the White House.
00:30:22 --> 00:30:24 And
00:30:24 --> 00:30:26 >> yeah, to rescue us all.
00:30:26 --> 00:30:28 >> Maybe,
00:30:28 --> 00:30:31 maybe. Oh gosh. Thanks, Duncan. Thanks
00:30:31 --> 00:30:33 to everybody who sent in questions.
00:30:33 --> 00:30:35 Please send them in to us. Oh, I I do
00:30:35 --> 00:30:37 have a bit of homework sort of. Um, we
00:30:37 --> 00:30:39 got a question twice now. I've received
00:30:39 --> 00:30:42 it from Mike in New York. Uh Mike, you
00:30:42 --> 00:30:44 you sent us a question in about black
00:30:44 --> 00:30:47 holes, uh an audio question. The whole
00:30:47 --> 00:30:49 guts of the question got cut off somehow
00:30:49 --> 00:30:52 and so we got the the first we got your
00:30:52 --> 00:30:54 preamble, then you started asking the
00:30:54 --> 00:30:55 question, then there was about 5 hours
00:30:56 --> 00:30:58 of nothing, probably about four, you
00:30:58 --> 00:31:01 know, 20 seconds, and then we heard you
00:31:01 --> 00:31:02 say goodbye. So, we don't actually have
00:31:02 --> 00:31:05 the question. So, if you'd like to send
00:31:05 --> 00:31:07 it again, uh please do. Uh, I don't know
00:31:07 --> 00:31:09 what happened there, but um, you know,
00:31:09 --> 00:31:11 it's the internet, so that's what that's
00:31:11 --> 00:31:14 what happened there. Uh, but yeah, Mike
00:31:14 --> 00:31:16 um would love to get that question so we
00:31:16 --> 00:31:17 can run with it. And any questions you
00:31:18 --> 00:31:20 want to send in via the ask me anything
00:31:20 --> 00:31:21 tab at the top of our website,
00:31:21 --> 00:31:23 spacenutspodcast.com,
00:31:23 --> 00:31:25 spacenuts.io.
00:31:25 --> 00:31:27 And don't forget to tell us who you are
00:31:27 --> 00:31:29 and where you're from. Thank you, Fred,
00:31:29 --> 00:31:31 as always. It's been a lot of fun.
00:31:31 --> 00:31:33 >> Absolutely. It's great questions. Good
00:31:33 --> 00:31:35 to hear everybody's voice and um, nice
00:31:35 --> 00:31:36 to see their questions. Thank you.
00:31:36 --> 00:31:39 Indeed. Uh that's Professor Fred Watson,
00:31:39 --> 00:31:40 astronomer at large. And thanks to Hugh
00:31:40 --> 00:31:43 in the studio. Um couldn't be with us
00:31:43 --> 00:31:46 today. He got stopped by border security
00:31:46 --> 00:31:48 and they realized he was an alien. He
00:31:48 --> 00:31:50 comes from New Zealand. It made sense.
00:31:50 --> 00:31:52 So he's been arrested. Uh he might be
00:31:52 --> 00:31:53 back next week. And from me, Andrew
00:31:53 --> 00:31:55 Dunley. Thanks for your company. We'll
00:31:55 --> 00:31:57 catch you on the next episode of Space
00:31:57 --> 00:31:58 Nuts. Bye-bye.
00:31:58 --> 00:32:01 >> Space Nuts. You've been listening to the
00:32:01 --> 00:32:04 Space Nuts podcast
00:32:04 --> 00:32:07 >> available at Apple Podcasts, Spotify,
00:32:07 --> 00:32:09 iHeart Radio, or your favorite podcast
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00:32:12 --> 00:32:15 byes.com. This has been another quality
00:32:15 --> 00:32:19 podcast production from byes.com.