Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / SpaceX Innovations, Super-Puff Planets & the Mysterious South Atlantic Anomaly

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SpaceX Innovations, Super-Puff Planets & the Mysterious South Atlantic Anomaly · Space Nuts: Astronomy Insights & Cosmic Discoveries

• 0:00
  Andrew Dunkley: Hello again. Thanks for joining us on Space
• 0:02
  Nuts where we talk astronomy and space
• 0:04
  science each and every week. Twice a week in
• 0:07
  fact. My name is Andrew Dunkley, your host.
• 0:09
  It is good to have your company. Coming up on
• 0:12
  today's episode, we're going to get the
• 0:14
  latest from SpaceX and uh, they've got bigger
• 0:17
  and better plans as well. Uh, what about low
• 0:20
  cost space telescopes? Well, there's a
• 0:22
  man we're about to speak to who knows all
• 0:24
  about those because his university is
• 0:26
  involved. Uh, another weird exoplanet
• 0:29
  has been discovered and magnetic, magnetic
• 0:32
  field issues here on Earth. We'll talk about
• 0:35
  all of that on this episode of Space
• 0:38
  Nuts. 15 seconds. Guidance is
• 0:40
  internal. 10, 9.
• 0:43
  Ignition sequence start. Space Nuts
• 0:46
  5, 4, 3, 2.
• 0:47
  Jonti Horner: 1.
• 0:48
  Andrew Dunkley: 2, 3, 4, 5, 5, 4, 3, 2,
• 0:50
  1. Space Nuts astronauts report it
• 0:53
  feels good. Joining us once again to
• 0:56
  talk about all of that and plenty more, I'm
• 0:58
  sure, is Jonti Horner and he is
• 1:01
  a professor of astrophysics at University of
• 1:04
  Southern Queensland. Hello Jonti.
• 1:06
  Jonti Horner: Good morning. How are you going?
• 1:07
  Andrew Dunkley: I am m well. What about you?
• 1:10
  Jonti Horner: Oh, not too bad. I'm recovering. I just spent
• 1:12
  a weekend on the Barrier Reef doing outreach.
• 1:14
  I've got a lovely friendship with a small
• 1:17
  island at the southern end of the Barrier
• 1:18
  Reef that I've been going to for 13 years or
• 1:21
  so. And so Fred gets to go jetting all around
• 1:23
  the world and go to Scandinavia and I get
• 1:26
  to go to the Barrier Reef, which is still
• 1:28
  really, really awesome, to be honest. So, uh,
• 1:30
  I went out there and did an outreach talk and
• 1:33
  some stargazing every night, which reminded
• 1:35
  of the that the most distant object I can see
• 1:38
  with the naked eye is not the Andromeda
• 1:39
  Galaxy, but it's a Triangulum galaxy, which
• 1:42
  is very obvious to me from a dark site
• 1:44
  fainter than Andromeda. Um, that's actually
• 1:46
  my background at the m minute because
• 1:48
  photographing it from home, um, a few weeks
• 1:51
  ago, um, I am very, very keen
• 1:54
  at some point to try and find Centaurus there
• 1:56
  with the naked eye, which I'm reliably told
• 1:59
  that some people with particularly eagle eyes
• 2:01
  can spot from here in the southern
• 2:03
  hemisphere. But for me, Triangulum's it,
• 2:05
  not Andromeda. We've all seen Andromeda, so
• 2:07
  that was great.
• 2:08
  But then today has been a little bit feral
• 2:11
  because there have been a few articles gone
• 2:13
  out about the Orionid meteor shower which we
• 2:16
  mentioned on the podcast a couple of weeks
• 2:17
  ago. And so suddenly the journalists have
• 2:20
  realized it's happening today and have been
• 2:21
  wanting to talk about it today. And I've been
• 2:23
  trying to disappoint everybody and make
• 2:26
  Australians miserable by pointing out that
• 2:27
  it's not the awesome spectacle that some of
• 2:30
  the AI garbage would have you believe.
• 2:32
  Andrew Dunkley: Yeah, of course. And there's plenty of AI
• 2:34
  garbage these days. And it's just getting
• 2:36
  worse.
• 2:37
  Jonti Horner: Some of the AI generated images that are
• 2:39
  popping up on Facebook, I mean, they're
• 2:41
  pretty, but they're pretty in the same way
• 2:43
  that a Picasso painting is in that they don't
• 2:45
  really bear much reality to the reality that
• 2:48
  we see. They're rather totally, totally
• 2:50
  speculative. And it makes me a little bit
• 2:52
  sad, um, that they're convincing enough even
• 2:55
  though they're incredibly wrong. The people
• 2:57
  who don't know much about the subject get
• 2:59
  really hyped up and then get really
• 3:00
  disappointed.
• 3:01
  Andrew Dunkley: Yes.
• 3:01
  Jonti Horner: And I think that's the damage in it. It's a
• 3:03
  boy who cried wolf syndrome, right?
• 3:04
  Andrew Dunkley: Yes.
• 3:05
  Jonti Horner: Here's amazing thing. It's going to be
• 3:07
  brighter than the midday sun and, and then
• 3:09
  you can't see it except if you've got a
• 3:11
  telescope. People go, well, why should I have
• 3:12
  a look?
• 3:13
  Andrew Dunkley: Yeah, yeah, absolutely. M. And that's just
• 3:16
  going to get worse. Uh, I don't know how you
• 3:18
  stop it.
• 3:18
  Jonti Horner: I don't.
• 3:19
  Andrew Dunkley: There's too many, too many buff heads out
• 3:22
  there who just want to stir people up.
• 3:23
  Jonti Horner: But, uh, I wonder whether it's going to be
• 3:25
  one of these things that booms and then
• 3:27
  collapses and reaches a stead partially just
• 3:29
  because of the incredible costs involved with
• 3:31
  the AI and you know, the energy use and the
• 3:33
  water use that everybody talks about. I
• 3:36
  wonder if it's going to be a thing that's
• 3:37
  like the, the lady's shiny toy at the minute
• 3:39
  and everybody's using it and then it'll just
• 3:42
  fall by the wayside a little bit, I guess,
• 3:43
  like auto tune and pop music and stuff like
• 3:46
  that. I remember a while where every pop hit
• 3:48
  that turned out on the radio seemed to have
• 3:50
  these weird distortions and it means
• 3:51
  everybody was fond of auto tune. Um, and
• 3:54
  nowadays people would rather prove that they
• 3:56
  can sing themselves rather than have the
• 3:58
  computer do it for them.
• 3:59
  Andrew Dunkley: Yeah. Well, I, uh, remember a radio
• 4:01
  interview, uh, on an entertainment segment
• 4:04
  when I worked for the ABC years ago, probably
• 4:06
  going back 20, 20 odd years or more.
• 4:09
  And the expert in inverted
• 4:12
  commas, uh, was asked if reality television
• 4:15
  had a future and she said, no, it'll phase
• 4:17
  out in five years. Um,
• 4:20
  no, I think it's a
• 4:23
  dominant format now.
• 4:25
  Jonti Horner: Makes my head hurt. But I often say this when
• 4:27
  I'm talking about the search for life
• 4:28
  elsewhere, and the fact that, uh, we're
• 4:30
  betting all our assumptions on knowing one
• 4:31
  form of life, which is Earth. Uh, life, very
• 4:33
  diverse, but only one form of life. There's
• 4:36
  an old saying that I'm probably paraphrasing,
• 4:38
  is that the one prediction you can make with
• 4:40
  certainty, uh, is that all predictions will
• 4:42
  be wrong.
• 4:42
  Andrew Dunkley: Yeah. And that one's right.
• 4:45
  Yes, indeed. Uh, we better get down to
• 4:48
  it.
• 4:48
  And our first story, our first couple of
• 4:51
  stories, in fact, involve SpaceX. They've,
• 4:53
  uh, made the news again with a recent
• 4:55
  touchdown that, uh, has been quite
• 4:57
  spectacular. But they've got bigger and
• 4:59
  bolder plans, which we'll get to shortly. So
• 5:02
  tell us about this. Uh, I watched the video.
• 5:05
  It's quite an amazing feat of engineering,
• 5:07
  isn't it?
• 5:08
  Jonti Horner: It is. And it's a reminder that the
• 5:11
  development of rockets is done through
• 5:13
  explosions. And SpaceX are very aggressive
• 5:15
  with that. And there was a lot of humor hard,
• 5:17
  uh, earlier in the year about the incredibly
• 5:19
  expensive firework displays they were putting
• 5:21
  on for people of the Caribbean, where there
• 5:23
  were three SpaceX test launchers on the trot
• 5:26
  that went boom, um, in what
• 5:28
  SpaceX describe as rapid unscheduled
• 5:31
  disassembly. I love that. Yeah. It apparently
• 5:34
  started as a joke and became a meme and now
• 5:36
  is just a standard term, which is kind of
• 5:38
  adorable in itself. Yeah. And at the
• 5:41
  time, even though there was a bit of fun to
• 5:43
  be had, and there were some concerns as well,
• 5:45
  because debris was found across the Turks and
• 5:47
  Caicos Islands and there was a lot of
• 5:49
  controversy about who owns, um, it, who
• 5:51
  should clean up after it, all the rest of it,
• 5:53
  all the way through, there's this ongoing
• 5:55
  line that this is how they learn, this is how
• 5:58
  you develop rockets, is you test them to
• 6:00
  destruction. And, um, from the destruction
• 6:03
  you learn more than you would do from a
• 6:04
  successful flight. And SpaceX have
• 6:07
  done this all the way through their long
• 6:09
  history and, uh, they've had a much more
• 6:11
  aggressive testing schedule than you'd be
• 6:13
  used to. If you think back to the rocket
• 6:16
  launchers of bygone eras where governments
• 6:18
  were in charge, where every time something
• 6:20
  went wrong, there was this huge delay where
• 6:23
  they were painstaking and trying to figure
• 6:24
  out the nitty gritty and everything about it
• 6:27
  with the way SpaceX have worked. They've got
• 6:29
  the next rocket under construction when they
• 6:31
  launch the current one. So there's this rapid
• 6:33
  turnover, uh, of lots of testing,
• 6:36
  where the goal is not for the next test to
• 6:38
  necessarily be a perfect success, but rather
• 6:41
  to be better than the last one, and what
• 6:44
  we've seen with the last two launches of
• 6:46
  their starship, of their big
• 6:48
  headliner rocket that is destined to be the
• 6:50
  one to launch people to the moon and to Mars
• 6:52
  and beyond, is the benefits of this kind
• 6:55
  of process. We've just seen the fifth
• 6:57
  starship launch of the year and, um, the
• 7:00
  second one which has gone well, and it's the
• 7:03
  final launch, incidentally, of this version
• 7:04
  of starship. They're now working on a bigger
• 7:06
  version that's slightly taller and slightly
• 7:08
  gruntier, which will do some more testing and
• 7:11
  then they'll build an even bigger version,
• 7:13
  which is the one that they hope to do a lot
• 7:15
  of the really exciting stuff with. But the
• 7:18
  current launch, happened about a week ago
• 7:20
  now, was live streamed and, um, there is
• 7:23
  beautiful video footage of it online,
• 7:26
  particularly of the final stages of the
• 7:28
  relatively soft, gentle landing in the ocean.
• 7:31
  And, um, what they achieved with the launch
• 7:33
  was successfully launched. The boosters, I
• 7:36
  believe, on the sides, came back and touched
• 7:37
  down on the pad, which is an incredible
• 7:40
  technical achievement when you think about
• 7:41
  it, and we now almost take it for granted.
• 7:43
  Yeah. And that's part of the achievement that
• 7:45
  has allowed SpaceX to launch things to space
• 7:47
  much more cheaply than those previous
• 7:49
  government missions I mentioned, because you
• 7:51
  can reuse parts and that lowers the cost
• 7:53
  dramatically. But then the main body of the
• 7:55
  starship did this suborbital flight,
• 7:57
  probably, in all honesty, delayed some Qantas
• 8:00
  passengers flying from Australia to South
• 8:01
  Africa because they say we're going to launch
• 8:04
  a rocket and of course you don't want an
• 8:06
  aircraft to be the way when it's coming back
• 8:07
  down. And there were a lot of stories about
• 8:10
  that earlier in the year with disgruntled
• 8:11
  Qantas passengers being delayed when
• 8:13
  launchers were scrubbed. So their flight was
• 8:15
  delayed and the launch didn't even happen.
• 8:17
  This launch definitely did. It flew
• 8:20
  this suborbital flight, did a few test
• 8:22
  deployments of satellites to prove it could
• 8:24
  do that, then reentered the atmosphere. And
• 8:26
  there's this gorgeous footage of the thing
• 8:29
  falling sidewards through the atmosphere, not
• 8:31
  out of control, not tumbling, but looking
• 8:33
  like it's coming in sideways and like
• 8:34
  everything's done and it's just going to
• 8:36
  crash. And, um, then suddenly the engines
• 8:39
  turn on and it stands on its tail and just
• 8:40
  slows down and slows down until it kicks up
• 8:43
  all this steam, all this water, but
• 8:44
  essentially just gently settles onto the
• 8:46
  water and has a soft landing where it can be
• 8:49
  recovered and reused. And that soft landing
• 8:52
  happens somewhere to the west of Western
• 8:54
  Australia in the Indian Ocean. And
• 8:56
  it's a really incredible technical feat. Uh,
• 8:59
  I will bag SpaceX when we're talking about
• 9:02
  Starlink. While I acknowledge that that does
• 9:04
  a lot of good as well, it's one of these
• 9:05
  things where it's not all good, it's not all
• 9:07
  bad, but there's aspects of both. But I think
• 9:10
  this kind of success should be really
• 9:12
  celebrated because it's a really fabulous
• 9:15
  example of this constant progression of
• 9:17
  improving technology we're getting that will
• 9:19
  make human use of space cheaper in
• 9:22
  the future. It'll allow a lot more variety in
• 9:24
  what we do. And the context here, of course,
• 9:27
  is that SpaceX have a contract with NASA to
• 9:29
  launch astronauts to the moon. And the
• 9:32
  accelerator plan for that is that the Artemis
• 9:34
  3 mission is scheduled to launch in early
• 9:36
  2027 to send people out to the
• 9:39
  moon to do a lap of the moon and bring them
• 9:40
  back and probably spend even up to 30 days in
• 9:42
  space, quite a lengthy mission that will be
• 9:45
  launched off the next generation of this
• 9:48
  starship, or the next, but one generation of
• 9:50
  this starship. And uh, the fact that they've
• 9:52
  now had two launches on the track where it
• 9:54
  all worked, uh, and nothing blew up is
• 9:55
  probably fairly reassuring for the people who
• 9:57
  plan to sit on top of this thing in 12 or 18
• 10:00
  months time. It's also something where
• 10:03
  there's a bit of extra pressure from the big,
• 10:04
  big head guy who didn't develop the company
• 10:07
  but bought it and has been a good advocate
• 10:09
  for it, I think you'd possibly say in the
• 10:10
  form of Elon Musk, challenging individual,
• 10:13
  but he's really very vocal about the
• 10:16
  fact that he wants this thing to not just
• 10:17
  send people to the moon, but also to send
• 10:19
  them to Mars. Yes. And uh, one of the things
• 10:21
  he wants to achieve in the tech demonstrator
• 10:23
  phase of that is to use
• 10:26
  Starship version 3, which is a version
• 10:29
  after the next version, to launch a mission
• 10:32
  to Mars, sending small
• 10:34
  spacecraft robots effectively in the next
• 10:37
  launch window to Mars. Now that next launch
• 10:39
  window is only 12 months away. For those who
• 10:41
  are keen at looking at the night sky, Mars is
• 10:43
  almost now hidden behind the sun. It's pretty
• 10:45
  much out of view. We're swinging back around
• 10:48
  to gradually approach it again. And by this
• 10:49
  time next year we'll see the usual flurry
• 10:52
  of activity as people start to launch their
• 10:55
  spacecraft. And you get the next wave of
• 10:57
  things going to Mars because that's a cheap
• 10:58
  and quick time to go there. That's the launch
• 11:01
  window. Uh, and Elon Musk wants version three
• 11:03
  of starship ready so that
• 11:06
  it can launch things to Mars in that launch
• 11:09
  window, uh, to demonstrate the capacity of
• 11:11
  getting things there with a rocket big enough
• 11:13
  to eventually put people there. And of
• 11:15
  course, he's famously expressed the desire to
• 11:17
  be the first person to die on Mars. Um, I'm
• 11:19
  sure many people in the audience have similar
• 11:21
  aspirations for Elon Musk.
• 11:24
  Andrew Dunkley: Um, we've had a few comments over the course
• 11:27
  of the last several months.
• 11:29
  Jonti Horner: Absolutely. But this is where things are
• 11:31
  looking. And the fact that they've been so
• 11:33
  successful so quickly is really promising for
• 11:35
  the moon missions and, um, for the Mars
• 11:37
  missions to come down. The future, and it
• 11:38
  should be celebrated. And the footage that's
• 11:41
  out there that you can find all over the
• 11:42
  place on YouTube Music is really
• 11:44
  astonishingly incredible. To see the control
• 11:47
  this rocket has and the fact that coming back
• 11:49
  through the atmosphere, falling on its side,
• 11:51
  it can suddenly just wake up, stand on its
• 11:53
  tail and gently touch down in the water.
• 11:55
  That's really cool.
• 11:57
  Andrew Dunkley: It is very, very cool. It sort of goes back
• 11:59
  to the early days of science, uh,
• 12:02
  fiction, where that's what rockets did.
• 12:04
  Jonti Horner: Yes.
• 12:05
  Andrew Dunkley: And now it's real. Uh, so much stuff seems to
• 12:08
  be happening that, uh, has been written about
• 12:10
  by science fiction writers, you know,
• 12:13
  50, 100 years ago. Um, so this,
• 12:16
  this new version of the, um,
• 12:19
  uh, the spaceship is going to
• 12:22
  be, as you said, bigger, uh, and
• 12:25
  gruntier. It's going to have some really, um,
• 12:27
  powerful Raptor engines attached to it, and
• 12:29
  it'll be quite an awesome piece of machinery.
• 12:32
  Biggest rocket ever, I think.
• 12:34
  Jonti Horner: Absolutely. And it would not surprise me if
• 12:37
  there were a few explosive disassemblies of
• 12:39
  this one as they're tuning up, because that's
• 12:41
  how they learn. And I think there were a lot
• 12:43
  of people who are not tuned into this, who
• 12:45
  are not quite as big as space fans as we all,
• 12:48
  uh, are, who, when the explosions were
• 12:50
  happening, were taking a lot of mirth from it
• 12:52
  and saying, come on, I can't even launch a
• 12:54
  rocket. And we've been doing it for 50 years.
• 12:56
  And a lot of the voices on the Internet who
• 12:58
  follow how these things go, who are much
• 13:00
  wiser and much more knowledgeable about this
• 13:02
  than I am, were saying, don't panic. This is
• 13:04
  exactly how SpaceX do business. They're not
• 13:06
  worried. This is how they learn. And each
• 13:09
  failure happened later, and now they get
• 13:11
  successes. It's how they work, and it's how
• 13:13
  you learn. You learn more from your failures
• 13:14
  than the success.
• 13:15
  Andrew Dunkley: Yes, they could well be sending a fleet of
• 13:18
  these Starship V3s to Mars next year,
• 13:21
  the way they're talking. So watch, watch
• 13:23
  this. SpaceX boom, boom.
• 13:25
  Uh, let's move on to our next story.
• 13:28
  Uh, this is one that your university's uh, a,
• 13:31
  uh, little involved in. And this is low cost
• 13:34
  private space telescopes. Do tell.
• 13:38
  Jonti Horner: I do love this. Now I can immediately take a
• 13:40
  total detour here, um, because I'm good at
• 13:42
  that. Here's a topic and I'm not going to
• 13:44
  talk about it for the first few minutes, but
• 13:46
  we have at UNISQ something I'm really proud
• 13:49
  of, which is our Minerva Australis facility.
• 13:51
  And um, that is something we've built to find
• 13:54
  planets around other stars and learn more
• 13:55
  about them to basically work following
• 13:58
  up the observations of the NASA TESS mission.
• 14:01
  Uh, and we were able to build this facility
• 14:03
  which is the only professional astronomical
• 14:05
  research observatory in Queensland, using
• 14:08
  Australian Research Council funding and using
• 14:10
  input from partner universities. And
• 14:13
  we're talking about a total budget here of a
• 14:16
  few million Australian dollars, less than 10
• 14:18
  million. If you went back even
• 14:20
  20 years this would not have been possible.
• 14:23
  What we've been able to do is build this
• 14:25
  array of telescopes where all the telescopes
• 14:26
  have 70 centimeter mirrors. So they're big
• 14:29
  chunky research grade telescopes that we were
• 14:31
  able to buy off the shelf because there's a
• 14:33
  company called Plane Wave who
• 14:36
  developed what is essentially the Model T
• 14:38
  Ford revolution for research level
• 14:41
  telescopes where they realized that there's a
• 14:43
  really big market for telescopes that are big
• 14:46
  compared to what amateurs use, but at the
• 14:48
  small end of what professional astronomers
• 14:50
  use. And uh, there's a big market because the
• 14:52
  military wants these to be looking for space
• 14:54
  debris and to do space situational awareness,
• 14:58
  satellite tracking, things like that. The
• 15:00
  wealthiest of the amateur astronomy community
• 15:02
  want these to do their astronomy with and uh,
• 15:04
  the professional astronomers would want to
• 15:06
  use them as well. And um, by
• 15:09
  setting up a production line where you
• 15:11
  produce these things relatively en masse,
• 15:14
  rather than getting an order for a telescope,
• 15:16
  designing a specific telescope for that
• 15:18
  telescope's needs and building it as a one
• 15:21
  off, you can build things on a production
• 15:24
  line and you can make them a lot cheaper. In
• 15:26
  this case about an order of magnitude
• 15:28
  cheaper. Uh, so that meant we were able to
• 15:30
  get these telescopes of this size and of this
• 15:32
  quality for about a quarter of a million
• 15:33
  dollars each instead of two and a half
• 15:36
  million dollars each. Wow. Which meant that
• 15:38
  we were able to build this facility and build
• 15:40
  a relatively low cost research facility
• 15:43
  for one task. And that's in real contrast
• 15:46
  to uh, most of the really big expensive
• 15:48
  observatories historically which have been
• 15:51
  really expensive and all singing, all
• 15:53
  dancing, to do all things for all people.
• 15:55
  By having this kind of Model T Ford
• 15:57
  revolution where you suddenly have telescopes
• 15:59
  coming off a production line, you're able to
• 16:02
  make things in order of magnitude more
• 16:03
  affordable. And that allows people to be
• 16:06
  innovative and develop bespoke
• 16:09
  observatories that do one thing well rather
• 16:10
  than everything well. And they can do that a
• 16:12
  lot cheaper. And that's been a huge success
• 16:15
  for us. We've discovered about 40 or 50
• 16:18
  planets. We've been involved in the
• 16:19
  discoveries all at a really low cost, which
• 16:22
  makes this probably the cheapest exoplanet
• 16:24
  facility on the planet in terms of cost per
• 16:27
  planet. Learned about. So we're really proud
• 16:29
  of that. And working on that,
• 16:32
  we learned about a company in the UK
• 16:35
  called Blue Sky Space limited And they are
• 16:38
  a very innovative, innovative spin out
• 16:40
  from, um, University of
• 16:43
  London, um, and my name is Dun Turtle Black
• 16:46
  there. It's not the Royal Holloway University
• 16:47
  of London, but it's one of the big
• 16:49
  universities in the middle of London. We've
• 16:51
  worked with them closely. We've had Giovanna
• 16:54
  Tinetti, who's one of the world's leading
• 16:55
  scientists from them, visit us on a couple
• 16:57
  occasions. And uh, there's this spin out that
• 16:59
  came out of their undergraduate master's
• 17:02
  program where people have set up a company
• 17:05
  that has looked at the idea of building
• 17:08
  things on a production line and said, can we
• 17:10
  apply that to space telescopes
• 17:13
  instead of looking at building James Webb,
• 17:15
  which is billions of dollars for an enormous,
• 17:18
  really complex thing that everybody has to
• 17:19
  fight to use? Yeah. Can we take the
• 17:22
  parts that are available to us off the shelf
• 17:25
  from people making satellites and
• 17:27
  particularly making things like cubesats,
• 17:29
  which are designed to be easy to put
• 17:31
  together, cheap to put together because you
• 17:32
  can go and get pieces off a shelf. And can we
• 17:35
  effectively crowdsource from research
• 17:37
  institutions cheaper, more
• 17:39
  specialized space telescopes that are
• 17:42
  built off the shelf and um, reduce the costs
• 17:45
  of building space telescopes by a factor of
• 17:48
  10 to 100 times. The first of
• 17:50
  these that they came up with is a project
• 17:52
  called twinkl that I know for a fact where
• 17:54
  one of the universities that's bought in on
• 17:56
  and that's going to launch a telescope with
• 17:59
  about a 70 centimeter mirror, so comparable
• 18:01
  to the ones we've got at our facility for a
• 18:04
  cost of about $75 million, or
• 18:07
  there's a real exoplanet tool. Now $75
• 18:10
  million sounds expensive, but to
• 18:13
  launch a space telescope of that kind of
• 18:15
  caliber for $75 million is utterly unheard
• 18:18
  of. And the way they're doing it is by
• 18:19
  building it from off shelf materials, they're
• 18:22
  getting universities to buy it and those
• 18:23
  universities get guaranteed access and they
• 18:26
  get to participate in the design. So you get
• 18:28
  the telescope that is good for the science
• 18:30
  you want to do. That's going to be Twinkl.
• 18:32
  And Twinkl is going to launch ah, at some
• 18:34
  point in the next couple of years. But
• 18:36
  they've also been working on what was
• 18:39
  developed second but will launch first,
• 18:42
  which is a smaller, even cheaper
• 18:45
  instrument called mawv. Now we've
• 18:48
  been involved in the discussions with this
• 18:50
  since it was first a thing. But I don't off
• 18:52
  the top of my head know whether we've got buy
• 18:54
  in or whether we're observers on the
• 18:56
  sideline, sharing them in because I'm not
• 18:58
  personally involved with the mission. But
• 19:01
  Mauv is a CubeSat. It's going to be about
• 19:03
  the size of a small briefcase. It has got
• 19:06
  an off the shelf UV instrument
• 19:09
  so ultraviolet looking at wavelengths shorter
• 19:12
  than we see with the unaided eye that they've
• 19:15
  been able to modify to allow it to be a
• 19:17
  spacecraft that is dedicated at studying
• 19:20
  stellar flares, looking at stars, stars
• 19:23
  like the sun, stars like red dwarfs like
• 19:25
  Proxima Centauri and studying them to look at
• 19:28
  how active they are, learning more about
• 19:29
  their activity levels. Now this is really
• 19:31
  interesting in the context of exoplanets, ah,
• 19:34
  and the search for life elsewhere. That's one
• 19:37
  of the big motivators of this because this
• 19:39
  idea that stellar flares and stellar activity
• 19:43
  could be something that makes a planet that
• 19:44
  would otherwise be really suitable for the
• 19:46
  search for life and suitable for life to
• 19:48
  develop and thrive and turn that planet into
• 19:50
  a barren and hostile wasteland. And Mars
• 19:53
  is held up as an example of this. Mars has a
• 19:56
  very thin and tenuous atmosphere now. It's
• 19:58
  cold and arid, but when it was young it was
• 20:00
  warm and wet and had oceans and would
• 20:03
  have looked almost like a mini version of
• 20:05
  Earth, uh, 2.0. It had all the conditions you
• 20:07
  need for life. But over billions of years,
• 20:09
  Mars's atmosphere has been whittled away from
• 20:12
  the outside in by solar activity, in part
• 20:15
  because Mars doesn't really have a strong
• 20:16
  magnetic field now it's also lost the
• 20:18
  atmosphere chemically to the surface. But
• 20:21
  this has always given people an idea that
• 20:23
  stellar activity constrict the atmospheres of
• 20:25
  planets and render them unsuitable for life
• 20:27
  in the long term as well as in the shorter
• 20:30
  term. That extreme activity would lead to UV
• 20:33
  doses that could even break through and
• 20:35
  sterilize the planet. So there's a lot of
• 20:36
  ways stellar activity could be bad for life.
• 20:40
  What we know about with the sun is the sun's
• 20:42
  a really calm and chill star. It's much less
• 20:44
  active than the majority of stars are. And
• 20:47
  that has led to people speculating along the
• 20:50
  lines of the anthropic principle that we're
• 20:53
  only here to observe the universe because our
• 20:56
  sun is so stable, and therefore we should
• 20:59
  only ever look at stars that are really,
• 21:00
  really stable. There are others who argue
• 21:02
  that you can't take every coincidence about
• 21:05
  our solar system and assume that it's a
• 21:07
  requirement for life. And, uh, maybe it is
• 21:09
  just coincidence that we happen to be around
• 21:11
  a really stable star. But if we want to learn
• 21:13
  more about planetary systems around other
• 21:15
  stars, and particularly if we want to be able
• 21:17
  to focus the search for life elsewhere, on
• 21:20
  the planets that are the most promising
• 21:21
  targets, we want to maximize the chances of
• 21:24
  those planets having life and being suitable
• 21:26
  for life. It's really important to learn as
• 21:28
  much as we can about the star, the planets
• 21:30
  themselves, all that kind of stuff. And
• 21:32
  that's where Morph comes in. Morph is
• 21:35
  ridiculously cheap for a space telescope, to
• 21:37
  be honest, because it's one of these cubesats
• 21:39
  made from off the shelf materials. It's got
• 21:41
  this off the shelf UV detector that's been
• 21:43
  modified to do stellar activity work. And
• 21:46
  it's going to launch potentially in the next
• 21:49
  month, possibly as soon as that. Really,
• 21:51
  really exciting. And what it will be doing is
• 21:53
  looking at stars and studying their stellar
• 21:56
  flares, studying their activity to give us a
• 21:58
  really good handle on the diversity of
• 22:00
  stellar activity you get from planet hosting
• 22:02
  stars. And to start teaching us about
• 22:06
  how those flares could interact with the
• 22:08
  planets that those stars host. Ties into
• 22:11
  theoretical work that colleagues of mine at
• 22:12
  UNESQ have been doing for years, using
• 22:16
  the kind of modeling software that people use
• 22:18
  to model space weather in the solar system
• 22:19
  and trying to apply that to stars that are
• 22:22
  not the sun and planets around them. This
• 22:25
  will give the observational grounding for
• 22:27
  that theoretical work so that people can get
• 22:29
  a much better handle on whether this
• 22:32
  assumption we've got based on the one
• 22:33
  planetary system we have is actually worth
• 22:36
  following, Whether it's less important than
• 22:38
  that, whether it's more important than that.
• 22:40
  And so we're going to learn a hell of a lot
• 22:42
  about stars and also habitability, and help
• 22:45
  direct our search for the most promising
• 22:47
  targets for the search for life, all from a
• 22:50
  company that's just innovatively saying
• 22:52
  instead of trying to build James Webb at
• 22:54
  incredible cost and having astronomers from
• 22:56
  all disciplines fighting for it. Let's build
• 22:59
  something off the shelf with much cheaper
• 23:01
  components at a much lower price.
• 23:03
  Build it in such a way that it's good at one
• 23:05
  thing rather than being good at everything.
• 23:07
  It's good at one thing and one thing only.
• 23:09
  And, uh, yet there are people who want to do
• 23:11
  that one thing to contribute to the cost of
• 23:13
  launching it. And it is like a space
• 23:16
  version of what we've done with Minerva
• 23:17
  Australis. And we know with our facility just
• 23:20
  how successful that model can be. We've
• 23:22
  really pushed above our weight because we've
• 23:23
  been able to do that. And Mauve and, um,
• 23:26
  Twinkl, which will follow, are a really
• 23:28
  interesting window to a future where instead
• 23:30
  of everybody fighting for Hubble or everybody
• 23:33
  fighting for Spitzer or James Webb,
• 23:36
  different research teams have smaller,
• 23:38
  cheaper instruments dedicated to the work
• 23:40
  they want to do. And science advances that
• 23:43
  way instead. There'll still obviously be a
• 23:46
  place for James Webb and telescopes like
• 23:47
  that. They will do things that you could not
• 23:49
  do with an instrument this small. But what
• 23:52
  this will also do is it will mean that
• 23:53
  there's a little bit less competition for
• 23:55
  those jack of all trades facilities, because
• 23:58
  people who want to do a specific thing may
• 24:00
  have another option that is cheaper and
• 24:01
  easier for them to get time on and reduces
• 24:04
  their contribution to the burden on the other
• 24:06
  scopes. So this will doubtless indirectly
• 24:08
  benefit people doing very different science
• 24:11
  because they get more time to do their
• 24:13
  science because their competitors are getting
• 24:15
  time on telescopes in other ways.
• 24:17
  Andrew Dunkley: Yeah.
• 24:17
  Jonti Horner: Could this just open for many, many different
• 24:19
  reasons? Yeah.
• 24:20
  Andrew Dunkley: Could this lead to, um, total
• 24:23
  rethink of how, um, space
• 24:26
  telescopes operate? Like, could, uh, there
• 24:28
  be a group that says, okay, we want to
• 24:31
  specifically search for
• 24:34
  X in space. Uh, we need a
• 24:37
  specific kind of telescope to do that. If
• 24:40
  you build it, we will come, send it into
• 24:42
  space and we can do our job.
• 24:44
  Could it lead to that kind of thing?
• 24:46
  Jonti Horner: I think so long as the price is right.
• 24:49
  Um, and that's the thing. If this was no
• 24:51
  cheaper than building James Webb, nobody'd be
• 24:53
  interested. But Twinkle will be a fairly big
• 24:56
  space telescope. You know, 70 centimeter
• 24:58
  mirror is not to be sniffed at. That's a
• 25:00
  fairly chunky piece of kit. To build
• 25:02
  something like that at, uh, a cost. That is
• 25:05
  what I said, about $75 million when
• 25:08
  James Webb was more than $10
• 25:10
  billion. That is a factor of
• 25:13
  100 difference in price, effectively,
• 25:16
  something like that. Now, 100 twinkls would
• 25:18
  not be able to do the Same science that one
• 25:21
  James Webb does. But 100 Twinkls could do a
• 25:24
  lot of very diverse science. And so
• 25:27
  it achieves different things. Now
• 25:29
  there are other things out there. We've got
• 25:31
  an interesting one in that there is a
• 25:33
  partnership between my university unesq,
• 25:36
  through this iLaunch initiative that's an
• 25:38
  Australian thing, with the University of
• 25:40
  South Australia, with Optus, with the
• 25:43
  Australian National University and with a
• 25:45
  couple of startup companies in South
• 25:46
  Australia where there is an Australian
• 25:49
  sovereign satellite that is in the
• 25:51
  construction under what's called Project
• 25:52
  Swift. And uh, this is going to be about a
• 25:55
  $50 million project. And um,
• 25:58
  that is going to be a satellite where Optus
• 26:00
  are interested because they're going to be
• 26:01
  testing technology for better
• 26:02
  telecommunications and also
• 26:05
  telecommunications platform that are
• 26:06
  Australian owned for Australian citizens. So
• 26:08
  you're not at the whim of people from other
• 26:10
  countries who may have the ability to turn
• 26:13
  off your network as we saw with Elon Musk
• 26:15
  turning off Starlink over Ukraine at one
• 26:17
  point because he wanted to. We are
• 26:20
  concerned about that. So, uh, Optus are
• 26:22
  thinking, well, let's try and have an
• 26:23
  Australian communications platform. Our
• 26:26
  involvement is if you've got a satellite
• 26:28
  going around the Earth looking down the
• 26:30
  backside of that satellite's looking out to
• 26:32
  space. What if you put a space telescope on
• 26:35
  the other side of the satellite? You can have
• 26:36
  a satellite that's doing telecoms in one
• 26:38
  direction whilst also providing research
• 26:40
  capacity in the other. So UNISQ is leading
• 26:43
  the research telescope side of that and my
• 26:45
  colleague Duncan Wright, who's leading the
• 26:46
  centre of our, who's the head of our center
• 26:48
  of Astrophysics here, is heavily involved in
• 26:51
  putting together this innovative, fairly
• 26:52
  small 20 centimeter TACT telescope to do a
• 26:55
  little bit of exoplanet work off the back of
• 26:58
  a commercial platform designed for something
• 26:59
  else. And that's a really interesting
• 27:01
  partnership. Now that is Ben. It all
• 27:04
  ties back to the commercial launch capacity
• 27:06
  that SpaceX have provided. Suddenly
• 27:09
  you've lowered the price of our access to
• 27:11
  space to such a level that people can now be
• 27:14
  really innovative and think of new solutions.
• 27:17
  Andrew Dunkley: Love it.
• 27:18
  Jonti Horner: The downside is more satellites, more light
• 27:20
  pollution. The upside may be more cool
• 27:22
  research.
• 27:23
  Andrew Dunkley: Yeah, um, there's a price to pay for
• 27:25
  everything, I suppose.
• 27:26
  Jonti Horner: Yeah.
• 27:26
  Andrew Dunkley: Okay, keep uh, an eye out for that and watch
• 27:29
  out for Twinkl, uh, launching soon.
• 27:32
  This is Space Nuts with Andrew Dunkley and
• 27:35
  Professor Jonti Horner.
• 27:40
  Jonti Horner: Three, two, one. Space
• 27:43
  Nuts.
• 27:43
  Andrew Dunkley: Okay, moving out into the realm of
• 27:46
  exoplanets as we've been discussing. Uh, and
• 27:49
  another weird one has been found. Uh, we
• 27:52
  found one similar to this, but uh, this one's
• 27:55
  a little bit different because it's not where
• 27:57
  you might.
• 27:57
  Jonti Horner: Expect it to be. Yes,
• 28:00
  one of the things that we can do when we're
• 28:02
  finding plants under the stars is we can
• 28:04
  learn more about them if we can study them
• 28:06
  with more than one technique. So going back
• 28:08
  to the real basics, the two most successful
• 28:11
  ways of finding planets around the stars are
• 28:14
  the radial velocity method and the transit
• 28:16
  method. And uh, the radial velocity method is
• 28:18
  where you see a star wobbling towards or away
• 28:20
  from us. Using the Doppler effect, the size
• 28:23
  of that wobble tells you the mass of the
• 28:26
  planet roughly, although we don't really know
• 28:28
  the tilt of the orbit. So it gives us a
• 28:29
  minimum mass for that planet. The bigger the
• 28:32
  planet is for a given wobble period, a given
• 28:34
  orbital period, well rather the more massive
• 28:37
  a planet is, the bigger the wobble will be.
• 28:40
  So that gives us about the mass of the
• 28:41
  planet, but it doesn't tell us anything about
• 28:43
  its diameter. So you can't tell whether it's
• 28:46
  a Jupiter mass ball of iron or a Jupiter mass
• 28:48
  ball of feathers. They'd have the same
• 28:50
  gravitational pull, the same effect on the
• 28:51
  wobble. Then you have the transit technique,
• 28:54
  which is where, ah, you have
• 28:57
  a planet going in front of a star from our
• 28:59
  point of view and blocking some of the light.
• 29:01
  And um, the bigger the planet's diameter, the
• 29:04
  more light it will block. So this doesn't
• 29:06
  tell you anything about the mass of the
• 29:08
  planet. It could be a Jupiter
• 29:11
  diameter ball of feathers or a Jupiter
• 29:13
  diameter ball of iron. It would block the
• 29:15
  same amount of light, but it does tell you
• 29:17
  about the size, the diameter. If you
• 29:20
  can do both of those methods for the same
• 29:22
  object, you can get the mass and um, you can
• 29:24
  get the size, which means you can get the
• 29:26
  density. And that's allowed us to
• 29:29
  identify that planets have a much,
• 29:32
  much, much greater diversity
• 29:36
  of densities and compositions than you'd ever
• 29:38
  have imagined best. Solely on the solar
• 29:40
  system, we found planets that are less dense
• 29:42
  than cotton candy. We found planets. There's
• 29:45
  one peculiar one that is so much denser than
• 29:48
  osmium that people think it is actually not a
• 29:51
  planet at all, but it's actually a planet
• 29:52
  sized fragment of a white dwarf that was
• 29:55
  smashed into pieces. I mean, how weird is
• 29:57
  that?
• 29:57
  Andrew Dunkley: That is weird.
• 29:58
  Jonti Horner: So something the size of the Earth, uh, but
• 30:00
  150 times the density of water, which
• 30:03
  breaks physics.
• 30:04
  Andrew Dunkley: Yeah.
• 30:04
  Jonti Horner: You know, we find all these things and the
• 30:06
  only way we can tell that is because we can
• 30:08
  measure the mass of the size, the planet that
• 30:10
  we're talking about here, which is TOI
• 30:13
  4507B. And what that
• 30:16
  barcode means is it's test object of
• 30:17
  interest. It's the catalog. It's TESS
• 30:20
  thinks there is a planet around this star.
• 30:23
  This is the 4507th
• 30:25
  object listed in the catalog of Tess thinks
• 30:28
  this could be a planet. And the B means this
• 30:30
  is the first planet found around that star.
• 30:33
  That's what the bar curve means. And the team
• 30:35
  that has announced the discovery of this
• 30:37
  planet have done some work using a
• 30:40
  variety of instruments. They've used NASA's
• 30:42
  test mission, they've used some telescopes
• 30:44
  based in Antarctica. And it's allowed them to
• 30:46
  do radial velocity observations to measure
• 30:49
  the size. And it's allowed them to do transit
• 30:51
  observations to confirm the diameter. So
• 30:54
  we've got the mass and the diameter. And that
• 30:56
  has shown that this is a planet that is
• 30:59
  about the size of Saturn, about the diameter
• 31:02
  of Saturn, but a third of Saturn's mass. It's
• 31:05
  only 30 earth masses, but it's nine
• 31:08
  times the earth's diameter. And, uh, that
• 31:10
  means the density of this thing is really
• 31:12
  low. The density is less than 0.3
• 31:15
  grams per cubic centimeter. It's less than
• 31:17
  30% the density of water, which
• 31:20
  is really fluffy. That's really, really low
• 31:23
  density. And, um, that means that in the
• 31:25
  standard parlance that people have accepted
• 31:27
  these days, this is classified as a super
• 31:30
  puff planet because it's all puffed up and
• 31:32
  light and fluffy and very distended.
• 31:36
  Now we think we understand how superpuffed
• 31:38
  planets form. In the main, they're planets
• 31:41
  that are usually very close to very young,
• 31:43
  hot stars, often moving on orbits that are
• 31:46
  not perfectly circular. And so what's
• 31:49
  happening is that these planets formed
• 31:51
  further from their stars. They were flung
• 31:53
  inwards, probably through interactions with
• 31:55
  other planets, initially on quite an
• 31:57
  eccentric orbit. And they're undergoing what
• 31:59
  we call tidal circularization.
• 32:03
  So their orbit was extremely elongated, but
• 32:06
  they feel very strong tides when they're near
• 32:08
  their closest point to the star and much
• 32:10
  weaker tides when they're further away. And
• 32:12
  those tidal effects are acting to make the
• 32:13
  orbit more and more circular by essentially
• 32:16
  pulling down that point where the planet is
• 32:18
  furthest from the star and dragging that
• 32:19
  inwards. Now, that circularises the
• 32:22
  orbit, but it also dumps an enormous amount
• 32:24
  of heat into the interior of the planet,
• 32:27
  which makes it puff up. The gas gets hotter,
• 32:29
  so the planet becomes very distended. And in
• 32:32
  many cases, this makes a planet so large that
• 32:34
  the outer atmosphere is getting stripped
• 32:36
  away. And I know a colleague and man at
• 32:38
  UNESCU have done studies of some planets like
• 32:40
  this using James Webb, and shown that those
• 32:42
  planets have tails like comets do, because
• 32:45
  the outer atmosphere is blown away by the
• 32:47
  stellar wind. And uh, they've got an enormous
• 32:49
  spectacular tail. So in many ways you can
• 32:51
  think of these as the biggest comets in the
• 32:53
  universe. Most of these
• 32:55
  planets though we know, are really close into
• 32:58
  their stars. And uh, the strength of tidal
• 33:01
  heating is a really strong function
• 33:03
  of distance. It's not just this one over
• 33:06
  distance squared, it's something like one
• 33:08
  over distance cubed or one over distance to
• 33:09
  the power four. So that means if you move a
• 33:12
  little bit further away, the influence of
• 33:14
  tidal heating falls off very, very, very
• 33:16
  rapidly. So we normally expect to only find
• 33:19
  these superpuff planets really close in
• 33:21
  stars. This one is one of the most
• 33:24
  distant superpuffs ever found from its host
• 33:26
  star. It's orbiting an F type star. So that's
• 33:28
  a star a bit hotter, a bit brighter, a bit
• 33:30
  more massive than the sun. But it goes around
• 33:32
  that star every 107 days, which
• 33:35
  means that it is further from that star than
• 33:38
  Mercury is from the sun. And that should be
• 33:41
  too far away really to have significant tidal
• 33:43
  heating going on to make this planet bigger.
• 33:46
  So that's problem number one. That's a little
• 33:48
  bit weird. The other thing that's very weird
• 33:50
  of this is that during the process of doing
• 33:52
  the transit observations of this
• 33:55
  planet, they also did some Rossiter McLachlan
• 33:58
  observations. Now this is a really quirky but
• 34:00
  very beautiful thing that you can do
• 34:03
  with binary stars and with exoplanets.
• 34:05
  Andrew Dunkley: Yeah.
• 34:06
  Jonti Horner: Now with radial velocity, we're measuring the
• 34:08
  star wobbling towards and away from us. But
• 34:10
  that star itself is rotating and young stars
• 34:13
  rotate quicker. So if you imagine that star,
• 34:16
  one side of that star is coming towards us,
• 34:18
  and so the light from that side of the star
• 34:20
  will be blue shifted. The other side of the
• 34:22
  star is rotating away from us and that side
• 34:24
  will be red shifted. And um, what that means
• 34:26
  in actuality is that each spectral line from
• 34:28
  that star is not a perfectly thin line, but
• 34:31
  it's actually quite broad. Some of the light
• 34:33
  is bluer, some of it's redder. So you get
• 34:35
  this chunky, broad spectral line. And I
• 34:37
  appreciate for people listening, you can't
• 34:38
  see me cupping my hands, but I'm waving
• 34:40
  around helpfully in front of the camera here,
• 34:42
  even though you can't see me. So the
• 34:45
  stars rotating and the stars rotation speed
• 34:47
  is really much, much greater
• 34:51
  than the scale of the wobble you get from a
• 34:53
  planet going around that star, if that
• 34:56
  makes sense, the planet going around the star
• 34:58
  makes a wobble measured in meters per second.
• 35:00
  The rotational velocity of the stars measured
• 35:02
  in kilometers per second. When you've got the
• 35:05
  planet going around that star, if it is
• 35:07
  blocking part of the light from that
• 35:10
  star, it will be blocking light from one of
• 35:13
  the two sides of the star that is either
• 35:15
  coming towards you or away from you. So it's
• 35:18
  blocking light that is either blue shifted or
• 35:20
  redshifted. So if you measure the position of
• 35:23
  the spectral lines from that star while the
• 35:25
  planet's in transit, if it's blocking some of
• 35:28
  the blue shifted light, then it will look
• 35:29
  like the light from the star gets redshifted
• 35:32
  by several kilometers a second because you're
• 35:34
  only seeing the red shifted light or you're
• 35:36
  seeing more of the red shifted light. And as
• 35:38
  the planet moves across, it will then block
• 35:39
  the other side of the star and the star's
• 35:41
  light will appear to suddenly become
• 35:42
  redshifted. What this allows you to
• 35:45
  do, it's really intricate and there's some
• 35:47
  lovely video explainers on the web. If it's
• 35:49
  making your head hurt trying to understand
• 35:50
  me, talk through it, there's some really good
• 35:52
  visual explainers out there. But what this
• 35:55
  allows you to do is if you measure the radial
• 35:57
  velocity of a star during the transit of a
• 35:59
  planet, it allows you to work out the tilt
• 36:02
  of that planet's orbit relative to the
• 36:05
  plane of the star's equator. So if the star
• 36:07
  is perfectly above the equator, the planet is
• 36:10
  perfectly above the equator of the star and
• 36:12
  going in the same direction as the star. As
• 36:14
  it comes round, it will first block the side
• 36:16
  of the star that is blue shifted that is
• 36:18
  coming towards us. So the stars light will
• 36:20
  get redshifted, then it'll move across and
• 36:22
  block the red shifted light, and the star's
• 36:24
  light will be blue shifted. Then the transit
• 36:26
  will end and you'll be back to where you
• 36:27
  started from. So you get this weird kind of
• 36:29
  sine wave type shape.
• 36:30
  If the planet's going around backward, that
• 36:33
  will happen in the opposite order. If the
• 36:35
  planet's orbit's really highly tilted, you'll
• 36:38
  make the roster McLachlan effect
• 36:40
  measurements. And um, you'll only get one or
• 36:42
  the other effect, or you might get no effect
• 36:44
  at all because it's coming down vertically
• 36:47
  and always blocking the same side of the
• 36:49
  star.
• 36:49
  Andrew Dunkley: Yep.
• 36:50
  Jonti Horner: So what this means is that you can use this
• 36:52
  technique to measure the tilt of a
• 36:54
  planet's orbit around its star. And again
• 36:57
  We've used that fairly effectively from Mount
• 36:59
  Kent with our wonderful facility we've got
• 37:01
  here. It's become a really common tool in the
• 37:03
  arsenal of planetary scientists. And it's
• 37:06
  revealed a lot of quirky things. So, uh,
• 37:07
  planets around stars like the sun or planets
• 37:09
  around stars that are cooler than the sun
• 37:11
  typically tend to be aligned above the
• 37:14
  equators of the stars going around progrades.
• 37:16
  But when you get to these really hot stars
• 37:19
  that are more massive than the sun, there's a
• 37:21
  growing population of planets we found with
• 37:22
  very heavily misaligned, very heavily tilted
• 37:25
  orbits. And that's really odd, but they tend
• 37:28
  to be the hot Jupiters. Most of those really
• 37:29
  tilted orbits are planets really close in.
• 37:32
  Excuse me, with my phone making a noise
• 37:35
  there. I should really have put that on
• 37:36
  silent. And I normally would do.
• 37:38
  Andrew Dunkley: Yeah, it reminds me, I haven't put mine on
• 37:40
  silent either. There we go.
• 37:41
  Jonti Horner: Yes. Naughty, naughty, naughty. I will call
• 37:43
  that person back a little bit later on. I
• 37:44
  suspect they want to talk about the Orionids
• 37:46
  because that seems to be what's happening all
• 37:48
  the time at the minute. But anyway, what I
• 37:50
  was saying is essentially the more massive
• 37:52
  stars seem to have a subset of them have
• 37:54
  these really heavily misaligned hot Jupiters
• 37:57
  that are all really close in. But we normally
• 38:00
  only find them when planets are really,
• 38:02
  really close in. This weird
• 38:04
  superpuff planet that is a superpuff, despite
• 38:06
  the fact it's too far from its star to be a
• 38:09
  normal superpuff. It's one of the furthest
• 38:11
  we've ever found, is also one of the most
• 38:13
  distant planets from a star that we've ever
• 38:15
  found on such a misaligned orbit. Its orbit
• 38:18
  is tilted by 82 degrees to the plane of its
• 38:21
  star's equator.
• 38:22
  Andrew Dunkley: Wow.
• 38:23
  Jonti Horner: It's almost up at right angles. So I know
• 38:25
  that was a lot of long explanation. But
• 38:27
  you've got a planet with two things that are
• 38:29
  very, very unusual about it at the same time.
• 38:33
  Which leads to the obvious thought that maybe
• 38:35
  these two things are linked. And maybe what
• 38:37
  we're seeing with these two things is kind of
• 38:40
  cause and effect or something that's telling
• 38:42
  us about the history of this planet, about
• 38:44
  how it's got onto that extremely tilted
• 38:47
  orbit. Maybe it's telling us that the
• 38:49
  encounters and the stirring that have flung
• 38:51
  it onto that orbit are relatively recent
• 38:54
  and they've caused a lot of tidal heating. So
• 38:57
  the super puff nature of the planet is an
• 38:59
  artifact of its recent transition
• 39:02
  to a totally new highly tilted orbit, maybe
• 39:05
  through very close encounters with another
• 39:06
  planet that's been ejected from the system.
• 39:09
  We just don't know yet. This is a weird
• 39:11
  thing in a lot of ways. This thing doesn't
• 39:14
  fit the models of how we'd expect most super
• 39:17
  puff planets to look. I would expect most how
• 39:19
  the tilted planets to look. And that makes it
• 39:21
  hugely exciting for scientists because it's
• 39:24
  allowing us to get a window into rare things
• 39:26
  that might not normally happen.
• 39:28
  Andrew Dunkley: Yeah. So, um, just a quick question to finish
• 39:30
  this one off. If that planet is
• 39:33
  basically rotating on the vertical,
• 39:36
  um, around the sun, would
• 39:39
  all other planets orbiting that
• 39:42
  sun do the same thing? Or could they be on an
• 39:44
  equatorial orbit, if there are any?
• 39:47
  Jonti Horner: That's the kind of question we want to
• 39:49
  answer. I mean, um, getting
• 39:52
  to a highly tilted orbit can happen a number
• 39:54
  of different ways. So there's a few different
• 39:55
  models for how this could happen, and they're
• 39:57
  not mutually exclusive. One way that you
• 40:00
  can pump up the tilt of a planet's orbit
• 40:03
  is through close encounters between planets,
• 40:05
  stirring each other up. However, that's not
• 40:08
  that effective. And I know that coming from a
• 40:11
  solar system astronomy point of view, comets
• 40:13
  coming in that are scattered by planets very
• 40:16
  rarely get their orbital inclinations changed
• 40:18
  dramatically in a single encounter. That's
• 40:20
  really hard to make happen. You can set it up
• 40:22
  so that it does, but that's going to be quite
• 40:24
  rare. There is another effect
• 40:26
  that you can get which can work with that,
• 40:28
  called the, um, quasi effect,
• 40:32
  where once you've got two objects that are
• 40:34
  massive, inclined by about 30 degrees to
• 40:37
  each other, you can get this periodic
• 40:39
  exchange of energy, of
• 40:42
  momentum, between the eccentricity and the
• 40:44
  inclination of an orbit, and you can cause it
• 40:45
  to oscillate from having a low
• 40:48
  eccentricity and highly tilted
• 40:51
  orbit to a high eccentricity, low tilt orbit
• 40:53
  relative to a given plan. And what that can
• 40:56
  do is it can cause the object to go from a
• 40:59
  nearly circular orbit at a relatively low
• 41:01
  tilt, to a higher tilt and more eccentric
• 41:03
  orbit, and back and forth, oscillating back
• 41:06
  and forth, then you can decouple the planet.
• 41:08
  Because when you're on the highly eccentric
• 41:09
  orbit, you get close enough to the star to
• 41:12
  get that tidal circularization process we
• 41:14
  were talking about, drop it out of that
• 41:17
  resonance, trap it at that high inclination
• 41:19
  orbit, and then it becomes a more circular
• 41:20
  orbit. And what that would do would leave you
• 41:23
  with two very misaligned objects that are
• 41:25
  very, very widely separated. The third
• 41:28
  option, and this is one that my old boss at
• 41:31
  the University of New South Wales many years
• 41:33
  ago, which he favoured, was the idea
• 41:36
  that, uh, the angular momentum vector of
• 41:38
  material Coming in with a star forms.
• 41:40
  Everybody just assumes that the disk around
• 41:42
  the star and the material coming in late will
• 41:44
  be coming in with the same spin axis as the
• 41:46
  material that formed the star in the first
• 41:48
  place. And given that you're in a very
• 41:50
  dynamic and very evolving environment of a
• 41:52
  young stellar cluster, that's not necessarily
• 41:55
  the case. And so you can imagine a situation
• 41:57
  where a star forms with a disk that is very
• 42:00
  misaligned to the star, and then the planets
• 42:01
  form in that disk. And then all the planets
• 42:04
  will be in the same orbital plane, but they'd
• 42:06
  be very misaligned with the rotation of the
• 42:08
  star. So these are all different models, and
• 42:10
  doubtless all of them have happened
• 42:12
  somewhere. And what we want to learn is how
• 42:14
  common they are, how they work so
• 42:17
  that we can get a better handle on planet
• 42:19
  formation. Because what all these kind of
• 42:20
  discoveries remind us is that a planets
• 42:23
  themselves are more diverse than we could
• 42:25
  ever possibly have imagined. But also their
• 42:27
  orbits and their architectures and the setups
• 42:29
  of planetary systems are also incredibly
• 42:32
  diverse. And we're, in all honesty, just
• 42:34
  scratching the surface. But finding the
• 42:36
  oddities allows us to better understand the
• 42:38
  process by which planets formed and therefore
• 42:41
  better understand our own place in the cosmos
• 42:43
  and how our planetary system came to be.
• 42:46
  Andrew Dunkley: Interesting. Yeah. The more we look, the
• 42:48
  stranger the things are, uh, that we're
• 42:50
  finding and some defy explanation. And this,
• 42:52
  this is certainly one of those. So if you'd
• 42:55
  like to read all about it, you can do so
• 42:57
  through the archive website.
• 43:02
  Jonti Horner: Okay.
• 43:02
  Andrew Dunkley: We checked all four systems, space
• 43:05
  nets, uh, one final story, and this
• 43:08
  takes us close to home. And Earth's magnetic
• 43:11
  fields, um, are acting.
• 43:13
  Jonti Horner: A little bit weird.
• 43:14
  Andrew Dunkley: Uh, and we've got this giant weak spot,
• 43:17
  uh, in, um, this is in the
• 43:20
  Atlantic, I believe, is it?
• 43:21
  Jonti Horner: Yes, South Atlantic. Now this is one where I
• 43:24
  will stress that I'm not an expert in
• 43:26
  magnetic fields, I'm not a geophysicist, but
• 43:28
  this is still so cool we have to talk about
• 43:30
  it. And for those listening in who understand
• 43:32
  this better than I am, please be gracious
• 43:34
  when you tell me what I got wrong when you
• 43:36
  comment. But anyway,
• 43:39
  um, this work is the result of a group of
• 43:41
  satellites run by the European Space Agency
• 43:44
  called Swarm. And they are satellites that
• 43:47
  are monitoring Earth's magnetic field. And,
• 43:49
  um, when you learn about the Earth's magnetic
• 43:51
  field at high school, you basically get this
• 43:53
  idea that the Earth is this giant bar magnet
• 43:56
  and has this bar magnetic type magnetic field
• 43:57
  around us. And that's about it. But in
• 44:00
  actuality, the Earth's Magnetic field is
• 44:02
  incredibly complicated. And there are areas
• 44:04
  on our planet where it's stronger than
• 44:06
  average and areas where it's weaker than
• 44:07
  average. It has two dominant
• 44:10
  poles. It's got the north magnetic Pole and
• 44:12
  the south magnetic Pole. But they're not
• 44:14
  necessarily aligned in such a way that a line
• 44:16
  between them would run perfectly through the
• 44:18
  center of the Earth. They are both moving as
• 44:21
  time goes on. And that's all because the
• 44:23
  process that generates the Earth's magnetic
• 44:25
  field is really complicated and is down to
• 44:28
  moving fluids, moving molten iron
• 44:31
  in the Earth's outer core, essentially. So
• 44:33
  you've got this molten
• 44:36
  ferromagnetic kind of material sloshing
• 44:38
  around, driving a dynamo that creates this
• 44:40
  time varying magnetic field that does all
• 44:42
  sorts of weird stuff. For a very long
• 44:45
  time, it's been known that there is this
• 44:46
  anomaly in the South Atlantic where the
• 44:48
  magnetic field is somewhat weaker than
• 44:51
  anywhere else on the planet. And, um, this
• 44:53
  has been, I've even heard it described as,
• 44:55
  uh, being kind of the Bermuda Triangle of
• 44:57
  space. It's a place where satellites
• 44:59
  misbehave. Yeah. And it's something that
• 45:02
  space agencies, governments, and now
• 45:04
  commercial entities are very aware of,
• 45:06
  because where you've got a weaker magnetic
• 45:08
  field, you've got less protection from the
• 45:10
  vagaries of cosmic rays, solar radiation,
• 45:12
  solar storms, things like that. So it's a
• 45:15
  place where your satellites are going to be
• 45:16
  more vulnerable than normal and more likely
• 45:19
  to throw up errors and have problems. And
• 45:21
  it's really interesting to study how these
• 45:23
  things change with time. Because if you think
• 45:25
  about the roiling and the boiling of that,
• 45:27
  uh, molten material in the Earth in a core,
• 45:29
  that's going to vary with time. And that's
• 45:31
  what these satellites have been mapping. And,
• 45:34
  um, what they've found is that this South
• 45:35
  Atlantic Anomaly, the Bermuda Triangle of the
• 45:38
  South Atlantic, from a magnetism point of
• 45:40
  view, has been changing quite dramatically.
• 45:42
  They've been mapping it since they were
• 45:44
  launched in 2014. So we've 11 years worth of
• 45:46
  data now. And, um, what they've found is that
• 45:49
  that anomaly in the South Atlantic has got
• 45:51
  bigger. It now has got bigger
• 45:54
  Biennaria equivalent to kind of Central
• 45:56
  Europe, Western Europe. So that's a fairly
• 45:58
  big amount of growth in just
• 46:01
  around. At the same time, the magnetic North
• 46:04
  Pole is merrily trundling its way, moving
• 46:06
  from Canada to Siberia. There
• 46:08
  are a few extra strong patches of the
• 46:11
  magnetic field. One of those in Siberia is
• 46:13
  getting stronger and stronger. The other
• 46:15
  strong patch in Canada is getting weaker. But
• 46:17
  it's still a strong patch. There's One
• 46:19
  possibly over by India. And so we're getting
• 46:22
  this impression of the
• 46:25
  magnetic field of the Earth varying on
• 46:27
  timescales of years and decades at uh, quite
• 46:29
  a rapid way, fluctuating probably more than
• 46:32
  we'd have ever thought of during from ground
• 46:33
  based observations. Now it's interesting
• 46:37
  from just purely a science point of view to
• 46:39
  see everything wibbling and wobbling. It's
• 46:42
  also really important for people launching
• 46:44
  satellite constellations to be aware of this
• 46:46
  and to mitigate for it and to uh, plan their
• 46:48
  orbits around it. Because if you've got one
• 46:50
  point in orbit around the Earth that is more
• 46:51
  vulnerable than the others, fortunately it's
• 46:54
  over the ocean. But maybe you want to have
• 46:55
  fewer satellites going through that area so
• 46:58
  that you maximize the lifetime of your
• 47:00
  satellites in terms of their working lifetime
• 47:02
  and things like that. So it's useful from
• 47:04
  that.
• 47:04
  Now, a couple of the things that have been
• 47:05
  mentioned in the discussion of this, uh, in
• 47:07
  order to see, I don't fully understand how
• 47:09
  they're connected. One is that uh, the data
• 47:12
  from these satellites has been said to
• 47:14
  suggest that that motion of the pole from
• 47:16
  Canada to Siberia has been happening since
• 47:19
  the mid 19th century. Now I think that's
• 47:22
  probably something that's getting a bit lost
• 47:23
  in translation because I'm not sure how
• 47:26
  observations going back to 2014 can tell you
• 47:28
  about something that was happening in the
• 47:29
  1800s. Yeah, I suspect what the authors have
• 47:32
  probably said in the original paper is there
• 47:34
  have been suggestions in measurements
• 47:37
  from the ground that the pole has been moving
• 47:39
  for all this time. But what we've got now is
• 47:42
  a very clear model of how it's moved over the
• 47:44
  last 11 years because we've been observing it
• 47:46
  and that somehow got shifted to the results
• 47:48
  suggesting that motion has been happening for
• 47:51
  that length of time. Um, I think that's
• 47:53
  probably a miscommunication thing because I
• 47:55
  don't see any way that an 11 year period of
• 47:58
  observation can accurately tell you what was
• 48:00
  happening 150 years ago. You need other
• 48:02
  observations for that. But you know that
• 48:04
  movement is an ongoing thing. The other thing
• 48:07
  to probably reassure people. I know people
• 48:09
  sometimes worry that this means our magnetic
• 48:10
  field's about to uh, cease and desist and
• 48:13
  turn around and the end times will come and
• 48:15
  it will be apocalypse and all the rest of it.
• 48:17
  This South Atlantic Anomaly, uh,
• 48:20
  is something where geological evidence and
• 48:23
  core drilling and sampling of places where
• 48:25
  the magnetic field gets frozen in. So if you
• 48:27
  look at rocks, you can tell what the magnetic
• 48:29
  field was doing in the past. Yeah. That
• 48:32
  tells us that this anomaly over The South
• 48:35
  Atlantic has been there in one form or
• 48:37
  another for at least the last 11 million
• 48:38
  years. So it's not new and
• 48:42
  scary. Rather we're seeing something that has
• 48:45
  been going on for a long time, but wibbling
• 48:47
  and wobbling and it's sometimes bigger and
• 48:48
  sometimes smaller.
• 48:49
  Andrew Dunkley: It's normal.
• 48:51
  Jonti Horner: This is normal. But it's amazing that we can
• 48:53
  now get information about it on such
• 48:56
  timescales. And much as it's out of my area
• 48:58
  of expertise, I think it's yet another of
• 49:00
  these fabulous examples of how
• 49:03
  what you get taught at school is a very
• 49:05
  simplified version of the way the universe
• 49:08
  actually works. And what we'll learn from
• 49:10
  science is not always that what you were
• 49:12
  taught was wrong, but rather that what you
• 49:14
  were taught was incomplete and we need to
• 49:15
  learn more. So we've gone from, you know, if
• 49:18
  you'd asked me as an 8 year old what the
• 49:19
  Earth's magnetic field's like, I'd have
• 49:21
  probably parroted. It's like you've got a bar
• 49:22
  magnet and the magnetic field has a North
• 49:24
  pole and a South pole and there's an
• 49:26
  inference there that it's unchanging. There's
• 49:28
  an inference that everywhere at the same
• 49:30
  distance from the pole has the same magnetic
• 49:32
  field strength, all these things, when in
• 49:34
  fact it's a much more dynamic situation than
• 49:37
  that. And it's much more like looking at a
• 49:39
  boiling kettle through a glass window on the
• 49:42
  side and seeing the water bubbling and
• 49:43
  roiling around, rather than just looking at
• 49:46
  the steam coming out and saying, oh, look,
• 49:47
  the steam.
• 49:48
  Andrew Dunkley: My answer to that question at school would
• 49:50
  have been the what?
• 49:53
  Um, yeah, but it's also, uh, indicative
• 49:56
  of how very active the interior
• 49:59
  of the planet is. And if
• 50:02
  like I, I read the news every day and I
• 50:05
  this particular types of news that I look out
• 50:07
  for and uh, one of them's volcanic
• 50:10
  activity. And there's been a heck of a lot
• 50:13
  of stuff going on lately, uh, all over the
• 50:15
  planet, but, uh, a few places are starting to
• 50:18
  pop up as, uh, active. There's a particular,
• 50:21
  uh, volcano in Iran that they thought was
• 50:24
  extinct that's now starting to show signs of,
• 50:26
  um, waking up.
• 50:28
  Jonti Horner: Yeah. But they don't think has erupted for
• 50:31
  several million years. I mean, lively
• 50:34
  now.
• 50:34
  Andrew Dunkley: Yeah, there's all sorts of things happening
• 50:36
  like that. So who knows, the Dubbo volcano
• 50:39
  maybe may make a comeback. Yes, we did
• 50:42
  have one here millions of years ago.
• 50:44
  Jonti Horner: Yeah. Well, I live in an area on the Darling
• 50:46
  Downs that's incredibly fertile and it's
• 50:48
  incredibly fertile because there was a super
• 50:50
  volcano, erupting, here tens of
• 50:53
  millions of years ago that fertilized the
• 50:55
  place. You know, we have got volcanoes in
• 50:58
  Australia that have been active on the
• 51:00
  mainland within the scope of knowledge of our
• 51:02
  wonderful traditional owners here. I think
• 51:05
  some of the ski resorts in Victoria last
• 51:07
  erupted since the last ice age. Yep.
• 51:10
  Andrew Dunkley: The only active volcano in
• 51:12
  Australian territory is an external
• 51:15
  Australian territory southwest of Western
• 51:17
  Australia. I can't think of the name of the
• 51:19
  island, but that's the only active volcano
• 51:22
  uh, in, in Australian territory. But we've
• 51:25
  got several that aren't far away around
• 51:27
  Indonesia and, and,
• 51:30
  and uh, of course New Zealand.
• 51:31
  Jonti Horner: And I mean we've got the ones
• 51:34
  that are classed as dormant that have erupted
• 51:36
  so recently that we know they'll erupt again.
• 51:38
  Yeah, I, we had this beautiful road trip
• 51:41
  about 18 months ago where we left Toowoomba,
• 51:44
  we picked my partner's parents up down in
• 51:46
  northern New South Wales and we went all the
• 51:47
  way over to Adelaide and back around the
• 51:49
  coast. Coming back up, we did an awesome
• 51:50
  three week trip. Yeah. And we stopped at a
• 51:52
  place I think was called Tower Hill, um, just
• 51:55
  on the Victorian side of the border with
• 51:57
  South Australia. It was fabulous spot for
• 51:59
  bird life. Had the most amazing view of wedge
• 52:01
  tailed eagles and stuff. But that is a uh,
• 52:03
  relatively recent maar, I think they're
• 52:06
  described as. And there's a load of these
• 52:08
  around that area which are uh, not quite mud
• 52:11
  volcanoes and stuff, but they're not, oh my
• 52:14
  God. Explosive Hawaiian type volcanic
• 52:15
  activity, but they're volcanic activity in
• 52:18
  recent geological time that will happen
• 52:20
  again. It's all that kind of stuff. Mount
• 52:23
  Buller I think is the ski resort that last
• 52:25
  erupted about 6,000 years ago on
• 52:27
  timescales longer than our lifetimes. The
• 52:30
  Earth's a much more dynamic place than we
• 52:32
  think. And this is part of the wonders
• 52:35
  of working with and talking to people who
• 52:38
  interface with the traditional owners of the
• 52:40
  land and do it in a respectful enough way to
• 52:42
  be able to learn some of the knowledge
• 52:43
  they've passed down because there is oral
• 52:45
  history passing down memories of these events
• 52:48
  happening. People on this continent now have
• 52:51
  a living oral history that recorded
• 52:53
  events tens of thousands of years ago and
• 52:56
  have passed them down in a form that we can
• 52:58
  identify them and learn from them and get a
• 53:01
  feel for these events that are much rarer
• 53:04
  than we'd normally observe. You know, even in
• 53:06
  the kind of nominally modern science period.
• 53:08
  400 years.
• 53:09
  Andrew Dunkley: Yeah.
• 53:10
  Jonti Horner: When you talk about something 6,000 years
• 53:12
  ago, we can get information about it now. I
• 53:15
  think that's magical.
• 53:16
  Andrew Dunkley: It is, it is indeed. Uh, if you would like to
• 53:18
  read about the South Atlantic Anomaly, uh,
• 53:21
  and all the stories we've talked about today,
• 53:23
  you can, uh, do it the easy way and go to
• 53:25
  space.com. uh, Jonti,
• 53:28
  we're done for another day. Thank you.
• 53:30
  Jonti Horner: That's an absolute pleasure. Thank you so
• 53:32
  much. And my phone is now on silent, so.
• 53:34
  Andrew Dunkley: And we just finished. Um. Yeah. All right,
• 53:37
  we'll catch you soon on the Q and A episode.
• 53:39
  Uh, Jonti Horner, professor of Astrophysics
• 53:42
  at the University of Southern Queensland, and
• 53:43
  thanks to Huw in the studio, couldn't be with
• 53:45
  us today. He took a ride on a SpaceX rocket
• 53:47
  and everything was going fine until they came
• 53:49
  in to land. Then he saw a button and it said,
• 53:52
  don't push. Well, this is Huw we're talking
• 53:54
  about. So I think you saw that, uh,
• 53:56
  explosive, um,
• 53:59
  catastrophe. Anyway, he'll be back with us
• 54:01
  one day after the injuries are, ah, all done
• 54:03
  and dusted. Uh, and from me, Andrew Dunkley,
• 54:06
  thanks for your company. Don't forget to
• 54:07
  visit us on our website or our social media
• 54:09
  sites. Uh, and you can interact with, uh.
• 54:12
  Jonti Horner: Each other there as well.
• 54:13
  Andrew Dunkley: Until next time. Bye for now.
• 54:17
  Jonti Horner: You'll be listening to the Space Nuts.
• 54:19
  Andrew Dunkley: Podcast.
• 54:21
  Jonti Horner: Available at Apple Podcasts, Spotify,
• 54:24
  iHeartRadio or your favorite podcast
• 54:27
  player. You can also stream on
• 54:29
  demand@bytes.com.
• 54:31
  Andrew Dunkley: This has been another quality podcast
• 54:33
  production from bytes.com.