Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #473: Alien Volcanoes, Black Hole Mysteries & Uranus Revisited

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#473: Alien Volcanoes, Black Hole Mysteries & Uranus Revisited · Space Nuts: Astronomy Insights & Cosmic Discoveries

• 0:00
  Speaker 1: Hi there, Thanks for joining us yet again. I don't
• 0:03
  Speaker 1: know how you do it, but welcome along. This is
• 0:05
  Speaker 1: Space Nuts with Andrew Dunkley, your host. Hope you're well.
• 0:09
  Speaker 1: This episode is dedicated to volcanoes, supernovas that were not
• 0:15
  Speaker 1: and Voyager two, which told us something that turned out
• 0:18
  Speaker 1: not to probably be true. It's all coming up on
• 0:21
  Speaker 1: this episode of Space Nuts. Fifteen second guidance in Channel
• 0:26
  Speaker 1: ten nine ignition Squench.
• 0:29
  Speaker 2: Space Nuts NYE or three two one Space Nuts has
• 0:37
  Speaker 2: been actually bought it.
• 0:38
  Speaker 1: Bill's good and joining us again to go over all
• 0:41
  Speaker 1: of that is Professor Fred. What's an astronomer at large?
• 0:44
  Speaker 1: Hello Fred, Hello Andrew.
• 0:46
  Speaker 2: I'm still still at large or on the loose really now,
• 0:49
  Speaker 2: but that's all right.
• 0:51
  Speaker 1: I've seen a few variations on what people think you
• 0:54
  Speaker 1: should be called. Now we should. We'll keep an eye
• 0:56
  Speaker 1: on those. If we're getting good ones, I'll pass them along.
• 0:59
  Speaker 1: You might want to check anti business card. Yeah, yes,
• 1:03
  Speaker 1: I'm right now. There's a story that we're going to
• 1:07
  Speaker 1: start with today that brings into play something that I
• 1:11
  Speaker 1: am very excited about, and that's volcanoes. I've visited several
• 1:16
  Speaker 1: over my time traveling around the world, and you have
• 1:20
  Speaker 1: visited a couple yourself, including that most infamous one that
• 1:25
  Speaker 1: grounded all the plains in the Northern Hemisphere when it
• 1:29
  Speaker 1: blew a gas get in twenty ten. Was it the
• 1:33
  Speaker 1: one in Iceland? What's it called again? Because I can't pronounce.
• 1:35
  Speaker 2: It and it means, let me get it right, I
• 1:43
  Speaker 2: think it means island, mountain, glacier. Yourkle is a glacier.
• 1:48
  Speaker 2: So the double L, so there's two double l's in it,
• 1:51
  Speaker 2: and double L is in Icelandic has the sound of
• 1:56
  Speaker 2: it's not just it's got a kind of squeeze of
• 1:59
  Speaker 2: the of the chigs before it. So if you if
• 2:09
  Speaker 2: one of our on one of our visits to Iceland,
• 2:12
  Speaker 2: a lovely guy who was our guide at the time,
• 2:15
  Speaker 2: he said he'd spent a few years in Germany and
• 2:20
  Speaker 2: I did become fluent in German, so I spoke everybody
• 2:23
  Speaker 2: in Germany, came back to Iceland and got back into
• 2:26
  Speaker 2: Icelandic and he said he's jaw ached because of what
• 2:30
  Speaker 2: you've got to do to get the pronunciation. He said,
• 2:35
  Speaker 2: it wasn't used to it. You know, it's jaw started.
• 2:38
  Speaker 1: I have that. Well, the only go on, go on,
• 2:42
  Speaker 1: I was going to say that explains why the vikings
• 2:44
  Speaker 1: were so angry all the time, no one could have
• 2:46
  Speaker 1: to stand them.
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  Speaker 2: Yes, yeah, that's right. Anyway, it's good. I was going
• 2:53
  Speaker 2: to say, that's the only Icelandic word that I know.
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  Speaker 1: And you and only I tak tok. You said you
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  Speaker 1: told us a very interesting factoid about it, which I
• 3:04
  Speaker 1: think we should share again.
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  Speaker 2: That it was the world's first carbon negative volcano because
• 3:11
  Speaker 2: by grounding the world's airlines for something like a week
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  Speaker 2: it was getting on for a week, it took more
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  Speaker 2: carbon out of the atmosphere than it put in, which
• 3:21
  Speaker 2: is really quite an astonishing It's unthinkable.
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  Speaker 1: Isn't it, because it was not a small eruption.
• 3:27
  Speaker 2: No sending stuff up a long way. That's right.
• 3:31
  Speaker 1: And you've stood on the edge of that thing, haven't
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  Speaker 1: you on.
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  Speaker 2: The edge of the glacier that runs over it. Yes,
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  Speaker 2: it's underneath the glacier, which is the uklu bit of
• 3:40
  Speaker 2: the word.
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  Speaker 1: It's just scary to think about it.
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  Speaker 2: I'll send you the picture we might have. We've got
• 3:49
  Speaker 2: a picture of me talking the ABC right at the
• 3:50
  Speaker 2: snout of the glacier that runs over it.
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  Speaker 1: A well one one volcano that we visited ended up
• 3:59
  Speaker 1: erupting not long after we were there. As is our habit,
• 4:02
  Speaker 1: whenever we travel, something happens, and it stopped air traffic
• 4:06
  Speaker 1: around the Asia Pacific region for a while. That was yeah.
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  Speaker 1: And as we speak, one airline that I'm aware of
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  Speaker 1: is canceled all flights out of den Pasar in Indonesia
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  Speaker 1: at Bali. Yes, because of another volcanic.
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  Speaker 2: Eruption, Yes, eruption. Yeah, it's all huntling.
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  Speaker 1: It is certainly happening. Now, that's our planet and it's
• 4:29
  Speaker 1: active volcanoes. And we know of a couple of other
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  Speaker 1: places in our Solar system that seem to have volcanic activity,
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  Speaker 1: maybe Venus EOO one of them.
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  Speaker 2: Yes, it's probably the most volcanically active body in the
• 4:43
  Speaker 2: Solar system is Io.
• 4:45
  Speaker 1: Yes, but we are talking about an exoplanet that they
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  Speaker 1: think might be volcanic. That's quite a fine.
• 4:54
  Speaker 2: It is. It rejoices in the name. Let's get this
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  Speaker 2: out of it out of the way. L ninety eight
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  Speaker 2: dash fifty nine D. And that planet was a discovery
• 5:07
  Speaker 2: from the Space Telescope, which we've talked about a lot,
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  Speaker 2: because it was the space telescope that really followed on
• 5:15
  Speaker 2: from Keppelo, which was a telescope designed to look for
• 5:17
  Speaker 2: the dip in the light of a star because of
• 5:20
  Speaker 2: the planet going around it. Likewise, tests did the same thing,
• 5:23
  Speaker 2: and both those two together absolutely revolutionized the science of
• 5:27
  Speaker 2: planet discovery. So L ninety eight to fifty nine D
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  Speaker 2: discovered by tests back in twenty nineteen and has now
• 5:36
  Speaker 2: been analyzed in some detail because of the technology that
• 5:42
  Speaker 2: we can apply. I've good a feeling this has come
• 5:44
  Speaker 2: from the JWST, but I need to check that anyway. Yes,
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  Speaker 2: that's right. It has been changed with telescope observations that
• 5:56
  Speaker 2: have given us this new information, which is that particular
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  Speaker 2: planet L ninety eight fifty nine D. I do, like
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  Speaker 2: the name, has signatures in its atmosphere of some of
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  Speaker 2: the products which we know are associated with the volcanic eruptions,
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  Speaker 2: and so sulfur dioxide is one of them, and hydrogen
• 6:23
  Speaker 2: sulfide bad egg gas, that's another. And what the scientists
• 6:28
  Speaker 2: who've done this work are suggesting is that the presence
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  Speaker 2: of those, combined with the absence of other ones which
• 6:35
  Speaker 2: are much more common, like carbon dioxide, the presence of
• 6:39
  Speaker 2: those suggest that we have extreme conditions on L ninety
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  Speaker 2: eight fifty nine D. Either volcanic activity on a big scale,
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  Speaker 2: or even a molten surface. Now we think that at
• 6:58
  Speaker 2: some stage in its past surface was molten. It was
• 7:01
  Speaker 2: what we call a lava world, and we may be
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  Speaker 2: seeing this particular planet basically doing the same sort of thing.
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  Speaker 2: So just to give it some statistics, Andrew, it's about
• 7:16
  Speaker 2: fifty percent bigger than the Earth. It's what we call
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  Speaker 2: a super Earth in the scale of exoplanets. It's about
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  Speaker 2: thirty five light years away as the crow flies, and
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  Speaker 2: it has a record. It's a record breaker because if
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  Speaker 2: the details of these observations are confirmed, and they're still
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  Speaker 2: fairly tentative, the details of the chemistry of the atmosphere,
• 7:38
  Speaker 2: if they're concerned, if they're confirmed a bigger partner, it
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  Speaker 2: would be the smallest known exoplanet with an atmosphere. So
• 7:46
  Speaker 2: it's interesting because we're now starting to probe down to
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  Speaker 2: Earth sized planets here with the ability to use spectrotrocopy
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  Speaker 2: to determine what's in their atmospheres. So really interesting observation. Yeah.
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  Speaker 1: Absolutely, And it's not that far away this one, is
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  Speaker 1: it either Is it.
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  Speaker 2: Thirty five light years? No, that's right, it's you know,
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  Speaker 2: it's certainly within the Sun's local neighborhood. So not that
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  Speaker 2: that makes it any difference. You know, once you get
• 8:16
  Speaker 2: beyond the orbit of Neptune, you're talking about a different
• 8:20
  Speaker 2: sort of distance scale altogether from what we used to
• 8:24
  Speaker 2: in the Solar System. But nevertheless, it's good and just
• 8:28
  Speaker 2: a quick footnote to how we can measure what's in
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  Speaker 2: the atmosphere of an exoplanet, and that it's a very
• 8:37
  Speaker 2: very delicate measurement and needs the best instrumentation. What you
• 8:42
  Speaker 2: do is you wait until the planet transits in front
• 8:45
  Speaker 2: of its parent star, and you look at the spectrum
• 8:48
  Speaker 2: of the parent star, and then you compare that with
• 8:51
  Speaker 2: what the parent star looks like without the planet in
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  Speaker 2: front of it, because and the difference in them is
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  Speaker 2: caused by the light of the star passing through the
• 9:03
  Speaker 2: additional layer of the atmosphere of the planet which is
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  Speaker 2: sitting in front of it. And so even though that
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  Speaker 2: atmosphere might be very small in diameter compared with the
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  Speaker 2: diameter of the star, in fact it's a ring of course,
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  Speaker 2: because you've got the planet itself blocking it. That area
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  Speaker 2: is very small compared with the surface area of the star.
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  Speaker 2: As we see it, it's still with the sensitive equipment
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  Speaker 2: that we have. Now it's still possible to tease out
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  Speaker 2: what the spectrum lines, the spectral signature of the gases
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  Speaker 2: in the atmosphere of the exo planets are. And it's
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  Speaker 2: a technique that's been used more and more and I
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  Speaker 2: think has a great future. And of course once we
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  Speaker 2: get into the ELT League, the extremely Large Telescope League,
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  Speaker 2: there will be a standard kind of measurement that we'll
• 9:47
  Speaker 2: be hearing about every week. I'm sure.
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  Speaker 1: Yes, that's so very exciting. Now. I remember going to
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  Speaker 1: a lecture on m said at once where they were
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  Speaker 1: talking about using spectrographs i'll say, to analyze exoplanets. And
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  Speaker 1: now it's sort of becoming the norm, which is very exciting.
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  Speaker 1: That forecast was spot on.
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  Speaker 2: That might even have been one of the artellect journals
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  Speaker 2: of the Bock Lectures. That's right, Yeah, so I was
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  Speaker 2: involved in, yes, the book lectures. Yeah.
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  Speaker 1: Now I did have a question, do we think that
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  Speaker 1: L ninety eight fifty nine D is independently volcanic or
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  Speaker 1: is it being influenced by something else? EO is kind
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  Speaker 1: of volcanic because Jupiter gifted a bit of a crushing
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  Speaker 1: hug all the time.
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  Speaker 2: Yes, exactly. That's right, And that's a great question. And
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  Speaker 2: the answer is probably because it goes around its parents'
• 10:50
  Speaker 2: star in if I remember it's just a few days.
• 10:54
  Speaker 2: I can't remember just exactly how many days it is.
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  Speaker 2: You might have it in front of the e seven
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  Speaker 2: and a half earth days. So what we take a
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  Speaker 2: year to do around the Sun, that particular planet takes
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  Speaker 2: seven and a half days to do around it around
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  Speaker 2: its parents star. So it means it's very close to
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  Speaker 2: its parents' star, and much closer than mercury is to
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  Speaker 2: the Sun. And that's another reason why it might be
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  Speaker 2: volcanically active to the degree that we think it is.
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  Speaker 2: And it's not just the radiant heat of the star
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  Speaker 2: itself because it's close by. It's that closeness that gives
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  Speaker 2: the planet a squash and a squeeze every time it
• 11:36
  Speaker 2: goes around and causes this heating of its interior by
• 11:40
  Speaker 2: what we call tidal forces, exactly the same mechanism that
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  Speaker 2: keeps EO volcanically active.
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  Speaker 1: Yes, so it's a bit bigger than Earth at one
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  Speaker 1: and a half times our size, but it's surprisingly much stinkier.
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  Speaker 2: Place we talked about h to us a recent episode
• 12:01
  Speaker 2: didn't we because it was the nickname given to the
• 12:04
  Speaker 2: to the radar that was used on luncaster bombers that
• 12:09
  Speaker 2: because it smells bad. That's what they said.
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  Speaker 1: Yes, absolutely, And if you want to read about that
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  Speaker 1: particular story fizz dot org. Of course, phy s dot org.
• 12:22
  Speaker 1: Just do a search for a distant planet seems to
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  Speaker 1: have a sulfur rich atmosphere, hinting at alien volcanoes. This
• 12:30
  Speaker 1: is Space Nuts with Andrew Dunkley and Professor Fred Watson
• 12:36
  Speaker 1: Nepace Nuts. Now, Fred, we get questions semi regularly about supernovae,
• 12:45
  Speaker 1: those cataclysmic explosions of stars that can be sometimes seen
• 12:51
  Speaker 1: in daylight if they're close enough to us, and there's
• 12:54
  Speaker 1: been a couple in recorded history, and they ultimately collapse
• 12:58
  Speaker 1: and become a black hole. Now we've got a situation
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  Speaker 1: that's so unusual and somewhat rare, a super and nova
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  Speaker 1: that did not happen, but the star still turned into
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  Speaker 1: a black hole. That is that is sort of on
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  Speaker 1: the realm of weird.
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  Speaker 2: It's weird, that's right, although sort of understood. The mechanism is,
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  Speaker 2: you know, predicted by theory that you can do this,
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  Speaker 2: but it is so unusual, you know, We always think
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  Speaker 2: of black holes being formed in super and over explosions,
• 13:35
  Speaker 2: and here we've got something that doesn't detonate, so it
• 13:40
  Speaker 2: basically the collapse takes place without without the explosion. And
• 13:46
  Speaker 2: just to recap why stars do collapse at the end
• 13:50
  Speaker 2: of their lives, you have a situation during the normal
• 13:54
  Speaker 2: lifetime of the star and our sons in this situation
• 13:56
  Speaker 2: where the outward pressure of the radiation coming from the
• 14:00
  Speaker 2: nuclear fusion in its center, and that's what makes the
• 14:02
  Speaker 2: sun shine. That has a pressure on the gas of
• 14:05
  Speaker 2: the Sun, and that just balances the gravitational pull of
• 14:09
  Speaker 2: the whole thing its own self gravity. So you've got
• 14:12
  Speaker 2: this balancing app between the radiation pressure and the gravity.
• 14:17
  Speaker 2: When the sun, oh, the star runs out of its
• 14:21
  Speaker 2: fuel hydrogen fuel, that changes so the radiation it actually
• 14:27
  Speaker 2: goes through a few complex phases, but eventually the radiation stops,
• 14:32
  Speaker 2: and so the battle is won by gravity. Gravity tries
• 14:37
  Speaker 2: to collapse the star in two well if it can
• 14:42
  Speaker 2: a black hole, but it needs to be more than
• 14:43
  Speaker 2: about eight times the mass of the Sun before it
• 14:45
  Speaker 2: will do that, perhaps ten times the mass of the Sun.
• 14:49
  Speaker 2: So that's the process, and it's that sort of collapse
• 14:53
  Speaker 2: that takes place. What you've got is heavy atoms being
• 14:58
  Speaker 2: basically mixing with life atoms and transferring their energy to them.
• 15:03
  Speaker 2: I used to do a trick with them with ping
• 15:06
  Speaker 2: pong balls that demonstrates this quite nicely that if you
• 15:09
  Speaker 2: have atoms different of different masses in close proximity, some
• 15:15
  Speaker 2: of them fall and some of them don't. Some of
• 15:16
  Speaker 2: them bounce outwards and that's what gives rise to the explosion.
• 15:21
  Speaker 2: But with what we've seen in this it's actually in
• 15:24
  Speaker 2: the Andromeda Galaxy. The star itself, it's it's basically a
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  Speaker 2: star that's been studied for a while and has now
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  Speaker 2: just disappeared. And it was known to be a star
• 15:35
  Speaker 2: of the sort of mass that you would form a
• 15:39
  Speaker 2: super and nova, but it's it's just gone and so
• 15:44
  Speaker 2: we believe that that has created a black hole without
• 15:48
  Speaker 2: the explosion. This is research is being done lead actually
• 15:53
  Speaker 2: from mic Massaitudsetts Institute of Technology in the Cavali Institute
• 15:58
  Speaker 2: for Astrophysics and Space Research. So, as I said, it's
• 16:03
  Speaker 2: in the Andromeda Galaxy, it's been observed over a number
• 16:06
  Speaker 2: of years. It did actually brighten for a while, and
• 16:12
  Speaker 2: this is in the infrared waveband back in twenty fourteen.
• 16:16
  Speaker 2: I should give it a name, since we like giving
• 16:18
  Speaker 2: styles names. It's called M thirty one DASHED twenty fourteen
• 16:21
  Speaker 2: dash DS one and it brightened in twenty fourteen, but
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  Speaker 2: then it stayed bright for about three years, but then
• 16:31
  Speaker 2: for another three years it faded away and there's now disappeared.
• 16:36
  Speaker 2: And in twenty twenty three it couldn't detect couldn't be
• 16:39
  Speaker 2: detected in imaging observation, so it's gone. It's thought to
• 16:44
  Speaker 2: have a mass of about six point seven times the
• 16:49
  Speaker 2: mass of the Sun and basically has essentially vanished as
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  Speaker 2: a black hole without what we call an optical outburst,
• 16:59
  Speaker 2: in other words, without a supernova explosion. So it's kind
• 17:02
  Speaker 2: of like a DoD. It reminds me of when you
• 17:04
  Speaker 2: lit fireworks and they didn't go off in the days
• 17:06
  Speaker 2: when you could do that yourself.
• 17:10
  Speaker 1: Yeah, it is a very odd one, and I suppose
• 17:14
  Speaker 1: it's because it wasn't quite big enough. Would that be
• 17:17
  Speaker 1: the basic freezing for it not doing what a supernova
• 17:21
  Speaker 1: normally does.
• 17:23
  Speaker 2: Yes, I think that's right, although it's a very complex process.
• 17:26
  Speaker 2: And once again we're we have a very nice article
• 17:29
  Speaker 2: about this on fizz dot Org, which also references the
• 17:33
  Speaker 2: paper which is currently I think being peer reviewed. It's
• 17:37
  Speaker 2: the paper's title is the Disappearance of a Massive Star
• 17:40
  Speaker 2: marking the birth of a black hole in M thirty one.
• 17:42
  Speaker 2: M thirty one is the posh name for the Andromeda
• 17:45
  Speaker 2: galaxy Messier thirty one. But it's it's a process that
• 17:51
  Speaker 2: has has nuances, And the reason why I mentioned the
• 17:59
  Speaker 2: fizz dot article is that it describes those nuances very well,
• 18:06
  Speaker 2: and it is the whole section which starts with the
• 18:10
  Speaker 2: sentence SUPERNOVAA complex event. Then you can read on and
• 18:14
  Speaker 2: you'll see what's happening with the burst of neutrinos, the
• 18:18
  Speaker 2: neutrino shock. All of these things, you know, are part
• 18:23
  Speaker 2: and parcel of what makes a supernova a super and ova.
• 18:27
  Speaker 2: And sometimes this is this what's called the neutrino shock,
• 18:32
  Speaker 2: which apparently also stalls, always stalls, but usually revives again,
• 18:38
  Speaker 2: and that's what causes the super and ova to explode.
• 18:43
  Speaker 2: The neutrino shock was not revived, it says. So it's
• 18:49
  Speaker 2: let me let me read a little bit from the article,
• 18:53
  Speaker 2: which says in thirty one twenty fourteen DS one, the
• 18:57
  Speaker 2: neutrino shock was not revived. There is certatures were able
• 19:00
  Speaker 2: to constrain the amount of material ejected by the star,
• 19:04
  Speaker 2: and it was far below what a super and ova
• 19:06
  Speaker 2: would eject. And there's a quote from one of the
• 19:09
  Speaker 2: authors or from the paper. Actually, these constraints imply that
• 19:14
  Speaker 2: the majority of stellar material that's more than five times
• 19:17
  Speaker 2: the mass of the Sun collapsed into the core, exceeding
• 19:21
  Speaker 2: the maximum mass of a neutron star and forming a
• 19:24
  Speaker 2: black hole. About ninety eight percent of the star's mass
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  Speaker 2: collapsed and created a black hole with about six point
• 19:30
  Speaker 2: five times the mass of the Sun. So it's it's
• 19:35
  Speaker 2: you know, it's one of these things where we really
• 19:40
  Speaker 2: struggled to those of us who aren't absolutely most in
• 19:45
  Speaker 2: the physics struggle to understand the details. There's a lovely
• 19:48
  Speaker 2: sentence which I like very much in the biz dood
• 19:51
  Speaker 2: Org article M thirty one twenty fourteen. DS one isn't
• 19:54
  Speaker 2: the only failed super and ova or candidate failed super
• 19:57
  Speaker 2: and over the astronomy that astronomers have found. They're difficult
• 20:01
  Speaker 2: to spot because they're characterized by what doesn't happen rather
• 20:04
  Speaker 2: than what does. A super and ova is old to
• 20:07
  Speaker 2: miss because it's so bright and appears in the sky
• 20:10
  Speaker 2: suddenly an ancient stronomers recorded several of them, but there
• 20:14
  Speaker 2: are other ones that have been found that have just disappeared,
• 20:17
  Speaker 2: as this one has.
• 20:18
  Speaker 1: Yeah, so usually when a star explodes supernova style, it
• 20:24
  Speaker 1: produces all these really incredible elements that are well documented.
• 20:32
  Speaker 1: This one, I assume would not have done that, so
• 20:34
  Speaker 1: it didn't pay its toll.
• 20:37
  Speaker 2: Maybe not. I'm not well enough first in supernova physics
• 20:41
  Speaker 2: to know the answer to that definitively, but I think
• 20:44
  Speaker 2: you're probably right Andrew that it didn't, you know, dish
• 20:48
  Speaker 2: out gold and platinum and all the other stuff that
• 20:51
  Speaker 2: permeates the universe from super and over explosions, and I
• 20:54
  Speaker 2: think that will be the case that the ejected material
• 20:57
  Speaker 2: is much too small for it to have paid its toll,
• 21:00
  Speaker 2: as you've said.
• 21:01
  Speaker 1: Yeah, so no lethium, no blue tag gee on the stuff.
• 21:09
  Speaker 1: What are we going to do? Okay, that is a
• 21:12
  Speaker 1: great story, and yeah, something a little bit different, and yeah,
• 21:17
  Speaker 1: I'm guessing we'll get some more black hole questions about that. So, yeah,
• 21:21
  Speaker 1: it does this well, I'll ask one because someone's probably wondering,
• 21:24
  Speaker 1: will this be a different kind of black hole? Will
• 21:26
  Speaker 1: it be unusual in some respects because it didn't it
• 21:30
  Speaker 1: wasn't birthed by a super nova.
• 21:33
  Speaker 2: I don't think so. Black holes are characterized by very
• 21:37
  Speaker 2: few parameters, like one of them is the magnetic field,
• 21:42
  Speaker 2: want's the spin, and so there's not that much to
• 21:47
  Speaker 2: differentiate between one black hole and another except for the mass.
• 21:51
  Speaker 2: And the mass is not that much to it might
• 21:53
  Speaker 2: be a bit smaller than what you would get from
• 21:55
  Speaker 2: a bigger supernova explosion. There's a there's a a theorem
• 22:00
  Speaker 2: that I always like the name of about black holes,
• 22:04
  Speaker 2: and it's called the no hair theorem. And you can
• 22:08
  Speaker 2: understand why I quite like that one. And the no
• 22:10
  Speaker 2: hair theorem basically tells you that you can't see very
• 22:14
  Speaker 2: much from the outside of a black hole, so you know,
• 22:19
  Speaker 2: like no hair just doesn't give you much of a
• 22:21
  Speaker 2: clue about what color somebody said it might have been.
• 22:24
  Speaker 2: I'm not quite pure where the term comes from. But
• 22:26
  Speaker 2: the no hair theorem is one that tells you that
• 22:28
  Speaker 2: there's very few parameters that you can measure outside the
• 22:31
  Speaker 2: black hole, though they're all much of a muchness accepting
• 22:35
  Speaker 2: their mass.
• 22:36
  Speaker 1: Okay, interesting, all right, there is It is another story
• 22:40
  Speaker 1: on fizit dot org. Phy s as I keep reminding you,
• 22:44
  Speaker 1: and yeah, fascinating, an unusual event. It's a space nuts.
• 22:49
  Speaker 1: Andrew Dunkley and Professor Fret Watson here space nuts to
• 22:58
  Speaker 1: our final story. Fred, We're going to look at your ainus.
• 23:02
  Speaker 1: No we're not. We don't want to do that, but
• 23:03
  Speaker 1: we are going to look at the planet. And sorry
• 23:07
  Speaker 1: I couldn't but any opportunity. This is really interesting though,
• 23:12
  Speaker 1: because when Voyager two, which is the only spacecraft that's
• 23:17
  Speaker 1: visited Uranus as far as I'm aware, went by, took
• 23:22
  Speaker 1: measurements and sent the data back and we all went, oh,
• 23:25
  Speaker 1: my gosh, this is unusual. How interesting. Wow. Now they've
• 23:28
  Speaker 1: revisited the data and gone, oh, hang on a minute,
• 23:32
  Speaker 1: if it had arrived, If it had arrived this, I
• 23:35
  Speaker 1: love this bit. Two days earlier, the readings would have
• 23:39
  Speaker 1: been completely different. This is a really fascinating story.
• 23:45
  Speaker 2: I think so too. And you know, we've always thought
• 23:49
  Speaker 2: Urinus was a bit peculiar. I mean it's peculiar because
• 23:52
  Speaker 2: it's lying on its side, it's rotates. For this, it's
• 23:57
  Speaker 2: north pool just below the plane of its orbit, which
• 23:59
  Speaker 2: means it's tipped over by about ninety eight I think degrees,
• 24:03
  Speaker 2: and that probably is the result of a collision at
• 24:06
  Speaker 2: some time in its past history, but it's also had
• 24:11
  Speaker 2: other aspects that have puzzled astronomers, very very odd magnetosphere.
• 24:19
  Speaker 2: So the magnetosphere is the is the region around a
• 24:22
  Speaker 2: planet which is dominated by its own magnetism, and the
• 24:27
  Speaker 2: magnetosphere has been thought to be highly asymmetric, very unusual
• 24:33
  Speaker 2: in shape, and to have strange, you know, the the
• 24:41
  Speaker 2: phenomena to do with the moons of Uranus have thought
• 24:44
  Speaker 2: to be have thought thought to be unusual that there
• 24:50
  Speaker 2: was no evidence, for example, of there being any kind
• 24:54
  Speaker 2: of ice, you know, the conventional ice moon idea. The
• 25:05
  Speaker 2: reason for that is that you detect the subi is
• 25:08
  Speaker 2: ocean of a moon by its magnetism, by sensing it
• 25:13
  Speaker 2: with a magnetometer, and if you can't detect it, then
• 25:17
  Speaker 2: you suspect there isn't any ocean, whereas in the case
• 25:22
  Speaker 2: of Uranus. It now I thought that because the magnetic
• 25:27
  Speaker 2: bubble that the planet lives in was highly distorted, maybe
• 25:31
  Speaker 2: that interpretation was wrong. And as you said, if it
• 25:36
  Speaker 2: had arrived two days earlier, we would probably have had
• 25:39
  Speaker 2: a better idea of what was going on. And the
• 25:41
  Speaker 2: reason why that two days is important is because of
• 25:45
  Speaker 2: a solar flare, an emission of plasma from the Sun
• 25:49
  Speaker 2: that reached Uranus kind of just before, just before Voyager
• 25:55
  Speaker 2: two got there, and totally distorted the magnetic bubble in
• 26:00
  Speaker 2: which the planet lives, so really, very very you know,
• 26:06
  Speaker 2: an unusual and perhaps misleading set of observations were or
• 26:13
  Speaker 2: deductions were made from the Voyager two data, which with
• 26:17
  Speaker 2: hindsight might be incorrect. And that hindsight is coming about
• 26:23
  Speaker 2: because people are reanalyzing the data of Voyager two. Is
• 26:27
  Speaker 2: something that I think is great that we constantly look
• 26:30
  Speaker 2: back at what we might call old data old information,
• 26:34
  Speaker 2: and you can learn new things from it. And there's
• 26:39
  Speaker 2: a comment, sorry, a comment by one of the great
• 26:42
  Speaker 2: planetary scientists of the present day who works at JPL
• 26:49
  Speaker 2: and is somebody that we know, Linda Spilker. She was
• 26:52
  Speaker 2: the project scientist for the Cassini space mission, but back
• 26:56
  Speaker 2: in the day she was also among the Voyager two
• 26:59
  Speaker 2: mission signsists when the flyby took place in nineteen eighty six,
• 27:06
  Speaker 2: the flyby of Uranus, And there's a nice quote from
• 27:10
  Speaker 2: her again in one of the articles that we've been
• 27:12
  Speaker 2: looking at. She says the flyby was packed with surprises,
• 27:17
  Speaker 2: and we were searching for an explanation of its unusual behavior.
• 27:20
  Speaker 2: The magnetosphere of Voyager two measured was only a snapshot
• 27:24
  Speaker 2: in time, and this new work explained some of the
• 27:27
  Speaker 2: apparent contradictions and it will change our view of uranus
• 27:30
  Speaker 2: once again. So she's commenting on this new research. A
• 27:33
  Speaker 2: veteran observer, very interesting person who was a delight to
• 27:38
  Speaker 2: host back in whatever year it was, might be twenty seventeen,
• 27:41
  Speaker 2: I think for yeah, I think it was twenty seventeen.
• 27:45
  Speaker 2: Just after the end of the mission, this Cassini mission,
• 27:49
  Speaker 2: she gave our Alison Levick lecture here in Sydney, So
• 27:52
  Speaker 2: that's how we got to know her.
• 27:54
  Speaker 1: Yes, of course, behind closed doors, everyone's going back to
• 27:57
  Speaker 1: the original team that oversaw Voyager two and said you
• 28:00
  Speaker 1: had one job.
• 28:03
  Speaker 2: Yeah, maybe that's right. On the other hand, you know,
• 28:07
  Speaker 2: research is like that. Sometimes you bark up the wrong
• 28:10
  Speaker 2: tree for decades, as we've seen yet.
• 28:13
  Speaker 1: What it's proven, though, is that uranus is ordinary. You know,
• 28:18
  Speaker 1: it's more thought it was. That's right, Yeah, more ordinary
• 28:22
  Speaker 1: than we thought it was. You it's like the other
• 28:23
  Speaker 1: gass giants in that respect, But in other ways it
• 28:26
  Speaker 1: is quite unusual and unique deed. Yeah, there's a great
• 28:31
  Speaker 1: article on that at cosmosmagazine dot com if you wanted
• 28:35
  Speaker 1: to check it out. That's where we're going to end things. Fred,
• 28:38
  Speaker 1: thank you very much.
• 28:41
  Speaker 2: Thank you Andrew. It's been a delight to talk as always.
• 28:44
  Speaker 1: Yes, yes, I like talking to you. My wife find
• 28:47
  Speaker 1: talked to me, but talk to you. I don't know
• 28:50
  Speaker 1: what's going on me, but anyway.
• 28:52
  Speaker 2: We'll.
• 28:56
  Speaker 1: We will see you next time. Fred, Thank you very much.
• 28:58
  Speaker 2: I hope so. Yeah.
• 29:03
  Speaker 1: Fred wants an astronomer at large and Hugh in the studio.
• 29:07
  Speaker 1: What was h up to today? Nothing? Didn't help us,
• 29:12
  Speaker 1: didn't help his wife, didn't pick up the kids from school,
• 29:15
  Speaker 1: didn't do anything. That's that's Hugh. Although we're getting I
• 29:21
  Speaker 1: must say, we're getting a lot of emails from people
• 29:23
  Speaker 1: saying can't it be nice to Hugh No, and from
• 29:28
  Speaker 1: me Andrew Dunkley. Thanks to your company. See you on
• 29:30
  Speaker 1: the next episode of Space Nuts. Bye Byepacenuts. You'll be
• 29:35
  Speaker 1: listening to the Space Nuts podcast available at Apple Podcasts, Spotify,
• 29:41
  Speaker 1: iHeart Radio, or your favorite podcast player. You can also
• 29:45
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• 29:49
  Speaker 1: another quality podcast production from nights dot com