Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #460: Gravity Reimagined, Quantum Field Fables & Black Hole Mysteries

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#460: Gravity Reimagined, Quantum Field Fables & Black Hole Mysteries · Space Nuts: Astronomy Insights & Cosmic Discoveries

• 0:00
  Speaker 1: Hi there, thanks for joining us on a Q and
• 0:02
  Speaker 1: A edition of Space Nuts. My name is Andrew Dunkley.
• 0:06
  Speaker 1: Coming up, we will be looking at gravity. Is it
• 0:10
  Speaker 1: working backwards and we don't know it? We'll answer that question,
• 0:14
  Speaker 1: quantum fields, ultra massive black holes, getting up close and
• 0:18
  Speaker 1: personal with telescopes.
• 0:20
  Speaker 2: Is it possible? And a very.
• 0:22
  Speaker 1: Interesting surprise at the end from one of our regular
• 0:25
  Speaker 1: sender in aurs, who's well, I'll preempt it by saying
• 0:29
  Speaker 1: I think it's a joke.
• 0:31
  Speaker 2: You figure it out for yourself.
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  Speaker 1: That's all coming up on this episode of Space Nuts.
• 0:36
  Speaker 3: Fifteen seconds in Channel ten nine ignition Figunch Space Nuts
• 0:45
  Speaker 3: or three two.
• 0:48
  Speaker 4: One Space Notes.
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  Speaker 5: As an I report it neils good.
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  Speaker 1: And it's always good to have the presence of Professor
• 0:57
  Speaker 1: Fred Watson, Astronomer at Large.
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  Speaker 2: Hello Fred, Hello Andrew.
• 1:01
  Speaker 5: Yes, it's good to have your presence too, because without
• 1:03
  Speaker 5: that I'd be sunk.
• 1:05
  Speaker 1: Yeah, well, I'd be twiddling my thumbs and you'd be
• 1:08
  Speaker 1: talking to yourself.
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  Speaker 2: All yeah.
• 1:14
  Speaker 1: Let's get straight into some questions, and we've got a
• 1:18
  Speaker 1: whole bunch. But and some of this might sound familiar
• 1:22
  Speaker 1: because people keep coming back to topics we've discussed and
• 1:25
  Speaker 1: asking questions about questions that we've answered, and that's fine.
• 1:29
  Speaker 1: I mean, it keeps the conversation going, and obviously, you know,
• 1:34
  Speaker 1: people are very interested in a lot of these topics.
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  Speaker 1: This first question comes from Carrick, Hello, Space Nuts, sending
• 1:42
  Speaker 1: this question from Wungari, New Zealand. I hope I pronounced
• 1:46
  Speaker 1: that correctly. I was pondering gravity and dark matter recently
• 1:50
  Speaker 1: and had a thought. We understand gravity as a force
• 1:53
  Speaker 1: that pulls us into objects with mass. However, is it
• 1:58
  Speaker 1: not possible that this attraction force is not there at
• 2:01
  Speaker 1: all and is replaced by a force that is rather
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  Speaker 1: pushing us away.
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  Speaker 2: Into objects with mass.
• 2:08
  Speaker 1: My thinking behind this started from the fact that our
• 2:11
  Speaker 1: known universe is expanding at an accelerated rate, and the
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  Speaker 1: cause behind this unknown energy or force is dark energy.
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  Speaker 1: Even as we experience this on Earth, rather than being
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  Speaker 1: attracted towards the center of our Earth, are we rather
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  Speaker 1: repelled by the forces towards Earth. Thanks for taking the
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  Speaker 1: time to read this, Carrick. Thanks Carrick. That turns the
• 2:37
  Speaker 1: whole gravity theory upside down.
• 2:39
  Speaker 5: Fred, Yeah, it's so. I mean, in a way, it's
• 2:46
  Speaker 5: a legitimate way of looking at gravity. It goes to
• 2:52
  Speaker 5: something we were talking about in the last episode. If
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  Speaker 5: you look at Einstein's relativity, which is probably the best, well,
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  Speaker 5: it is the best theory of gravity we have, uh,
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  Speaker 5: and imagine what a massive body does were we can
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  Speaker 5: only illustrate it in two dimensions because we haven't got
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  Speaker 5: three dimensional cartoons for this sort of thing. But it's
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  Speaker 5: always the picture of something solid like a planet sitting
• 3:22
  Speaker 5: on a basically a trampoline sheet which it's bending and
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  Speaker 5: pulling down to the middle, so that what you've got
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  Speaker 5: is a representative, a representation there of the shape of space,
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  Speaker 5: and it's the massive object that is causing the distortion
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  Speaker 5: of space, and that puts a slope, puts an incline
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  Speaker 5: onto the shape of space. So from our experience here
• 3:51
  Speaker 5: on Earth, if we're standing on the planet's surface, the
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  Speaker 5: shape of space is slightly different at our head from
• 3:57
  Speaker 5: what it is at our feet.
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  Speaker 2: Could could would.
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  Speaker 1: That be demonstrated? And this is just my brain thinking
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  Speaker 1: the same way a ship displaces water, is that.
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  Speaker 2: The same kind of effect?
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  Speaker 5: So well that if you if you've got a ship
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  Speaker 5: displacing water, basically put the ship in the water and
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  Speaker 5: the water moves away, And so that's a sort of
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  Speaker 5: static thing. With gravity, what you've got is a bending
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  Speaker 5: of the surface. Now, shipping water doesn't bend.
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  Speaker 1: It does for a bit, right, I say, But with
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  Speaker 1: with with the space itself, that bending stays, stays there.
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  Speaker 5: Space bends in response to matter, no matter what it is.
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  Speaker 5: And you could so you know, what Charac says is correct,
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  Speaker 5: You could equally well, given that scenario of the planet
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  Speaker 5: sitting on a trampoline and distorting the surface, you could
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  Speaker 5: equally well think of that as being something that's pushing,
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  Speaker 5: that's pushing you from the outside, because it's effectively the
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  Speaker 5: same thing that. The bottom line is that space is
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  Speaker 5: being distorted by gravity, and we feel that as a pool.
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  Speaker 5: But equivalently, we could call it a push from the
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  Speaker 5: outside because it has the same effect. So relativity that's
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  Speaker 5: sort of in some ways leading to that effect. The
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  Speaker 5: bottom line though, and I guess the focus of you know,
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  Speaker 5: the thought trail that Carrick was pursuing there is that, yes,
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  Speaker 5: we understand all that, and that all works, but dark
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  Speaker 5: matter and dark energy are both things on top of
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  Speaker 5: that that actually affect They do affect the shape of
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  Speaker 5: space in their own different way, but it's not the
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  Speaker 5: same as just normal gravity, which is very predictable and
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  Speaker 5: very understandable.
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  Speaker 4: So I don't think we could use that notion.
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  Speaker 5: As any kind of vehic four illuminating what dark master
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  Speaker 5: and dark energy are. That's got to come from the
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  Speaker 5: work that's already aging.
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  Speaker 4: I think so physics, of course.
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  Speaker 1: But his idea does hold a little bit of water
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  Speaker 1: in terms of the Earth. Is you know, sitting on
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  Speaker 1: the trampoline and the trampoline's pushing back.
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  Speaker 5: Yes, that's right in a way. That's that's correct. So
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  Speaker 5: that you know, anything coming from from the outside edge
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  Speaker 5: of the trampoline, you're all a marble down it or something.
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  Speaker 5: You could equally well say, well that that it's the
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  Speaker 5: outside that's pushing the marble in rather than the gravitational
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  Speaker 5: musk that's pulling it in. And it's because relativity tells
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  Speaker 5: us that it's the shape of space that has changed.
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  Speaker 2: There you go, all right, there you go, Carrick. You
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  Speaker 2: you weren't far off the mark.
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  Speaker 1: Can't wait to read the scientific paper you're now going
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  Speaker 1: to write for us? Yes, okay, we'll move on and
• 6:59
  Speaker 1: hello where everyone in New Zealand, beautiful country? Been there
• 7:02
  Speaker 1: a couple of times? Would go back tomorrow, but not
• 7:05
  Speaker 1: to watch rugby.
• 7:07
  Speaker 2: Now.
• 7:08
  Speaker 1: Next question comes from any in California or any writes
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  Speaker 1: to us fairly regularly. How do quantum fields behave Do
• 7:15
  Speaker 1: they interact with each other in any way? Take, for instance,
• 7:19
  Speaker 1: makenetic field with the Higgs field. You might need to
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  Speaker 1: elaborate on that a bit for it.
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  Speaker 5: Yeah, So quantum fields are the equivalent of sub atomic particles.
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  Speaker 5: And this is where you know quantum theory gets a
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  Speaker 5: bit weird because you can think of a sub atomic
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  Speaker 5: particle in two different ways, in fact three different ways actually,
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  Speaker 5: because you can think of it as a particle, you know,
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  Speaker 5: something like a golf ball, just to draw an analogue
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  Speaker 5: that would be familiar.
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  Speaker 4: To you, Andrew.
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  Speaker 5: Or you could think of it as a wave because
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  Speaker 5: particles and waves are equivalent. Or you can think of
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  Speaker 5: it as a field because of the field is equivalent.
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  Speaker 5: And by a field, I mean kind of what we're
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  Speaker 5: just talking about in terms of gravity. That bent, a
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  Speaker 5: distorted trampoline sheet.
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  Speaker 4: Is a field.
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  Speaker 5: If it's if it's a representation of space, then it's
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  Speaker 5: a field. It's a field caused by gravity. So Renny's
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  Speaker 5: question is how these fields interact and some of them,
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  Speaker 5: certainly do. But a magnetic field probably doesn't interact with
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  Speaker 5: a Higgs field. And look, I'm not a quantum field
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  Speaker 5: theorist by any means, as anybody who is listening to this.
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  Speaker 4: Will immediately realize.
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  Speaker 5: But magnetism is well, it's the electromagnetic force, the electromagnetic field,
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  Speaker 5: and that electromagnetic field, when you turn it into a particle,
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  Speaker 5: it becomes it is a photon. The photon is the
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  Speaker 5: is the particle equivalent of the electromagnetic field. And a
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  Speaker 5: photon does not have a rest mass. It's got a
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  Speaker 5: mass but on it because of its energy as it moves,
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  Speaker 5: it doesn't have a rest mass. And the Higgs field
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  Speaker 5: is what imparts the rest mass to other particles. So
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  Speaker 5: my guess is, and it is just a guess here, Andrew,
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  Speaker 5: that the magnetism does not interact with the Higgs field.
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  Speaker 5: But I think some of the other particles would, do,
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  Speaker 5: you know, the the other fundamental particles would interact with
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  Speaker 5: one another because their fields do.
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  Speaker 2: Okay, right, thanks for that.
• 9:43
  Speaker 4: Ready, Yeah, look he.
• 9:44
  Speaker 1: Comes up with some real pearls questions questions. Yeah, you
• 9:48
  Speaker 1: must you must have, you know, a very quick mind
• 9:53
  Speaker 1: ready to come up with these questions. He puts a
• 9:55
  Speaker 1: lot of thought into them, and you know, some of
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  Speaker 1: them are really clever, really clever.
• 10:01
  Speaker 2: Good to hear from you, Rennie. Keep them coming.
• 10:03
  Speaker 1: I know we've got a couple more in storage that
• 10:04
  Speaker 1: we'll pluck out sooner or later an answer down the track,
• 10:09
  Speaker 1: but yeah, good to hear from you.
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  Speaker 2: As always.
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  Speaker 1: This is space Nuts Andrew Unkley here.
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  Speaker 2: With Professor Fred Watson.
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  Speaker 4: Pace puts now.
• 10:22
  Speaker 1: Fred another regular contributor, and we didn't hear from him
• 10:27
  Speaker 1: too long ago, but he always seems to like Rennie,
• 10:31
  Speaker 1: come up with a few curveballs for us.
• 10:33
  Speaker 6: It's Rusty and Donnybrook. Rusty and Donnybrook wondering would an
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  Speaker 6: ultra massive black hole near the center of a large
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  Speaker 6: void be revealed by its gravitational lensing of more distant
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  Speaker 6: of distant galaxies.
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  Speaker 1: Kept it short and sweet. Okay, so did you catch
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  Speaker 1: that for it?
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  Speaker 5: I did, and I've got a short spe answer.
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  Speaker 2: Yes, kid will elaborate. Yeah.
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  Speaker 5: So, so everything acts as a gravitational lens no matter
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  Speaker 5: what it is, including the Earth. There have been ideas
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  Speaker 5: proposed of putting a spacecraft that the focus of the
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  Speaker 5: gravitational lens represented.
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  Speaker 4: By the Earth.
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  Speaker 5: I think I can't remember where it is a long way off.
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  Speaker 2: Yeah, I can imagine what points.
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  Speaker 5: But so so the you know it, any object will
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  Speaker 5: will distort things behind the sun. The classic example and
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  Speaker 5: the fact that when the eclipse of nineteen nineteen was observed,
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  Speaker 5: the stars of the Hyades, which happened to be behind
• 11:56
  Speaker 5: the Sun at that time, were distorted in their positions
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  Speaker 5: by the potational effect of the Sun.
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  Speaker 2: And so.
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  Speaker 5: Gravitational lensing is a property.
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  Speaker 4: Of all objects.
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  Speaker 5: A human would do it if we're in space, so yeah,
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  Speaker 5: a supermassive black hole is going to do it. The
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  Speaker 5: issue might well be, though, if the black hole is
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  Speaker 5: an active one, that's to say, it's gobbling up stuff
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  Speaker 5: around it and radiating, it might be quite difficult to
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  Speaker 5: see the stuff behind it because we've got, you know,
• 12:28
  Speaker 5: we'd have an accretion disc which is glowing, and as
• 12:32
  Speaker 5: we know from the event horizon telescope, that will be radiating.
• 12:35
  Speaker 4: And we're be able to see the accretion disc.
• 12:37
  Speaker 6: So yeah, it's.
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  Speaker 5: Something that would happen, but might be very difficult to detect.
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  Speaker 1: Okay, all right, thank you Rusty as always, and I'm
• 12:48
  Speaker 1: sure he'll send in more questions because he does he
• 12:52
  Speaker 1: just does. But he's another one that probably spends a
• 12:56
  Speaker 1: lot of time contemplating these things. We had Rusty on
• 12:58
  Speaker 1: as a special guest some time ago and we got
• 13:04
  Speaker 1: all these questions out of his system, but then he
• 13:06
  Speaker 1: came back.
• 13:08
  Speaker 2: Come out with plenty more.
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  Speaker 1: Next question comes from David. If the James Webb telescope
• 13:16
  Speaker 1: can see so far into the past with such great detail,
• 13:20
  Speaker 1: why can't we have a telescope where we can see
• 13:23
  Speaker 1: every grain of sand on the moon or do we?
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  Speaker 2: Thank you?
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  Speaker 1: David, I must confess I've wondered the same thing.
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  Speaker 4: Good. Well, I'm here to tell you why.
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  Speaker 2: I'm guessing there's a reason why not.
• 13:39
  Speaker 5: Yeah, there is, and it's all about so the ability
• 13:44
  Speaker 5: of a telescope to see detail is something we call
• 13:48
  Speaker 5: in the trade. We call it the angular resolution, and
• 13:51
  Speaker 5: it's the angle on the sky that is the finest
• 13:57
  Speaker 5: detail that the telescope can reveal.
• 14:01
  Speaker 4: With the angle.
• 14:02
  Speaker 5: Australian telescope here on in northwestern New South Wales a
• 14:07
  Speaker 5: four meter angle Australian telescope three point nine meters. The
• 14:10
  Speaker 5: one I was stronggering charge off for a while that
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  Speaker 5: if you put it in space would resolve detail on
• 14:17
  Speaker 5: the scale of the thirtieth of an arcsecond. Now, an
• 14:19
  Speaker 5: arcsecond is is the angle made by basically a dime
• 14:24
  Speaker 5: or a one dollar coin at a distance of five
• 14:26
  Speaker 5: kilometers about three miles. It's a tiny angle. The at
• 14:32
  Speaker 5: in space could resolve a thirtieth of that, something like
• 14:36
  Speaker 5: a thirtieth of an arcsecond. So the bottom line, however,
• 14:41
  Speaker 5: is that because we're sitting at the bottom of an
• 14:43
  Speaker 5: atmosphere that's quite turbulent, the very best you can do
• 14:47
  Speaker 5: is about ero point nine of an arcsecond on a
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  Speaker 5: really exquisite night, and that would be the angle, the
• 14:53
  Speaker 5: minimal I Goode that you would be able to resolve. Now,
• 14:56
  Speaker 5: James Web telescope is a six point five meter tell
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  Speaker 5: it's bigger than our angle Australian telescope, which is for
• 15:04
  Speaker 5: me says I just said three point nine meters.
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  Speaker 4: And the.
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  Speaker 5: Sensitivity to detail depends linearly actually on the diameter of
• 15:16
  Speaker 5: the telescope. So the bigger the telescope, the finer the detail.
• 15:19
  Speaker 4: You can see.
• 15:20
  Speaker 5: So with it James Web telescope, the finest detail it
• 15:25
  Speaker 5: can see is point zero six eight of an arcsecond,
• 15:30
  Speaker 5: a little bit less finer than a tenth of an arcsecond.
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  Speaker 2: Is that because?
• 15:39
  Speaker 1: Is that because of its size and the fact that
• 15:41
  Speaker 1: it's not being disrupted by a setmasphy.
• 15:44
  Speaker 5: That's correct, that's right, that's correct. It's sixty eight milliarc seconds,
• 15:48
  Speaker 5: Is that right?
• 15:49
  Speaker 4: Yes?
• 15:49
  Speaker 5: Point zero six eight it's quite a bit less than
• 15:53
  Speaker 5: a tenth actually. Anyway, the bottom line is that's the
• 15:57
  Speaker 5: finest detail that the telescope can resolve. Put it anywhere else,
• 16:02
  Speaker 5: and you know, you can point it anywhere in the universe,
• 16:06
  Speaker 5: this is what I'm trying to say, and you will
• 16:08
  Speaker 5: get that same resolution to detail. Whether it's distant galaxies,
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  Speaker 5: whether it's the planets, whether it's exoplanets, you will get
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  Speaker 5: the same fineness of detail. So what happens if you
• 16:21
  Speaker 5: point it to the Moon? You get you get a
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  Speaker 5: resolution of point zero six eight millie sorry, point zero
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  Speaker 5: six eight arcseconds. What does that show you at the
• 16:32
  Speaker 5: distance of the Moon. It will show you details on
• 16:36
  Speaker 5: a scale of one hundred and twenty six meters. That's
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  Speaker 5: the finest thing that you could see on the Moon
• 16:43
  Speaker 5: with the web telescope.
• 16:44
  Speaker 4: And it's quite big.
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  Speaker 5: It's not grains of sand, it's one hundred and twenty
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  Speaker 5: six meters. It's a big object, and that's because the
• 16:51
  Speaker 5: Moon's a long way away, three hundred and eighty four
• 16:54
  Speaker 5: thousand kilometers.
• 16:56
  Speaker 1: So okay, do you think that the day may come
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  Speaker 1: with it I'll build a bigger and better telescope that
• 17:02
  Speaker 1: may be capable of much more detail I'm going to envisage.
• 17:06
  Speaker 2: The answer is yes, well.
• 17:08
  Speaker 5: Yes, so that we already We already have that on
• 17:11
  Speaker 5: the stocks the thirty nine point three meter diameter e
• 17:16
  Speaker 5: l T the extremely large telescope being built at Cero
• 17:18
  Speaker 5: Homozonas in Chile. Now that telescope is at the bottom
• 17:24
  Speaker 5: of the atmosphere, so it suffers from that. But it's
• 17:27
  Speaker 5: got a very very sophisticated system of adaptive optics on
• 17:31
  Speaker 5: board that will give it twenty times the detailed sensitivity.
• 17:35
  Speaker 4: Of the Hubble telescope.
• 17:37
  Speaker 2: Wow.
• 17:37
  Speaker 5: Remember the Leubble is not the gems Web but smaller,
• 17:41
  Speaker 5: so it's it's yeah, it's uh, it's a very fine
• 17:46
  Speaker 5: resolution machine. We still will only be seeing detail, you know,
• 17:53
  Speaker 5: on the scale of tens of meters on the Moon.
• 17:58
  Speaker 5: To imagine seeing rains of sad you probably need a
• 18:02
  Speaker 5: telescope bigger than the Earth. That worked out what it is,
• 18:05
  Speaker 5: and it's actually a lot easier just to set the
• 18:07
  Speaker 5: spacecraft with a cabrole. And that's how we've seen images
• 18:11
  Speaker 5: of all the Apollo landing sites because of Fluido Reconnoissance orbiter,
• 18:15
  Speaker 5: which is photographing it from thirty or fifty kilometers above
• 18:19
  Speaker 5: the surface.
• 18:20
  Speaker 2: Yeah.
• 18:21
  Speaker 1: I was sort of HARKing back to the sixties in
• 18:24
  Speaker 1: the early seventies.
• 18:25
  Speaker 2: With the Moon missions.
• 18:27
  Speaker 1: After they were all complete, of course, three gazillion books
• 18:30
  Speaker 1: were released, and I got one that was aimed more
• 18:33
  Speaker 1: at younger people. And even though back then we only
• 18:37
  Speaker 1: had black and white television. Yes, kids, it's true, we
• 18:40
  Speaker 1: only had black and white television and the pictures were
• 18:44
  Speaker 1: quite fuzzy, the book was mind blowingly beautiful. The image images,
• 18:53
  Speaker 1: as I recall from that book, was so high definition
• 18:56
  Speaker 1: compared to what we could see on TV. I was
• 18:59
  Speaker 1: absolutely blown away by it. Yeah. So even then, the
• 19:04
  Speaker 1: cameras that they had on the Moon were quite quite brilliant.
• 19:09
  Speaker 1: But when they go back and start walking around up
• 19:12
  Speaker 1: there again, I can't imagine what the pictures are going
• 19:16
  Speaker 1: to be like with modern day equipment. It's going to
• 19:19
  Speaker 1: be very exciting. And even the pictures coming back from
• 19:23
  Speaker 1: Mars so like death these days.
• 19:26
  Speaker 4: That's right, Yeah, fantastic.
• 19:28
  Speaker 5: I'm just going to revisit something I said Andrew, which
• 19:33
  Speaker 5: was about the Angle Australian telescope being able to resolve
• 19:36
  Speaker 5: for thirtieth of an arc second. That is assuming the
• 19:41
  Speaker 5: mirror is absolutely perfect with no flaws on it. So
• 19:46
  Speaker 5: in reality it will be slightly worse than that in space.
• 19:50
  Speaker 5: And that's why the figure that I mentioned for the
• 19:53
  Speaker 5: James Web telescope on zero six eight is sort of,
• 19:58
  Speaker 5: you know, sounds that it was worse than the.
• 20:00
  Speaker 4: Angle Australian telescope.
• 20:02
  Speaker 2: It's not.
• 20:02
  Speaker 5: It's much better, but that takes into account the imperfections
• 20:05
  Speaker 5: in the mirror as well. Whereas the value that I
• 20:09
  Speaker 5: quoted for the eighties is if the mirror was perfect,
• 20:11
  Speaker 5: if it was an absolutely perfect mirror, the only thing
• 20:14
  Speaker 5: that was limiting its ability to see detail was the
• 20:17
  Speaker 5: theory of diffraction.
• 20:20
  Speaker 2: Okay, Yeah, And just.
• 20:23
  Speaker 5: In case anybody who was listening carefully and said, wait
• 20:25
  Speaker 5: a minute, he just said something else.
• 20:30
  Speaker 1: I can't imagine what the badget is at a telescope
• 20:33
  Speaker 1: like the Anglo Australian for windex. I mean that must
• 20:37
  Speaker 1: cost a fortune.
• 20:39
  Speaker 5: You know.
• 20:42
  Speaker 4: The End Australian telescope.
• 20:45
  Speaker 5: Mirror is cleaned once a year when the aluminium surface
• 20:50
  Speaker 5: is removed and and it's requoated, right, so it's never
• 20:54
  Speaker 5: cleaned with chemicals. Some observatories avoid doing that by using
• 21:00
  Speaker 5: carbon dioxide snow home solid carbon dioxide across the mirror
• 21:04
  Speaker 5: and that takes away some of the dust. We don't
• 21:06
  Speaker 5: do that in the Angle Australian. We take the surface
• 21:08
  Speaker 5: away and recoat it. But just down the road from
• 21:13
  Speaker 5: the Angle Australian Telescope is the United Kingdom Schmidt telescope,
• 21:16
  Speaker 5: which I was also a strollery and Childe off yep.
• 21:19
  Speaker 5: That was at one point two meter diame. It a
• 21:21
  Speaker 5: lens at the front, not a mirror. It does have
• 21:23
  Speaker 5: a mirror in it, but the main thing that gets
• 21:26
  Speaker 5: dirty is a lens. And guess what we used to
• 21:29
  Speaker 5: clean it with wind as.
• 21:33
  Speaker 1: So you ask a dumb question, you get a great answer.
• 21:36
  Speaker 1: Sometimes sometimes it works. I was joking anyway, that's good,
• 21:42
  Speaker 1: that's good to know. Yeah, well, so no, it can't work, David.
• 21:49
  Speaker 2: It's just a bit beyond our capability and spread. Yeah yeah.
• 21:54
  Speaker 1: And you know, if you wanted to build one capable
• 21:57
  Speaker 1: of that, you might as well build a whole planet,
• 22:00
  Speaker 1: although that work, that works for Darth Vader. But yeah,
• 22:05
  Speaker 1: all right, thanks David, thanks for the question. One final thing,
• 22:08
  Speaker 1: it's not a question. It's one of our regular sender
• 22:11
  Speaker 1: ins who shall remain.
• 22:13
  Speaker 2: Nameless because he'll tell us who he is.
• 22:15
  Speaker 1: Anyway, This is kind of well, he's going to eventually
• 22:20
  Speaker 1: tell a joke, but you're gonna have to because he
• 22:25
  Speaker 1: bleeps part of it out. You're going to have to
• 22:28
  Speaker 1: use your brain to figure out the punchline. Some people
• 22:30
  Speaker 1: may already have heard this one. I love it is Martin.
• 22:35
  Speaker 7: Hello, Space Nights. Martin Berman Borvain here from Potomac, Maryland, US,
• 22:43
  Speaker 7: a writer extraordinaire in many genres, especially science fiction, and
• 22:50
  Speaker 7: I am currently working on a novel about an obnoxious
• 22:55
  Speaker 7: billionaire called Egon Risk and his plans to take a
• 23:02
  Speaker 7: starship full of dim witted celebrities to found a new
• 23:08
  Speaker 7: master race among the stars, and how these plans may
• 23:13
  Speaker 7: or may not come to grief. I don't actually have
• 23:17
  Speaker 7: a question this week. I actually just have a little
• 23:24
  Speaker 7: known bit of Star Wars trivia. Did you know that
• 23:29
  Speaker 7: George Lucas was originally planning to have Skywalker's home planet
• 23:37
  Speaker 7: Tattooing be a satellite of the seventh planet of our
• 23:45
  Speaker 7: solar system. Yes, but he had to move the planet
• 23:51
  Speaker 7: Tattooing to a long long time ago in a galaxy
• 23:57
  Speaker 7: far far away because someone pointed out to him that
• 24:02
  Speaker 7: his original plan would have resulted in a double planet
• 24:08
  Speaker 7: called Tattooing. Your plea, Okay, that's all the time we
• 24:15
  Speaker 7: have for dad jokes today, Bermin goorvain over and out out.
• 24:21
  Speaker 2: Oh Martin, Oh Martin, Martin, Matt, I love that joke, though,
• 24:25
  Speaker 2: I really do very clever.
• 24:28
  Speaker 1: Again a play on words, A play on words. It
• 24:33
  Speaker 1: has done the rounds a bit, but it's always worth retelling.
• 24:37
  Speaker 2: God on you, Martin.
• 24:37
  Speaker 1: If you've got a question for us, please jump on
• 24:39
  Speaker 1: our website and send it in. You can do that
• 24:42
  Speaker 1: by going to space Nuts podcast dot com and then
• 24:45
  Speaker 1: all you need to do is click on the AMA
• 24:48
  Speaker 1: tab at the top and it's a simple case of
• 24:53
  Speaker 1: just sending us a text question, or if you've got
• 24:58
  Speaker 1: a device with a microphone, you can send it an
• 25:00
  Speaker 1: audio question. As always, don't forget to tell us who
• 25:03
  Speaker 1: you are and where you're from, and we'd love to
• 25:05
  Speaker 1: hear from you, no matter how big, small, or insignificant
• 25:09
  Speaker 1: the question, we'll give it a crack and sometimes we
• 25:14
  Speaker 1: get very similar questions. So if we don't answer yours,
• 25:16
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• 25:21
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• 25:26
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• 25:30
  Speaker 1: We're all done, Fred, thank you as always.
• 25:33
  Speaker 5: Thank you Andrew. Good to talk to you, and we'll
• 25:36
  Speaker 5: catch up again soon.
• 25:37
  Speaker 2: I think we will.
• 25:39
  Speaker 1: Yes, Indeed, Professor Fred Watson, astronomer at large and here
• 25:42
  Speaker 1: in the studio who didn't ask us any questions today.
• 25:48
  Speaker 1: Very disappointing, but I'm sure that'll fix itself down the track.
• 25:54
  Speaker 1: From me Andrew Dunkley, thanks for your company. We'll catch
• 25:56
  Speaker 1: you again real soon on another episode of Space Nuts.
• 25:59
  Speaker 1: Bye bye spaces.
• 26:01
  Speaker 2: You'll be listening to the Space Nuts podcast.
• 26:05
  Speaker 1: Available at Apple Podcasts, Spotify, iHeartRadio, or your favorite podcast player.
• 26:11
  Speaker 1: You can also stream on demand at bites dot com.
• 26:15
  Speaker 6: This has been another quality podcast production from nights dot com.