Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #464: Dark Matter Dynamics, Spacecraft Synchronisation & Asteroid Belt Enigmas

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#464: Dark Matter Dynamics, Spacecraft Synchronisation & Asteroid Belt Enigmas · Space Nuts: Astronomy Insights & Cosmic Discoveries

• 0:00
  Speaker 1: Hi there, thanks for joining us. This is Space Nuts
• 0:02
  Speaker 1: Q and A where we answer audience questions, and on
• 0:06
  Speaker 1: this episode we're going to be talking about the relationship
• 0:09
  Speaker 1: between dark matter and the cosmic web. We'll also look
• 0:15
  Speaker 1: at an issue that's been raised about the synchronization of
• 0:19
  Speaker 1: communication between Earth and long distance spacecraft. How do they
• 0:24
  Speaker 1: do that because they're moving at rat of knots at
• 0:27
  Speaker 1: great distances away from us, so how do we talk
• 0:30
  Speaker 1: to them. There's also questions about whether or not there's
• 0:32
  Speaker 1: more than one asteroid belt and can we build a
• 0:36
  Speaker 1: space wheel. We'll tackle all that today on Space.
• 0:41
  Speaker 2: Nuts fifteen seconds guidance in Channal ten nine ignition.
• 0:47
  Speaker 1: Sequence Space Nuts or three two one Space Nuts.
• 0:55
  Speaker 3: As when I reported Bill's.
• 0:57
  Speaker 1: Good, here he is again, Fred. What's an hello? Fred? Hi, Andrew?
• 1:04
  Speaker 4: How are you?
• 1:05
  Speaker 1: I'm as good as the last time you saw me.
• 1:09
  Speaker 1: I'm even wearing the same shirt.
• 1:11
  Speaker 2: Strangely enough, it's extraordinary, isn't it, Soli?
• 1:14
  Speaker 1: What a coincidence? Amazing? Are you ready to tackle some questions?
• 1:21
  Speaker 4: Why not?
• 1:22
  Speaker 1: All right, let's get down to it now. Our first
• 1:25
  Speaker 1: question or questions come from the same source, and it's
• 1:31
  Speaker 1: Ben and he's got a couple of interesting ideas. He says, Hi,
• 1:37
  Speaker 1: there Andrew and Fred, longtime listener, but first time questioner
• 1:41
  Speaker 1: from Chicago, though originally from Australia. Just in the form
• 1:45
  Speaker 1: of a text as I'm one of the lucky sods
• 1:48
  Speaker 1: who's gotten COVID twice in two months and can't talk.
• 1:54
  Speaker 1: I'm sure some people can appreciate that. Just have two questions,
• 1:58
  Speaker 1: not related, and of course one is going to be
• 2:01
  Speaker 1: about dark matter. Fred mentioned in an episode that matter
• 2:05
  Speaker 1: and dark matter don't interact, and one way of seeing
• 2:09
  Speaker 1: that was some galaxies have moved over time, but the
• 2:14
  Speaker 1: blob of dark matter doesn't move with it, to paraphrase.
• 2:17
  Speaker 1: But if that's the case, my question is, how did
• 2:21
  Speaker 1: dark matter form the cosmic web pattern of the universe
• 2:24
  Speaker 1: in the first place. If it doesn't move, since galaxies
• 2:28
  Speaker 1: are theorized to be held together using dark matter, wouldn't
• 2:32
  Speaker 1: then wouldn't then moving off the dark matter blob mean
• 2:37
  Speaker 1: they would start to fly apart. That's his first question.
• 2:41
  Speaker 1: We'll get to the second one after we've solved.
• 2:43
  Speaker 2: That riddle thread So that the interaction there is an interaction,
• 2:50
  Speaker 2: which is via gravity. The least understood of all the
• 2:54
  Speaker 2: fundamental forces, and that's why you know, if you've got
• 2:59
  Speaker 2: a unif some baby universe that's got this web of
• 3:03
  Speaker 2: dark matter, because that dark matter has gravitational interaction, then
• 3:10
  Speaker 2: it will pull the normal matter in, so you do
• 3:13
  Speaker 2: get you know, the galaxies strong, all out, strong, out
• 3:15
  Speaker 2: along the cosmic web, as we find today when we
• 3:18
  Speaker 2: observe galaxy surveys and things of that sort. The point
• 3:22
  Speaker 2: I was making about the lack of interaction of other kinds,
• 3:27
  Speaker 2: in other words, that you know, they don't bounce off
• 3:29
  Speaker 2: one another. Was a couple of examples where we know
• 3:35
  Speaker 2: that clusters of galaxies, which are the biggest sort of
• 3:39
  Speaker 2: objects in the universe, they've collided and the gas and
• 3:45
  Speaker 2: stars in those galaxies have sort of ground to a
• 3:49
  Speaker 2: hole in the pile up. So what you end up
• 3:52
  Speaker 2: with is a big blob of galaxy debris, except it's
• 3:57
  Speaker 2: not debry. It's much the same as it was before
• 3:59
  Speaker 2: they interacting, but they're gravitationally probably pulling one of an
• 4:03
  Speaker 2: apart and.
• 4:03
  Speaker 4: Things like that.
• 4:04
  Speaker 2: So you've got two galaxy clusters, they collide, and you
• 4:08
  Speaker 2: get a smash up there, which you can identify as
• 4:11
  Speaker 2: being two different galaxy clusters colliding, but the dark matter
• 4:16
  Speaker 2: from each of those because each of those clusters would
• 4:20
  Speaker 2: have had its own dark matter halo. The dark matter
• 4:23
  Speaker 2: just carries on. It doesn't interact either apparently with itself
• 4:29
  Speaker 2: or with the debris the normal matter.
• 4:33
  Speaker 4: So what you've got is.
• 4:36
  Speaker 2: A scenario where you've got a new cluster of galaxies
• 4:40
  Speaker 2: that's been formed from the two colliding clusters, and on
• 4:43
  Speaker 2: either side of it is a blob of dark matter,
• 4:45
  Speaker 2: which is the dark matter from the two original clusters
• 4:48
  Speaker 2: that's just carried on going because it doesn't impact the
• 4:52
  Speaker 2: normal matter. It does gravitationally, so it'll tend to have
• 4:56
  Speaker 2: a gravitational influence on it, but the dark matter basically
• 4:59
  Speaker 2: just just carries on.
• 5:01
  Speaker 1: I'm very confusing for it. I can understand why we
• 5:05
  Speaker 1: get so many questions about it, because it just doesn't
• 5:08
  Speaker 1: seem to make sense.
• 5:11
  Speaker 4: No, So the only thing that makes sense.
• 5:14
  Speaker 2: Is that the particles of dark mutter normal matter door
• 5:19
  Speaker 2: sort of bounce off one another, but they do have
• 5:22
  Speaker 2: a gravitaxial effect on each other.
• 5:24
  Speaker 4: That's really the way to put it.
• 5:27
  Speaker 1: Okay, that makes it sound a little bit more simple,
• 5:29
  Speaker 1: I hope.
• 5:31
  Speaker 5: Now.
• 5:31
  Speaker 1: Ben's second question, which is for spacecraft Communicating with them
• 5:37
  Speaker 1: takes obviously longer and longer the further they are away,
• 5:41
  Speaker 1: with all the planets moving all the time along the
• 5:44
  Speaker 1: gravitational along with gravitational differences, the further or even closer
• 5:49
  Speaker 1: to other orbital bodies, how do we keep the spacecraft
• 5:53
  Speaker 1: synced to Earth perfectly? Would we, for spacecraft very far away,
• 5:57
  Speaker 1: have to pinpoint or point telescopes further ahead of where
• 6:03
  Speaker 1: they will be if it takes hours for the signal,
• 6:07
  Speaker 1: or if it's close to a body like the Parker
• 6:11
  Speaker 1: Solar probe. Would that not mess with the signals with
• 6:14
  Speaker 1: delays possible or possibly the signal bending somehow. I'm sure
• 6:19
  Speaker 1: these are taken into account, but I just wonder how
• 6:22
  Speaker 1: people plan for it. I know telescopes account for this
• 6:25
  Speaker 1: with redshift, but I wasn't sure how two way communication
• 6:30
  Speaker 1: with satellite probes works. That's a really interesting question because
• 6:36
  Speaker 1: we take for granted that we can still communicate with Voyager,
• 6:39
  Speaker 1: and it is way beyond anything else that we've sat
• 6:42
  Speaker 1: out so far.
• 6:45
  Speaker 2: Right, it's twenty two light hours away at the moment
• 6:47
  Speaker 2: I remember, Yeah, So yeah, it is a good question,
• 6:51
  Speaker 2: but it can all be compensated for, and in fact
• 6:58
  Speaker 2: the ben mentions the signals. And there's a classic case
• 7:06
  Speaker 2: of I think it was the Cassini spacecraft when it
• 7:09
  Speaker 2: was on its way to Saturn.
• 7:11
  Speaker 4: This is in the early two thousands.
• 7:14
  Speaker 2: It was at one point behind the Sun to us,
• 7:21
  Speaker 2: but we could still see the signals because they were
• 7:24
  Speaker 2: being bent by the gravitational effect of the Sun, just
• 7:29
  Speaker 2: like light is. You know, it's the general relativity says
• 7:33
  Speaker 2: that gravity will alter the direction of a beam of
• 7:36
  Speaker 2: light or a beam of radiation. Then that was one
• 7:39
  Speaker 2: of the ways. Actually, the Cassini observations of signals coming
• 7:44
  Speaker 2: from the you know, the spacecraft being on the backside
• 7:47
  Speaker 2: of the song but still being able to see the
• 7:49
  Speaker 2: signals was one of the again one of the confirmations
• 7:53
  Speaker 2: of gravitational deflection of light. Once again, you know, underpinning
• 8:01
  Speaker 2: relativities absolutely fundamental place, you know, understanding of the universe.
• 8:06
  Speaker 2: And yes, if you if you had a spacecraft that
• 8:09
  Speaker 2: was moving across our line of sight and occasionally they
• 8:13
  Speaker 2: are doing because they're you know, if you've got gravitational
• 8:16
  Speaker 2: sling shot maneuvers, that might well put the spacecraft on
• 8:20
  Speaker 2: the trajectory that's going across our line of sight. You
• 8:23
  Speaker 2: do need to aim your your radio telescope ahead of it.
• 8:26
  Speaker 2: You've got to you've got to take it into account,
• 8:28
  Speaker 2: and people do that and it's completely routine. So because
• 8:33
  Speaker 2: we understand what the orbits are doing, it's uh, it's
• 8:36
  Speaker 2: basically a routine, you know, a routine maneuver or maneuver
• 8:42
  Speaker 2: of telescope operations. Probably the person to talk to you
• 8:45
  Speaker 2: about this is Glenn Nagel, who looks after the Tidbin
• 8:49
  Speaker 2: Miller tracking station, one of NASA's deep space tracking network,
• 8:53
  Speaker 2: which is stop far from camera. I might talk to
• 8:57
  Speaker 2: him about it next time, I seeing.
• 8:59
  Speaker 1: Yeah, why not? So Ben was pretty spot on with
• 9:02
  Speaker 1: his salrus. Ben goes on to say thank you for
• 9:07
  Speaker 1: answering this rambling and for the wonderful podcast. He said,
• 9:11
  Speaker 1: I also worked for the ABC in Ultimo for a while.
• 9:15
  Speaker 1: That's in Sydney, so maybe we crossed paths Andrew and
• 9:18
  Speaker 1: never knew it. I was in the dark corner of
• 9:21
  Speaker 1: the newsroom, Ben. I never got to the newsroom much.
• 9:25
  Speaker 1: I think I actually only entered the newsroom once in
• 9:28
  Speaker 1: my life, and I could feel the tension the moment
• 9:33
  Speaker 1: or walked in. I know they talk about the atmosphere
• 9:37
  Speaker 1: of places creating certain awareness amongst humans. I've never felt
• 9:45
  Speaker 1: more intimidated than the Dale walked into the ABC Radio newsroom.
• 9:49
  Speaker 1: I could feel how I don't know how deep the
• 9:56
  Speaker 1: place was as an observer, and that's where they make
• 10:02
  Speaker 1: all the news and current affairs programs for ABC in
• 10:05
  Speaker 1: New South Wales. And I yeah, look, I don't envy
• 10:10
  Speaker 1: you being there. I couldn't have worked in that environment.
• 10:12
  Speaker 1: It was just too much for me. I liked my
• 10:15
  Speaker 1: little regional radio job out in the Sticks much more,
• 10:19
  Speaker 1: much more relaxed. Thank you, Ben. Great to hear from you,
• 10:24
  Speaker 1: and hope all is well in Chicago. This is Space
• 10:26
  Speaker 1: Nuts with Andrew Dugley and Professor Fred Watson Space Buds.
• 10:35
  Speaker 1: Let's get some audio questions sorted out. Fred, and one
• 10:40
  Speaker 1: of our regular sender inters is Sandy from I'm going
• 10:43
  Speaker 1: to say Melbourne. I said that last time when I
• 10:45
  Speaker 1: was wrong was a Brisbane I don't know Sandy somewhere my.
• 10:48
  Speaker 6: Fred, Sandy from Melbourne a game. My question today is
• 10:53
  Speaker 6: about the asteroid belts between Mars and Jupiter. As I understand,
• 10:58
  Speaker 6: that's where the the primary asteroid belts are now, is
• 11:05
  Speaker 6: there any other asteroid belts that's past the orbit of Jupiter,
• 11:09
  Speaker 6: so I'm preferring to perhaps out towards Neptune that sort
• 11:13
  Speaker 6: of or.
• 11:15
  Speaker 1: Uranus sort of sort of distance.
• 11:19
  Speaker 6: I'm assuming the answer is known, And if the answer
• 11:23
  Speaker 6: is no, how come they've sort of massed together between
• 11:28
  Speaker 6: Jupteri Mars and not further out.
• 11:31
  Speaker 1: Thank you, Thanks Sandy. If you've got asteroids around Uranus,
• 11:34
  Speaker 1: I think you should the doctor. But they're more likely
• 11:37
  Speaker 1: to be emerhoids. Sorry I couldn't help it. Yeah, yeah,
• 11:44
  Speaker 1: and look, I like the question because my first thought
• 11:47
  Speaker 1: is we'll hang on the asteroid belt, yes, know all
• 11:50
  Speaker 1: about that. Is there another one out there? And I
• 11:52
  Speaker 1: just thought, well, it's the Kuiper Belt, but is not
• 11:54
  Speaker 1: the same, is it? Or is it the same? Yeah?
• 12:00
  Speaker 4: Right, Andrew.
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  Speaker 2: It's true that there are other asteroid belts, and they're
• 12:05
  Speaker 2: quite different in character. So Sad is right that the
• 12:12
  Speaker 2: main asteroid belt is the one and the most highly populated,
• 12:17
  Speaker 2: is the one that lies between the orbits of Mars
• 12:20
  Speaker 2: and Jupiter, and that's been known about since the early
• 12:25
  Speaker 2: nineteenth century. The first one of those series was discovered
• 12:29
  Speaker 2: on the first of January eighteen hundred and one, and
• 12:32
  Speaker 2: that set the pass for you know the understanding that
• 12:36
  Speaker 2: there is a belt of small objects between between Mars
• 12:40
  Speaker 2: and Jupiter. We used to call them minor planets. In fact,
• 12:42
  Speaker 2: when my MSc thesis is called the determination of minor
• 12:46
  Speaker 2: planet orbits where you go. So that's what we now
• 12:52
  Speaker 2: call the main asteroid belt. Actually, Sunday is right because
• 12:55
  Speaker 2: he's talked about it as being multiple belts, and in
• 12:58
  Speaker 2: a way there are different families is within those asteroid belts,
• 13:02
  Speaker 2: within that main asteroid belt, if I put it that way.
• 13:06
  Speaker 2: We talked about some of those in the last episode
• 13:08
  Speaker 2: of Space Notes. Now as regards other asteroid belts, yes
• 13:13
  Speaker 2: there are, and as you said, Andrew, the Kliper Belt
• 13:18
  Speaker 2: is what really comes to mind. And that's just one
• 13:21
  Speaker 2: of a number of different groups of icy asteroids which
• 13:25
  Speaker 2: are beyond the orbit of Neptune, which is why they
• 13:27
  Speaker 2: called trans Neptunian objects. One of the bigger ones is
• 13:31
  Speaker 2: called Pluto, but it is just one of the bigger ones,
• 13:35
  Speaker 2: and there are different families within that group of transit
• 13:41
  Speaker 2: Tunian objects. There are objects called classical Coiper belt objects.
• 13:46
  Speaker 2: There are objects called resonant objects where they have a
• 13:50
  Speaker 2: resonance with the orbit of Neptune. And then the most
• 13:53
  Speaker 2: distant ones are called scattered disc objects. So these are
• 13:57
  Speaker 2: three different groups of objects which are in that to
• 14:00
  Speaker 2: asteroid belt. They have a different formation we think from
• 14:06
  Speaker 2: from the inner asteroid belt, because mostly I see those
• 14:10
  Speaker 2: objects as we know blue toys, and that means that
• 14:14
  Speaker 2: what we're seeing is a family of objects that really
• 14:18
  Speaker 2: are the remnants of the of the of the cloud
• 14:21
  Speaker 2: of dust and gas from which the Solar System formed.
• 14:24
  Speaker 2: It's the outer extremities, objects that have never been warmed
• 14:28
  Speaker 2: up by the Sun, the star that formed in the middle,
• 14:32
  Speaker 2: whereas the asteroid belt is principally rocky objects, and we
• 14:36
  Speaker 2: think it's just a sort of cloud of debris that's
• 14:40
  Speaker 2: been shepherd in into that particular orbit between Mars and
• 14:43
  Speaker 2: Jupiter by the huge gravitational pool of Jupiter. Jupiter's gravitational
• 14:49
  Speaker 2: influence is enormous on the other planets and the minor planets,
• 14:53
  Speaker 2: and we think that's what it is. There's a region
• 14:56
  Speaker 2: between Mars and Jupiter where debris is collected and probably
• 15:00
  Speaker 2: it's still primordial damer it's the rocky material from which
• 15:03
  Speaker 2: the planets were made, but it was never able to
• 15:06
  Speaker 2: form a planet because it's giant right next to it,
• 15:09
  Speaker 2: as gravity is kind of swishing.
• 15:10
  Speaker 4: It around a lot.
• 15:12
  Speaker 2: So yes, logical reasons why we understand these different sorts
• 15:16
  Speaker 2: of belts.
• 15:17
  Speaker 1: What about the oat cloud? Yeah, would that be an
• 15:22
  Speaker 1: asteroid belt of some kind?
• 15:24
  Speaker 2: I'm meant to mention the oak cloud. Thank you for
• 15:26
  Speaker 2: reminding me, Andrew, that's more of a sphere of objects
• 15:31
  Speaker 2: rather than the belt of objects. I mean, we think
• 15:33
  Speaker 2: of a belt as being within the plane of the
• 15:34
  Speaker 2: Solar System, as indeed the asteroid belt is. The Transceptunian
• 15:40
  Speaker 2: objects are much more highly inclined in their own bits,
• 15:42
  Speaker 2: so they're not really a belt, but they're more like
• 15:44
  Speaker 2: a belt than the Oak cloud, which is thought to
• 15:47
  Speaker 2: be something that surrounds the Solar system completely. And yes,
• 15:52
  Speaker 2: again it's the outer edges of this blob of gas
• 15:55
  Speaker 2: and dust from which the Solar System formed. So the
• 15:59
  Speaker 2: oak cloud is where the bits come from, and they
• 16:01
  Speaker 2: are mostly made of vice. So that's a big difference.
• 16:06
  Speaker 1: Yeah, all right, So the answer to say Andy's question
• 16:08
  Speaker 1: is yes.
• 16:09
  Speaker 2: Ish, it's yes, and it's big time yes really because
• 16:14
  Speaker 2: we've got you know, so much more that we now
• 16:17
  Speaker 2: know about the Solar System, and it's various families of
• 16:20
  Speaker 2: minor objects, small objects which are important to us because
• 16:24
  Speaker 2: these things occasionally collide with the Earth, so that's why
• 16:28
  Speaker 2: we need to know about them.
• 16:30
  Speaker 1: It would it be logical to suggest that these kinds
• 16:34
  Speaker 1: of belts exist in other solar systems.
• 16:37
  Speaker 2: Yeah, I think so. There's the problem with trying to
• 16:41
  Speaker 2: discover them is that the objects in them are so
• 16:43
  Speaker 2: small that they're you know, trying to detect them from
• 16:47
  Speaker 2: from the distance that we are, which is measured in
• 16:49
  Speaker 2: light years rather than millions of kilometers as we are
• 16:51
  Speaker 2: in the Solar system. That's a difficult task, but maybe
• 16:57
  Speaker 2: one day we'll find some evidence. There is actually evidence,
• 16:59
  Speaker 2: there's evidence of comic clouds. For example, around one star
• 17:05
  Speaker 2: from below if I remember rightly had an object that
• 17:12
  Speaker 2: was in its protoplanetary disc that's the disc of stuff
• 17:14
  Speaker 2: that's got a form planets that actually broke up into
• 17:18
  Speaker 2: into pieces, and it's thought to have been an asteroid collision.
• 17:21
  Speaker 2: And we've also seen a very peculiar star that has
• 17:25
  Speaker 2: a brightness range that changes, and the thinking is that
• 17:30
  Speaker 2: we're seeing a cloud of comments passing in front of it.
• 17:33
  Speaker 4: So yes, there evidence is there, right.
• 17:36
  Speaker 1: Okay, thank you Sandy, Great question, and yes you were right.
• 17:42
  Speaker 5: Okay, we take a.
• 17:45
  Speaker 1: Space neuts. Our final question today comes from Steve.
• 17:50
  Speaker 2: Hi.
• 17:51
  Speaker 5: Guys, it's Steve here from Liverpool and England. Actually just
• 17:56
  Speaker 5: across the river from Liverpool, so technically plastic sculpture. Just
• 18:01
  Speaker 5: a question reference. Do you ever think a Von Brawn
• 18:06
  Speaker 5: wheel or you know wheel space station will ever be built?
• 18:11
  Speaker 5: It's within our capabilities now, I think, you know, with
• 18:15
  Speaker 5: multiple launchers and modular design they could even sell different
• 18:20
  Speaker 5: modules to hotels, et cetera. But do you think it'll
• 18:24
  Speaker 5: ever be built? Thank you, take care and calling on
• 18:28
  Speaker 5: with the show.
• 18:28
  Speaker 1: Cheers, Good on your Steve. Thank you. I'll be visiting
• 18:32
  Speaker 1: Liverpool sometime next year. Can't wait.
• 18:35
  Speaker 4: Can't go to the Beatles experience and do its grown.
• 18:38
  Speaker 1: That's exactly what I'm going to do. Yeah, I'm going
• 18:41
  Speaker 1: to do the Beatles Tour. Yeah, space Wheel. The first
• 18:44
  Speaker 1: time I ever became aware of space Wheel, Fred was
• 18:47
  Speaker 1: when I was a kid and I used to watch
• 18:48
  Speaker 1: a TV show called Space Patrol. It was one of
• 18:51
  Speaker 1: those marrying it type shows. Yeah, they Captain Scarlett was
• 18:59
  Speaker 1: was probaly will be the most famous of the shows.
• 19:02
  Speaker 1: This one was called Space Patrol and one of the
• 19:04
  Speaker 1: space ships was actually a space wheel that I don't
• 19:09
  Speaker 1: remember much more about it than that. I do remember
• 19:13
  Speaker 1: a strange space creature called Gabbler, and they were trying
• 19:17
  Speaker 1: to teach him to say medicine, but he kept saying
• 19:20
  Speaker 1: pencil instead. Look, I don't know why that's stuck in
• 19:24
  Speaker 1: my head. Say pencil, Say medicine, Gabler. He'd say pencil.
• 19:29
  Speaker 1: Or was it say pencil, Gabler, He'd say medicine. It was.
• 19:32
  Speaker 1: It was a sweet, some weird interstellar bird. I've got
• 19:37
  Speaker 1: some strange memories from my childhood, but that one sticks
• 19:40
  Speaker 1: out because of the space wheel. Do you think we'll
• 19:44
  Speaker 1: ever build one?
• 19:46
  Speaker 2: I do, because it is, you know, the most direct
• 19:54
  Speaker 2: way of trying to provide well, that's the only way
• 19:57
  Speaker 2: we know of trying to provide an artificial gravity in
• 20:00
  Speaker 2: a spacecraft that's away from the Earth. You've got to
• 20:02
  Speaker 2: be very careful about it, though, because there are only
• 20:04
  Speaker 2: certain limits between which you can build it in terms
• 20:08
  Speaker 2: of diameter and how fast it rotates. What gives me
• 20:13
  Speaker 2: some confidence in this is a conversation I had. It's
• 20:15
  Speaker 2: quite a number of years ago now, but with the
• 20:19
  Speaker 2: husband of Linda Spilker, Linda Spilker was the mission scientist
• 20:22
  Speaker 2: for Cassini for the Cassini Space mission. Her husband Tom
• 20:26
  Speaker 2: is the space engineer contracted to NASA. He was at
• 20:30
  Speaker 2: the time, I guess it problem still is and his
• 20:32
  Speaker 2: specialty is space wheels. It's all designing the possibility of
• 20:38
  Speaker 2: these large rotating structures in space that will give you
• 20:42
  Speaker 2: artificial gravity. I know, when I think of the future
• 20:47
  Speaker 2: of humankind, I tend to think of them not as
• 20:52
  Speaker 2: colonizing Mars, which I think would be a bad thing
• 20:54
  Speaker 2: to do, but I think of them building megastructures in
• 20:57
  Speaker 2: space which might have artificial gravity, a bit like the
• 21:00
  Speaker 2: Halo world from that very well lit early game. Oh yeah,
• 21:05
  Speaker 2: it was in the early years of the century. Love
• 21:08
  Speaker 2: loved playing that game with the boys when they were
• 21:10
  Speaker 2: at home. And of course they made it into a
• 21:12
  Speaker 2: TV series, although they've got canned after two seasons, but yeah,
• 21:17
  Speaker 2: it's become a huge franchise. Did you know I might
• 21:20
  Speaker 2: have mentioned this before, but in Halo there was a
• 21:23
  Speaker 2: Private Chips.
• 21:23
  Speaker 1: Dubbo, one of the characters. Yeah, Private Chips Dubbo because
• 21:29
  Speaker 1: and he had an Australian accent.
• 21:31
  Speaker 4: And well there you go.
• 21:33
  Speaker 1: So he appeared in the first version of the Halo
• 21:36
  Speaker 1: video game, Private Chips Dubbo because I'm from Dubbo. This
• 21:39
  Speaker 1: is where I am. So yeah, so somebody must have. Yeah,
• 21:43
  Speaker 1: it's a great name. Love it. And he didn't get
• 21:46
  Speaker 1: killed off. He wasn't he wasn't a Red Shirt. Sorry
• 21:50
  Speaker 1: I'm getting I'm digressing. Space wheels, Yes, but you're right
• 21:54
  Speaker 1: that was the Halo was a space wheel, a big one.
• 21:57
  Speaker 4: Yeah.
• 21:58
  Speaker 2: And if we could lost to the engineering to build
• 22:00
  Speaker 2: something like that, I think that's a far better way
• 22:02
  Speaker 2: than colonizing a lot of the world that might have,
• 22:07
  Speaker 2: you know, rudimentary microscopic life on it.
• 22:10
  Speaker 1: So if you build a space wheel, and as you said,
• 22:14
  Speaker 1: you've got to be careful because of size and speeds
• 22:16
  Speaker 1: and creating that oneergy effect, would bigger be better because
• 22:21
  Speaker 1: you wouldn't have to rotate it nearly as fast or
• 22:24
  Speaker 1: I don't know.
• 22:24
  Speaker 2: Yeah, Yeah, it's a it's a fine line between the two.
• 22:28
  Speaker 2: It's I looked at some of the work that Tom
• 22:31
  Speaker 2: Spilker is done, and you know, you you've you've wanted
• 22:35
  Speaker 2: big enough that it mimics gravity rather than making you
• 22:40
  Speaker 2: feel sick, which is what happens with the smaller ones,
• 22:44
  Speaker 2: and you know you want you want to ensure that
• 22:47
  Speaker 2: if you if you drop something in this artificial gravity,
• 22:50
  Speaker 2: it just goes directly downwards rather than moving sideways, which
• 22:53
  Speaker 2: if it's too small and rotating too quickly, then it
• 22:56
  Speaker 2: would do or moving.
• 22:59
  Speaker 1: I'm just thinking all these questions as I go. But
• 23:01
  Speaker 1: if you did build a space wheel in orbit around
• 23:04
  Speaker 1: Earth as a hotel or whatever, a research center, probably
• 23:09
  Speaker 1: both in years to come, and who knows what else,
• 23:11
  Speaker 1: But would you have it pointing at Earth on its
• 23:14
  Speaker 1: axis or on its wheel? Because if you if you
• 23:18
  Speaker 1: had it sort of wheel up, then you'd be standing
• 23:24
  Speaker 1: with your feet in proximity to Earth. But if you
• 23:26
  Speaker 1: put it on its axis, you'd actually be standing sideways.
• 23:31
  Speaker 4: Yes, I think what you might do both, couldn't it?
• 23:35
  Speaker 2: Yeah?
• 23:35
  Speaker 4: You could? I think you'd.
• 23:39
  Speaker 2: You you you know, I'm guessing here that what you'd
• 23:44
  Speaker 2: want to do is really aligned it up in terms
• 23:47
  Speaker 2: of where the Sun is. So if you had it
• 23:52
  Speaker 2: with its axis pointing towards the Earth, but in a
• 23:54
  Speaker 2: geostatiary orbit, so it was going around the Earth once
• 23:58
  Speaker 2: a day, that would mean that you'd sort of limit
• 24:02
  Speaker 2: the twenty four hour cycle of night and day.
• 24:08
  Speaker 4: In a way that you wouldn't if it was some
• 24:10
  Speaker 4: other way.
• 24:11
  Speaker 1: That's a good thought. Yeah, actually that's a really good thought. Yeah,
• 24:15
  Speaker 1: I know, trust you to come up with a better
• 24:19
  Speaker 1: idea than me. Yeah, I'm glad did that makes perfect sense?
• 24:23
  Speaker 1: So the answer is yes, probably it will happen. Why
• 24:28
  Speaker 1: hasn't it happened yet? I think they've been focused on
• 24:30
  Speaker 1: other things for it.
• 24:31
  Speaker 2: I suppose it's fairly significant engineering. You know, there was
• 24:38
  Speaker 2: certainly talk of earlier in the idea of sending people
• 24:42
  Speaker 2: to Mars, probably a couple of decades ago, of making
• 24:45
  Speaker 2: two spacecraft that are tied together and rotate about their
• 24:49
  Speaker 2: common center of gravity and that basically provides artificial gravity.
• 24:54
  Speaker 2: But even that turned out to be just a little
• 24:58
  Speaker 2: bit beyond the engineering we've got at the book.
• 25:01
  Speaker 1: Although we sound like we're going to get there. Thanks Steve,
• 25:05
  Speaker 1: I hope you will, hope all as well in Liverpool,
• 25:09
  Speaker 1: and thanks for your questions. We've got a whole bunch
• 25:12
  Speaker 1: of new questions that have come in that we're going
• 25:14
  Speaker 1: to get through. That doesn't mean you should not send
• 25:16
  Speaker 1: them to us, So go to our website, Spacenuts podcast
• 25:19
  Speaker 1: dot com or spacenuts dot io and have a look
• 25:24
  Speaker 1: around while you're there. But if you've got a device
• 25:26
  Speaker 1: with a microphone like a smartphone or a computer or whatever,
• 25:33
  Speaker 1: you could send us audio questions. Just don't forget to
• 25:36
  Speaker 1: tell us who you are and where you're from. Or
• 25:37
  Speaker 1: you can send us text questions via the AMA link
• 25:40
  Speaker 1: on our homepage. And that's about it, Fred, thanks so
• 25:45
  Speaker 1: much for answering all those questions for us today.
• 25:48
  Speaker 4: It's a pleasure.
• 25:49
  Speaker 2: It's what I do, so I'm likely to do that
• 25:53
  Speaker 2: all right, and we'll up with you again real soon.
• 25:57
  Speaker 1: Fred, what's an astronomer at large? And here in the
• 25:59
  Speaker 1: student video who I think was taking the bins out
• 26:03
  Speaker 1: when we started this episode and we I've got to
• 26:06
  Speaker 1: do that.
• 26:09
  Speaker 4: Thank you, interesting to do it tomorrow.
• 26:11
  Speaker 1: Uh, And from me Andrew Acpley, thanks for your company
• 26:13
  Speaker 1: catching on the next episode of space Nuts. Until then,
• 26:16
  Speaker 1: bye byepaceus.
• 26:18
  Speaker 4: You'll be listening to the Space Nuts.
• 26:20
  Speaker 3: Podcast available at Apple Podcasts, Spotify, iHeartRadio, or your favorite
• 26:28
  Speaker 3: podcast player. You can also stream on demand at bides
• 26:31
  Speaker 3: dot com.
• 26:32
  Speaker 5: This has been another quality podcast production from sites dot com.