Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #421: Zebrafish & Cosmic Cold Spots: Swimming Through Space Mysteries

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#421: Zebrafish & Cosmic Cold Spots: Swimming Through Space Mysteries · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
Hi there, Thanks for joining us. This is Space Nuts where we talk
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astronomy and space science and sometimes recipes and wallpaper design. Coming up on this
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episode, we're going to be talking about zebra fish in space. Yep,
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they're up there, they're orbiting, they're making crucial decisions, and we're going
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to find out why. We're also going to look at the cold spot in
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space. It's part of the cosmic microwave background radiation. But why is it
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there and what's it doing? That is the sixty four thousand dollars question.
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And we'll talk about a few other things as well. Coming up on this
0:37
episode of Space Nuts fifteen second guidances in Channal ten nine ignition sequence Space Nuts
0:47
side or three two one Space Nuts as when I report it Mel Goods And
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once again we're joined by Professor Fred Watson, Astronomer at Large. Hello,
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Hello Andrew, How are you this morning? How are you today? I'm
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cold, I'm cold. The weather's really starting to chill down in my part
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of the world, which is not my favorite time of the year. But
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it's not even winter yet, but we've just hit a bit of a cold
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patch. We must be in the middle of the cosmic microwave microwave background radiation
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because it's it's something kelvin here at the moment. I think you hit one
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degree last night, didn't you. I saw it's on the something like that.
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Yeah. Yeah, it's a lot of people think that the West is
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just a hot dust pan, but in winter it is definitely not. That.
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We get some very cold nights here. But you know, people in
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North America are probably going, oh, oh, yeah, you don't know
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what cold is. No, I don't. I don't want to find out.
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That's all good and well, Fred, Before we get into your topics,
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I just wanted to bring something up because we've talked about this before,
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and there's been an announcement made this week that the thirty two hundred megapixel Legacy
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Survey of Space and Time camera that was being built for the Verra sa Uben
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Telescope has been delivered. I finished making it in April and it's been flown
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by seven four to seven cargo plane to its location and it's now been delivered
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to the telescope. So they're really getting to the pointy end of this project.
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What intrigues me about this is that it's the biggest digital camera that's ever
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been produced, thirty two hundred megapixels, and it is super duper sensitive,
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and it will be able to take a very wide field view. I think
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its observing power is seven times that of the width of a full moon,
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which is amazing. So a four months half a degree across, So what
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that's telling you is three and a half degrees field of view, which is
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extraordinary for a telescope that size. It's an eight point four meter telescope which
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is going to survey the whole sky I think every five nights or three nights
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or something ridiculous like that, looking for things that change. It's transient astronomy,
3:35
as it's called. And yeah, I think I read the term time
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lapse. They're going to do a ten year time lapse of the southern sky.
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Yeah, that's right. What you could learn from that might be just
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amazing because we just see the sky in real time and it's so easy to
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miss things, I would imagine. Yeah, so principally what they'll be looking
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at is things that move, and that means it's going to net thousands and
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thousands of asteroids, possibly the more distant ones it'll probably discover, you know,
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coyper melt objects may even find planet nine. Actually, it's probably one
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of the best potential tools for finding planet nine, if Planet nine exists.
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But also things that change in brightness, exploding stars, anything that kind of
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goes bump in the night, it'll pick up because of that cadence of you
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know, observing the Hull sky every few nights. It's a remarkable machine.
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I was looking at a picture. Another announcement that you might have missed that
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came from it about three weeks ago was that they've just put the coating on
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the main mirror. The main mirror, as I said, eight point four
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me in diameter, but it's a very unusual mirror because it's dished like all
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telescope mirrors are. But there's a section in the middle which is sort of
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probably more than half the diameter of the mirror, which has a different curvature,
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so it's like a double dish. Is really quite extraordinary to look at.
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If anybody feels like googling that, look for surface coating of ver a
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c rubin telescope mirror or something like that, and you'll see a marvelous picture
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of this strange double dish mirror. And it's like that because the light from
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the stars hits the outer part of the mirror, is reflected back then to
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a second mirror, and then hits the main mirror again but in a different
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part, so the different curvature focuses it in a different way. It's a
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very intriguing design of instrument, quite different from the Northern Yeah, I knew
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you'd know all about it, because I know you're just sew into telescopes.
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You've written a book about telescopes and there they all came about you did,
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yes, And I just when I spotted that story, I thought I'll just
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have to bring that up with for it because you'll probably know the guff on
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it. But yeah, well, with the camera now being delivered, they're
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getting really close to commissioning this, this telescope. My only thought is like,
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it's going to be a ground based telescope, but I'm guessing that this
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is going to be such an altitude that atmosphere is not going to be as
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big a factor as it is in other parts of It's a good site,
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that's right. It's in It's not that far from Lace Arena in Chile.
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I've seen it actually from across the other side of the Valley. Haven't visited
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the site, but I've seen it and it shares that the dog. It
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shares that to sorry everybody. It shares the site with the Germany South Telescope
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as well, which is another eight meter telescope, but one that doesn't have
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that same field of view. So yes, an extraordinary instruments have been been
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a long time in gestation, has that telescope. We've been talking about it
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for many, many years, but it's now very near to fruition and Australian
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astronomers have got a bit of a tour in the door because we've got to
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deal with the observatory that allows us to analyze the data and look at some
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of the stuff that's coming off it. So there might be Australian covery is
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made from that telescope as well. One we can only hope so, and
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we will certainly be keeping an eye on this and we'll talk about it when
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it gets up and running, whenever that will be in astronomical terms, could
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be another twenty five years now, it won't be that long, but twenty
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five million years sometimes maybe maybe From the world's biggest camera to some of the
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world's smallest astronauts we're talking zebra fish in space or aquaauts. Maybe they are,
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but these are zebra fish that are on a Chinese mission. What's this
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all about, Fred, And how did they make the helmets so small?
7:41
It's about research. This is research taking place on Tiangong, a space station,
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the Chinese space station. Tiangong, of course, means Heavenly Palace,
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is a lovely name for what is quite an able and certainly pretty efficient and
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effective piece of kit. It's about a third the size of the International Space
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Station, so no when he was big, but more modern in many ways.
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But they've got five hundred people in there. I won't touch that one
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either. I think the standard crew is three. I think that is correct.
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But of course there are experiments going on on that space craft, just
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as there are on the International Space Station, and one of them is to
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look at the effects of space on fish, and in particularly zebra fish.
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Four of them, I'm sure they've all got names, which are apparently doing
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really well. And they except they don't know which way up to swim,
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as as you can't kind of expect because you know the fielding the gravity,
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so that they're swimming upside down. Things of that sort but anothers this is
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being take is being done. One thing I didn't know is that they zebra
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fish apparently have genetic similarity to humans. I'm gobsmacked by yes. I mean,
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that doesn't surprise me that we're, you know, only a couple of
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degrees away from a mountain gorilla. But do you have a an anatomical similarity
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to the zebra fishes? Yeah, I don't know that's quite anatomical, but
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it is certainly when you look at the gene you know, the genetic makeup
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there there are in common. And that's that's that's why they've chosen zebra fish,
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because it's a it's a model for you know, perhaps seeing what the
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effects of space are on the zebra fish that might correlate with some of the
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things that we know happened to humans and maybe lead to treatments and things of
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that sort that we could use here on Earth. So yes, very very
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interesting. They're calling them, I'm just going to say they're calling them a
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quster a questronauts, because I can't say it because they were a classic I
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guess, go for it. Yeah, I used to keep zebra fish when
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I had fish in my house. I used to love keeping fish. I
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had several aquariums over the years. Interest and zebra fish were great. They
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were a schooling fish, so if you got enough of them, it just
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looked really good in the fish tank with all these fish sort of swimming around
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seemingly aimlessly, but they all clustered together. I cleaned the tank out once
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and I was just about to dump the rubbish and I saw something moving in
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the bottom of the bucket and I picked I actually captured it with a straw.
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I put the straw over it, and then somehow managed to create a
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suction effects by squeezing the straw and caught this thing and put it in the
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jar. Didn't know what it was, but it was. It was about
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the size of an eyelash. Oh wow. And it grew into strawberry ze
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fish yep, yep. So it makes me wonder how many I sucked down
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the toilet. But anyway, but yeah, he grew into a he or
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she grew into a reasonable size until another fish went, oh, I mean
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lunch. I'm pretty sure that's what happened to him, because he disappeared.
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Yeah, but it was pretty exciting. But they are prolific breeders and that's
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one of the things they're going to be looking at, is the effect of
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zero gravity on their eggs and everything else. Pretty it's really interesting stuff,
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it is. But we've had so many different creatures in space, spiders,
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and they've had ants. They've done ant colonies in space, because we've had
11:52
dogs in space and a few other things. This is not the first fish
11:56
in space. I didn't think that goes back to nineteen seventy three. In
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fact, when Skylab hard experiments on board which used fish, I would call
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them gudgeons, but I think they've got different names in different parts of the
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world. D skippers, Yeah, that's right, and they Yeah, so
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that was quite successful as well. I think there's been other experiments. I
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think actually on the Apollo Soyots missions there were fish as well. So it's
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I mean, you kind of wonder whether they ever end up with chips on
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a plate or something like that, but probably not. I was going to
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say that the first fish in space was a beautiful salmon steak, but maybe
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I don't know if that's I don't know if that's true. You mentioned gadgets.
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There's a specific gadget from our part of the world that's en dangered,
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and I remember they were doing a lot of work to try and restore its
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numbers in the Murray Darling base and it was the purple spotted gud I think
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quite striking. Actually, when you get up close to them, they've got
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these bright purple spots on them. They're amazing fit. It's a it's a
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strange fish because it lives in and out of the water, and it sort
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of it's one of those things that sort of is sort of halfway between a
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sea creature and a land creature, or a quatic creature and a land creature
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in the evolutionary scale. It's quite quite amazing. So it doesn't surprise me
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they've had those in space. But zebra fish, Yeah, that kind of
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came out and left the field. But it sounds like their DNA makeup is
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a good reason to have them there because we can learn a lot about what
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happens to them and thus maybe what happens to us. I don't know.
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It's all part of a process, isn't it for it? Indeed, that's
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right. Yeah, So we'll follow that progress with interest. If there's any
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news about the zebra fish down the train, it will come to you.
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Via space Notes. Oh and yeah, one thing that I also want to
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that I read about that story is that they're trying to make these aquariums in
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space self sustaining. Yes, that's right. Yeah, I think that's another
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experiment they want to see if they can just sort of be in that environment
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and you don't have to do anything with them, they'll look after themselves long
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term, which is another thing we'll have to do as human beings if we're
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going to do long term space. Although I didn't know that they've come to
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replace the food box on the on the aquarium tak. Yeah. The only
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problem with this theory is that humans can't hold their breath live long. So
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yeah, well that's right. I mean you've touched on something that I just
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want to write about about. You've really got to meet your anything that's going
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to involve long time, long term visits to space to be self sustaining.
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All right. If you would like to chase up that story about zebra fish,
15:05
you can check out the Space daily dot com website. This is space
15:11
Nuts Andrew Dunkley here with Professor Frett Watson. Okay, we checked all space
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nuts. Our next story, Fred is a bit of a mystery. There's
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a cold spot in space and it's got something to do with cosmic microwave microwave
15:33
background radiation. And the reason I say is a mystery is because they're not
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sure why it exists. Is that where we're going with this, Yes,
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that's it in a nutshell, Andrew, So let's just revisit the cosmic microwave
15:48
background radiation, that microwave hiss that is all over the sky, it's over
15:54
the entire sky, discovered by Panzeas and Wilson Bucking the nineteen sixties and because
16:03
they realized it was realized that what we were seeing was a big bang,
16:07
the flash of the Big bang, that a look back time of thirteen point
16:11
eight billion years. As we now know, it's been a very important asset.
16:15
And the thing about the cosmic microwave background radiation, and this was predicted
16:19
back in the early days when it was just discovered as a kind of hiss
16:25
in microwave telescopes. It's got temperature variations in it, it's got slight changes
16:30
in intensity as you look at it. So there's a sort of pattern there.
16:34
And that also was predicted because without that pattern of hot, warm,
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and cold spots we wouldn't exist, the galaxies wouldn't have formed, there would
16:44
not be structured in the universe, and so that was a big discovery made.
16:48
It was Jeffrey Burbage who suggested that I might be get fingering the wrong
16:56
astronomer, but it was certainly a discovery made back in the time before we'd
17:00
even got the wherewithal to measure that that unevenness. The technical term for the
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unevenness of the cosmic microwave background radiation is an isotropy. When something is isotropic,
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it is the same in all directions. When it's an isotropic, it's
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not, and that's what the cosmic microwave background radiation is. So measurements of
17:22
the anisotropy of the cosmic microwave background radiation have been carried out by three major
17:27
space missions. Kobe back in the day nineteen nineties Cosmic Background Explorer that produced
17:34
the first maps, and then we realized that we could learn much much more
17:38
if we had a finer resolution, you know, rather than looking just at
17:42
big blobs on the sky, could you break them down into finer detail.
17:47
So w MAP was launched around about the turn of the century. I think
17:52
if I remember rightly, w map was the Wilkinson Microwave anisotropy probe, and
17:57
then finally the Plank spacecraft p L N p L A n c K,
18:03
which was sent into orbit by the Europeans, and that's given us the finest
18:07
detail of finest detailed maps of the cosmic microwave background radiation. All of that
18:15
has pointed though two cold spots, and in particular one cold spot that's bigger
18:21
than the rest and actually colder than the So it's quite extraordinary how small the
18:30
variations in temperature are. They're you know, in the region of ten to
18:33
the minus five of a degree, and so the basically the you know,
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you're you're looking at very very fine details. It's you know, one part
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per million is really the kind of level at which there is there is variation.
18:53
And I should say that the average temperature of that cosmic microwave background radiation
18:59
is to I think it's two point seven degrees kelvin roughly roughly three degrees kelvin,
19:04
so minus two hundred and seventy degrees celsius, very near absolute zero.
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So that is the backstory. What we're talking about now though, is and
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this was discovered probably quite early on in the history of our mapping of the
19:25
cosmic microwave background radiation, nearly thirty years ago. It's a spot that is
19:32
bigger and colder than the average. And so there's a few statistics that given
19:40
by a very nice article about this on space dot com, which our listeners
19:44
might want to have a look at. If you think about the average cold
19:51
spot on the cosmic microwave background radiation, it's about eighteen microkelvin's colder than average.
19:57
A microkelvin is a millionth of a degree calvin, which is effectively the
20:03
same as a degree celsius in that in that scale, So eighteen micro degrees
20:10
colder. But this one is kind of getting on for ten times that it's
20:15
one hundred and forty Wait a minute, no, it's much more. It's
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much much more. I've misread that because it's millie Calvin's one hundred and forty
20:25
million calvit's colder than average. Yeah, so that's you know, nearly ten
20:30
thousand times colder than the cold spots, the average cold spot. And it's
20:37
also, as I said, it's big, it's five degrees. We've just
20:42
had a conversation about the field of view of the of the V. C.
20:48
Rubin telescope, which is smaller than that. It's but it's a big
20:52
field of view. It's three and a half degrees, but five degrees is
20:55
a colossal size on the sky. So it's called and it's big. And
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that's very very interesting in you know, what is telling us you kind of
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expect to occasionally there'll be outliers of you know, any distribution of things based
21:18
on their size or the temperature or whatever. You're going to have outliers which
21:23
will be much more distinct from the general levels. However, the chances of
21:36
this being random are apparently less than one percent, and maybe maybe even lower.
21:41
And so there is thought as to the fact that there's a reason for
21:45
this. And excuse me, there is a kind of explanation which is a
21:55
bit complicated. I might read, Actually, if space dot Com will forgive
22:00
me, I will credit this to them and read the article. Who's the
22:03
author. It's Paul Suitor, who's very very able writer on this kind of
22:11
science. Let me just quote from Paul's article. So he says, the
22:18
favored exploration explanation for this strange cold spot is that it's due to a giant
22:23
cosmic void sitting between us and the court and the cosmic microwave background radiation in
22:29
that direction. Cosmic voids a big patches of almost nothing, and we know
22:33
they exist. I'm just an aside from me. We see that kind of
22:37
structure in the wider universe, what we call the cosmic web is a network
22:41
honeycomb of galaxies with not much in the spaces between them, a kind of
22:47
honeycomb space. And so that is perhaps one theory. And what then imprints
23:00
that a signal from that void on to the cosmic microwave background radiation. As
23:07
pointed out by Paul in his article, they influence the cosmic microwave background light.
23:15
And that's because those voids are evolving. It's changing because the universe is
23:22
a movable feast. The universe has motion. Everything's moving in the universe,
23:27
and so these voids are changing. So I'm qutting Paul here. There's a
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very really good paragraph that explains this very nicely. When light from the CNB
23:37
first enters avoid it gains a little energy as it transitions from a high density
23:41
to a low density environment. In a perfectly static universe, the light would
23:47
lose an equivalent amount of energy when it exited the other side. But because
23:52
the voids are changing, when the light first enters the void might be relatively
23:56
small and shallow, and by the time it leaves the void is big and
24:00
deep. This leads to an overall loss of energy the energy of the cosmic
24:06
microwave background like crossing the void, a process known as the integrated saxe Wolf
24:11
effect of saxe wolfa is probably how you should pronounce it, but we call
24:15
it saxe wolf so check that out online. The integrated sax Wolf effect is
24:19
this loss of energy in an evolving system. So, uh, there's there's
24:27
one final mystery here. Sorry, this is a long, complicated story,
24:33
that's exactly. But we we don't see avoid there because you know, we've
24:41
got these galaxy surveys which I've been involved with on the Anglo Australian Telescope and
24:48
other and the UK Schmidt Telescope. These are surveys that show us where the
24:53
galaxy galaxies are distributed and give you a map of in three dimensions of what
25:00
those the structure of the universe is like as as marked out by galaxies.
25:04
And yes there are voids there. This onny Come effect I was talking about
25:10
so the direction of this cold spot doesn't have an obvious void some and so
25:21
you know, some researchers are saying, well, yes, our surveys are
25:22
not complete, and that's certainly true. In completeness is one of the big
25:29
banes of any studies that are based on these galaxy surveys. But there there
25:36
are, you know, this research. Some researchers have said, well,
25:38
we think we've seen a void or a super void as it might be called.
25:42
So, yes, like brought hes void. Yes, that's right.
25:49
Yeah, So so that this is one of the mysteries that we're going to
25:56
have to leave as a mystery, I think, because nobody really knows what's
26:00
happening, and maybe this is what we're what we're Yeah, what we're saying
26:06
here is that cold spots in the cosmic microwave background radiation are not unusual,
26:11
but this is a bigger and much colder spot and it doesn't appear to be
26:17
associated with a void like all the others, all most of it. That's
26:21
correct, Yes, that's right. So there's something spooky about it, but
26:23
we don't know what it is. It's that's bigger and weirder than you could
26:30
imagine. And that's how they describe it in the article bigger, weirdly,
26:33
bigger, and weirdly cold. It's right, which is scientific speech. It
26:40
is, Well, that's when it's weirdly. You know, you're really on
26:42
the edge of knowledge that Yeah, I suppose. Obviously the goal is to
26:48
solve this, So I wonder what we learn if we do solve it.
26:52
There'd be something to learn, sure they would, Yeah, that's right,
26:56
they would. Indeed. It just challenge, though, the notion that the
27:00
universe is the same in all directions, which is a kind of fundamental tenet
27:06
of cosmology. I mean, we know there are galaxies and classes of galaxies
27:11
and things like that in various different directions, but when you average it over
27:15
the whole universe, effectively, it's the same in all directions. That's the
27:18
isotropic that I was talking about. That's what we we assume is the case.
27:23
And so most cosmological theories of the origin of the universe are based on
27:27
that idea. And if that's wrong, then yeah, I've got to look
27:32
at it. Yeah, I've got a rudimentary idea in my head which is
27:36
probably way wrong. But when I was a kid, I used to go
27:38
and swim in the reservoir up behind our house, and you'd swim through warm
27:42
patches and then you'd hear a cold patch. It's that what the universe is
27:48
like. Yeah, maybe I do remember that when I used to swim back
27:51
in the day as well, and it would be all to do with just
27:55
that, just the thermodynamics of what was going on in the pool where the
27:57
one bit was in the shade of trees and or you know what was deeper
28:02
and the water rotating through cycles of But that's true. You're very notice it,
28:11
even probably only a degree or so you'd notice. You think, oh
28:14
gosh, that's a cool bit there. Yeah, yeah, yeah, Well
28:18
we used to notice it because it would be beautiful and warm and then you
28:22
just swim. It's like swimming through some kind of membrane and suddenly it's freezing
28:26
cold. It is very strange, very strange, all right. As Fred
28:30
said, if you'd like to find out more about that that strange cold spot
28:37
in the cosmic microwave background radiation, it's space dot com and yeah, great
28:42
website and brilliantly written articles they publish as well. Fred. That's brought us
28:49
to the end. I just remind people If you're a YouTube follower, don't
28:52
forget to subscribe below, and don't forget about our website if you'd like to
28:57
visit us and check out what we've gotten offer there Space Nuts podcast dot com
29:06
com or space Nuts dot io. You can subscribe to the Astronomy Daily newsletter.
29:11
Don't forget about our Astronomy Daily podcast as well with Steve my brother one
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of the hosts, and plenty more on our website Space Nuts podcast dot com.
29:22
Thanks Fred, will catch you again real soon, hope. So I'm
29:26
looking forward to the next time. There's so much going on in the world
29:29
of space there is. Indeed, you never stop learning or wondering or wondering
29:34
what you can learn. Thanks Fred, Let's see you so, Fred Watson,
29:40
Astronomer at Large. And thanks to here in the studio who's having breakfast
29:45
at the moment and can't talk, and from me Andrew Dunpy, thanks for
29:48
your company. Catch you on the very next episode of Space Nuts. Bye
29:52
bye. You'll be listening to the Space Nuts podcast available at Apple, podcas,
30:00
Spotify, iHeartRadio, or your favorite podcast player. You can also stream
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on demand at bites dot com. This has been another quality podcast production from
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fights, dot com