The Pink, Salty Exoplanet — Could Humanity Travel to the Galaxy’s Most Colorful World?

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Andrew Dunkley: Hi there. Thanks for joining us yet again for

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another episode of Space Nuts where we talk

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astronomy and space science. My name is

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Andrew Dunkley. Hope you're well. Thanks for

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your company. Today we're going to try and

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understand the Martian

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moon of Phobos. Um,

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was it born of a collision like our moon, or

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was it captured? And what's going on

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inside might be the only way to find out what

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it really is. Uh, we're also going to look at

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an exoplanet that my wife would adore. My

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wife loves salt. Like, you know, you give her

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a glass of ocean water and she says, can you

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put salt in that, please? Uh, this, this

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is, I'm not joking. This is

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an extraordinary planet and we'll tell you

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why. And uh, a very swift

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mission to save a vital space observatory.

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That'll make sense when we explain it all on

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this episode of, ah, space nuts.

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Andrew Dunkley: 15 seconds. Guidance is internal.

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10, 9. Ignition

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sequence start.

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Professor Fred Watson: Space nuts.

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Andrew Dunkley: 5, 4, 3, 2, 1. 2,

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5, 5, 4, 3, 2,.

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Andrew Dunkley: Space nuts.

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Andrew Dunkley: Astronauts report it feels good.

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Andrew Dunkley: And with us once more is Professor

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Fred Watson Watson, astronomer at large.

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Hello Fred Watson.

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Professor Fred Watson: Hello, Andrew. Hello. Nice to see you again.

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Yes, you too.

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Andrew Dunkley: We could do the whole show just

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Professor Fred Watson: talking rubbish like that.

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Andrew Dunkley: Well, we do that anyway.

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Professor Fred Watson: Uh, yes, I've forgotten that.

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Andrew Dunkley: Indeed.

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Andrew Dunkley: We got some really interesting storeys.

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Um, I mean Mars always fascinate

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me but uh, the moon Phobos in particular.

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Uh, and we've got a salty atmosphere in an

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exoplanet which um, I uh, haven't told my

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wife about because she'd probably want to go

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there and uh, um, a

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mission that's got to get off the ground

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ultra quick to save an

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observatory in space. I really, really

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am looking forward to that storey.

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But, um, let's uh, turn our attention to

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the Martian moon of Phobos.

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Uh, I did a little bit of research and it

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is apparent the um,

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closest orbiting moon of

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any planet in our solar system to its parent

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planet.

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Professor Fred Watson: That's not a surprise.

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Andrew Dunkley: Six thousand kilometres from the surface.

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Professor Fred Watson: Yeah, uh, in fact

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it's got this peculiar aspect

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uh, that uh, it

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orbits Mars. Of course, being a moon of

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Mars, it's the bigger of the two moons of

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Mars. It's only 23 kilometres across. So it's

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not really what you call a big moon. Uh, but

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it's got this extraordinary thing that it

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goes around Mars once in 7 hours and 39

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minutes. But Mars

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takes 24 hours and 40 minutes to rotate

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once on its axis. So this moon

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in Mars sky goes backwards.

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Um, its Own motion

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is enough to overcome the

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rotational motion of the

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planet. So, uh, yes, it goes

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more or less goes around twice a day. Uh, in

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fact, getting on for three times a day. Um,

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in fact, more than three times a day.

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My arithmetic's not very good at the moment.

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Um, so, yeah, uh, it's,

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uh, quite remarkable that you've got this

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phenomenon. So a, uh, very unusual

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moon. It's been known since, I think it was

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the 1880s. Um, uh, it

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was discovered, uh,

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actually by somebody who was related. There's

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a curious link. There's an uncle of

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Venetia Burney. Who you might remember was

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the young woman at the age of 11, I think,

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who gave Pluto its name.

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Andrew Dunkley: Oh, yeah.

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Professor Fred Watson: And she was in Oxford. And her uncle

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discovered, uh, the two moons of Mars. Very

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small objects, as I've said. Since that time,

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everybody's wondered how they got there. Uh,

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partly because they are small enough

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that it's

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possible they've got multiple different

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origins. Not simultaneously, but

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they've originated in, uh, a variety of ways.

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That's the possibility. Uh, so the two

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theories, um, one is. Well, more

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or less what you've alluded to already. One

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is that there was an event similar to the

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event that created our own moon. A collision

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in the early solar system by Mars

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with another, smaller object that sort of

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bashed into it, uh, lifted a whole lot of

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debris which coalesced to form the

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orbital. To form the object, uh,

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Phobos. And the other theory is that it's a

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captured asteroid. And I guess in the case of

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Mars, that's got some attractions to it.

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Because, uh, Mars, of

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course, is right on the inner edge of the

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main asteroid belt. So not very far from

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Mars. There are lots and lots of asteroids

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lurking. And we know from the way

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Jupiter's great gravitational pull Tinkers

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around with that asteroid belt, uh, that once

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in a while they stray from the main belt and

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you might get a capture. Um, it's

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also been known for a long time to have

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a peculiar composition. Its density

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is very low. And the suspicion is that it's

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made of something a bit like pumice. Um, you

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remember pumice being the

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material that, uh, is formed when

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volcanoes erupt underneath the ocean. You

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get this aerated stuff, almost like a

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foam. Um, and so its density

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is low enough that people don't really know

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whether that's what its interiors like.

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Uh, and of course, the other possibility,

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when you've got something with a low density

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like that, um, in common with many asteroids,

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is that it could be a rubber pile in

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other words something that's just made of

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loosely bound material all sort of stuck

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together by its own gravity, very feeble

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gravity because it's very small. Um, I have

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to say, um, Phobos doesn't look like that. It

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does look like a more solid object and it's

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got surface features including several quite

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big craters and one very big crater, uh,

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which is called Stickney. Um, I think

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it's about seven kilometres across and in an

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object that's only 22 and a half kilometres

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across. 22.2 actually. Um,

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that is a big crater.

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So all these factoids come together to make

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us wonder how it got there, what it's made

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of. Uh, and just one other comment about

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its orbit. Um, its orbit around

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Mars is not stable, uh, over a uh,

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long enough period of time and I think we're

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talking a few million years perhaps it

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will probably collide with Mars

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or just be pulled to pieces

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because it will get within the Roche limit of

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Mars. That's the, the limit within which a

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solid object can't exist or

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a solid object of any given size can't exist

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because of the gravitational disturbance.

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We've talked about Roche limits before I

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Andrew Dunkley: think and, and if it's, if it is pumice

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like. Yeah, there's every chance it will

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sort of crumble in the, in the sky.

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Professor Fred Watson: Yes, that's right. Uh, not, you know,

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not a uh, not a

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solid object that would resist uh,

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gravity. Tidal forces is technically what

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they are. Tidal forces are when one end of an

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object feel a different gravitational pull

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from the other end. Uh, and so um, yes,

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tidal forces would perhaps deal

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the final blow. Um,

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but yes, so studies looking

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at what uh, Phobos is

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made of and I guess these are coming out and

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the interest is growing in

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advance of um, an upcoming space

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mission which is being launched by the

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Japanese uh, Aerospace

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Exploration Agency jaxa. Uh,

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it is called the Martian Moons

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Exploration. Uh, it's uh,

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otherwise known as MMX and it is a

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Phobos sample return mission. So

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clearly this mission is expecting to land

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on the surface of Phobos. Uh, it will

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launch later this year and it will.

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What the pundits uh are saying is it will

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attempt a quasi stable orbit around the

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tiny moon. This is a difficult task because

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there is truly no stable orbit around Phobos

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and the reason for that is that you've got

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this thing with such weak gravity that

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getting something into orbit around it will

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be a challenge in the first place. But right

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next to it, 6,000 kilometres away, as you've

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said, is a large planet, um, not a

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large planet by planetary standards, but a

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large by the standards of Phobos.

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So lots uh, of challenges there and I think

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um, hopefully it'll be something we will

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cover uh, over the next couple of years or so

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to find out what is happening with

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Phobos.

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Andrew Dunkley: And I understand that to try and figure out

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how it became Phobos. Is

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everything to do with what's happening inside

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Phobos?

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Professor Fred Watson: That's right, yes. Um,

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there's one. So there's a

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suggestion that it may actually have

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a large ice content, um, as well

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as rock, uh, but we just don't

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know about that. There's also, I think uh,

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there is suggestion too that

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um, there's

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a higher density region

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underneath this crater. Ah, Stickney. And

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you can sort of imagine that would be the

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case if you've got something um, which

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is like a piece of pumice or a kind

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of sponge like structure, you get a large

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ish object clouting the surface, which is

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probably what caused Stickney. You're going

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to get some compression, what you might call

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a localised zone of densified

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material. As the authors of this paper,

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uh, which has appeared in the monthly notices

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of the Royal Astronomical Society.

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Andrew Dunkley: Yeah, well, when you look at the close up

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image that came from NASA jpl,

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uh, yeah, it doesn't look,

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I don't know how you'd describe it. Uh, I

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mean it's got a potato shape about it but

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it almost looks metallic in some respects.

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Professor Fred Watson: It does, that's correct. It's got. And

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I guess what you're looking at is kind of the

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same things that I see when I look at it. And

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that is craters with relatively sharp

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edges to them on the scale that we can

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see. And you know, that doesn't sound like

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something made of pumice. Um, if you've got

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uh, craters that have got well defined edges.

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So many mysteries, um, we came close

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to knowing more

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quite a few years ago. It's probably a decade

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ago now. Do you remember Phobos Grunt? Uh,

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yes. Which was a Russian

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spacecraft, uh, that was uh,

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going to go to Phobos and bring back a

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sample. Uh, Phobos Grunt. Grunt

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is effectively the Russian word for ground

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or you know, landing on the surface.

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Um, and uh, it failed

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because it got into orbit. But the

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spacecraft that was going to push it in the

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transfer orbit to Mars didn't work.

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And so eventually it just re. Entered back

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into the Earth's atmosphere. It was very sad.

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Um, it was um, uh, you know, a

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mission which we, we expected

267
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great things from.

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Andrew Dunkley: So maybe, um, the engines didn't fire

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properly.

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Professor Fred Watson: I think that was right. Yes. Yeah, that's

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right.

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Andrew Dunkley: And, uh, it. It just got stuck in low Earth

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orbit and that was the end of that.

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Professor Fred Watson: Yep.

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Andrew Dunkley: Yeah, it happens. It happens.

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Professor Fred Watson: It does. We hope it won't happen with mmx,

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the, The Japanese mission.

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Andrew Dunkley: No, no. Um, I. Yeah, well,

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you can never say never, but, um, hopefully

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it will be very successful and we will learn

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more about Phobos and what makes it tick.

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Which way do you lean? Solid object that got

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captured or a collision

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type of event?

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Professor Fred Watson: I didn't know it ticked. Anyway, never mind.

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Andrew Dunkley: I hope not.

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Professor Fred Watson: I do too. Um, I think

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it might be a captured asteroid. That will be

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my view. Um, it's

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got sort of characteristics of asteroids

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that. That makes me think maybe

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it is basically just something that

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wandered too close to Mars and got captured.

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Andrew Dunkley: Yeah, I'm leaning that way too, but only

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because it seems more logical. I have no

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scientific backup to my claim, but, um,

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anyway, neither do I, really.

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It's, ah, interesting, Storey. You can read

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about it in the monthly Notices of the Royal,

300
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uh, Astronomical Society, as Fred Watson

301
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said, or you can go to universetoday.com,

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this is space Nuts, the podcast about

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astronomy and space science.

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Space Nuts and Fred Watson.

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We're going a little bit further away than

306
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Mars. We're heading 50, uh, seven light

307
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years away to, uh, an exoplanet. Uh, it's

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called GJ 504B.

309
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Uh, this planet has got a couple of really

310
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amazing characteristics. Um, one

311
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being it is pink.

312
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And the second being its atmosphere

313
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seems to be very, very salty. In fact, it

314
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could be the Himalayan

315
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salt planet, you just never know.

316
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Himalayan pink salt, very, very popular.

317
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Um, it's a very strange one

318
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and my wife would love to go there because,

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uh, as I've said, she really adores salt. You

320
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give her a steak, put salt on it, give her,

321
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um, um, vegetables, put salt on it.

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Andrew Dunkley: It.

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Andrew Dunkley: Ice cream, put more salt on it. Yeah,

324
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she loves her salt. Um, now

325
00:14:09.620 --> 00:14:11.620
I'm going to suffer a salt and battery if I

326
00:14:11.620 --> 00:14:12.740
keep talking about it like that.

327
00:14:14.420 --> 00:14:16.780
Tell us about this unusual pink planet.

328
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Professor Fred Watson: Yeah, I'm glad you did the Himalayan

329
00:14:19.540 --> 00:14:22.500
salt thing, because if you hadn't,

330
00:14:22.500 --> 00:14:25.300
I would have done. Yeah, that's

331
00:14:25.300 --> 00:14:26.700
right. I don't know that the two are

332
00:14:26.700 --> 00:14:29.220
necessarily related. So, uh, it's, you know,

333
00:14:29.220 --> 00:14:31.380
there's quite a backstory with this. This is

334
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a planet, um, an exoplanet

335
00:14:35.190 --> 00:14:37.830
that is unusual in that we see it directly,

336
00:14:37.910 --> 00:14:40.310
as you and I have said many times.

337
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Uh most exoplanets we only infer their

338
00:14:43.270 --> 00:14:44.790
presence from the behaviour of their

339
00:14:45.910 --> 00:14:48.869
parent star. With this one we can

340
00:14:48.869 --> 00:14:50.430
actually see it which is how we know it's

341
00:14:50.430 --> 00:14:53.390
pink. Um, we've known about

342
00:14:53.390 --> 00:14:56.390
it for 13 years, discovered back in 2013.

343
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Uh but it's also a little

344
00:15:00.230 --> 00:15:03.060
bit um, of an enigma

345
00:15:03.700 --> 00:15:05.620
because its mass

346
00:15:06.420 --> 00:15:09.300
is about 25 times

347
00:15:09.300 --> 00:15:10.260
that of Jupiter.

348
00:15:10.740 --> 00:15:13.300
Andrew Dunkley: Yeah, uh, well salt's not light.

349
00:15:17.060 --> 00:15:19.500
Professor Fred Watson: Well notwithstanding the salt we might get

350
00:15:19.500 --> 00:15:20.980
back to that in a minute

351
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to some other salty tales. Um,

352
00:15:27.210 --> 00:15:29.370
the thing is that if this

353
00:15:30.090 --> 00:15:32.490
object were ah just on its own in space

354
00:15:32.890 --> 00:15:35.130
rather than in orbit around another

355
00:15:35.610 --> 00:15:38.490
world, we wouldn't call it a planet, we'd

356
00:15:38.490 --> 00:15:40.410
call it a brown dwarf star. Because

357
00:15:41.850 --> 00:15:44.730
the um, criterion for

358
00:15:45.130 --> 00:15:47.450
an object to be a brown dwarf star

359
00:15:48.170 --> 00:15:51.090
is a mass more than 13 times that of

360
00:15:51.090 --> 00:15:54.090
Jupiter because that's the mass

361
00:15:54.330 --> 00:15:56.970
at uh, which some low level nuclear

362
00:15:56.970 --> 00:15:59.730
reactions switch on that distinguish it, I

363
00:15:59.730 --> 00:16:02.290
think it's deuterium burning is the technical

364
00:16:02.290 --> 00:16:05.010
term, distinguish it as a star

365
00:16:05.250 --> 00:16:08.130
rather than a planet. Uh and so I think the

366
00:16:08.130 --> 00:16:09.530
only reason it's being called a planet is

367
00:16:09.530 --> 00:16:12.130
because it's going around uh, another star.

368
00:16:12.690 --> 00:16:15.330
You could in fact almost say it's actually

369
00:16:15.970 --> 00:16:18.970
a double star. Uh but people

370
00:16:18.970 --> 00:16:20.770
don't seem to be saying that. I think it's

371
00:16:20.770 --> 00:16:23.730
because that 13 Jupiter masses is

372
00:16:23.730 --> 00:16:26.370
a fairly blurry ah sort of

373
00:16:26.370 --> 00:16:29.180
boundary for an object to be

374
00:16:29.180 --> 00:16:32.100
classified as a brown dwarf.

375
00:16:32.660 --> 00:16:35.460
Anyway, um, brown dwarfs are

376
00:16:35.780 --> 00:16:38.780
well known, well studied. They are this sort

377
00:16:38.780 --> 00:16:41.580
of interim phase where you've got low level

378
00:16:41.580 --> 00:16:44.100
nuclear processes, you don't have the nuclear

379
00:16:44.100 --> 00:16:46.860
fusion that uh, characterises a

380
00:16:46.860 --> 00:16:48.530
genuine star. Um,

381
00:16:49.940 --> 00:16:50.950
so um,

382
00:16:53.300 --> 00:16:56.060
I've just noted a sentence in this

383
00:16:56.060 --> 00:16:58.220
very nice article about this from the science

384
00:16:58.220 --> 00:17:00.370
blog, um, which uh,

385
00:17:00.880 --> 00:17:03.000
puts it perfectly, it sums up just what I've

386
00:17:03.000 --> 00:17:05.330
said. Uh, it says uh,

387
00:17:05.680 --> 00:17:08.440
astronomers hedge their bets and call it a

388
00:17:08.440 --> 00:17:11.240
planetary mass companion and that

389
00:17:11.240 --> 00:17:13.400
gets over the problem. It's a planetary mass

390
00:17:13.400 --> 00:17:16.080
companion rather than a planet and

391
00:17:16.240 --> 00:17:18.880
not necessarily a star. So there you go,

392
00:17:20.720 --> 00:17:22.320
Andrew Dunkley: to quote Monty Pothon, you're just making

393
00:17:22.320 --> 00:17:22.800
that up.

394
00:17:26.080 --> 00:17:28.760
Professor Fred Watson: We make it all up and trim, you know that but

395
00:17:28.760 --> 00:17:30.520
they don't. You're right, they don't know

396
00:17:30.520 --> 00:17:33.510
that. So um,

397
00:17:34.880 --> 00:17:37.600
also interesting uh, because it's

398
00:17:37.600 --> 00:17:40.560
cool so you know the most of the,

399
00:17:40.560 --> 00:17:43.160
and I mean cool in a temperature sense rather

400
00:17:43.160 --> 00:17:45.840
than um, its presence on social media.

401
00:17:46.590 --> 00:17:48.960
Uh, uh, most of these

402
00:17:49.840 --> 00:17:52.640
objects like brown dwarf stars are well over

403
00:17:52.640 --> 00:17:55.560
a thousand degrees Celsius. Um, this

404
00:17:55.560 --> 00:17:58.540
one is only 290

405
00:17:58.540 --> 00:18:01.380
degrees Celsius. Uh and once

406
00:18:01.380 --> 00:18:03.070
again going back to that um,

407
00:18:04.780 --> 00:18:07.500
science blog article, they've said

408
00:18:07.500 --> 00:18:09.780
that's about the temperature of an oven

409
00:18:09.780 --> 00:18:12.700
baking bread, um, which

410
00:18:12.700 --> 00:18:15.220
is, um, worn by terrestrial standards, but

411
00:18:15.220 --> 00:18:18.180
not by space standards. And so we've got this

412
00:18:18.180 --> 00:18:21.060
object, which is a mystery, uh, but

413
00:18:21.060 --> 00:18:23.420
the reason it's in the news is because,

414
00:18:24.720 --> 00:18:27.610
uh, there have been studies

415
00:18:27.770 --> 00:18:30.250
with the James Webb Telescope. Apparently

416
00:18:30.410 --> 00:18:33.370
this object has been studied a great deal

417
00:18:34.250 --> 00:18:36.170
in the 13 years that we've known about it.

418
00:18:36.860 --> 00:18:39.850
Um, but it's some observations now made

419
00:18:39.850 --> 00:18:41.610
with the James Webb Space Telescope, which

420
00:18:41.610 --> 00:18:43.490
continues to amaze us because of its

421
00:18:43.490 --> 00:18:46.170
capabilities. Um, and the

422
00:18:46.170 --> 00:18:46.890
spectrum,

423
00:18:48.990 --> 00:18:50.730
uh, of its atmosphere,

424
00:18:51.950 --> 00:18:54.190
of course, reveals these different spectral

425
00:18:54.190 --> 00:18:56.350
fingerprints. We talk about that a lot and

426
00:18:56.590 --> 00:18:58.630
space nuts. And it's what I used to do for a

427
00:18:58.630 --> 00:19:01.230
living. Uh, the spectral fingerprints of

428
00:19:01.230 --> 00:19:04.200
stars and galaxies. Uh, anyway, um,

429
00:19:04.750 --> 00:19:07.509
observations with this revealed a

430
00:19:07.509 --> 00:19:09.550
spectrum that was very difficult to

431
00:19:09.550 --> 00:19:12.270
understand, uh, because it had

432
00:19:12.350 --> 00:19:14.670
features that didn't seem to make

433
00:19:14.990 --> 00:19:17.990
any sense. Uh, and

434
00:19:18.310 --> 00:19:20.630
it turns out that the trick was

435
00:19:21.430 --> 00:19:24.310
to look at different

436
00:19:24.310 --> 00:19:26.830
sorts of clouds that you might have in the

437
00:19:26.830 --> 00:19:28.870
atmosphere rather than just a clear

438
00:19:28.870 --> 00:19:31.510
atmosphere. And it was when they

439
00:19:31.830 --> 00:19:34.110
basically tried to fit the spectra that would

440
00:19:34.110 --> 00:19:36.960
be produced by different types of clouds, uh,

441
00:19:37.190 --> 00:19:38.750
to what they were observing with the Webb

442
00:19:38.750 --> 00:19:41.220
Telescope, uh, that these, uh,

443
00:19:41.220 --> 00:19:43.350
authors, uh, who've done this research

444
00:19:44.860 --> 00:19:46.860
found that the best fit was salt clouds.

445
00:19:47.900 --> 00:19:50.660
And now I find it hard to imagine whether

446
00:19:50.660 --> 00:19:53.040
those are clouds of salt, of pure salt, uh,

447
00:19:53.740 --> 00:19:56.700
in a solid form, um, or

448
00:19:56.700 --> 00:19:59.660
whether it's not salt vapour.

449
00:20:00.220 --> 00:20:01.980
I don't think, um, because at, uh,

450
00:20:02.060 --> 00:20:04.540
temperature, um, it's likely

451
00:20:04.860 --> 00:20:06.700
to be solid salt.

452
00:20:07.100 --> 00:20:09.320
Andrew Dunkley: Wow, that's. Wow.

453
00:20:10.350 --> 00:20:12.070
I'm gonna show this to my wife. She'll be

454
00:20:12.070 --> 00:20:12.910
very, very excited.

455
00:20:13.310 --> 00:20:15.790
Professor Fred Watson: It's drifting. It's drifting in the air.

456
00:20:16.440 --> 00:20:18.430
Andrew Dunkley: Uh, so I could go out there now and say, you

457
00:20:18.430 --> 00:20:19.950
know, with. They've found planets that are

458
00:20:19.950 --> 00:20:20.750
made of diamond.

459
00:20:20.910 --> 00:20:21.270
Professor Fred Watson: Yes.

460
00:20:21.270 --> 00:20:22.790
Andrew Dunkley: And they found one made of salt. She said

461
00:20:22.790 --> 00:20:23.470
we're going there.

462
00:20:23.550 --> 00:20:24.030
Professor Fred Watson: Yeah,

463
00:20:26.830 --> 00:20:27.950
yeah, there you go.

464
00:20:28.190 --> 00:20:30.510
Andrew Dunkley: I'm taking, I'm taking the mickey. But, yeah,

465
00:20:30.510 --> 00:20:33.190
anyway, uh, it, uh.

466
00:20:33.790 --> 00:20:36.030
I just thought of something which I probably

467
00:20:36.030 --> 00:20:37.470
should have said at the time, but it can't be

468
00:20:37.470 --> 00:20:39.110
a brown dwarf. It's got to be a planet.

469
00:20:39.260 --> 00:20:39.500
Andrew Dunkley: It.

470
00:20:39.580 --> 00:20:41.980
Andrew Dunkley: Because it's not the right colour.

471
00:20:43.420 --> 00:20:46.380
Professor Fred Watson: Yes. Being pink. It is not brown. Is. It

472
00:20:46.620 --> 00:20:47.460
could be a new.

473
00:20:47.460 --> 00:20:49.780
Andrew Dunkley: Could be. We could have discovered a pink

474
00:20:49.780 --> 00:20:50.220
dwarf.

475
00:20:50.780 --> 00:20:52.540
Professor Fred Watson: Yeah, well, maybe that's what it's going to

476
00:20:52.540 --> 00:20:54.740
be classified as. Because, you know, the, the

477
00:20:54.740 --> 00:20:57.420
colour itself must, must relate to,

478
00:20:57.740 --> 00:21:00.300
to what it looks like. To the, to the.

479
00:21:00.540 --> 00:21:03.260
Sorry, that's a tautology.

480
00:21:04.000 --> 00:21:06.340
Uh, the colour relates to the

481
00:21:06.340 --> 00:21:08.540
constituents of its clouds. That's what I

482
00:21:08.540 --> 00:21:10.270
meant to say, really. Yeah.

483
00:21:10.750 --> 00:21:12.950
Andrew Dunkley: Well, when you look at Jupiter, I mean, it's

484
00:21:12.950 --> 00:21:14.750
in the red spectrum too, isn't it, really?

485
00:21:15.230 --> 00:21:17.870
Professor Fred Watson: Yes, it is. It's got. Yeah. I mean, um,

486
00:21:18.190 --> 00:21:20.910
and Saturn as well. They've got colours that

487
00:21:20.990 --> 00:21:23.990
really, uh. In a sense, they're what we might

488
00:21:23.990 --> 00:21:26.390
describe as warmer colours. Although that

489
00:21:26.390 --> 00:21:28.190
doesn't. The temperature goes the other way.

490
00:21:28.190 --> 00:21:30.470
The warmth of the colour relates to something

491
00:21:30.470 --> 00:21:33.310
called the colour temperature. And the higher

492
00:21:33.310 --> 00:21:36.260
the colour temperature, the more white, um,

493
00:21:36.260 --> 00:21:38.510
and brilliant objects are, whether they're

494
00:21:38.510 --> 00:21:40.550
stars or lumps of metal or whatever.

495
00:21:41.500 --> 00:21:41.560
Andrew Dunkley: Um.

496
00:21:41.670 --> 00:21:43.670
Professor Fred Watson: But yes. So a pink one.

497
00:21:44.550 --> 00:21:47.350
The pink in a way matches

498
00:21:47.670 --> 00:21:50.150
the low temperature of this because

499
00:21:50.630 --> 00:21:52.710
anything that's glowing, um,

500
00:21:53.510 --> 00:21:55.790
would have colours that would characterise

501
00:21:55.790 --> 00:21:58.230
what its temperature is. So,

502
00:21:58.600 --> 00:22:00.830
um, I think we've solved one mystery there,

503
00:22:00.830 --> 00:22:01.350
Andrew.

504
00:22:01.510 --> 00:22:03.830
Andrew Dunkley: Maybe so. Yes. I knew we'd get somewhere

505
00:22:03.830 --> 00:22:06.830
sooner or later. We always endeavour to

506
00:22:07.470 --> 00:22:09.150
adequately deal with these issues.

507
00:22:10.430 --> 00:22:13.430
Yeah. Um, but no, it's a really fascinating

508
00:22:13.430 --> 00:22:16.430
planet and, um, well worth reading that,

509
00:22:16.430 --> 00:22:16.750
Storey.

510
00:22:17.150 --> 00:22:19.950
It's cool. It's pink. It's salty.

511
00:22:20.190 --> 00:22:22.670
I mean, that sounds very provocative.

512
00:22:23.400 --> 00:22:26.350
Professor Fred Watson: Uh, actually, it sounds like

513
00:22:26.350 --> 00:22:27.390
Scottish porridge.

514
00:22:28.590 --> 00:22:30.670
Andrew Dunkley: I've had that. I had that last year when we

515
00:22:30.670 --> 00:22:32.740
went to Edinburgh. I loved it.

516
00:22:33.060 --> 00:22:35.820
Professor Fred Watson: It's very nice. Yeah. I had my porridge this

517
00:22:35.820 --> 00:22:37.020
morning, but I put honey in it.

518
00:22:37.020 --> 00:22:38.980
Andrew Dunkley: Sorry, just reminds m. Me. They, they. They,

519
00:22:39.060 --> 00:22:41.860
um. They have a drink called salt coffee

520
00:22:42.100 --> 00:22:43.140
in Vietnam.

521
00:22:43.540 --> 00:22:44.260
Professor Fred Watson: Okay.

522
00:22:44.340 --> 00:22:47.340
Andrew Dunkley: Which is. It's to die for, is it?

523
00:22:47.340 --> 00:22:50.220
It is, yeah. We got addicted to it. We had it

524
00:22:50.220 --> 00:22:51.620
every day while we were over there.

525
00:22:51.620 --> 00:22:52.340
Professor Fred Watson: Interesting.

526
00:22:52.340 --> 00:22:53.060
Andrew Dunkley: It is, really.

527
00:22:53.300 --> 00:22:55.860
Professor Fred Watson: Is it just coffee with salt in, or.

528
00:22:55.860 --> 00:22:58.190
Andrew Dunkley: No, it's. It's a. It's a shot of coffee, uh,

529
00:22:58.260 --> 00:23:00.420
then condensed milk and then cream

530
00:23:01.340 --> 00:23:03.740
salted. And they give it to you and it comes

531
00:23:03.740 --> 00:23:05.780
in three different layers and then you just

532
00:23:05.780 --> 00:23:08.380
stir it up and drink it. And we had it iced

533
00:23:08.380 --> 00:23:09.820
because it was so hot over there.

534
00:23:09.980 --> 00:23:10.440
Professor Fred Watson: Yeah.

535
00:23:10.440 --> 00:23:12.340
Andrew Dunkley: Uh, but you can have it hot as well. It's.

536
00:23:12.340 --> 00:23:15.340
It's delicious. Yes. And then you have

537
00:23:15.340 --> 00:23:15.900
a heart attack.

538
00:23:18.300 --> 00:23:20.380
Professor Fred Watson: Yeah. Which is less. Less delicious.

539
00:23:20.380 --> 00:23:23.380
Andrew Dunkley: Yeah, yeah, yeah. No, very nice. But, um,

540
00:23:23.380 --> 00:23:24.740
there you go. If you want to read about the

541
00:23:24.740 --> 00:23:27.500
salty exoplanet, you can do that at science

542
00:23:27.580 --> 00:23:30.450
blogs. This is Space Nuts with

543
00:23:30.450 --> 00:23:32.490
Andrew Dunkley and Professor Fred Watson

544
00:23:32.490 --> 00:23:33.050
Watson.

545
00:23:34.970 --> 00:23:37.010
Professor Fred Watson: I believe that this nation should commit

546
00:23:37.010 --> 00:23:39.290
itself to achieving the goal

547
00:23:39.850 --> 00:23:42.810
before this decade is out, of landing a

548
00:23:42.810 --> 00:23:45.250
man on the moon and returning him safely to

549
00:23:45.250 --> 00:23:45.690
the Earth.

550
00:23:47.290 --> 00:23:49.760
Andrew Dunkley: Our final storey. Uh,

551
00:23:50.250 --> 00:23:52.970
Fred Watson, is about a swift mission to save

552
00:23:53.050 --> 00:23:55.690
A vital space observatory. This. This storey

553
00:23:55.690 --> 00:23:57.980
I've seen popping up a few times in recent,

554
00:23:57.980 --> 00:24:00.180
um, days. And

555
00:24:00.900 --> 00:24:03.780
it's, um. Because of the timing issue

556
00:24:03.780 --> 00:24:05.940
they've got with this, uh, they've got to act

557
00:24:06.100 --> 00:24:08.820
very swiftly to save the Swift

558
00:24:09.220 --> 00:24:10.020
observatory.

559
00:24:10.920 --> 00:24:13.300
Professor Fred Watson: Um, that's right. It's a swift storey.

560
00:24:13.780 --> 00:24:15.460
Sorry, a storey we'll cover swiftly

561
00:24:17.380 --> 00:24:20.380
at the end of the show. Um, it is. It's

562
00:24:20.380 --> 00:24:22.940
a great storey. And what's making.

563
00:24:22.940 --> 00:24:24.420
Andrew Dunkley: For all the wrong reasons, it's a great

564
00:24:24.420 --> 00:24:24.740
storey.

565
00:24:24.740 --> 00:24:26.940
Professor Fred Watson: Yes, that's right. Uh, what's making the

566
00:24:26.940 --> 00:24:29.720
headlines is that,

567
00:24:30.660 --> 00:24:33.080
uh, engineers and scientists have been able

568
00:24:33.080 --> 00:24:36.030
to do what they do, what they've done. Uh,

569
00:24:36.200 --> 00:24:39.120
and in fact, the main, uh, proponent of

570
00:24:39.120 --> 00:24:41.720
this is a company that only started in 2020.

571
00:24:42.580 --> 00:24:45.030
Uh, and so it's, um. Uh,

572
00:24:45.960 --> 00:24:48.120
basically a response to NASA

573
00:24:48.680 --> 00:24:50.600
saying, help, we need help.

574
00:24:51.000 --> 00:24:53.000
Andrew Dunkley: Somebody pitch an idea to fix this problem.

575
00:24:53.080 --> 00:24:55.240
Professor Fred Watson: Yeah. And this company, Catalyst Space

576
00:24:55.240 --> 00:24:58.000
Technologies, did so. Uh, the background

577
00:24:58.000 --> 00:25:00.510
storey here is that Swift is a satel

578
00:25:01.220 --> 00:25:03.820
which has actually been in orbit, I think,

579
00:25:03.820 --> 00:25:05.980
since the early 2000s. I can't remember the

580
00:25:05.980 --> 00:25:08.960
exact year, but, uh, it's a,

581
00:25:08.960 --> 00:25:11.800
uh, venerable spacecraft. Uh,

582
00:25:11.800 --> 00:25:13.140
its job. Yeah.

583
00:25:14.740 --> 00:25:17.380
November 2004, that was

584
00:25:17.540 --> 00:25:17.940
when.

585
00:25:17.940 --> 00:25:19.380
Andrew Dunkley: 20th of, in fact.

586
00:25:19.380 --> 00:25:21.300
Professor Fred Watson: Indeed the 20th. Lots of twos there.

587
00:25:21.860 --> 00:25:24.580
Zeros. Um, and

588
00:25:24.580 --> 00:25:27.580
Swift, Uh, so it's a spacecraft that

589
00:25:27.580 --> 00:25:30.260
has basically proved its worth in a big way.

590
00:25:30.500 --> 00:25:33.400
And it's. Its, um, mission was

591
00:25:33.400 --> 00:25:36.400
and remains to detect gamma ray

592
00:25:36.400 --> 00:25:39.080
bursts. And these are, uh, bursts of gamma

593
00:25:39.080 --> 00:25:41.760
rays, as you'd expect, that we now know, come

594
00:25:41.760 --> 00:25:44.720
from probably colliding neutron

595
00:25:44.720 --> 00:25:47.199
stars, things of that sort, really energetic

596
00:25:47.199 --> 00:25:50.180
phenomena in deep space. Um,

597
00:25:50.960 --> 00:25:52.720
they themselves have an interesting history

598
00:25:52.720 --> 00:25:54.760
because gamma ray bursts were not known

599
00:25:54.760 --> 00:25:57.520
before the 1970s. And it was when,

600
00:25:58.470 --> 00:26:00.490
uh, various agencies launched

601
00:26:01.210 --> 00:26:03.610
spacecraft that could detect gamma rays,

602
00:26:04.440 --> 00:26:07.050
uh, in order not to look at the universe,

603
00:26:07.130 --> 00:26:09.530
but to look down on the Earth to make sure

604
00:26:09.530 --> 00:26:12.450
nobody was, uh, actually breaking the

605
00:26:12.450 --> 00:26:15.100
agreements of the nuclear test, uh,

606
00:26:15.130 --> 00:26:17.980
treaty, uh, and basically, um,

607
00:26:18.570 --> 00:26:21.170
doing nuclear testing in the atmosphere. That

608
00:26:21.170 --> 00:26:22.970
was what it was all about. It was to guard

609
00:26:22.970 --> 00:26:25.730
against, uh, maverick nuclear

610
00:26:25.730 --> 00:26:28.320
tests in the Earth's atmosphere. But it

611
00:26:28.320 --> 00:26:29.880
didn't discover any of those. But it did

612
00:26:29.880 --> 00:26:32.480
discover a whole new cosmic phenomenon. And

613
00:26:32.480 --> 00:26:34.120
the thing about gamma ray bursts is

614
00:26:35.560 --> 00:26:38.440
gamma rays itself don't tell you much

615
00:26:38.600 --> 00:26:41.040
about it except what

616
00:26:41.040 --> 00:26:43.840
direction this thing lies in. And

617
00:26:43.840 --> 00:26:46.560
so, uh, Swift, and its name is very well

618
00:26:46.560 --> 00:26:49.440
chosen, was a spacecraft that was designed to

619
00:26:49.440 --> 00:26:52.360
give swift measurements, uh, to

620
00:26:52.440 --> 00:26:54.960
the astronomical world so that they could

621
00:26:54.960 --> 00:26:57.960
very quickly turn their visible light

622
00:26:58.340 --> 00:27:01.020
and radio telescopes onto the place where

623
00:27:01.020 --> 00:27:03.580
this gamma ray burst had emitted and

624
00:27:03.580 --> 00:27:06.460
essentially sense an afterglow, what we

625
00:27:06.460 --> 00:27:09.180
call the optical counterpart in the case of

626
00:27:09.180 --> 00:27:11.060
visible light. And it's the optical

627
00:27:11.060 --> 00:27:12.940
counterpart that lets you do the

628
00:27:12.940 --> 00:27:14.380
astrophysics. It lets you make the

629
00:27:14.380 --> 00:27:15.980
measurements that you need to know how far

630
00:27:15.980 --> 00:27:18.260
away it is and what's been going on there.

631
00:27:18.660 --> 00:27:21.420
Uh, it's been a long time coming, our

632
00:27:21.420 --> 00:27:23.540
understanding of what's really going on with

633
00:27:23.540 --> 00:27:25.460
gamma ray bursts for a long time, they're a

634
00:27:25.460 --> 00:27:28.380
complete mystery. Anyway, Swift as a

635
00:27:28.380 --> 00:27:31.200
satellite has got fabulous track record,

636
00:27:31.840 --> 00:27:34.240
but it does not boast

637
00:27:34.800 --> 00:27:37.080
in its retinue, uh, of instruments, it

638
00:27:37.080 --> 00:27:39.760
doesn't boast any thrusters. Uh,

639
00:27:40.320 --> 00:27:43.120
and yeah, it does seem like in modern,

640
00:27:43.200 --> 00:27:45.200
you know, our modern understanding of the way

641
00:27:45.200 --> 00:27:47.040
you put a satellite into orbit. You want to

642
00:27:47.040 --> 00:27:49.320
have something that will actually let you

643
00:27:49.320 --> 00:27:52.040
shift its position or its height, even if

644
00:27:52.040 --> 00:27:53.600
it's only to get out of the way of the

645
00:27:53.600 --> 00:27:55.680
nearest Starlink spacecraft that's going to

646
00:27:55.680 --> 00:27:58.640
collide with it if you don't. So, um,

647
00:27:58.880 --> 00:28:00.920
it doesn't have thrusters. It would belong to

648
00:28:00.920 --> 00:28:03.820
an earlier E. And of course

649
00:28:03.820 --> 00:28:06.140
its initial orbit I think was

650
00:28:06.640 --> 00:28:08.060
um, something like

651
00:28:09.620 --> 00:28:12.420
uh, getting on for 600 kilometres. That was

652
00:28:12.420 --> 00:28:14.900
its early orbit, 585

653
00:28:14.900 --> 00:28:17.740
kilometres above Earth. But

654
00:28:17.980 --> 00:28:20.980
over the decades, uh, and there have been

655
00:28:20.980 --> 00:28:23.780
a couple of them, uh, that

656
00:28:23.780 --> 00:28:26.260
orbit has deteriorated because even at that

657
00:28:26.260 --> 00:28:27.900
height there is still

658
00:28:29.150 --> 00:28:31.470
a trace, excuse me, a trace of the Earth's

659
00:28:31.470 --> 00:28:34.190
atmosphere. And so

660
00:28:34.190 --> 00:28:37.150
that trace uh, of atmosphere is enough

661
00:28:37.150 --> 00:28:40.150
to break the spacecraft. B R A K E not B R

662
00:28:40.150 --> 00:28:43.150
E A K uh, which will slow it down

663
00:28:43.310 --> 00:28:45.750
and of course as you slow it down it

664
00:28:45.750 --> 00:28:47.990
descends and as it descends it hits more

665
00:28:47.990 --> 00:28:50.110
atmosphere which slows it down even more and

666
00:28:50.110 --> 00:28:52.310
then it descends even more. And you're on

667
00:28:52.310 --> 00:28:54.670
this pathway to ah, a re entry.

668
00:28:55.170 --> 00:28:58.080
Um, it's currently I uh, think,

669
00:28:58.450 --> 00:29:01.200
uh, flying at 363

670
00:29:01.200 --> 00:29:03.800
kilometres. So that's quite a long way down.

671
00:29:03.800 --> 00:29:05.960
Andrew Dunkley: That's a big deterioration in its orbit.

672
00:29:05.960 --> 00:29:08.480
Professor Fred Watson: It is, that's right. And that deterioration

673
00:29:08.560 --> 00:29:11.200
will not just continue, it will increase

674
00:29:11.520 --> 00:29:14.240
as it experiences a thicker atmosphere.

675
00:29:14.240 --> 00:29:17.080
It's not helped actually by the fact that the

676
00:29:17.080 --> 00:29:19.840
sun's been pretty active uh, over

677
00:29:20.000 --> 00:29:22.440
recent years. We've seen a lot of solar

678
00:29:22.440 --> 00:29:24.960
flares and um, um, coronal mass

679
00:29:24.960 --> 00:29:27.840
ejections and things of that sort. Uh and we

680
00:29:27.840 --> 00:29:30.480
know that as the subatomic

681
00:29:30.480 --> 00:29:32.840
particle flux from the sun increases, which

682
00:29:32.840 --> 00:29:35.640
it does in these events, it tends to

683
00:29:35.720 --> 00:29:38.240
kind of fluff up the Earth's atmosphere. Uh,

684
00:29:38.360 --> 00:29:41.240
it raises its height. In fact, Starlink, uh,

685
00:29:41.320 --> 00:29:43.960
SpaceX fell foul of that some years ago when

686
00:29:44.600 --> 00:29:46.680
a Number of the spacecraft that they launched

687
00:29:46.920 --> 00:29:48.480
didn't uh, actually make it into orbit

688
00:29:48.480 --> 00:29:51.240
because the Earth's atmosphere was puffed up

689
00:29:51.320 --> 00:29:54.080
by solar activity. So that's been happening

690
00:29:54.080 --> 00:29:56.900
and that's increase the um, you know, the

691
00:29:57.010 --> 00:29:59.580
uh, risk of re entry for

692
00:29:59.580 --> 00:30:01.830
Swift. So along come, uh,

693
00:30:02.550 --> 00:30:04.980
um, Catalyst Space Technologies

694
00:30:05.380 --> 00:30:08.020
and said, uh, we can do it. And

695
00:30:08.180 --> 00:30:10.780
they've actually built and prepared, I think,

696
00:30:10.780 --> 00:30:13.140
along with collaborators, a spacecraft

697
00:30:13.540 --> 00:30:16.140
which will be launched, uh, actually later

698
00:30:16.140 --> 00:30:18.980
this month, I think in about five days. Uh,

699
00:30:18.980 --> 00:30:21.670
at the time we're recording this, uh, if I

700
00:30:22.540 --> 00:30:25.380
read my uh, uh, notes on

701
00:30:25.380 --> 00:30:27.150
this correctly, uh,

702
00:30:29.260 --> 00:30:31.620
it will go to orbit. It will actually be an

703
00:30:31.620 --> 00:30:34.340
air launch. One of these fairly rare launches

704
00:30:34.340 --> 00:30:36.540
where you carry a rocket underneath the belly

705
00:30:36.540 --> 00:30:38.780
of a spacecraft, uh, sorry, of an aircraft,

706
00:30:39.020 --> 00:30:41.580
take it up to 39 or 40,000ft,

707
00:30:41.820 --> 00:30:44.660
then release it, uh, and the rocket

708
00:30:44.660 --> 00:30:47.100
burn then takes it up to orbital speed.

709
00:30:47.470 --> 00:30:50.210
Um, it's a great way of

710
00:30:50.210 --> 00:30:52.050
choosing just exactly where you want to

711
00:30:52.050 --> 00:30:54.850
launch from, which often has an impact on the

712
00:30:54.850 --> 00:30:57.450
orbit that the spacecraft will go into. So

713
00:30:57.450 --> 00:30:58.330
that's what's going to happen.

714
00:30:58.650 --> 00:31:00.450
Andrew Dunkley: That's how they used to test the space

715
00:31:00.450 --> 00:31:03.330
shuttles initially and drop them

716
00:31:03.330 --> 00:31:04.810
off. Of dropping them off a plane.

717
00:31:04.970 --> 00:31:06.690
Professor Fred Watson: That's correct, they did. To get their

718
00:31:06.690 --> 00:31:09.570
landing characteristics. And actually, um, a

719
00:31:09.570 --> 00:31:11.590
company called Virgin Orbital, uh,

720
00:31:12.410 --> 00:31:15.260
run by Mr. Virgin, uh, Richard

721
00:31:15.260 --> 00:31:17.460
Branson, uh, was

722
00:31:18.020 --> 00:31:20.940
all set uh, to kind of capture that

723
00:31:20.940 --> 00:31:23.580
market, but they had a failure a few years

724
00:31:23.580 --> 00:31:25.580
ago when they tried to launch from Cornwall

725
00:31:25.580 --> 00:31:26.980
and in fact wound up the company.

726
00:31:27.600 --> 00:31:29.940
Um, so that company doesn't exist. There are

727
00:31:29.940 --> 00:31:32.700
still other companies doing the same

728
00:31:32.700 --> 00:31:35.620
sort of thing. Uh, anyway, um, we

729
00:31:35.700 --> 00:31:38.580
hope that the spacecraft

730
00:31:38.580 --> 00:31:40.820
that will be launched, which if I remember

731
00:31:40.820 --> 00:31:43.620
rightly is called Link, uh, Link,

732
00:31:43.620 --> 00:31:46.200
will link up with Swift. Swift. It will. I

733
00:31:46.200 --> 00:31:48.040
think it's got three robotic arms that will

734
00:31:48.040 --> 00:31:50.640
grab, um, onto the Swift spacecraft

735
00:31:50.960 --> 00:31:53.440
and it will then

736
00:31:54.000 --> 00:31:56.640
fire its rockets in order to push

737
00:31:57.040 --> 00:31:59.920
Swift into a higher orbit and it

738
00:31:59.920 --> 00:32:02.720
may even stay attached so that we've

739
00:32:02.720 --> 00:32:05.460
got perhaps future opportunities to uh,

740
00:32:05.460 --> 00:32:07.280
increase its orbital height again. Yeah,

741
00:32:07.360 --> 00:32:07.840
yeah.

742
00:32:07.920 --> 00:32:10.800
Andrew Dunkley: If, if they do not succeed, and I'm not going

743
00:32:10.800 --> 00:32:13.220
to, to put the mocker on them, but uh, if

744
00:32:13.220 --> 00:32:15.900
they don't, it's likely to come crashing

745
00:32:15.900 --> 00:32:18.540
down. Late 2000 and twenties, early 2000 and

746
00:32:18.540 --> 00:32:21.220
thirties. But we've got to get to it

747
00:32:21.220 --> 00:32:23.940
faster than that because once it gets within.

748
00:32:24.580 --> 00:32:26.340
Was it 300 kilometres?

749
00:32:26.340 --> 00:32:26.820
Professor Fred Watson: Yeah.

750
00:32:26.979 --> 00:32:28.020
Andrew Dunkley: All bets are off.

751
00:32:28.100 --> 00:32:30.020
Professor Fred Watson: Yes, that's right. It's too high.

752
00:32:30.020 --> 00:32:32.020
Andrew Dunkley: It's getting pretty darn close to that now.

753
00:32:32.020 --> 00:32:33.780
Professor Fred Watson: Yep, it's not far off that's right.

754
00:32:34.260 --> 00:32:36.180
Andrew Dunkley: So they have to, they have to have this

755
00:32:36.180 --> 00:32:38.770
mission up and done by.

756
00:32:39.090 --> 00:32:40.930
I think it's October, isn't it? Or something

757
00:32:40.930 --> 00:32:41.410
like that.

758
00:32:41.570 --> 00:32:44.370
Professor Fred Watson: Yes, um, that's correct. It's

759
00:32:44.370 --> 00:32:47.170
got a good deal of urgency about it.

760
00:32:47.250 --> 00:32:50.210
I think NASA is extremely

761
00:32:50.210 --> 00:32:53.130
pleased that this company's risen to

762
00:32:53.130 --> 00:32:54.980
this and been able to do it. Uh,

763
00:32:55.810 --> 00:32:58.250
and so I, uh, guess what's happened is

764
00:32:58.250 --> 00:33:00.770
they've, you know, you've built slightly

765
00:33:00.770 --> 00:33:03.290
higher levels of risk into the whole process

766
00:33:03.290 --> 00:33:05.330
of manufacturing, designing and manufacturing

767
00:33:05.330 --> 00:33:07.650
it. Uh, that would not necessarily m. Be

768
00:33:07.650 --> 00:33:10.510
acceptable, uh, if you were doing

769
00:33:10.510 --> 00:33:13.070
things the conventional way, but by cutting

770
00:33:13.070 --> 00:33:15.550
some of that risk aversion, if I can put it

771
00:33:15.550 --> 00:33:18.510
that way, um, you would save, ah, time.

772
00:33:19.710 --> 00:33:22.690
Andrew Dunkley: All right, well, we wish them well. Um,

773
00:33:22.830 --> 00:33:25.390
it's going to be exciting either way, but

774
00:33:25.390 --> 00:33:27.470
hopefully, fingers crossed, they'll be

775
00:33:27.470 --> 00:33:30.350
successful and Swift will keep on

776
00:33:30.430 --> 00:33:33.390
keeping on. Uh, we will know very, very soon.

777
00:33:34.030 --> 00:33:36.270
They've got no time to muck around with this

778
00:33:36.270 --> 00:33:38.950
one. So, uh, we'll keep our fingers

779
00:33:38.950 --> 00:33:41.890
crossed for, uh. And you

780
00:33:41.890 --> 00:33:44.000
can read all about it@, um,

781
00:33:44.650 --> 00:33:46.626
arstechnica.com a

782
00:33:46.834 --> 00:33:48.706
r s

783
00:33:48.914 --> 00:33:51.850
technica.com and that just about

784
00:33:51.850 --> 00:33:53.610
wraps it up. Fred Watson, thank you so much.

785
00:33:53.850 --> 00:33:56.050
Professor Fred Watson: Ah, it's a pleasure. It's always good to have

786
00:33:56.050 --> 00:33:58.090
some great storeys, Andrew. Yeah, that was

787
00:33:58.090 --> 00:33:59.450
fun. We usually do.

788
00:33:59.610 --> 00:34:00.490
Andrew Dunkley: Lots of fun.

789
00:34:00.490 --> 00:34:00.970
Professor Fred Watson: Yeah.

790
00:34:01.530 --> 00:34:04.360
Andrew Dunkley: And I know we're our next planet. Um, uh,

791
00:34:04.570 --> 00:34:06.010
or our next holiday we'll

792
00:34:06.090 --> 00:34:07.650
Professor Fred Watson: be going to Pink Planet.

793
00:34:07.650 --> 00:34:09.810
Andrew Dunkley: The Pink Planet. Yes, that's right. We might

794
00:34:09.810 --> 00:34:11.500
be able to get that company to build us a

795
00:34:11.569 --> 00:34:12.209
rocket catalyst.

796
00:34:12.209 --> 00:34:14.169
Professor Fred Watson: They could probably, yeah. If you told them

797
00:34:14.169 --> 00:34:15.649
now, you could be away in a couple of weeks.

798
00:34:15.889 --> 00:34:17.169
Andrew Dunkley: Could be easily, yeah.

799
00:34:17.169 --> 00:34:18.769
Professor Fred Watson: It's only 57 light years.

800
00:34:19.930 --> 00:34:22.289
Andrew Dunkley: Uh, well, you know, plenty of time to sleep,

801
00:34:23.569 --> 00:34:26.390
probably. Permanent sleep. Never mind. Um,

802
00:34:26.449 --> 00:34:27.969
thank you, Fred Watson. We'll catch you next

803
00:34:27.969 --> 00:34:28.289
time.

804
00:34:28.910 --> 00:34:30.649
Professor Fred Watson: Uh, it's a great pleasure, Andrew. See you

805
00:34:30.649 --> 00:34:30.929
soon.

806
00:34:31.409 --> 00:34:33.129
Andrew Dunkley: Professor Fred Watson Watson, Astronomer at

807
00:34:33.129 --> 00:34:35.249
large. Don't forget to visit us, uh, online

808
00:34:35.489 --> 00:34:35.889
between

809
00:34:36.129 --> 00:34:38.729
episodes@spacenutspodcast.com or

810
00:34:38.729 --> 00:34:41.689
spacenuts IO and you can

811
00:34:41.689 --> 00:34:43.399
leave messages through the Ask me anything,

812
00:34:43.469 --> 00:34:45.909
anything button or visit the shop or become a

813
00:34:45.909 --> 00:34:48.069
supporter or whatever you like, or just have

814
00:34:48.069 --> 00:34:50.349
a look around. The, uh, shop's lots of fun.

815
00:34:50.429 --> 00:34:53.109
Just pop in there, browse. You won't be able

816
00:34:53.109 --> 00:34:55.909
to say no. And, uh, thanks to Huw in the

817
00:34:55.909 --> 00:34:58.029
studio who couldn't be with us today because

818
00:34:58.829 --> 00:35:01.629
he wasn't swift enough. Boom, boom.

819
00:35:02.349 --> 00:35:04.709
From me, Andrew Dunkley. Thanks for your

820
00:35:04.709 --> 00:35:06.469
company. We'll see you on the next episode of

821
00:35:06.469 --> 00:35:09.469
Space Nuts. Bye. Bye. You've

822
00:35:09.469 --> 00:35:11.269
been listening to the Space Nuts

823
00:35:11.269 --> 00:35:11.869
Andrew Dunkley: podcast,

824
00:35:13.760 --> 00:35:16.240
Andrew Dunkley: available at Apple Podcasts, Spotify,

825
00:35:16.400 --> 00:35:19.160
iHeartRadio, uh, or your favourite podcast

826
00:35:19.160 --> 00:35:20.920
player. You can also stream on

827
00:35:20.920 --> 00:35:23.880
demand@bytes.com. um, this has been another

828
00:35:23.880 --> 00:35:25.920
quality podcast production from

829
00:35:25.920 --> 00:35:27.120
bytes.um.com.