Interstellar Inquiries: Hot Jupiters, Rocket Fuel Solutions & Debunking the Artemis Conspiracy

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Andrew Dunkley: Hello again. Thank you for joining us on

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another episode of Space Nuts. This is a Q

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and A edition where we take audience

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questions, we write them on a piece of paper

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and then we throw it in the bin. Or we

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could answer them. We'll do the latter. Uh,

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we got questions about ultra hot

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Jupiters. We've also got questions about,

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uh, reusing spent rocket fuel. How would

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you do that? That is the question. And

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wow, how about this one? Uh, some conspiracy

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with the Artemis 2 mission

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being fake. We'll deal with all of that on

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this episode of space nuts.

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Generic: 15 seconds. Guidance is internal.

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10, 9. Ignition

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sequence start.

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Jonti Horner: Uh, space nuts.

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Generic: 5, 4, 3, 2, 1. 3, 4, 5,

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5, 4, 3, 2', 1.

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Jonti Horner: Space nuts.

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Generic: Astronauts report. It feels good.

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Andrew Dunkley: And joining us to try and sort all that out

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is Jonty Horner, professor of Astrophysics at

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the University of Southern Queensland.

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Jonty, hello.

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Jonti Horner: Good afternoon. How are you?

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Andrew Dunkley: I'm, um, all right. Um, please forgive me if

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there's some background noise. There's a

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gardener working, uh, just out the front, and

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he's, uh, doing a fabulous job. But he's

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using that kind of equipment that you would,

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um, you know, demolish a building with.

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So, uh, it's, um, it's making

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quite a noise. But, um, I've got my filter

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turned on, so hopefully it'll just keep it

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blocked out.

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Jonti Horner: Oh, it's amazing just how well these things

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work. I use this microphone in front of me

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for my teaching. I've had a number of

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occasions where the dog has decided that I'm

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painting too much attention to my students

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and not enough to her. And it's got quite

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vocal about that lying just behind me here

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next to her fire at the minute, keeping her

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really happy. And they say, no, we can't hear

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anything. It's amazing how well it can filter

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out the background noise.

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Andrew Dunkley: Yeah, the technology is amazing today. It's

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like the telescope technology that exists now

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where you can filter out light pollution.

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I don't know how that works, but, uh, it's

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quite incredible these days. Works really

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well. I want to answer some questions.

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Jonti Horner: Of course.

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Andrew Dunkley: All right, let's start with David, who's on

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the Sunshine coast in Queensland, Australia.

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David: G', day, David from the sunny coast again. I,

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uh, just had a question regarding the, uh,

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ultra hot Jupiter article from the latest,

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uh, podcast. Um,

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in the conversation, Fred Watson, uh,

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mentioned that, uh, the belief is

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that stars and their surrounding planets all

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form from the same, uh, disc of material.

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Um, I just had a question regarding the

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material. Um, you know, we tend to

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think of stars as Helium or hydrogen or both,

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um, and everything else as metals. And we

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believe those metals formed within stars,

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uh, due to the

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fusion burning. Um, where then

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does this material come from in the disc to

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form a star and its planets? Is that from

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material from. Do we believe it's material

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from another star or, um, is there some

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other process going on? Thanks very much for

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the show. Awesome. See you guys.

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Andrew Dunkley: See you, David. Thank you very much. Um, that

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sounds like it's right up your alley.

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Jonti Horner: It is. It's a good film to start off with.

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Sah. Uh, you're right. The

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material that forms a star and its planets

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has been contributed to by many previous

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stars. If you imagine after the Big Bang, the

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universe was hydrogen and helium and a tiny

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little bit of other stuff, but it really was

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barely any, which meant that a generation of

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stars formed that were pretty much just

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hydrogen and helium and very little else.

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Those stars in the early universe, there's

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some speculation that they may have been,

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including mega megastars, much

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bigger than something called the Eddington

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Limit, which is a maximum size a

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stable star can form, um, because of how

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dense the universe was at the time, how much

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material there was. So speculation of stars

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up to several thousand solar mass. Those

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stars lived fast, died young, put

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material back out into the cosmos. So they,

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when they died, they locked some of the stuff

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up in the remnants to the left, whether

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that's a black hole, a neutron star, a white

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dwarf, whatever. But the material that was

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flung outwards to form planetary nebulae,

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supernova remnants, disperses into the

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wider galaxy. So what's happening over

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the aeons of time since the Milky Way formed

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is that stars are born, live and

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die. And when they die, they pollute the

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cosmos. Stars of different masses throughout

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different things. But what that means is that

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you gradually get more and more heavy

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elements introduced into the galaxy.

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And, um, that goes to basically contributing

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to the composition of the gas and dust that

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floats around in our galaxy. If you go out,

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particularly this time of year in the

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Southern Hemisphere. But if you go out on any

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night of the year where you can see the Milky

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Way, you'll see that in the band of the Milky

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Way, there are dark patches as well as

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glowing bits. The dark patches are not

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places where there is a lack of stars, but

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rather they're places where you've got huge

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clouds of gas and dust that are opaque, that

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are blocking the light from stars that are

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more distant from reaching us. So they look

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dark in the same way that a cloud blocking

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the sun will look dark in the daytime. It's

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blocking light from beyond. These clouds

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can be vast and they're made of gas and dust

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and ice, mainly hydrogen and

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helium, but lots of other stuff. And that

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other stuff will vary from one cloud to the

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next to some degree, based on what it has

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been polluted with. You'll have to some

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degree a stirring, a pollution of the galaxy

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that gives you a background increase in the

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amount of metals. But you'll also get local

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variation. We see all of this

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incidentally in the Earth and the solar

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system. There are suggestions that the solar

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system, when it was young, when it was

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forming, was polluted by a nearby supernova

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that injected a lot of very short lived

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radioactive aluminium isotopes that

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accelerated the degree of melting you got in

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the rocky objects. There's a signature there

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of a radioisotope that is so short

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lived, there shouldn't really have been any

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of it around, unless a supernova exploded

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nearby to pollute our disc, giving us a

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slightly unusual composition. There is also

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an argument that the Earth is richer

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in gold than it should be, because

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sometime between 10 and 100 million years

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before the formation of the Earth, 10,000

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light years from where we formed, two neutron

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stars collided, polluting the universe with

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gold. And some of that gold made its way into

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the disc that formed the solar system, got

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incorporated into the Earth. And that's why

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we are a particularly good place for

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Goldfinger to, uh, have his little layer.

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We've got more gold than normal.

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Andrew Dunkley: Yeah.

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Jonti Horner: What this all means is that those giant

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clouds of gas and dust in space can be truly

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vast. When they get nudged and start to

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collapse, they'll fragment in their interiors

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to form a cluster of stars, a number of

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stars, which form from the little denser

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bits. It's like driving through a fog bank.

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Fog banks are never one uniform density.

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There's denser patches and less dense

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patches. A denser patch in one of these

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clouds will collapse under its own gravity.

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And so you'll get lots of stars forming. As

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that material collapses in, it collapses down

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to form a disc around that young protostar

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that's forming. And the star and the

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disc are made of the same material. They're

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forming from the same material. All that

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material that was in the cloud from which

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they're formed, which has been polluted over

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many generations of stars, cooking the

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books to give the composition that is uniform

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across that star system. What happens then is

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that the star forms from everything, so it

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ends up very rich in hydrogen and helium.

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Because even after all that pollution and all

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that evolution, hydrogen and helium still

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make up something like between 98 and 99% of

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all atoms in the universe. So the star is

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going to be primarily hydrogen and helium

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with a thin veneer of everything else. In

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other words, the abundance of material in the

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star is going to be very nearly

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identical to the disc. Star will end

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up being very, very, very slightly enriched

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in the heavier elements, because from

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the disc, particularly when the disc is

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cleared, there will be some infall of rocky

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and icy objects like the Kreutz sun, grazing

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comets, we see that fall into the star and

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pollute it further. But that' very, very

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small effect compared to the overall mass of

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the star. The planets form in the

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disc in the main

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form through a process we call core

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accretion. There are some suggestions that

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some of the most massive stars can form

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through a process of instability. And those

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planets and binary stars would form with a

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more stellar composition, I.e. lots of

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hydrogen, helium. But most planets

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will form by initially growing a core of

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solid material, because when you have a low,

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uh, mass, you can't capture gas,

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and so therefore your composition will be

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dominated by the solid material, not the

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gases. So that's why the Earth doesn't have

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free hydrogen and helium. We simply don't

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have enough mass to capture those gases and

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hold onto them. So even though 99% of all

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atoms in the protoplanetary disc were

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hydrogen and helium, we didn't get any of

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them, other than the old tiny little atom

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that was captured in a cage of other

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compounds called clathrate,

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that was captured in a mineral effectively.

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So we barely got any of those materials

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because we couldn't hold onto them. We formed

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out of the solid stuff. The further you are

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from the star, the colder it is, so the more

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different things can be solid rather than

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gas, which is where we get the idea of the

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ice line. If you're far enough from the star,

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water can be solid, can be ice, and then

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suddenly you've got a lot more solid material

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because water's about the most common

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compound there is, almost it's the most

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common atom, hydrogen, and the third most

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common atom, oxygen. And you put them

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together and you've got water. So beyond the

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ice line, you've got a lot more solid, and

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you can form planets much quicker, which is

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why we think Jupiter and Saturn got so big so

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quickly. They had a lot to feed on. And

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eventually they got massive enough that their

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gravity was strong enough to hold onto the

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hydrogen and helium around them and devour

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it. So they are

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in composition much more similar to the sun

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than the, uh, Earth. Is because they have all

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that hydrogen and helium, but they are still

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richer in solid material than the sun

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because at their core, there was all the

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solid material needed to build up before they

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could gather the hydrogen and helium. So they

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started with more solids. Effectively.

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The Earth doesn't really have the hydrogen

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and helium. So all of the objects in our

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solar system will have the same composition

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as the sun in terms of the balance between

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carbon and nitrogen and iron and all these

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elements, except for where they weren't able

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to capture those elements because they

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weren't massive enough. So the Earth doesn't

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have the same composition as the sun in terms

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of hydrogen and helium, but it does in terms

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of iron, nickel, all those things,

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the balance between iron and nickel and

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carbon and all the rest of it are all in the

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same ratios as the sun, um, to an

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incredibly high precision. And that's because

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we all formed from the same material that

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quite rightly was mentioned in the question

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was delivered by past generation of stars

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that had lived and died. And that's where the

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whole concept that we are stardust comes

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from. It's the idea that all the atoms that

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we need to make us, us, other than the

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hydrogen atoms, were cooked in the furnaces

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of stars long de. All the carbon, the

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nitrogen, the oxygen, the phosphorus, all

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those wonderful things, calcium, that

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contributes to our bones are all stardust

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from stars that died long before the solar

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system formed.

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Andrew Dunkley: There you are, David. Um, a very

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good, uh, answer. That pretty m. Well, nails

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it. I like the bit about there being more

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gold on Earth than there probably would be in

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other places.

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So that's. That was a lucky break for us.

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Jonti Horner: Absolutely. So useful for a

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lot of the technology we use. Not just for

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those who are sparkly, bangly things, but,

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you know, there's a lot of those rarer type

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things that are so vital to our technological

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growth that are all linked to our ancient

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heritage.

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Andrew Dunkley: Yeah, yeah. Um, well,

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there's gold, there's lithium.

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There's just so many of them. But we've got a

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lithium mine just down the road from us,

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actually.

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Jonti Horner: And that lithium, probably all primordial,

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the lithium in the universe, is almost

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certainly, almost all leftovers from the Big

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Bang.

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Andrew Dunkley: Wow, that's interesting. There you go,

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David, thanks for the question. Lovely to

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hear from you. Hope all is well on the

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Sunshine Coast. This is Space Nuts with

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Andrew Dunkley and Jonty Horner, A

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Q and A Edition.

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Generic: Roger, your lab is right here.

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David: Also Space Nuts.

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Andrew Dunkley: And we're with Professor Jonty Horner today

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with Fred Watson away. Uh, let's Go to our,

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uh, next question. Jonty, this one comes from

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Mark.

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Mark: Hi, it's Mark from Sunny Siddlesham in the

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uk. I've eventually plugged up the courage to

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send in an audio question, so here goes. You

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quite often mention water ice and the

330
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possibility of turning this into rocket fuel.

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So my what do you think? Sort of question is,

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when you use hydrogen and oxygen as a rocket

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fuel, it must turn back into water ice in

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space. So do you think it would be possible

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to collect it and reuse it through the rocket

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engine, again massively reducing the amount

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of fuel you would need to carry for an

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extended journey, say, to Mars? I've sort of

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drawn up an idea, but what do you think? Once

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again, keep up the great work, Mark from the

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uk.

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Andrew Dunkley: Thank you, Mark. It's an interesting idea.

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My, uh, first thought when I

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first heard the question was, um,

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how would you collect it? That

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might be the first challenge.

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Jonti Horner: That would be a bit of a challenge. I mean,

348
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the thing is, your exhaust is being pushed

349
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out of the bucket, the rocket, at very high

350
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speed in a very dispersed form. Now the

351
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rocket's going forward because you're

352
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throwing the things out the back. You've got

353
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the momentum, um, being transferred and it's

354
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equivalent, I guess, to you. The way I'd

355
00:13:46.030 --> 00:13:48.190
visualise this is imagining, again, sitting

356
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on an ice rink on a wheelie chair. So you've

357
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got no friction whatsoever, really slippy and

358
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you're holding, Normally, I'd just say one

359
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medicine ball, but instead imagine that

360
00:13:56.990 --> 00:13:59.710
you're holding a big bag of short puts. You

361
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throw a short put away from you and you'll

362
00:14:01.510 --> 00:14:03.070
recall in the other direction. You throw

363
00:14:03.070 --> 00:14:04.510
another short put and you'll speed up and

364
00:14:04.510 --> 00:14:06.190
you'll move in the opposite direction to the

365
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direction your short puts are going. So

366
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that's how you'll work. And that's

367
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essentially what you're doing with the

368
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rocket. You're pushing material out of the

369
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back and you're moving the opposite way,

370
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because overall, the momentum is conserved

371
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between the stuff going one way and you going

372
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the other. The problem with the

373
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rocket itself capturing its own exhaust,

374
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pumping it back in and reusing it, is

375
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then you're taking that momentum and bringing

376
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it back to you, which means you're getting

377
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pulled back towards it and you'll end up

378
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having gone nowhere to some degree.

379
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So imagine now that situation with the short

380
00:14:36.710 --> 00:14:39.590
puts on the I shrink, but

381
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instead you've got a really efficient bungee

382
00:14:42.030 --> 00:14:43.630
cord, so that when you throw them away, they

383
00:14:43.630 --> 00:14:45.910
bounce back and you catch them again. What'll

384
00:14:45.910 --> 00:14:47.390
Happen is as they're moving away from you,

385
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you'll wheel away from them. And then as they

386
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get pulled back towards you, you get pulled

387
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back towards them and you end up where you

388
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started from. Here will know a little bit of

389
00:14:54.870 --> 00:14:56.710
change due to friction and loss of energy and

390
00:14:56.710 --> 00:14:59.700
stuff like that. So the problem I'd have

391
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with this suggestion is not actually the idea

392
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of capturing and reusing the fuel.

393
00:15:04.330 --> 00:15:06.340
Um, I think that will be hard because the

394
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fuel will get so dispersed, so water will be

395
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scattered out there. It's just easier to go

396
00:15:09.900 --> 00:15:12.260
get a big lump of ice from somewhere than try

397
00:15:12.260 --> 00:15:14.180
and pick up individual water molecules or

398
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small grains of ice disperse over a large

399
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area. But the idea of being able to capture

400
00:15:19.300 --> 00:15:21.300
it from the same rocket and reuse it would

401
00:15:21.300 --> 00:15:23.060
get you into this problem of having to pull

402
00:15:23.060 --> 00:15:25.460
back material that you've pushed away, which

403
00:15:25.460 --> 00:15:27.220
means you'd be pulling yourself back to where

404
00:15:27.220 --> 00:15:29.700
you started from. So you can't get away, I

405
00:15:29.700 --> 00:15:32.180
think, from that momentum issue there.

406
00:15:32.580 --> 00:15:34.460
So I think it's two different things. I think

407
00:15:34.460 --> 00:15:37.420
if you had the ability to, instead of using

408
00:15:37.420 --> 00:15:39.380
hydrogen and oxygen as a fuel and burning

409
00:15:39.380 --> 00:15:42.100
them to be water, you can instead have a

410
00:15:42.100 --> 00:15:44.660
rocket fired powered by firing

411
00:15:44.660 --> 00:15:47.460
pellets of water out of the back. You could

412
00:15:47.460 --> 00:15:49.620
fire them at a target that captures them, um,

413
00:15:50.020 --> 00:15:52.380
collect them and reuse those pellets for

414
00:15:52.380 --> 00:15:53.860
something else. But that target will get

415
00:15:53.860 --> 00:15:56.020
pushed around by the arriving water pellets.

416
00:15:56.340 --> 00:15:57.860
So you'd want to be clever with that and

417
00:15:57.860 --> 00:15:59.420
you'd need to continually change its orbit

418
00:15:59.420 --> 00:16:02.410
and stuff. So in theory, potentially, you

419
00:16:02.410 --> 00:16:04.090
could gather the fuel for use on another

420
00:16:04.090 --> 00:16:06.930
rocket without it being the rocket you're

421
00:16:06.930 --> 00:16:09.210
flying that gathers that fuel. But in

422
00:16:09.210 --> 00:16:11.210
reality, you're dispersing over such a large

423
00:16:11.210 --> 00:16:14.210
area that unfortunately, it wouldn't be that

424
00:16:14.210 --> 00:16:15.850
practical anyway. Especially when we've got

425
00:16:15.850 --> 00:16:17.930
just huge lumps of ice floating around

426
00:16:17.930 --> 00:16:19.330
anyway. I mean, you and I have both been

427
00:16:19.330 --> 00:16:21.690
photographing a beautiful lump of ice flying

428
00:16:21.690 --> 00:16:23.610
through the solar system. There we go in the

429
00:16:23.610 --> 00:16:26.370
background. That's enough fuel for

430
00:16:26.530 --> 00:16:28.410
missions forevermore. If we were to go and

431
00:16:28.410 --> 00:16:30.610
mine there, and that's a lot more efficient

432
00:16:30.610 --> 00:16:33.170
to mine one big comet or

433
00:16:33.570 --> 00:16:36.090
asteroid for water ice or mine the moon for

434
00:16:36.090 --> 00:16:38.370
water ice, then try and catch it when it's

435
00:16:38.370 --> 00:16:40.490
dispersed, I think. So it's a really good

436
00:16:40.490 --> 00:16:43.250
idea. It's really good thinking. But it's

437
00:16:43.250 --> 00:16:44.530
something that wouldn't work. I think that's

438
00:16:44.530 --> 00:16:45.490
the way I'd view it.

439
00:16:47.010 --> 00:16:49.230
Andrew Dunkley: It'd be very complicated. And as you said,

440
00:16:49.230 --> 00:16:51.490
um, trying to capture it in the ship, you're

441
00:16:51.650 --> 00:16:53.330
actually propelling would be

442
00:16:53.330 --> 00:16:56.210
counterproductive. Using another

443
00:16:56.610 --> 00:16:59.410
spaceship to capture the ice after it's been

444
00:16:59.410 --> 00:17:02.300
expelled, uh, would be difficult because it

445
00:17:02.300 --> 00:17:04.340
would spread out too far. But then you're

446
00:17:04.340 --> 00:17:06.700
using the same technology

447
00:17:07.020 --> 00:17:09.820
to chase the ice that's been spent already

448
00:17:10.700 --> 00:17:13.340
and spending more to get the ice back. So it,

449
00:17:13.500 --> 00:17:15.580
yeah, It's a catch 22. It's just going to

450
00:17:15.580 --> 00:17:18.460
keep going around and around. So um,

451
00:17:19.020 --> 00:17:21.980
it makes it a little bit difficult. Uh, Mark,

452
00:17:21.980 --> 00:17:24.980
but, uh, thanks for your question, that

453
00:17:24.980 --> 00:17:26.860
was a fun one actually. But, uh, yeah,

454
00:17:26.960 --> 00:17:29.910
um, yeah, I like the way people

455
00:17:29.910 --> 00:17:32.310
think. But I, uh, suppose just to expand on

456
00:17:32.310 --> 00:17:35.310
it a bit, um, there's going to come a

457
00:17:35.310 --> 00:17:37.590
time where using those kinds of fuels

458
00:17:37.590 --> 00:17:39.310
probably won't be necessary. They're

459
00:17:39.310 --> 00:17:41.350
developing all sorts of different kinds of

460
00:17:41.430 --> 00:17:44.390
engine technology, uh, everything

461
00:17:44.390 --> 00:17:46.950
from solar sails to scramjets, and

462
00:17:48.630 --> 00:17:50.390
they don't use that kind of fuel.

463
00:17:50.390 --> 00:17:52.030
Jonti Horner: There's all sorts of things you could do. I

464
00:17:52.030 --> 00:17:54.510
mean again, going back to the Bobiverse,

465
00:17:54.510 --> 00:17:55.990
which I mentioned before, the Van Neumann

466
00:17:55.990 --> 00:17:58.820
probes going through, they used kind of um,

467
00:17:58.820 --> 00:18:01.030
ram scoots essentially initially in the book

468
00:18:01.030 --> 00:18:03.030
set. They then move on to other kind of

469
00:18:03.030 --> 00:18:05.630
speculative sci fi things. But initially the

470
00:18:05.630 --> 00:18:08.150
idea of having a fusion drive where you scoop

471
00:18:08.150 --> 00:18:10.070
up hydrogen atoms and turn them into helium

472
00:18:10.070 --> 00:18:12.630
and push them out the back where in front of

473
00:18:12.630 --> 00:18:14.870
you you deploy a big thing that gathers the

474
00:18:14.870 --> 00:18:16.510
hydrogen you're moving through. This is also

475
00:18:16.510 --> 00:18:18.750
what they did in Tau Zero by Poole Anderson

476
00:18:18.910 --> 00:18:20.550
is you know, you're moving really quickly,

477
00:18:20.550 --> 00:18:22.550
you gather hydrogen from in front of you and

478
00:18:22.550 --> 00:18:24.430
compress it like a ramjet effectively.

479
00:18:25.480 --> 00:18:26.920
There's all these kind of things, but they

480
00:18:26.920 --> 00:18:29.760
will all, unless we get to truly sci fi

481
00:18:29.760 --> 00:18:32.040
type things like warp driver albatier drives

482
00:18:32.040 --> 00:18:34.800
or whatever, which require physics to be

483
00:18:34.800 --> 00:18:36.360
somewhat different than how we can only

484
00:18:36.360 --> 00:18:39.240
understand it. You still have

485
00:18:39.800 --> 00:18:42.680
either a source of propellant which you

486
00:18:42.680 --> 00:18:44.720
then get rid of out the back one way or the

487
00:18:44.720 --> 00:18:47.720
other, or with solar sails you're using

488
00:18:47.880 --> 00:18:50.840
the stellar wind and that pushes you away.

489
00:18:51.460 --> 00:18:54.300
Um, people who are sailors can probably tell

490
00:18:54.300 --> 00:18:55.940
you a lot more about the complexity of how

491
00:18:55.940 --> 00:18:57.620
you can tack into the wind and move across

492
00:18:57.620 --> 00:18:59.460
the wind. But the wind, the solar wind is

493
00:18:59.460 --> 00:19:02.380
incredibly tenuous compared to the wind in

494
00:19:02.380 --> 00:19:03.900
the Earth's atmosphere. So you need a very,

495
00:19:03.900 --> 00:19:06.460
very big sail. And I think that will be

496
00:19:06.460 --> 00:19:08.540
somewhat limiting. If you were wanting to do,

497
00:19:09.180 --> 00:19:11.660
I guess, Star wars style dogfight manoeuvres,

498
00:19:11.660 --> 00:19:13.620
you wouldn't do that with a solar sail. So

499
00:19:13.620 --> 00:19:15.660
people will pick the right technology for the

500
00:19:15.660 --> 00:19:17.220
kind of mission that they want. And that was

501
00:19:17.220 --> 00:19:19.980
where the dawn mission which went to Ceres

502
00:19:20.300 --> 00:19:22.260
and um, Juno in the asteroid belt was really

503
00:19:22.260 --> 00:19:24.120
interesting because it used an ion drive

504
00:19:25.080 --> 00:19:27.920
where it was using I think ionised xenon. And

505
00:19:27.920 --> 00:19:30.760
um, that kind of drive achieves a much,

506
00:19:30.760 --> 00:19:33.280
much lower thrust but can operate for much

507
00:19:33.280 --> 00:19:35.080
much longer time. So it's very energy

508
00:19:35.080 --> 00:19:38.080
efficient um, but it wouldn't be any good for

509
00:19:38.080 --> 00:19:39.480
getting off the surface of the Earth. But

510
00:19:39.480 --> 00:19:41.400
it's very, very good for cruising around the

511
00:19:41.400 --> 00:19:43.720
solar system when you're not in a rush. And

512
00:19:43.720 --> 00:19:45.440
so what will happen is I think different

513
00:19:45.440 --> 00:19:48.080
people will have different types of drives

514
00:19:48.080 --> 00:19:50.600
for different types of scenario

515
00:19:51.650 --> 00:19:53.010
and choose the one that works best.

516
00:19:53.970 --> 00:19:56.290
Andrew Dunkley: Yeah but to get off the planet at the moment

517
00:19:56.610 --> 00:19:59.610
you need rockets. There's no real

518
00:19:59.610 --> 00:20:01.890
other technology that will get you out there.

519
00:20:01.970 --> 00:20:04.930
I know they've been trying um, sort

520
00:20:04.930 --> 00:20:07.730
of catapult technology uh, which

521
00:20:08.240 --> 00:20:11.050
um, could deploy satellites in the

522
00:20:11.050 --> 00:20:13.730
future. I um, think

523
00:20:13.810 --> 00:20:15.610
you'd need to be in the right place on the

524
00:20:15.610 --> 00:20:18.010
planet to take advantage of the um, rotation

525
00:20:18.010 --> 00:20:20.150
of the Earth so that you don't have to like

526
00:20:20.150 --> 00:20:22.150
you couldn't do it too far away from the

527
00:20:22.150 --> 00:20:25.020
equator, that kind of thing. But um,

528
00:20:25.020 --> 00:20:27.910
at the moment uh, yeah the um, standard

529
00:20:27.910 --> 00:20:30.710
old rocket engine is uh, the best option at

530
00:20:30.710 --> 00:20:31.150
the moment.

531
00:20:31.580 --> 00:20:33.950
Jonti Horner: Um, part of where the refuelling station idea

532
00:20:33.950 --> 00:20:36.390
around uh, the moon comes from which is if

533
00:20:36.390 --> 00:20:38.030
you have to take your fuel with you, you're

534
00:20:38.030 --> 00:20:39.430
carrying a lot of extra weight so you've got

535
00:20:39.430 --> 00:20:41.590
to burn extra fuel to carry that fuel which

536
00:20:41.590 --> 00:20:43.070
means you're carrying extra weight so you've

537
00:20:43.070 --> 00:20:44.910
got to take even more fuel to burn um, to

538
00:20:44.910 --> 00:20:46.310
carry the weight of the fuel you're carrying

539
00:20:46.310 --> 00:20:48.710
to carry the extra fuel. And so uh, it

540
00:20:48.710 --> 00:20:50.630
becomes very inefficient very quickly. So if

541
00:20:50.630 --> 00:20:52.850
instead you can small launches from Earth and

542
00:20:52.850 --> 00:20:54.650
then refuel once you're beyond the Earth,

543
00:20:54.890 --> 00:20:57.290
that's a lot more effective. And the other

544
00:20:57.290 --> 00:20:58.860
thing that people have suggested long term

545
00:20:58.860 --> 00:21:01.410
um, as a solution to get things off the Earth

546
00:21:01.410 --> 00:21:03.290
more cheaply are things like space elevators

547
00:21:04.010 --> 00:21:06.690
which are ah, probably still far science

548
00:21:06.690 --> 00:21:08.890
fiction. I don't, don't think we have the

549
00:21:08.890 --> 00:21:10.650
material science to do that nor the political

550
00:21:10.730 --> 00:21:12.810
will. I mean putting that in perspective,

551
00:21:12.810 --> 00:21:14.570
just saw the announcement this week that the

552
00:21:14.730 --> 00:21:17.450
vast inland rail project that was happening

553
00:21:17.770 --> 00:21:20.010
in Australia is no longer happening because

554
00:21:20.010 --> 00:21:22.090
it got too expensive and it's taken too long.

555
00:21:22.490 --> 00:21:24.270
And if we can't build a railway between

556
00:21:24.270 --> 00:21:26.590
Melbourne and Brisbane, it's going to be

557
00:21:26.590 --> 00:21:29.430
really hard to build an elevator between low

558
00:21:29.430 --> 00:21:31.510
Earth orbit, well between the Earth's surface

559
00:21:31.670 --> 00:21:33.910
geostationary orbit and the same distance

560
00:21:33.910 --> 00:21:36.630
beyond for the counterweight. Yeah,

561
00:21:36.870 --> 00:21:38.790
So I don't see it happening anytime soon.

562
00:21:39.349 --> 00:21:41.670
Andrew Dunkley: We can't even get a tunnel under the Blue

563
00:21:41.670 --> 00:21:43.590
Mountains between the west and Sydney.

564
00:21:44.370 --> 00:21:47.350
Uh, and that's despite the fact

565
00:21:47.350 --> 00:21:49.990
that that road is currently closed due to

566
00:21:50.070 --> 00:21:52.990
a structural failure in Victoria Pass.

567
00:21:52.990 --> 00:21:55.930
The old convict bridge, that's, uh, 200

568
00:21:55.930 --> 00:21:58.530
years old or something, or 150 years old. And

569
00:21:58.610 --> 00:22:01.170
it's finally given up the ghost. And so

570
00:22:01.170 --> 00:22:02.210
they've closed the road.

571
00:22:02.210 --> 00:22:05.210
It's. You know, people have been screaming

572
00:22:05.210 --> 00:22:08.130
for a tunnel for decades. And,

573
00:22:08.370 --> 00:22:11.329
um, no politicians willing to spend the

574
00:22:11.329 --> 00:22:12.770
money because there aren't enough people.

575
00:22:13.090 --> 00:22:14.570
Bottom line is there aren't enough people

576
00:22:14.570 --> 00:22:17.290
living west of the mountains to make it worth

577
00:22:17.290 --> 00:22:17.890
your vote.

578
00:22:18.930 --> 00:22:20.050
Jonti Horner: Really. What it comes down.

579
00:22:20.370 --> 00:22:21.490
Andrew Dunkley: That's what it comes down to.

580
00:22:21.490 --> 00:22:23.290
Jonti Horner: Reminds me of the old episode of the Simpsons

581
00:22:23.290 --> 00:22:24.890
when I was a kid with the kind of argument

582
00:22:24.890 --> 00:22:26.450
about books for the kids or something.

583
00:22:26.530 --> 00:22:28.730
There's the two people at the front room

584
00:22:28.730 --> 00:22:30.850
basically shouting, but our children, but

585
00:22:30.850 --> 00:22:33.410
taxes. But our children, but taxes. And it's

586
00:22:33.490 --> 00:22:35.090
this whole thing of everybody wants it, but

587
00:22:35.090 --> 00:22:36.210
nobody wants to pay for it.

588
00:22:36.770 --> 00:22:39.450
Andrew Dunkley: Exactly, yes. Uh, a tunnel under the Blue

589
00:22:39.450 --> 00:22:41.650
Mounds would be wonderful, though. Although,

590
00:22:41.710 --> 00:22:44.490
um, some. Some of the arguments against it

591
00:22:44.490 --> 00:22:46.130
are, uh. Well, it'll only save you 15

592
00:22:46.210 --> 00:22:48.210
minutes. I think it'd probably save you more.

593
00:22:48.370 --> 00:22:50.370
Gets pretty log jammed up over that mountain.

594
00:22:50.370 --> 00:22:52.450
Jonti Horner: We have those arguments about the Toowoomba

595
00:22:52.450 --> 00:22:54.080
bypass, and that's been a godsend.

596
00:22:54.550 --> 00:22:57.350
Andrew Dunkley: I mean, yeah, I used it last, uh, year. Yeah,

597
00:22:57.350 --> 00:22:58.110
it's fantastic.

598
00:22:58.110 --> 00:22:59.990
Jonti Horner: It fell apart and bits fell onto it because

599
00:22:59.990 --> 00:23:02.230
they contracted fairly cheaply.

600
00:23:02.590 --> 00:23:04.950
Um, but that has saved about half an hour

601
00:23:04.950 --> 00:23:06.870
from my trip down to Brisbane when I go to

602
00:23:06.870 --> 00:23:08.790
the airport and stuff because I don't have to

603
00:23:08.790 --> 00:23:10.790
go through Toowoomba and all the freight

604
00:23:10.790 --> 00:23:12.430
companies use it even though the tolls are

605
00:23:12.430 --> 00:23:15.350
quite high. Because the tolls being high is a

606
00:23:15.350 --> 00:23:16.790
lot better than the wear and tear on their

607
00:23:16.790 --> 00:23:18.150
vehicles coming up the old road into

608
00:23:18.150 --> 00:23:19.550
Toowoomba and having to stop at all the

609
00:23:19.550 --> 00:23:21.730
traffic lights and stuff. So it works out

610
00:23:21.730 --> 00:23:23.410
deeper for them. It's better for the

611
00:23:23.410 --> 00:23:25.010
Toowoomba council because they're having to

612
00:23:25.010 --> 00:23:26.450
repair less potholes and they have less

613
00:23:26.450 --> 00:23:28.490
accidents. And it's one of those things where

614
00:23:28.490 --> 00:23:29.930
it was a little controversial when it was

615
00:23:29.930 --> 00:23:32.650
being built, but since it's there, it's been

616
00:23:32.650 --> 00:23:34.770
a godsend. And I'd like to think that some of

617
00:23:34.770 --> 00:23:36.290
these big infrastructure projects would be

618
00:23:36.290 --> 00:23:38.330
the same. And I mean, a space elevator would

619
00:23:38.330 --> 00:23:40.850
be wonderful, but, you know, gonna be hard to

620
00:23:40.850 --> 00:23:42.530
persuade people to commit to building it,

621
00:23:42.530 --> 00:23:43.730
even when we get the technology.

622
00:23:43.810 --> 00:23:46.410
Andrew Dunkley: I think, uh, wait till there are

623
00:23:46.410 --> 00:23:48.930
orbiting hotels that'll change everything.

624
00:23:49.170 --> 00:23:52.030
You wait and see. Might be

625
00:23:52.030 --> 00:23:54.870
waiting a while. Um, thanks, Mark. Lovely to

626
00:23:54.870 --> 00:23:55.350
hear from you.

627
00:23:55.350 --> 00:23:58.270
This is Space Nuts with Andrew Dunkley and

628
00:23:58.270 --> 00:23:59.670
Professor Jonty Horner.

629
00:24:04.150 --> 00:24:05.190
Jonti Horner: Space Nuts.

630
00:24:05.350 --> 00:24:08.070
Andrew Dunkley: One more question, uh, Jonty. And this one

631
00:24:08.150 --> 00:24:10.230
comes from Paul.

632
00:24:10.630 --> 00:24:12.430
Joe: G', day, Fred Watson and Andrew. Paul here

633
00:24:12.430 --> 00:24:15.190
from Sunnybridge, Vegas. I have

634
00:24:15.190 --> 00:24:17.830
a question and a dirty secret that

635
00:24:18.150 --> 00:24:19.590
I need to confess.

636
00:24:21.510 --> 00:24:24.270
So I was on this Flat Earth group on

637
00:24:24.270 --> 00:24:27.110
Facebook. Yes, I know, I know. Uh, anyway,

638
00:24:27.270 --> 00:24:30.150
this guy provided some AI information

639
00:24:30.710 --> 00:24:33.710
which was absolutely correct to

640
00:24:33.710 --> 00:24:36.670
contend that there is no way that the Artemis

641
00:24:36.670 --> 00:24:38.670
mission could have ever caught up to the

642
00:24:38.670 --> 00:24:40.390
Earth because the Earth travels a hell of a

643
00:24:40.390 --> 00:24:43.190
lot faster than that little spaceship.

644
00:24:43.830 --> 00:24:46.710
I pointed out that they didn't need to

645
00:24:47.120 --> 00:24:49.160
catch up to the Earth at all. They just

646
00:24:49.160 --> 00:24:51.960
needed to point themselves to where it was

647
00:24:51.960 --> 00:24:54.000
going to be and then splash down,

648
00:24:54.880 --> 00:24:57.280
land safely, and be

649
00:24:57.360 --> 00:24:59.200
applauded by everybody except for the Flat

650
00:24:59.200 --> 00:25:02.200
Earthers like him, uh, who are absolutely

651
00:25:02.200 --> 00:25:04.800
incensed at the moment about

652
00:25:05.120 --> 00:25:07.760
how it's all fake, as per, uh, usual.

653
00:25:08.080 --> 00:25:11.000
Anyway, I told him

654
00:25:11.000 --> 00:25:13.440
that if he really wanted a better answer,

655
00:25:13.520 --> 00:25:15.480
exact answer, he really needed to talk to an

656
00:25:15.480 --> 00:25:18.080
astrophysicist. So my second question

657
00:25:18.580 --> 00:25:21.060
is. Well, my first question is, was I on the

658
00:25:21.060 --> 00:25:23.460
right track? And my second question is,

659
00:25:24.340 --> 00:25:26.980
are there any astrophysicists or any websites

660
00:25:26.980 --> 00:25:29.460
out there that can give us an animation

661
00:25:30.020 --> 00:25:32.980
of the Earth going around

662
00:25:32.980 --> 00:25:35.860
the sun that also has, uh, the

663
00:25:35.860 --> 00:25:38.420
animated version of the Artemis going around

664
00:25:38.420 --> 00:25:40.580
the moon so that we can see the whole thing

665
00:25:40.580 --> 00:25:43.460
in context in terms of the solar system, or

666
00:25:43.460 --> 00:25:45.300
at least our area of the solar system system.

667
00:25:45.720 --> 00:25:48.700
Uh, it's not going to convince him, I'm sure,

668
00:25:48.700 --> 00:25:51.540
but I think it'd be pretty cool to see

669
00:25:51.540 --> 00:25:54.300
something like that. Anyway, thanks very

670
00:25:54.300 --> 00:25:56.720
much, gentlemen, for the show, as always. Um,

671
00:25:56.720 --> 00:25:59.580
look forward to it every week and catch you

672
00:25:59.580 --> 00:25:59.940
later.

673
00:26:00.340 --> 00:26:01.140
Jonti Horner: Have a good one.

674
00:26:01.300 --> 00:26:04.100
Andrew Dunkley: You too, Paul. Thank you. If only we had

675
00:26:04.100 --> 00:26:06.980
an astrophysicist somewhere nearby.

676
00:26:07.300 --> 00:26:09.700
Jonty, any I know

677
00:26:10.420 --> 00:26:12.020
was directing the question to Fred Watson,

678
00:26:12.020 --> 00:26:13.860
but he asked for an

679
00:26:13.860 --> 00:26:15.060
astrophysicist.

680
00:26:15.300 --> 00:26:17.560
Jonti Horner: Yeah. We are legion, for we are many. There's

681
00:26:17.560 --> 00:26:19.680
plenty of us around. It, uh, was always a

682
00:26:19.680 --> 00:26:22.160
thing when I was at uni of what title you use

683
00:26:22.160 --> 00:26:23.680
for what you're studying would depend on how

684
00:26:23.680 --> 00:26:25.200
bothered you were about the conversation.

685
00:26:25.200 --> 00:26:27.320
Because if, you know, if I told someone I was

686
00:26:27.320 --> 00:26:30.040
studying physics, said very quickly, exit

687
00:26:30.040 --> 00:26:31.600
stage left, if I told them I was doing

688
00:26:31.600 --> 00:26:33.320
astronomy, they'd stay and chat. And if I

689
00:26:33.320 --> 00:26:34.960
told them I was doing astrophysics, they'd

690
00:26:34.960 --> 00:26:37.720
just look a little bit scared. Um, but I was

691
00:26:37.720 --> 00:26:38.400
doing all three.

692
00:26:39.040 --> 00:26:41.760
This is an interesting one. I mean,

693
00:26:42.870 --> 00:26:45.440
people like the flat Earthers are difficult.

694
00:26:45.440 --> 00:26:45.480
David: Ah.

695
00:26:46.070 --> 00:26:48.950
Jonti Horner: Because there is no amount of truth, no

696
00:26:48.950 --> 00:26:51.030
amount of evidence that you can put before

697
00:26:51.030 --> 00:26:52.630
people who are convinced that they've been

698
00:26:52.630 --> 00:26:55.550
lied to, um, other than talking to

699
00:26:55.550 --> 00:26:57.590
them gently about it. And it's like

700
00:26:58.070 --> 00:26:59.990
discussions of climate change I've had in the

701
00:26:59.990 --> 00:27:02.070
past with people who argue climate change

702
00:27:02.070 --> 00:27:04.790
isn't real. Arguing and fighting with people

703
00:27:05.110 --> 00:27:07.510
over this doesn't win hearts and minds. It

704
00:27:07.510 --> 00:27:09.390
just gets them more entrenched. But talking

705
00:27:09.390 --> 00:27:11.650
to them about it and talking about why we

706
00:27:11.650 --> 00:27:14.010
think something is the case, this is our

707
00:27:14.010 --> 00:27:17.010
evidence, this is what it is. That can

708
00:27:17.010 --> 00:27:18.570
be a little bit more fruitful, I guess, but

709
00:27:18.570 --> 00:27:19.890
it is really challenging. I mean, especially

710
00:27:19.890 --> 00:27:21.490
given that we had a beautiful eclipse of the

711
00:27:21.490 --> 00:27:23.730
moon just a few months ago, where you can see

712
00:27:23.730 --> 00:27:25.450
that the shadow of the Earth is round.

713
00:27:27.930 --> 00:27:30.410
Andrew Dunkley: And that's the big argument. If the Earth was

714
00:27:30.410 --> 00:27:33.130
flat, the shadow at some stage would be

715
00:27:33.130 --> 00:27:35.530
just a line across the Moon.

716
00:27:35.530 --> 00:27:38.500
Jonti Horner: We'd see the elephants in the turtle. Um,

717
00:27:38.960 --> 00:27:40.480
the other thing is, if the Earth was flat,

718
00:27:40.480 --> 00:27:41.960
the cats would have pushed everything off the

719
00:27:41.960 --> 00:27:44.800
edge by now. Yes, yes,

720
00:27:44.880 --> 00:27:47.640
that's the other one. But, uh, in terms of

721
00:27:47.640 --> 00:27:50.160
Artemis, at the end of the day,

722
00:27:50.640 --> 00:27:53.240
we know it happened because we saw it. You

723
00:27:53.240 --> 00:27:56.040
know, I was over in Europe at the

724
00:27:56.040 --> 00:27:58.800
time, and, um, my colleagues at UNISQ were

725
00:27:58.800 --> 00:28:00.680
happily sharing their own little footage of

726
00:28:00.680 --> 00:28:02.840
the spacecraft that they got from our

727
00:28:02.840 --> 00:28:05.600
telescopes. They have no reason to lie.

728
00:28:05.760 --> 00:28:08.560
They have no vested interest in this. It's

729
00:28:08.560 --> 00:28:09.960
not like they're secretly on the payroll of

730
00:28:09.960 --> 00:28:12.880
NASA, ignoring the fact that if it was faked,

731
00:28:13.440 --> 00:28:15.560
Russia and China will be racing to tell

732
00:28:15.560 --> 00:28:17.840
everybody because that will be the best PR

733
00:28:17.840 --> 00:28:20.120
victory ever. You know, I mean, it's the same

734
00:28:20.120 --> 00:28:22.720
with the Moon landings in, uh, 1969.

735
00:28:23.280 --> 00:28:25.040
Did anybody really, really think that the

736
00:28:25.040 --> 00:28:26.600
Russians would have stayed quiet if there was

737
00:28:26.600 --> 00:28:28.000
a sniff of it being faked?

738
00:28:28.960 --> 00:28:31.040
Andrew Dunkley: In fact, my great grandmother

739
00:28:32.510 --> 00:28:34.590
always thought the Apollo landings were

740
00:28:34.590 --> 00:28:37.390
faked. Uh, she absolutely refused

741
00:28:37.470 --> 00:28:40.150
to believe it. But she grew up in an era

742
00:28:40.150 --> 00:28:42.430
before flight, so

743
00:28:43.070 --> 00:28:46.070
I can understand why she would

744
00:28:46.070 --> 00:28:47.550
think that, but she just thought it was all

745
00:28:47.550 --> 00:28:50.150
just some sort of publicity stunt. But I

746
00:28:50.150 --> 00:28:51.710
don't remember what they might have been

747
00:28:52.190 --> 00:28:53.550
trying to get publicity for,

748
00:28:53.550 --> 00:28:54.910
Jonti Horner: because they beat the Russians. I mean,

749
00:28:54.910 --> 00:28:56.110
that's what it was to them. I'll beat the

750
00:28:56.110 --> 00:28:58.190
Soviets as it was then, have been pulled up

751
00:28:58.190 --> 00:28:58.910
on that a couple of times.

752
00:28:58.910 --> 00:29:00.750
Andrew Dunkley: It was definitely a big PR, um,

753
00:29:00.750 --> 00:29:03.370
Jonti Horner: exercise in that regard. Uh, a former

754
00:29:03.370 --> 00:29:05.250
PhD student who worked with me, Jake Clark,

755
00:29:05.250 --> 00:29:08.250
Dr. Jack Clark, now M, gave a wonderful talk

756
00:29:08.250 --> 00:29:10.890
a couple of times about the

757
00:29:10.970 --> 00:29:13.330
moon landings in 1969 and why they couldn't

758
00:29:13.330 --> 00:29:14.770
have been faked because we couldn't afford

759
00:29:14.770 --> 00:29:17.610
it. Talking about faking it with the

760
00:29:17.610 --> 00:29:19.209
technology we had at the time would have

761
00:29:19.209 --> 00:29:20.610
actually been more expensive than going

762
00:29:20.610 --> 00:29:23.570
there. Um, which is fairly compelling

763
00:29:23.570 --> 00:29:25.170
for me. I mean, there's always a joke that,

764
00:29:25.170 --> 00:29:26.970
you know, yeah, the moon landings were always

765
00:29:26.970 --> 00:29:28.410
going to be faked, but they hired Stanley

766
00:29:28.410 --> 00:29:29.850
Kubrick to direct and he was such a

767
00:29:29.850 --> 00:29:31.290
perfectionist that they demanded that they do

768
00:29:31.290 --> 00:29:32.740
it on site. Um,

769
00:29:34.970 --> 00:29:37.920
um, with Artemis 2, there

770
00:29:38.080 --> 00:29:40.800
is abundant evidence that it really happened.

771
00:29:41.440 --> 00:29:43.000
You could, with a small telescope or

772
00:29:43.000 --> 00:29:44.440
binoculars, go outside and see the

773
00:29:44.440 --> 00:29:46.920
spacecraft. And I mean, you can't fake that.

774
00:29:46.920 --> 00:29:48.320
It's not like we're beaming thoughts into

775
00:29:48.320 --> 00:29:49.880
your head. And if you think we are, you can

776
00:29:49.880 --> 00:29:51.440
wear some tinfoil. That's all good.

777
00:29:52.250 --> 00:29:54.920
Um, in terms of the

778
00:29:54.920 --> 00:29:56.840
argument that the Earth is going too quick

779
00:29:56.840 --> 00:29:59.670
for this thing to catch up, that is

780
00:30:00.470 --> 00:30:03.350
in the kindest interpretation of it, that

781
00:30:03.350 --> 00:30:06.190
is allowing common sense

782
00:30:06.190 --> 00:30:08.590
based on your understanding of how day to day

783
00:30:08.590 --> 00:30:10.870
life works, interfere with

784
00:30:11.590 --> 00:30:13.390
looking at how things would move through

785
00:30:13.390 --> 00:30:15.710
space. I can see why you would get to that.

786
00:30:15.710 --> 00:30:18.230
If you think about a small child running

787
00:30:18.230 --> 00:30:20.070
along with a model of Artemis in the hand and

788
00:30:20.070 --> 00:30:22.110
a Ferrari driving down the motorway, or

789
00:30:22.110 --> 00:30:23.990
insert the make of car driving down the

790
00:30:23.990 --> 00:30:26.360
motorway at 100 kilometres an hour, the child

791
00:30:26.360 --> 00:30:27.840
is not going to catch the thing because

792
00:30:27.840 --> 00:30:30.180
they're not quick enough. And there are, uh,

793
00:30:30.240 --> 00:30:32.120
limits on how fast a child can run and how

794
00:30:32.120 --> 00:30:33.640
fast the car can move to do with air

795
00:30:33.640 --> 00:30:36.240
resistance. It's

796
00:30:36.480 --> 00:30:39.000
however, almost similar to saying, you know,

797
00:30:39.000 --> 00:30:41.160
I can't throw a ball up in the air and catch

798
00:30:41.160 --> 00:30:43.640
it because I'm Moving at over 1000 kilometres

799
00:30:43.640 --> 00:30:45.800
an hour around the Earth. So I'm moving too

800
00:30:45.800 --> 00:30:48.520
fast to catch up with that ball. Doesn't work

801
00:30:48.520 --> 00:30:49.960
like that because me and the ball are both

802
00:30:49.960 --> 00:30:52.560
moving at 1000 kilometres per hour. And so

803
00:30:52.560 --> 00:30:54.560
it's a relative speed between us that

804
00:30:54.560 --> 00:30:57.080
matters. So the Earth is going around the sun

805
00:30:57.080 --> 00:30:59.120
at about 30 kilometres a second. That's

806
00:30:59.280 --> 00:31:02.280
demonstrably true. Artemis moving

807
00:31:02.280 --> 00:31:05.040
in orbit around the Earth is moving around

808
00:31:05.040 --> 00:31:07.280
the sun at 30 kilometres a second with the

809
00:31:07.280 --> 00:31:09.400
Earth. It's falling with the Earth. Uh, so

810
00:31:09.400 --> 00:31:11.360
it's a relative speed that matters.

811
00:31:12.080 --> 00:31:12.640
Andrew Dunkley: Yeah.

812
00:31:12.640 --> 00:31:14.880
Jonti Horner: Now, if I went above the Earth, onto the

813
00:31:14.880 --> 00:31:17.440
space station, but instead of orbiting the,

814
00:31:17.440 --> 00:31:19.400
uh, Earth and falling with things, I was able

815
00:31:19.400 --> 00:31:22.310
to use rockets to stand still. Or I had

816
00:31:22.390 --> 00:31:24.910
an imaginary hovering platform of doom that

817
00:31:24.910 --> 00:31:26.630
wasn't moving. I'm, um, out of the

818
00:31:26.630 --> 00:31:28.870
atmosphere. If I threw a ball up in the air,

819
00:31:29.110 --> 00:31:30.550
it would move away from the Earth and the

820
00:31:30.550 --> 00:31:31.910
Earth's gravity would slow it down and pull

821
00:31:31.910 --> 00:31:33.470
it back, and it'd fall back down to me just

822
00:31:33.470 --> 00:31:35.190
the same as how it does on the ground.

823
00:31:36.310 --> 00:31:39.230
Now, if I was in orbit around the Earth and

824
00:31:39.230 --> 00:31:40.630
I was stood on the International Space

825
00:31:40.630 --> 00:31:42.670
Station and I tossed the ball upward, it

826
00:31:42.670 --> 00:31:44.270
would actually start moving on a different

827
00:31:44.270 --> 00:31:45.710
orbit around the Earth. So while it would

828
00:31:45.710 --> 00:31:47.510
move up, away from me and it would move down,

829
00:31:47.830 --> 00:31:49.790
it'd be going around the Earth on an orbit

830
00:31:49.790 --> 00:31:51.510
that takes slightly longer to go around the

831
00:31:51.510 --> 00:31:52.940
Earth than I do. So it also fall behind,

832
00:31:53.010 --> 00:31:54.850
behind. And that would look like wind

833
00:31:54.850 --> 00:31:57.290
resistance. But it's actually just a quirk of

834
00:31:57.290 --> 00:31:59.730
orbital mechanics in that I've put it onto a

835
00:31:59.730 --> 00:32:02.610
different orbit, um, because we are both

836
00:32:02.610 --> 00:32:05.290
falling at the time I let go of it. So if we

837
00:32:05.290 --> 00:32:07.370
imagine our flat Earther jumped off a cliff,

838
00:32:07.370 --> 00:32:09.410
and I'm not encouraging them to please do not

839
00:32:09.410 --> 00:32:11.930
do this, but imagine one jumps off a cliff

840
00:32:11.930 --> 00:32:14.090
while holding one of the shot puts from the

841
00:32:14.090 --> 00:32:16.370
previous answer without it being on a bungee

842
00:32:16.370 --> 00:32:18.930
cord. And they let go of the shot put, but

843
00:32:18.930 --> 00:32:20.890
the shot put will fall with them at the same

844
00:32:20.890 --> 00:32:23.810
speed. It won't move away from them and come

845
00:32:23.810 --> 00:32:26.330
back. It will accelerate downwards in exactly

846
00:32:26.330 --> 00:32:28.330
the same way that they do. And, uh, they'll

847
00:32:28.330 --> 00:32:30.970
only diverge once air resistance takes

848
00:32:30.970 --> 00:32:33.210
effect, depending on which of them feels more

849
00:32:33.210 --> 00:32:33.970
air resistance.

850
00:32:35.090 --> 00:32:37.210
Andrew Dunkley: It's the Galileo experiment, isn't it?

851
00:32:37.210 --> 00:32:39.010
Jonti Horner: So if you're on the space station, you throw

852
00:32:39.010 --> 00:32:40.530
a tennis ball up in the air. Ah, you're both

853
00:32:40.530 --> 00:32:42.050
actually falling, but you've changed the

854
00:32:42.050 --> 00:32:43.450
speed the tennis ball's falling, so it'll

855
00:32:43.450 --> 00:32:45.610
move away from you and not appear to come

856
00:32:45.610 --> 00:32:47.790
back because you're both still falling.

857
00:32:48.590 --> 00:32:50.630
The reason all this is relevant to Artemis is

858
00:32:50.630 --> 00:32:53.020
Artemis boosted off towards the Moon at, uh,

859
00:32:53.110 --> 00:32:55.630
a speed that was not greater than the escape

860
00:32:55.630 --> 00:32:57.950
velocity from the Earth. It was a speed that

861
00:32:57.950 --> 00:33:00.120
was high enough to get to the Moon. And, uh,

862
00:33:00.150 --> 00:33:01.830
the moon steered it around and flung it back

863
00:33:01.830 --> 00:33:04.030
towards the Earth. But then it fell towards

864
00:33:04.030 --> 00:33:06.830
the Earth under Earth's gravity, moving

865
00:33:06.990 --> 00:33:09.910
with insufficient sideward speed that as

866
00:33:09.910 --> 00:33:11.630
it fell towards the Earth, it would miss us.

867
00:33:12.340 --> 00:33:13.740
It instead was going to hit us. And they

868
00:33:13.740 --> 00:33:15.300
controlled it with rockets and stuff so that

869
00:33:15.300 --> 00:33:16.780
it entered in a controlled rather than

870
00:33:16.780 --> 00:33:19.740
uncontrolled fashion. What matters is

871
00:33:19.740 --> 00:33:21.260
not the speed the Earth's moving around the

872
00:33:21.260 --> 00:33:23.300
sun, or the speed the sun's moving around our

873
00:33:23.300 --> 00:33:25.020
galaxy, or the speed that the galaxy is

874
00:33:25.020 --> 00:33:27.899
moving through space. All that matters is the

875
00:33:27.899 --> 00:33:29.620
difference in speed between the Earth and the

876
00:33:29.620 --> 00:33:32.060
object, because they're moving together. This

877
00:33:32.060 --> 00:33:34.540
thing's speed was at no time greater than the

878
00:33:34.540 --> 00:33:36.900
escape velocity of the Earth, so it could

879
00:33:36.900 --> 00:33:38.960
never fall away from the Earth and never come

880
00:33:38.960 --> 00:33:40.480
back. It was always going to go up and then

881
00:33:40.480 --> 00:33:43.200
come down again. Unless they use rockets to

882
00:33:43.200 --> 00:33:44.880
boost it into an orbit around the moon to

883
00:33:44.880 --> 00:33:46.880
shed some of that energy, which they didn't.

884
00:33:46.880 --> 00:33:48.720
They instead slingshot it around the moon to

885
00:33:48.720 --> 00:33:51.560
come back. All of that is perfectly

886
00:33:51.560 --> 00:33:53.600
rational and straightforward given our

887
00:33:53.600 --> 00:33:55.920
understanding of physics. But it doesn't

888
00:33:55.920 --> 00:33:58.400
necessarily fit your common sense, because

889
00:33:58.400 --> 00:34:00.480
you think about throwing a ball out of the

890
00:34:00.480 --> 00:34:02.240
window of your car while your car's doing 100

891
00:34:02.240 --> 00:34:03.600
kilometres an hour and the ball will fall

892
00:34:03.600 --> 00:34:06.360
behind you and never catch you up. And so

893
00:34:06.360 --> 00:34:09.029
a lot of the arguments that

894
00:34:09.029 --> 00:34:11.469
flat Earth, uh, believers or other people in

895
00:34:11.469 --> 00:34:14.309
that kind of situation are making good faith

896
00:34:14.709 --> 00:34:16.869
are, uh, built on a faulty groundwork

897
00:34:17.829 --> 00:34:20.629
where the common sense of how they understand

898
00:34:20.709 --> 00:34:22.749
the world to work is not applicable to the

899
00:34:22.749 --> 00:34:25.080
situation they're applying it in. Um,

900
00:34:25.669 --> 00:34:27.909
and that's true of things like, you know, the

901
00:34:27.909 --> 00:34:30.589
oceans are flat. If you put a spirit level on

902
00:34:30.589 --> 00:34:32.109
them, they're flat. Well, it's actually that

903
00:34:32.109 --> 00:34:33.429
they're curved, but they're curved at such

904
00:34:33.429 --> 00:34:35.429
small level that locally they look flat.

905
00:34:36.299 --> 00:34:37.979
It's a subtle difference, but it's one that's

906
00:34:37.979 --> 00:34:39.299
easy to miss because it's hard to get your

907
00:34:39.299 --> 00:34:40.379
head around those distances.

908
00:34:41.259 --> 00:34:43.099
In terms of the animations. I just did a

909
00:34:43.099 --> 00:34:45.739
quick Google search for Artemis animation of

910
00:34:45.739 --> 00:34:48.219
orbit, and there's some beautiful. The first

911
00:34:48.219 --> 00:34:51.059
hit is a NASA flight with an annotated and

912
00:34:51.059 --> 00:34:53.779
animated path. There's a few YouTube videos,

913
00:34:53.779 --> 00:34:56.299
there is a Reddit link with an interactive 3D

914
00:34:56.299 --> 00:34:59.259
animation. There's a lot of

915
00:34:59.339 --> 00:35:01.579
little YouTube short videos that pop up

916
00:35:02.190 --> 00:35:04.590
which are not to scale, because if you make

917
00:35:04.590 --> 00:35:06.150
things to scale, the sun and the Earth and

918
00:35:06.150 --> 00:35:08.310
the Moon are points that are one pixel

919
00:35:08.310 --> 00:35:11.150
across. And, um, the spaceship is a point

920
00:35:11.150 --> 00:35:12.550
that is a pixel across as well, because

921
00:35:12.550 --> 00:35:15.540
nothing can be smaller than a pixel. Um,

922
00:35:15.540 --> 00:35:17.260
there is a fabulous thing, incidentally, and,

923
00:35:17.260 --> 00:35:18.990
um, I'm gonna see if I can find it, see if

924
00:35:18.990 --> 00:35:19.630
it's still there.

925
00:35:21.630 --> 00:35:23.830
There's this great thing called if the Moon

926
00:35:23.830 --> 00:35:26.540
were Only One Pixel. Um,

927
00:35:26.590 --> 00:35:29.150
it is. I'm gonna see if the website still

928
00:35:29.150 --> 00:35:30.830
works, because this is one of the great

929
00:35:30.830 --> 00:35:32.390
things on the Internet. Here we go. I'm gonna

930
00:35:32.390 --> 00:35:35.150
Drop it into the chat window. This, um,

931
00:35:35.390 --> 00:35:37.830
was an effort somebody made many, many, long,

932
00:35:37.830 --> 00:35:39.470
long years ago. I'll put this into the public

933
00:35:39.470 --> 00:35:41.910
chat, which never gets used. There we go. To

934
00:35:41.910 --> 00:35:44.310
visualise the scale of the solar system,

935
00:35:44.870 --> 00:35:47.670
if you made the moon one pixel across,

936
00:35:47.670 --> 00:35:49.590
so the Earth will then be two or three pixels

937
00:35:49.590 --> 00:35:52.510
across, you can, when you get bored of

938
00:35:52.510 --> 00:35:54.070
scrolling, you can click Play. But if you

939
00:35:54.070 --> 00:35:55.750
open that up and then you scroll to the right

940
00:35:55.750 --> 00:35:58.070
to explore, you move along

941
00:35:58.630 --> 00:36:00.870
and then you've got the scale. One pixel is

942
00:36:00.870 --> 00:36:03.790
3,500 kilometres, so the sun is a fairly big

943
00:36:03.790 --> 00:36:06.430
blob. And you scroll to the right from the

944
00:36:06.430 --> 00:36:08.550
sun and you've got a distance at the bottom.

945
00:36:08.870 --> 00:36:10.670
Scroll to the right a long way. We've gone 10

946
00:36:10.670 --> 00:36:12.429
million kilometres. This is this fabulous

947
00:36:12.429 --> 00:36:14.630
visualisation to let you see how big

948
00:36:15.110 --> 00:36:15.910
things are.

949
00:36:16.550 --> 00:36:17.750
Andrew Dunkley: Oh, isn't that clever?

950
00:36:17.830 --> 00:36:20.710
Jonti Horner: How fast light travels. You can click, um.

951
00:36:20.870 --> 00:36:23.800
That's slow. It's fabulous. Now what

952
00:36:23.800 --> 00:36:26.240
you can do is you can skip through.

953
00:36:26.640 --> 00:36:29.200
I need to find where there was a way to skip

954
00:36:29.200 --> 00:36:31.280
to the Earth. Yes, at the top. Skip to the

955
00:36:31.280 --> 00:36:33.200
Earth, goes whiz, whiz, whiz, whiz, whiz.

956
00:36:33.200 --> 00:36:34.960
Really quick, goes past Venus, comes to the

957
00:36:34.960 --> 00:36:37.720
Earth and the Moon. If the moon is one pixel,

958
00:36:37.720 --> 00:36:39.880
the earth is only two or three and you get

959
00:36:39.880 --> 00:36:42.400
the scale of them 8.3 light minutes out from

960
00:36:42.400 --> 00:36:44.640
the sun. And think how far you've got to

961
00:36:44.640 --> 00:36:47.520
scroll to get there. Think with that moon

962
00:36:47.520 --> 00:36:49.400
being a single pixel, how far it is from the

963
00:36:49.400 --> 00:36:52.230
Earth. This is why none of those animations

964
00:36:52.230 --> 00:36:55.190
have things to scale, because you wouldn't

965
00:36:55.190 --> 00:36:56.830
see the spacecraft, you wouldn't see the

966
00:36:56.830 --> 00:36:57.950
Earth and the moon, they wouldn't look

967
00:36:57.950 --> 00:37:00.270
pretty. So the caution there is that, uh, the

968
00:37:00.270 --> 00:37:02.390
animations that you see, even the beautiful

969
00:37:02.390 --> 00:37:05.310
NASA ones that show the flight path, are,

970
00:37:05.310 --> 00:37:07.150
ah, not to scale. And, um, that can be

971
00:37:07.150 --> 00:37:09.590
misleading. That can also

972
00:37:10.390 --> 00:37:12.110
add to some of the arguments that this is

973
00:37:12.110 --> 00:37:14.310
fake, because people say, well, the Earth and

974
00:37:14.310 --> 00:37:15.430
the Moon are much smaller than that and

975
00:37:15.430 --> 00:37:16.790
they're much further apart. Uh, that looks

976
00:37:16.790 --> 00:37:19.790
wrong. Um, so it's worth being explicit

977
00:37:19.790 --> 00:37:22.110
that these are, these visualisations are, um,

978
00:37:22.120 --> 00:37:25.040
definitively not to scale. Um, the one,

979
00:37:25.040 --> 00:37:26.800
incidentally, that was linked on the Reddit

980
00:37:26.800 --> 00:37:29.240
page looks like the dots for Earth and Moon

981
00:37:29.240 --> 00:37:30.880
actually are more to scale. So I'll just drop

982
00:37:30.880 --> 00:37:33.280
that one in as well. Not sure how this works,

983
00:37:33.280 --> 00:37:34.720
I've not really played with it. But you can

984
00:37:34.720 --> 00:37:36.240
drag the orbits around, you can move them

985
00:37:36.240 --> 00:37:38.520
back and forward in time, you can see the in

986
00:37:38.520 --> 00:37:41.360
and out of plane stuff and you can move the

987
00:37:41.360 --> 00:37:43.280
visualisation around even with the background

988
00:37:43.280 --> 00:37:45.760
stars, which is quite nice. Um, so that's

989
00:37:45.760 --> 00:37:47.360
worth a play as well. And that looks a bit

990
00:37:47.360 --> 00:37:49.880
more to scale. And there's lots of things you

991
00:37:49.880 --> 00:37:52.840
can play with, but fundamentally we

992
00:37:52.840 --> 00:37:55.360
could see it. The hardest part for me, about

993
00:37:55.840 --> 00:37:57.840
the small number of people who have argued

994
00:37:57.840 --> 00:37:59.840
that the Artemis mission didn't happen,

995
00:38:00.800 --> 00:38:02.480
is that it's something that anybody on the

996
00:38:02.480 --> 00:38:03.920
planet could see, so long as they owned a

997
00:38:03.920 --> 00:38:06.280
binoculars or a telescope. You could have

998
00:38:06.280 --> 00:38:07.400
pointed somewhere and you could see the

999
00:38:07.400 --> 00:38:10.040
capsule moving there if you really wanted. At

1000
00:38:10.040 --> 00:38:12.000
any time when the moon was above the horizon,

1001
00:38:12.640 --> 00:38:13.760
you could track it round.

1002
00:38:15.970 --> 00:38:17.730
Andrew Dunkley: And if you've got good enough gear, you can

1003
00:38:17.730 --> 00:38:19.490
actually look at the moon and see

1004
00:38:20.370 --> 00:38:23.290
the landing positions of some

1005
00:38:23.290 --> 00:38:25.570
of the Apollos. If you've got the gear.

1006
00:38:25.570 --> 00:38:26.850
Jonti Horner: If you've got the gear, I mean, that's kind

1007
00:38:26.850 --> 00:38:28.570
of spice athlete level. But what you can do

1008
00:38:28.570 --> 00:38:31.250
if you've got slightly less of the gear is

1009
00:38:31.410 --> 00:38:33.730
bounce laser pulses

1010
00:38:34.130 --> 00:38:36.290
off the retroreflectors that the astronauts

1011
00:38:36.290 --> 00:38:38.690
left at those sites and measure the distance

1012
00:38:38.690 --> 00:38:41.380
to the moon and measure its recession to an

1013
00:38:41.380 --> 00:38:43.300
incredible precision. And we can only do that

1014
00:38:43.300 --> 00:38:44.740
because people went to the moon.

1015
00:38:46.580 --> 00:38:48.660
Andrew Dunkley: Yeah, absolutely.

1016
00:38:50.660 --> 00:38:53.060
I remember the day that Neil

1017
00:38:53.060 --> 00:38:55.370
Armstrong stepped on the moon. I was, um,

1018
00:38:55.370 --> 00:38:56.420
sent home from school.

1019
00:38:59.380 --> 00:39:01.300
It's one of the strongest memories of my

1020
00:39:01.300 --> 00:39:03.510
childhood. I was seven years old and, uh,

1021
00:39:03.510 --> 00:39:06.380
I'll never forget it. It was, um, quite

1022
00:39:06.380 --> 00:39:08.680
an extraordinary thing in human history.

1023
00:39:09.080 --> 00:39:09.760
Inspirational.

1024
00:39:09.760 --> 00:39:12.600
Jonti Horner: I mean, I, I'm not old enough to have ever

1025
00:39:12.600 --> 00:39:14.200
seen anybody walk on the moon. I'm hoping

1026
00:39:14.200 --> 00:39:16.400
that'll change. But the generation of

1027
00:39:16.400 --> 00:39:19.084
astronomers who are 15,

1028
00:39:19.156 --> 00:39:21.560
20 years older than me, who were old enough

1029
00:39:21.560 --> 00:39:23.320
to see the moon landings and take them in,

1030
00:39:24.360 --> 00:39:25.960
so many people were inspired to become

1031
00:39:25.960 --> 00:39:28.720
scientists and engineers by that. We got a

1032
00:39:28.720 --> 00:39:31.680
whole generation of people across

1033
00:39:31.680 --> 00:39:34.080
the sciences, across the engineering subjects

1034
00:39:34.080 --> 00:39:37.070
that changed the world, who were all inspired

1035
00:39:37.070 --> 00:39:39.550
by seeing people walk on the moon.

1036
00:39:40.190 --> 00:39:42.110
And, um, it's kind of exciting to me, even

1037
00:39:42.110 --> 00:39:43.830
ignoring the signs, even ignoring the

1038
00:39:43.830 --> 00:39:45.510
technology, that we're going to get that

1039
00:39:45.510 --> 00:39:46.990
experience again in the coming years. If we

1040
00:39:46.990 --> 00:39:48.470
go back there, there'll be a whole new

1041
00:39:48.470 --> 00:39:50.590
generation who will change the world. All

1042
00:39:50.590 --> 00:39:52.710
inspired by those people touching down and

1043
00:39:52.710 --> 00:39:53.390
seeing it happen.

1044
00:39:54.190 --> 00:39:57.190
Andrew Dunkley: Yes, yes. I was very lucky to meet one

1045
00:39:57.190 --> 00:40:00.110
of them. Uh, Buzz Aldrin, um, some years ago,

1046
00:40:00.110 --> 00:40:03.030
came here because they built a Reutt

1047
00:40:03.030 --> 00:40:05.830
Flyer at a place called Narrowmine, just up

1048
00:40:05.830 --> 00:40:08.250
the road from here, 40 kilomet, and they took

1049
00:40:08.250 --> 00:40:10.970
it out for a fly and he came for the

1050
00:40:10.970 --> 00:40:13.650
occasion and, uh, gave A wonderful

1051
00:40:13.650 --> 00:40:16.290
speech and a, uh, handful of us in the media

1052
00:40:16.290 --> 00:40:18.930
got to interview him afterwards in a, in a

1053
00:40:18.930 --> 00:40:21.610
hangar at the same time as a helicopter

1054
00:40:21.610 --> 00:40:22.730
decided to take off.

1055
00:40:23.130 --> 00:40:24.250
Jonti Horner: That sounds about right.

1056
00:40:24.410 --> 00:40:26.970
Andrew Dunkley: He famously, you know what? You just, you

1057
00:40:26.970 --> 00:40:27.730
just go with it.

1058
00:40:27.730 --> 00:40:30.050
Jonti Horner: Oh, he very famously gave very short shrift

1059
00:40:30.050 --> 00:40:31.730
to people who told him that he'd not been to

1060
00:40:31.730 --> 00:40:32.170
the moon.

1061
00:40:32.570 --> 00:40:35.500
Andrew Dunkley: Oh, I know. Uh, Ah, yeah, I did

1062
00:40:35.500 --> 00:40:38.340
actually raise that question, but gee, it was

1063
00:40:38.340 --> 00:40:39.700
such an interesting answer.

1064
00:40:41.060 --> 00:40:42.180
Yeah, fabulous.

1065
00:40:42.230 --> 00:40:44.940
Um, Paul, great question, really

1066
00:40:44.940 --> 00:40:46.580
enjoyed that one and I,

1067
00:40:48.740 --> 00:40:51.370
I can understand your frustration, but, um,

1068
00:40:51.370 --> 00:40:53.540
maybe just avoid those Facebook pages,

1069
00:40:54.390 --> 00:40:56.540
um, because you can't, you just can't save

1070
00:40:56.540 --> 00:40:58.940
them, my friend. Uh, but good to hear from

1071
00:40:58.940 --> 00:41:00.540
you. Uh, if you've got questions for us,

1072
00:41:00.540 --> 00:41:02.420
please send them in. Uh, you can do that via

1073
00:41:02.420 --> 00:41:04.980
our website, space nutspodcast.com or

1074
00:41:04.980 --> 00:41:07.680
spacenut. You can also

1075
00:41:08.080 --> 00:41:09.920
visit us on social media. We've got the

1076
00:41:09.920 --> 00:41:11.800
official Space Nuts Facebook page and the

1077
00:41:11.800 --> 00:41:14.160
official. What's, uh, the

1078
00:41:14.480 --> 00:41:17.120
Instagram page. Uh, we've also got the

1079
00:41:17.280 --> 00:41:19.880
user group on Facebook, um, the

1080
00:41:19.880 --> 00:41:22.720
podcast group, uh, uh, which is

1081
00:41:22.720 --> 00:41:25.680
all. It's a lot of fun. It's where people who

1082
00:41:25.680 --> 00:41:28.440
listen get together, swap photos of stuff

1083
00:41:28.440 --> 00:41:30.890
they've taken in space and ask, uh,

1084
00:41:31.160 --> 00:41:34.080
questions. And, uh, it is a really good

1085
00:41:34.080 --> 00:41:37.040
group. So the Space Nuts podcast group on

1086
00:41:37.040 --> 00:41:39.820
Facebook book very much worth, uh, joining

1087
00:41:39.820 --> 00:41:42.420
that one as well and hope you'll join us

1088
00:41:42.420 --> 00:41:44.620
again real soon. And thank you to Johnny

1089
00:41:44.620 --> 00:41:46.580
Horner for filling in for Fred Watson for the

1090
00:41:46.580 --> 00:41:49.380
last month or so. It's been fantastic and

1091
00:41:49.380 --> 00:41:51.190
hopefully we can get that photography, uh,

1092
00:41:51.860 --> 00:41:53.660
special off the ground and get you back and

1093
00:41:53.660 --> 00:41:56.060
have a chat about astrophotography. Jonty,

1094
00:41:56.060 --> 00:41:57.140
that would be a real good one.

1095
00:41:57.140 --> 00:41:58.540
Jonti Horner: Fingers crossed. That would be awesome.

1096
00:41:59.500 --> 00:42:01.660
Andrew Dunkley: Yeah. All right, catch you soon. Thank you so

1097
00:42:01.660 --> 00:42:01.670
much.

1098
00:42:01.670 --> 00:42:03.340
Jonti Horner: M m. Take care. Thank you very much.

1099
00:42:04.260 --> 00:42:05.780
Andrew Dunkley: Professor Johnty Horner, professor of

1100
00:42:05.780 --> 00:42:07.780
Astrophysics at the University of Southern

1101
00:42:07.780 --> 00:42:09.700
Queensland, filling, uh, in for Fred Watson.

1102
00:42:09.700 --> 00:42:12.700
Fred Watson should be back, uh, next week

1103
00:42:12.700 --> 00:42:15.420
or later this week. I can't get my head

1104
00:42:15.420 --> 00:42:18.100
around when it'll be. It's a time slip thing.

1105
00:42:18.630 --> 00:42:20.820
Uh, but, uh, yeah, thanks to Jonty for

1106
00:42:20.820 --> 00:42:22.980
filling in and thanks to Huw in the studio,

1107
00:42:22.980 --> 00:42:25.780
who couldn't be with us today because he's

1108
00:42:25.780 --> 00:42:28.460
fake. Boom, boom. And from me, Andrew

1109
00:42:28.460 --> 00:42:30.020
Dunkley. Thanks for your company. We'll see

1110
00:42:30.020 --> 00:42:31.910
you on the next episode of Space Nuts.

1111
00:42:32.380 --> 00:42:32.580
Jonti Horner: Bye.

1112
00:42:32.580 --> 00:42:32.940
Andrew Dunkley: Bye.

1113
00:42:34.140 --> 00:42:36.340
Jonti Horner: You've been listening to the Space Nuts

1114
00:42:36.340 --> 00:42:39.340
podcast, available at

1115
00:42:39.340 --> 00:42:41.340
Apple Podcasts, Spotify,

1116
00:42:41.500 --> 00:42:44.260
iHeartRadio or your favourite podcast

1117
00:42:44.260 --> 00:42:45.980
player. You can also stream on

1118
00:42:45.980 --> 00:42:47.660
demand@bytes.um com

1119
00:42:47.979 --> 00:42:50.060
Andrew Dunkley: this has been another quality podcast

1120
00:42:50.060 --> 00:42:51.870
production from bytes.com

1121
00:42:51.870 --> 00:42:53.710
um.