Feb. 10, 2025

Cosmic Queries, Jovian Mysteries & Martian Quakes: #494 - The Great Space Q&A

Cosmic Queries, Jovian Mysteries & Martian Quakes: #494 - The Great Space Q&A

Space Nuts Episode 494: Radiation Around Jupiter, Light Refraction, and Brown Dwarfs
Join Andrew Dunkley and Professor Jonti Horner in this thought-provoking Q&A edition of Space Nuts, where they tackle a variety of intriguing questions from our...

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Space Nuts Episode 494: Radiation Around Jupiter, Light Refraction, and Brown Dwarfs
Join Andrew Dunkley and Professor Jonti Horner in this thought-provoking Q&A edition of Space Nuts, where they tackle a variety of intriguing questions from our listeners. From the complexities of radiation surrounding Jupiter to the effects of light refraction in space, and the mysteries of brown dwarfs, this episode is packed with insights that will expand your understanding of the cosmos.
Episode Highlights:
- Radiation Around Jupiter: Fenton from Minnesota dives deep into the types of radiation emitted by Jupiter and the charged particles from its volcanic moon Io. Jonti explains the implications for spacecraft navigating this hazardous environment and how these particles interact with Jupiter's magnetic field.
- Light Refraction and Redshift: Kerry from Mount Gambier wonders about the impact of gas clouds on light refraction and redshift. Jonti clarifies how light behaves when passing through these clouds and reassures listeners that the redshift measurements remain largely unaffected.
- Brown Dwarfs and Binary Systems: Nigel from Brisbane asks whether binary brown dwarfs are destined to collide. Jonti discusses the dynamics of binary systems and the various factors that could lead to such an event, while also exploring the potential for merging to create a star.
- Marsquakes and Planetary Structure: Buddy poses a fascinating question about the origins of marsquakes and whether Mars could eventually break apart. Jonti unpacks the geological processes at play on Mars and the role of Jupiter in shaping the asteroid belt.
For more Space Nuts, including our continually updating newsfeed and to listen to all our episodes, visit our website. Follow us on social media at SpaceNutsPod on Facebook, X, YouTube Music Music, Tumblr, Instagram, and TikTok. We love engaging with our community, so be sure to drop us a message or comment on your favorite platform.
If you'd like to help support Space Nuts and join our growing family of insiders for commercial-free episodes and more, visit spacenutspodcast.com/about
Stay curious, keep looking up, and join us next time for more stellar insights and cosmic wonders. Until then, clear skies and happy stargazing.
00:00 - Introduction to the episode and topics
02:15 - Discussion on radiation around Jupiter and its implications
10:30 - Light refraction and its impact on redshift
18:00 - Insights into binary brown dwarfs and potential collisions
26:45 - Marsquakes and the internal structure of Mars
30:00 - Closing thoughts and listener engagement
✍️ Episode References
Jupiter's Magnetosphere
https://en.wikipedia.org/wiki/Magnetosphere_of_Jupiter
Marsquakes Research
https://mars.nasa.gov/marsquake/
Brown Dwarfs and Binary Systems
https://en.wikipedia.org/wiki/Brown_dwarf

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WEBVTT

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Hi there, thanks for joining us.

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This is a Q and a episode of Space Nuts.

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That's me.

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That means says questions that people ask and there are

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answers that I do not give. Someone else will do that.

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But coming up we're going to We're going to get

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to something we planned to do last week, but it

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just it was a big question which required a lot

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of effort and a lot of answers and a lot

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of research. We just sort of ran out of time.

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So we'll get that one done today. From Fenton, Kerry

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is asking about the effects of light by dust clouds

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or the effects on light. Nigel is talking brown dwarfs

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and Paddy mars quakes. That's all coming up in this

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edition of Space Nuts fifteen in Channel ten nine ignition.

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Squench Space Nuts or three.

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Two Space nuts as and I report it Neils Good.

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Joining us again is Professor John D. Horner, who is

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a professor of astrophysics at the University of Southern Queensland.

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A horrible part of the world, but somebody's got to

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live there, haven't they.

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Johnny.

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Absolutely, it's drudged. It's glorious here at the minute, but

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we could do with a bit of rand that said,

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giving the amount of rent, that's something elsewhere in Australia.

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I'm probably gloved that we're not getting that. Yes, much

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much further north than you are.

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Up around the North Queensland Townsville area, it's been bucketing

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down and they've had some big floods.

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Big flood that my head around the concept of getting

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two meters of ren in a couple of days.

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Yeah, I can't. Yeah, I mean a big rain for

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us is eighty millimeters in an hour. Yeah, that's a

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big rain. I think the biggest I've ever experienced here

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was two hundred millimeters over a weekend. Yeah, that was

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some years ago and that caused big floods across the area.

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But yeah, the numbers they're talking up there are astronomical

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and your power thoughts go out.

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To everybody affected.

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Now we should get straight into Fenton's question because it's

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a big one, and we'll be back in about two

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or three als once he's finished.

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Hey, fer Andrew, this is Fenton speaking to you from

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Saint Paul, Minnesota, and you're asked on the other side

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of the planet. I got some questions for you today

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about radiation. Now, right now, we have spacecraft that are

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underway to Jupiter, and there's a lot of fretting about

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what's going to happen and how to get them to

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avoid radiation blasting off Jupiter. Well, we have three types

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of radiation alpha, beta, and gamma. If you wish, I'll

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leave that up to you to explain that to the audience.

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My question to you here is what type of radiation

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is that that's coming off of Jupiter.

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Is it just the alpha particles? In other words, just

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protons hydrogen atoms. Now here we go on to ion.

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Io is also blasting off particles from its surface as

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a result of it being volcanic. So I guess that

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means we have these charged particles coming off. Do you

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want to also include them in the term of radiation?

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Now I was also interested in what types of particles

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they have. These are metals apparently, for example, if it

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were iron then and if it were charged, then iron

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can be magnetic and that means it could possibly be

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interactive with the magnetic field of Jupiter. So where's that

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stuff going? Is it sticking along Jupiter? Is it heading

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off beyond Jupiter? Is it landing on some moons? And lastly,

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I want to ask you about a practical application for

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this now here back on Earth, we can deposit metal

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ions from the gas phase onto substrates and that has

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a lot of very useful applications. It's pretty expensive too,

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So what happens when we put a substrate in a

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way in blocking those metal ions or metal metal particles

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they are coming off of aio? Could we use that

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to deposit metals onto a surface? Just a thought. I'd

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love to hear what you think about it and what

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where you take my questions?

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Oh a great week? Why no?

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Thank you? Fenton? Always always thinking deeply?

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Is Fenton?

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These questions are always multifaceted, and that one is no exception.

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So we started off talking about the different types of

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radiation and which which kind is it's coming off Jupiter.

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Yeah, I'll dive through this set BA set, But what

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I will do initially is it's a fabulous question. There's

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a lot in here I'd recommend for the interested listener

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who wants to dig into Jupiter's.

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Environment a little bit more.

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It's a Wikipedia article about Jupiter's my magnetosphere, which is

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literally magnetosphere of Jupiter, which is incredibly thorough and detailed

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and goes into some of the things we're about to

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discuss in more detail than I will do. Now, Wikipedia's

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a fluid resource. It can be changed, so your experience

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may vary.

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But what we.

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Typically typically see is for astronomy and space subjects. They

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are not controversial, but there's enough people out there who

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are incredibly passionate about it that when an error creeps in.

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It gets fixed very quickly.

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So whilst it's not the most reliable resource, it can

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be very very good. So I do recommend looking into

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that if you want more details on some of the

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stuff we'll discuss, but I'll try and pick through the

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many things Fenton said there in turn, just to try

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and work through them if that makes sense, and hopefully

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that will be helpful. Fenton, if you're listening in. Firstly,

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when you mentioned three types of radiation, you're talking there

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about alpha, betre, and gamma, which are the kinds of

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radiation that people talk about being produced by radioactive decay.

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And they are three kinds of radiation, but they're not

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the entirety of what radiation is, and they're actually different

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kinds of thing anyway. So alpha radiation is essentially helium nuclei,

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so two protons and two neutrons stuck together coming outwards.

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That's fairly substantial particle. So that's radiation as a particle.

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So particle that's ejected in this case from a radioactive process,

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flung outwards with a certain speed, and it's carrying energy

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from one place to another in the form of the

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particle itself moving at that speed from A to B.

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Beta radiation is electrons essentially, so much less massive, typically

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traveling much faster, that are again produced by radioactivetycare quite

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often other processors. Alpha particles are positively charged because you've

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got protons in but no electrons. Beta radiation is negatively

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charged because it's got electrons in, and then gamma radiation

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is very high energy electromagnetic radiation. So that's the top

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end of the electromagnetic spectrum, which also features light that

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I'm using to look at Andrew whileye waffle away here

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and see him nodding unwisely. So there are different bits

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of radiation. Essentially, at the very simplest end, you talk

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about radiation just being energy being moved from one place

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to another, and that can be done by waves or particles.

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So a very extreme stretch, you could probably argue that

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when you go outside and you turn the hose pipe

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on and you have a jet, and that water is

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going from one pleasure another. That's form of radiation. It's

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energy being moved from one place to another. So there's

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a lot of different ways that energy can be transferred

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in this way, and light in its many forms is

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one of them. So that's everything from gamma rays at

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the high energy end to radio waves at low energy end,

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with optical and microwaven infrared in the middle somewhere. So

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there's a lot too radiation there. Now there's a couple

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of things happening with Jupiter. Firstly, you talk about the

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radiation coming off Jupiter. Now, if you think about jupe

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to the planet itself, it's sometimes said that Jupiter emits

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more energy than it receives from the Sun, and that's

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the leftover from Jupiter's form a from all the material

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coming into it, the gravitational relaxation of it. Essentially, that

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is energy emitted in the form of electromagnetic radiation. So

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light essentially of various wavelengths, it will emit as what

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we call a black body, so it'll have one particular

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color of light.

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That it emits.

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Happen most strongly, and whether you go blue or or

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reader of that color, it will emit more weakly as

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you go further away. So that's due to emitting energy,

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but it's also surrounded by an incredibly intense magnetic field,

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much stronger than the Earth's. So hop to the Earth briefly.

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One of the challenges that people face when the fly

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satellites around the Earth is that there are these radiation.

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Belts around the Earth called the Van Allen Belts, and.

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They were proposed just prior to the space age and

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then detected by the first satellites. What's going on there

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is that the Earth has a magnetic field around it

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that interacts with the magnetic field of the Sun and

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the rest of.

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The Solar system.

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And we've got this area around the Earth called the magnetosphere,

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and the magnetosphere if sculptured and shaped by what's going

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on else.

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Now.

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In the case of the Earth, you've got solar radiation

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in the form of charged particles as part of the

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solar wind buffeting against our magnetosphere, penetrating in. And when

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you have particles that have charge, whether they're positively or

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negatively charged, they interact with magnetic fields, so they will

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follow the direction of the magnetic field lines. And now

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our magnetosphere shields us from a lot of the radiation

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like that because it goes around the Earth rather than

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hitting us. But some of the radiation, in the form

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of charge particles that penetrates the ath magnetic field then

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gets trapped in the magnetic field in these belts that

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we call the Vanalon belts, which are areas where you

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have a lot of charge particles moving around at high

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speed trapped in these belts around the Earth between a

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few hundred and a few tens of thousands kilometers above

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the Earth's service. Those are areas where if you fly

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a spacecraft through there, there's a lot of charge particles

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crashing into your spacecraft at high speed that can damage

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the electronics of circuitry in particular very sensitive to this

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and gradually damage your spacecraft and take it out of operation.

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So that's the radiation environment around the Earth, and they're

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try and avoid going through the viole and belts as

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a result. Jupiter's the same. Jupiter has a much more

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intense magnetic field, so it can have a much more

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significant area of radiation belts, and those radiation belts correspond

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roughly with the location of the large moons, particularly Europa

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and Io. So in that area, when you're a spacecraft

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moving through there, you're moving through a soup of high

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speed charged particles that are continually bombarding your spacecraft, degrading it,

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damaging it, and of course they're particularly damaging to the

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electrical component ry. So you want to spend as little

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time as you can there, and that's essentially what the

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concern is for the scientists who are sending spacecraft to Jupiter.

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So that's what's going on there. Added to that, though,

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you've got the volcanism from Io, which Fenton mentions, and

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Fentin's quite right, always erupting continuously volcanically into that radiation

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environment around Jupiter, adding I think some quotes say up

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to one thousand kilos per second of new material into

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that environment. Now, the atoms that are launched out of

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Io by this volcanism are things like sulfur, oxygen, sulfur dioxide,

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all these kind of things that initially are molecules and

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atoms but are very quickly ionized, so they have an

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electron knocked off colliding with the charge particles, which certainly

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means you've got sulfur ions, oxygen ions, sodium ions, all

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floating around in a magnetic field, so I always dumping

215
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even more charged particles into that radiation. Bell those charge

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particles from ioincidentally flow along Jupiter's magnetic field lines and

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crash into the Jovian poles, creating hot spots of aurora.

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So they are aurora on Jupiter that are directly linked

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00:11:53.600 --> 00:11:56.440
to Io and to a lesser extent, Europa and Ganymat.

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You can see them if you look at aurora maps

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00:11:58.559 --> 00:12:01.120
of Jupiter that are spacecraft to seven. So you get

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this flux Taurus connecting Io to the poles of Jupiter,

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00:12:05.600 --> 00:12:08.279
which is the charged particles flowing along the magnetic fielands

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and crashing into Jupiter's poles. So that's how Io's chipping,

225
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and it's just adding more soup to the mix, essentially

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moving the metals.

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Being magnetic. I'm trying to get through all the points.

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Yeah, I just thought it was fascinating that that there's

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such an effect happening around Jupiter, and like the like,

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00:12:26.799 --> 00:12:29.200
we see similar effects with the Aurora borealis and the

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Aurora stralla, but different reasons, same effect, So you'll have.

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Aurora on Jupiter that had caused the same way as

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the aurora on Earth. But you also have Io Europe

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and Ganymede cooking their own aurora as well, So it's complicated.

235
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I think.

236
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With the metals being magnetic, there's a couple of things

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there to mention. You're entirely right that metals like iron

238
00:12:52.000 --> 00:12:55.159
and nickel can become permanently magnetized, and this is something

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00:12:55.240 --> 00:13:00.679
called ferromagnetism. Now I'm not a specialist on magnetism any means,

240
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And one of the common jokes in astronomy is if

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you want to ask a question at a conference, it's

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almost certainly have you considered magnetic fields? And the answer

243
00:13:08.240 --> 00:13:11.759
is almost certainly no, because it's just complicated. There's actually

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00:13:11.799 --> 00:13:16.440
a few types of magnetism that involves physical materials out there.

245
00:13:17.000 --> 00:13:19.799
Magnetisms are as famous. It's the one that's easy to

246
00:13:19.879 --> 00:13:24.480
observe with magnets. But that kind of interaction with magnetic

247
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field is not what we're talking about here. So we're

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not talking about solid lumps of the metal interacting with

249
00:13:29.799 --> 00:13:33.320
a magnetic field. We're talking about individual atoms and molecules

250
00:13:33.360 --> 00:13:36.799
that have been ionized and they're interacting with a magnetic field,

251
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not because they are magnetic, but because they're electrically charged.

252
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And it is a subtle difference, but it's worth flagging

253
00:13:42.159 --> 00:13:43.960
out that there are two different things there.

254
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Now.

255
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The practical application you talk about about having something there

256
00:13:48.840 --> 00:13:51.480
for all this stuff to smack into is exactly what

257
00:13:51.519 --> 00:13:54.200
they're doing. So if you've got your spacecraft with all

258
00:13:54.200 --> 00:13:56.279
this valuable electronics on it, you want it to live

259
00:13:56.320 --> 00:13:58.600
as long as possible at Jupiter does it costs a

260
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lot to get there, and they're doing two things simultaneously

261
00:14:02.639 --> 00:14:06.279
to maximize a lifetime of these missions. The first ads

262
00:14:06.320 --> 00:14:09.519
wit and therefore ads cost, but essentially for your upper clipper,

263
00:14:09.919 --> 00:14:13.120
the entire insurance suite and everything that does the science

264
00:14:13.360 --> 00:14:16.960
that they can protect is enclosed in this hard shell,

265
00:14:17.080 --> 00:14:20.000
which is made of about one hundred kilograms of titanium.

266
00:14:20.279 --> 00:14:23.519
So titanium very dense, is like a protective shield around it,

267
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I guess, serving much the same role that your windscreen

268
00:14:26.159 --> 00:14:28.440
does when you're driving through a rainstone, the water hits

269
00:14:28.480 --> 00:14:30.600
your windscreen rather than hitting you in the face.

270
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Kind of idea.

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00:14:32.279 --> 00:14:33.960
So that's part of how the solving it, which is

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00:14:34.000 --> 00:14:37.519
exactly what Fenton was talking about with having the ions

273
00:14:37.519 --> 00:14:40.960
and stuff splait into something and coating them essentially. The

274
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other thing they do is linked to bandwidth, and this

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is a perennial issue in Australia with the quality of

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00:14:45.320 --> 00:14:48.600
the National broadband Network and with things like Starlink, you

277
00:14:48.679 --> 00:14:50.960
want as much bandwidth as you can to transmit data

278
00:14:51.000 --> 00:14:54.440
around and the bandwidth you get back from Jupiter is

279
00:14:54.480 --> 00:14:57.759
pretty low because you're so far away. Basically, the further

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away you're broadcasting from, the lower your bandwidth. And it

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00:15:01.320 --> 00:15:04.960
turns out that we don't have broadcasting equipment on these

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satellites on the spacecraft strong enough to send back the

283
00:15:08.080 --> 00:15:10.840
data in real time. The rate at which you get

284
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data is much higher than the rate at which you

285
00:15:12.679 --> 00:15:15.320
can send it home. So what that means is if

286
00:15:15.360 --> 00:15:18.720
you went into orbit around Europa, you would be gathering

287
00:15:18.799 --> 00:15:21.080
data much more quickly than you can send it back,

288
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and then when your spacecraft dies, you've lost all of

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your data. So you want to maximize the amount of

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time you can spend gathering data that we get back.

291
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And the way they've solved that partially is by having

292
00:15:32.039 --> 00:15:36.320
the cladding the protection that titanium cell. But that's why

293
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they've opted to instead of orbiting Europa to move on

294
00:15:39.519 --> 00:15:43.799
a highly elongated orbit round Jupiter and have flybytes biase

295
00:15:43.799 --> 00:15:45.480
the amount of data they can gather in a one

296
00:15:45.480 --> 00:15:47.480
hour flyby, it might take them several days or a

297
00:15:47.480 --> 00:15:50.440
week to broadcast back home. If you're just sat around

298
00:15:50.480 --> 00:15:53.159
Europa waiting for that to happen, your spacecraft's getting cooked.

299
00:15:53.559 --> 00:15:55.879
But if you move on a highly elongated orbit around Jeopter,

300
00:15:55.960 --> 00:15:58.159
you spend most of your time on an elongated orbit

301
00:15:58.600 --> 00:16:00.519
near the furthest point on that orbit from the thing

302
00:16:00.559 --> 00:16:03.039
you're going around. That's when you move slowest. So you

303
00:16:03.039 --> 00:16:05.639
can have your spacecraft ducking for a very fast flyby,

304
00:16:06.120 --> 00:16:08.480
then fly back out of the radiation belt and spend

305
00:16:08.559 --> 00:16:11.200
most of its time safe and not getting cooked while

306
00:16:11.240 --> 00:16:14.559
it broadcasts back to Earth. And by doing that you

307
00:16:14.679 --> 00:16:17.799
maximize the amount of time the spacecraft can live to

308
00:16:17.919 --> 00:16:19.799
take data and give it back to you, So you

309
00:16:19.840 --> 00:16:23.279
get the maximum yield from your spacecraft, and the shielding

310
00:16:23.360 --> 00:16:27.960
just helps accentuate that. So I think Fenton have ticked

311
00:16:27.960 --> 00:16:30.000
off every point you've made there. I apologize that that

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00:16:30.159 --> 00:16:33.279
was an epic wall of verbal gibberish from me, but

313
00:16:33.320 --> 00:16:35.200
hopefully I've covered everything with a lot of John t

314
00:16:35.279 --> 00:16:35.879
wiffall there.

315
00:16:36.320 --> 00:16:41.480
Yes, indeed, now well unpecked, I will say, and thanks Fenton.

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00:16:41.559 --> 00:16:47.120
I hope we covered your questions adequately. We strive for

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adequacy here at space nets, as you know, and you

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are listening to a Q and A edition of Spacenuts

319
00:16:53.080 --> 00:16:55.519
with Andrew Ankley and Johnny Horn as.

320
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Quiet space Nuts.

321
00:17:02.799 --> 00:17:07.559
Next question comes from somebody whose name I can't find

322
00:17:07.640 --> 00:17:12.559
right at the moment, but oh it's Kerry from Mount Gambia.

323
00:17:13.559 --> 00:17:16.359
As I understand it, light refracts because the speed of

324
00:17:16.440 --> 00:17:20.240
light in matter eg. Glass is slower than in a vacuum.

325
00:17:20.440 --> 00:17:23.559
I also understand that we judge the distance slash age

326
00:17:23.559 --> 00:17:28.039
of the universe objects by addressing their light red shift.

327
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I therefore presume light refraction impacts the red shift. So

328
00:17:33.119 --> 00:17:37.279
the question is do the gas clouds in space slow

329
00:17:37.359 --> 00:17:41.319
light down i e. Impact the red shift? If yes,

330
00:17:41.680 --> 00:17:44.400
how is the impact of these dust clouds on the

331
00:17:44.440 --> 00:17:48.920
red shift we use for universal distances allowed for in

332
00:17:49.000 --> 00:17:52.559
the determining of the age of the Universe's objects.

333
00:17:53.920 --> 00:17:57.319
It's a fabulous question and a really good observation there.

334
00:17:58.200 --> 00:18:01.119
So the difference here is good to be that when

335
00:18:01.160 --> 00:18:03.319
the light enters that gas cloud, it will slow down

336
00:18:03.319 --> 00:18:05.359
a little bit. Now it's not very much because the

337
00:18:05.400 --> 00:18:07.480
density of the gas cloud is incredibly low, so it's

338
00:18:07.480 --> 00:18:10.319
a barely perceptible change. But when it leaves again, it

339
00:18:10.359 --> 00:18:13.640
will speed back up again, so there's no net impact

340
00:18:13.680 --> 00:18:16.480
on the red shift. Essentially, the light coming out of

341
00:18:16.519 --> 00:18:19.000
the gas cloud will be at the same wavelength it

342
00:18:19.079 --> 00:18:21.000
was when it went in, even though when it was

343
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going through the gas cloud it would have been slowed

344
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down a bit. The red shift itself is essentially down

345
00:18:26.559 --> 00:18:29.039
to the stretching of the universe. That's kind of how

346
00:18:29.079 --> 00:18:31.920
I always envisage it. So the more stretched the light is,

347
00:18:31.960 --> 00:18:35.160
the rhetoric gets and that is an effect that's independent

348
00:18:35.200 --> 00:18:39.440
of the material that it's going through. Now, what you

349
00:18:39.480 --> 00:18:41.720
could imagine happening is that, let's say, you know, we

350
00:18:41.720 --> 00:18:43.359
were in the middle of a dense gas cloud at

351
00:18:43.400 --> 00:18:45.839
the minute, then all of the light reaching us would

352
00:18:45.839 --> 00:18:47.799
be very slightly shifted to the red, but it would

353
00:18:47.839 --> 00:18:50.799
only be a tiny, tiny, tiny little effect, whereas the

354
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red shifts were measuring a much more substantive and much

355
00:18:53.279 --> 00:18:57.680
more substantial. So you are right that the speed of

356
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light changes as it goes through clouds, and in fact

357
00:19:00.599 --> 00:19:02.519
and I'm a little wooly on this so apologist to

358
00:19:02.519 --> 00:19:04.960
twenty radio astronomers who are listening. But I remember a

359
00:19:05.000 --> 00:19:08.519
talk a few years ago that was looking at supernova

360
00:19:08.680 --> 00:19:12.720
and things like that, and talking about getting a feel

361
00:19:12.880 --> 00:19:16.359
for the amount of gas clouds on our line of

362
00:19:16.400 --> 00:19:19.079
sight to an object, where you had an object that

363
00:19:19.079 --> 00:19:21.359
had been lensed, so you had two different images of

364
00:19:21.359 --> 00:19:24.680
the same object coming through different paths to us, and

365
00:19:24.759 --> 00:19:27.119
seeing the difference in timing of a certain event at

366
00:19:27.200 --> 00:19:30.599
radio wavelengths because one of those pasts had gone through

367
00:19:30.640 --> 00:19:32.880
more gas clouds than the other, so you have the

368
00:19:32.920 --> 00:19:36.359
same pulse arriving at slightly different times because it had

369
00:19:36.359 --> 00:19:39.160
moved slower through the gas clouds. So that's where you

370
00:19:39.200 --> 00:19:42.240
do get this effect. And I found that top fascinating,

371
00:19:42.279 --> 00:19:44.279
even though quite happily, I admit a lot of it's

372
00:19:44.319 --> 00:19:47.519
lost on me, both in time and distance in the past.

373
00:19:48.039 --> 00:19:50.039
So it does impact things there, but it doesn't really

374
00:19:50.039 --> 00:19:52.079
impact the redshift because when you leave the gas cloud,

375
00:19:52.079 --> 00:19:54.720
you speed back up, and also because a degree of

376
00:19:54.799 --> 00:19:55.960
change is very very small.

377
00:19:57.119 --> 00:20:02.200
Okay, there you go fairly answer to that one, and Carrie,

378
00:20:02.240 --> 00:20:04.920
thanks for sending it in. Let's go to our next

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00:20:04.960 --> 00:20:07.359
audio question from Nigel.

380
00:20:08.599 --> 00:20:09.480
Hi, friend and Andrew.

381
00:20:09.519 --> 00:20:11.319
This is Nigel from Brisbane, Australia.

382
00:20:11.839 --> 00:20:16.119
I recently heard a report on both Astronomy Daily and

383
00:20:16.599 --> 00:20:21.319
yourselves on Space Nuts. It was a story about a

384
00:20:21.599 --> 00:20:29.000
newly discovered binary brown dwarf system discovered. I think it

385
00:20:29.039 --> 00:20:35.279
was called Gleisa two nine to nine b Anyway, binary

386
00:20:35.319 --> 00:20:39.759
star systems got me thinking are they destined to collide?

387
00:20:40.720 --> 00:20:47.279
So should we expect the two brown dwarves to meet

388
00:20:47.319 --> 00:20:51.720
and forms one And the second question is if they

389
00:20:51.759 --> 00:20:56.200
did collide and form one star, would they be big

390
00:20:56.319 --> 00:21:03.440
enough in mass to create one start? Okay, thanks for

391
00:21:03.559 --> 00:21:06.640
taking my question, love the show, keep up the good work.

392
00:21:06.759 --> 00:21:09.880
Wait, thanks Ni, Johnny, he's just down the road from you. Johnty,

393
00:21:09.880 --> 00:21:12.319
You're not far away at all. You probably could have

394
00:21:12.359 --> 00:21:15.920
come in and given you their question. Absolutely so lazy

395
00:21:15.920 --> 00:21:21.079
of him. So we're talking about a binary brown dwarf

396
00:21:21.200 --> 00:21:24.119
system and will they collide?

397
00:21:24.240 --> 00:21:26.079
That was the first part of his question.

398
00:21:26.119 --> 00:21:28.680
So a few little parts to that, and the answer

399
00:21:28.759 --> 00:21:33.119
to that is almost certainly no. But and there's always

400
00:21:33.160 --> 00:21:35.839
a boot. So if you imagine initially that you have

401
00:21:35.920 --> 00:21:40.200
those two brown dwarfs orbiting one another, totally separate from

402
00:21:40.200 --> 00:21:42.599
the rest of the universe, so nothing else was interfering.

403
00:21:44.119 --> 00:21:47.519
Then the two will just continue orbiting as they are

404
00:21:47.640 --> 00:21:51.440
essentially forever, because you've got nothing to dissipair energy to

405
00:21:51.480 --> 00:21:52.440
slow them down to make.

406
00:21:52.359 --> 00:21:53.400
Them spiral inwards.

407
00:21:54.440 --> 00:21:57.480
Gets a bit more complicated though, in that there are

408
00:21:57.559 --> 00:22:00.279
things that can change the orbits to do with interaction. Now,

409
00:22:00.440 --> 00:22:02.559
these al tentric wife things to be close together. So

410
00:22:02.599 --> 00:22:05.440
if the brow dwarfs are really far apart, that's pretty

411
00:22:05.480 --> 00:22:07.160
much the end of the story. In less there's something

412
00:22:07.160 --> 00:22:10.720
else in the system whose gravity is perturbing them. But

413
00:22:10.799 --> 00:22:13.119
let's say you can bring the objects close enough together.

414
00:22:13.160 --> 00:22:15.319
And this isn't just a case for brand wolfs. Incidentally,

415
00:22:15.359 --> 00:22:18.759
it works for other things as well. If you have

416
00:22:18.880 --> 00:22:22.279
these objects rotating and they're close enough together, they can

417
00:22:22.359 --> 00:22:25.880
tidally interact with one another, and their orbits can change

418
00:22:26.119 --> 00:22:27.119
as a result of.

419
00:22:27.000 --> 00:22:28.039
That tidal interaction.

420
00:22:28.079 --> 00:22:30.559
And we've talked about this before with the fact that

421
00:22:30.599 --> 00:22:33.200
the Moon is moving away from the Earth. The Moon

422
00:22:33.240 --> 00:22:35.480
has one face pointed towards the Earth all the time,

423
00:22:35.480 --> 00:22:38.599
but the Earth is slowly spinning slower and slower, and

424
00:22:38.640 --> 00:22:40.720
the Moon is moving away as a result. So that's

425
00:22:41.079 --> 00:22:44.400
the tidal interaction between the two acting to change the

426
00:22:44.519 --> 00:22:47.400
orbit of the Moon. Now, because the Moon's orbital period

427
00:22:47.440 --> 00:22:49.480
is longer than the time it takes the Earth to rotate,

428
00:22:50.440 --> 00:22:53.400
that process is acting to cause the Moon to move

429
00:22:53.440 --> 00:22:55.960
away from the Earth, not towards us. But if you

430
00:22:56.000 --> 00:22:58.799
went to Mars, the innermost of Mars and Tu moons,

431
00:22:58.799 --> 00:23:02.200
which is Phobos, is closer to Mars than that cor

432
00:23:02.279 --> 00:23:05.599
rotation speed. So Phoebos orbits with an orbital period quicker

433
00:23:05.599 --> 00:23:09.279
than Mars's spin wred. So the tidal intraction between those

434
00:23:09.400 --> 00:23:11.960
is causing Phoebos to actually slow down in its orbit,

435
00:23:12.319 --> 00:23:14.480
for its orbit to get quicker and quicker and closer

436
00:23:14.480 --> 00:23:18.039
and closer, and will eventually cause Forebos to crash into Mars. Well,

437
00:23:18.039 --> 00:23:20.519
we'll probably break apart form a ring and bits of

438
00:23:20.559 --> 00:23:22.680
it will rain down on Mars in twenty to fifty

439
00:23:22.680 --> 00:23:26.240
million years in the future. And if I'm having a

440
00:23:26.240 --> 00:23:29.200
brain fart and it's actually Demus spiraling inwards, my apologies.

441
00:23:29.240 --> 00:23:30.960
But I think Phebos is the closer the two, and

442
00:23:30.960 --> 00:23:34.440
that's someone spiraling in So you can get these tidal

443
00:23:34.480 --> 00:23:37.960
interactions when you're close enough that can cause the orbit

444
00:23:38.039 --> 00:23:41.000
to change, but you'll only move inwards if the orbital

445
00:23:41.039 --> 00:23:45.039
period is shorter than the rotation period. If the orbital

446
00:23:45.079 --> 00:23:47.160
period is longer than the rotation period, you'll move the

447
00:23:47.160 --> 00:23:50.519
other way, and you'll move away. The final thing that

448
00:23:50.559 --> 00:23:54.680
can happen, well, another way it can happen is you

449
00:23:54.720 --> 00:23:58.319
see this for evolved stars. So if a star has

450
00:23:58.359 --> 00:24:00.880
a companion and the star gets to the end of

451
00:24:00.920 --> 00:24:02.880
its life and swells up to become a red giant,

452
00:24:03.559 --> 00:24:05.640
it can get bigger, and then the companion can be

453
00:24:05.680 --> 00:24:07.960
moving through the gas and the envelope of that other star,

454
00:24:08.000 --> 00:24:10.799
which provides a headwind, and that can cause its spiraling

455
00:24:10.839 --> 00:24:13.920
towards a close encounter as well. Now, sometimes that will

456
00:24:13.960 --> 00:24:15.880
just lead to one star numbing up another one and

457
00:24:16.279 --> 00:24:19.279
devouring it, and that's all good. But sometimes what that

458
00:24:19.400 --> 00:24:22.359
leaves you with is two evolved stars very close together,

459
00:24:22.400 --> 00:24:25.160
and that can be we see with binary neutron stars,

460
00:24:25.160 --> 00:24:28.440
binary white dwarfs, partnerships between black holes and neutron stars,

461
00:24:28.480 --> 00:24:31.480
all sorts. In recent years have been all these detection

462
00:24:31.559 --> 00:24:35.519
of gravitational waves from colliding stars, and they're all from

463
00:24:35.759 --> 00:24:38.359
black holes coliding with each other on neutron stars coliding

464
00:24:38.359 --> 00:24:41.279
with each other. And that's because those two black holes

465
00:24:41.319 --> 00:24:44.119
or the two neutron stars are very massive, but they're

466
00:24:44.160 --> 00:24:47.480
also very close together. So there are effects that are

467
00:24:47.519 --> 00:24:50.359
explained in general relativity and essentially make my head hurt.

468
00:24:51.079 --> 00:24:54.000
That cause a loss of energy from the binary as

469
00:24:54.000 --> 00:24:58.160
it radiates awhere gravitational waves. That causes the orbits to

470
00:24:58.200 --> 00:25:01.960
spiral inwards, so in they get the more pronounced this effected,

471
00:25:02.039 --> 00:25:04.960
so you get this runaway collapse of the two orbits

472
00:25:04.960 --> 00:25:06.240
and they end up hitting each other in.

473
00:25:06.200 --> 00:25:07.960
A big burst of gravitational waves.

474
00:25:08.759 --> 00:25:10.960
I think it's unlikely that'll apply to brown dwarfs, but

475
00:25:11.000 --> 00:25:14.079
that's another way they could spiral in so coming back

476
00:25:14.119 --> 00:25:17.039
out from that. In general, if they're quite far apart,

477
00:25:17.119 --> 00:25:19.480
there is no risk of them ever colliding. If they're

478
00:25:19.519 --> 00:25:22.680
really close together, it's possible. Now the final bit about

479
00:25:22.720 --> 00:25:25.200
could they turn into a star, It's all about the

480
00:25:25.240 --> 00:25:28.119
mass you get. If you have enough mass, then the

481
00:25:28.160 --> 00:25:30.359
temperature and pressure in the car will get in the

482
00:25:30.480 --> 00:25:33.359
core will get high enough for hydrogen fusion to start,

483
00:25:33.480 --> 00:25:36.119
hydrogen to turn to helium, and that's when it will

484
00:25:36.160 --> 00:25:39.000
really turn on as a star. Now, if you had

485
00:25:39.000 --> 00:25:41.519
two very massive brown dwarfs that are each not quite

486
00:25:41.519 --> 00:25:43.640
massive enough to be a star, and if you add

487
00:25:43.640 --> 00:25:46.119
them together, you'd suddenly be massive enough to be a star,

488
00:25:46.480 --> 00:25:49.440
and you might be able to cross that threshold. Now,

489
00:25:49.960 --> 00:25:52.079
we do see some examples of objects out there that

490
00:25:52.160 --> 00:25:54.960
are thought to probably be cases where two stars have

491
00:25:55.079 --> 00:25:58.000
merged and form a more massive star that looks out

492
00:25:58.039 --> 00:26:00.519
of place, and where this whole six in my mind

493
00:26:00.519 --> 00:26:04.799
of these objects called globular clusters, these massive spherical clusters

494
00:26:04.799 --> 00:26:08.279
of stars that are incredibly old. They're among the oldest

495
00:26:08.279 --> 00:26:11.559
things in the galaxy, and famous examples in our southern sky,

496
00:26:11.680 --> 00:26:14.680
things like Omega centauri forty seven Takhani, things like this.

497
00:26:15.319 --> 00:26:18.640
So you've got spherical bowler stars held together under gravity

498
00:26:19.000 --> 00:26:21.559
that is very old. And because sales clusters are very old,

499
00:26:21.920 --> 00:26:24.920
you don't expect them to have massive blue stars in them,

500
00:26:25.200 --> 00:26:27.759
because there's been no star formation recently in stars that

501
00:26:27.799 --> 00:26:31.000
are massive and blue live fast and die up, so

502
00:26:31.039 --> 00:26:33.240
they should be gone. But there's a small group of

503
00:26:33.279 --> 00:26:36.240
stars that have been identified called blue stragglers and the

504
00:26:36.319 --> 00:26:39.599
cold stragglers because should not be there. And for a

505
00:26:39.640 --> 00:26:41.599
long time there was puzzlement as to where these have

506
00:26:41.680 --> 00:26:44.559
come from, and I think there currently accepted wisdom is

507
00:26:44.599 --> 00:26:46.720
a blue straggler is what you get when you get

508
00:26:46.960 --> 00:26:50.240
two small or less massive and therefore longer lived stars

509
00:26:50.640 --> 00:26:53.200
that have merged, forming a more massive star that burns

510
00:26:53.200 --> 00:26:56.000
brighter and hotter. So you see what looks like a

511
00:26:56.039 --> 00:26:59.000
young hot star that is a product of two older

512
00:26:59.039 --> 00:27:03.160
cool stars merge. So you can't get things for us

513
00:27:03.200 --> 00:27:06.000
dollar sized off stella musk merging with one another to

514
00:27:06.160 --> 00:27:09.480
form a star, but it's unlikely to happen with any

515
00:27:09.519 --> 00:27:10.880
given set of brown dwarfs.

516
00:27:12.480 --> 00:27:16.799
Okay, yeah, I get it. Actually that all made perfect sense. Actually,

517
00:27:16.960 --> 00:27:19.519
I saw a story last or the other day about

518
00:27:19.519 --> 00:27:21.720
a young hot star that didn't win any Grammys.

519
00:27:21.799 --> 00:27:28.599
So rob even more hydrogen. Yes, yes, thank you know

520
00:27:28.640 --> 00:27:29.000
II Jill.

521
00:27:29.079 --> 00:27:35.480
Hopefully we covered everything with your brown dwarf analogy. Okay,

522
00:27:35.519 --> 00:27:41.839
we take a space nuts. Finally, a text question from Paddy.

523
00:27:41.920 --> 00:27:44.680
I am going to assume this is Paddy the roof Tyler,

524
00:27:44.680 --> 00:27:46.319
but it could be wrong. There could be more than

525
00:27:46.319 --> 00:27:49.400
one Paddy listening to us, especially if it's Ireland. I've

526
00:27:49.440 --> 00:27:52.359
got a feeling this this is the Australian version. Love

527
00:27:52.400 --> 00:27:52.680
the show.

528
00:27:52.799 --> 00:27:53.720
Keep up the great work.

529
00:27:54.160 --> 00:27:56.839
Since the episode on Mars quakes. I've been thinking about

530
00:27:56.880 --> 00:27:59.599
their origins. We know that the orbits of all the

531
00:27:59.599 --> 00:28:04.559
planets slowly expanding, meaning that they are moving away from

532
00:28:04.559 --> 00:28:08.480
the Sun and they're cooling. Now, given that a molderen

533
00:28:09.039 --> 00:28:13.640
rock cools crystal's form, and the slower cools, the larger

534
00:28:13.680 --> 00:28:16.359
the crystals, could it be possible that the internal structure

535
00:28:16.359 --> 00:28:20.400
of Mars is laced with veins of crystallizing rock that

536
00:28:20.519 --> 00:28:25.880
is fracturing, which is the instrument for the quakes. Shortly

537
00:28:25.920 --> 00:28:28.359
after the Mars quakes episode, there were reports of the

538
00:28:28.359 --> 00:28:31.880
possibility of water below the surface of Mars. This made

539
00:28:31.880 --> 00:28:34.559
me think that perhaps the quakes may be the result

540
00:28:34.640 --> 00:28:38.880
of liquid water freezing, thus expanding and fracturing the surrounding rock.

541
00:28:39.400 --> 00:28:42.359
This thought of the internal structure of Mars being fractured

542
00:28:42.440 --> 00:28:45.440
led me to the question of is it possible that

543
00:28:45.440 --> 00:28:48.240
Mars could break up? And if so, is it possible

544
00:28:48.480 --> 00:28:52.839
that this process could be the origin of the asteroid

545
00:28:52.880 --> 00:28:57.680
belt when another planet broke up as it's orbit drifted

546
00:28:57.759 --> 00:28:58.599
further away.

547
00:28:58.319 --> 00:28:58.880
From the Sun.

548
00:28:59.000 --> 00:29:03.200
Thank you both, and thank you to Hue Jeez Petty.

549
00:29:03.880 --> 00:29:07.440
He's been thinking a lot about this. I would suspect

550
00:29:07.839 --> 00:29:10.960
that Mars breaking up would not be likely.

551
00:29:10.759 --> 00:29:12.920
Due to gravity.

552
00:29:13.720 --> 00:29:16.440
Gravity wins for Mars. For this I figured that.

553
00:29:16.480 --> 00:29:21.160
But internal movement, you know, the cooling of the planet perhaps,

554
00:29:21.240 --> 00:29:23.640
or the expansion of frozen ice.

555
00:29:24.279 --> 00:29:25.240
Interesting series.

556
00:29:25.400 --> 00:29:27.480
There's a lot of interesting stuff to unpack here. So

557
00:29:28.599 --> 00:29:32.519
the effect of an object cooling causing some degree of

558
00:29:32.640 --> 00:29:36.559
quakes is actually fairly well established. I think now what

559
00:29:36.680 --> 00:29:38.759
needs to be remembered is that most things, when they.

560
00:29:38.680 --> 00:29:39.720
Cool actually contract.

561
00:29:40.119 --> 00:29:42.920
Water is really unusual. In the water ice that's near

562
00:29:43.039 --> 00:29:45.559
zere always bigger than the m volume of liquid water

563
00:29:45.960 --> 00:29:49.559
at the same temperature. For most materials, they're actually smaller

564
00:29:49.599 --> 00:29:52.319
the cooler they get. So what this has led to

565
00:29:53.079 --> 00:29:55.680
is on the Moon and on Mercury there are evidence

566
00:29:55.720 --> 00:29:59.039
of very unusual faulting structures which are thought to be

567
00:29:59.119 --> 00:30:02.839
the result of the interior cooling and shrinking. And then

568
00:30:02.880 --> 00:30:04.960
you get this cracking of the surface as the surface

569
00:30:05.039 --> 00:30:08.200
tries to drop essentially, and that of course leads to quakes.

570
00:30:08.200 --> 00:30:11.160
Now believe that quite a number of the quakes that

571
00:30:11.720 --> 00:30:13.440
are detected on the Moon and thought to have this

572
00:30:13.559 --> 00:30:16.799
kind of origin. You've then got the kind of freeze

573
00:30:17.039 --> 00:30:19.359
though processes that we're seeing, you know, growing up in

574
00:30:19.359 --> 00:30:21.759
the UK. The roads they get potholes far worse than

575
00:30:21.799 --> 00:30:24.559
we get here in Queensland, even though all the locals

576
00:30:24.559 --> 00:30:27.240
on the Facebook book groups keep complaining about the potholes there,

577
00:30:27.240 --> 00:30:29.599
which holes makes me laugh. The reason we get so

578
00:30:29.599 --> 00:30:32.559
many potholes up in the UK is because of freeze thaws.

579
00:30:32.640 --> 00:30:34.240
So if you get a very narrow crack and you

580
00:30:34.279 --> 00:30:37.960
get water in it, that water then freezers, it becomes

581
00:30:38.000 --> 00:30:40.640
ice and it expands, which is unusual. Like I said,

582
00:30:40.640 --> 00:30:43.400
water behaves oddly and that fractures the road, so you

583
00:30:43.400 --> 00:30:46.920
get this runaway fracturing of the surface. This on a

584
00:30:46.920 --> 00:30:50.400
different scale you also see in the degradation of rocks

585
00:30:50.400 --> 00:30:52.920
in places like the High Alcs, because as rocks heat

586
00:30:53.000 --> 00:30:56.319
up and cool down, they expand and contract and that

587
00:30:56.400 --> 00:30:59.960
leads to cracking and fracturing. This is an important process,

588
00:31:00.039 --> 00:31:03.599
particularly for my favorite metia shower, the Geminids. The geminids

589
00:31:03.599 --> 00:31:06.160
have a parent object that is Phyton, which often described

590
00:31:06.160 --> 00:31:10.079
as a rock comet, and Phyton has ridiculous temperature ranges

591
00:31:10.119 --> 00:31:11.799
through itself a bit. When it's nearest to sun, it's

592
00:31:11.799 --> 00:31:14.640
about seven hundred and fifty degrees. When it's furthest from

593
00:31:14.680 --> 00:31:16.880
the sunn it's one hundred degrees below freezing and more.

594
00:31:17.400 --> 00:31:19.599
And that's a huge range of temperatures over a couple

595
00:31:19.640 --> 00:31:23.200
of years. And one of the explanations for the Geminid

596
00:31:23.279 --> 00:31:26.880
Metia shower is that the rocks on Fifhon are persistently

597
00:31:26.920 --> 00:31:29.920
being crapped and fractured by this free saughtapp process by

598
00:31:29.920 --> 00:31:32.799
the heating and cooling, and then the dust gets kicked

599
00:31:32.799 --> 00:31:35.319
off the surface of the asteroid spreading out in space

600
00:31:35.359 --> 00:31:37.079
to give us a debris stream that we get for

601
00:31:37.160 --> 00:31:41.279
the Metia shower. So there is a lot to that there.

602
00:31:41.759 --> 00:31:45.039
In terms of the quakes on Mars, I think that

603
00:31:45.359 --> 00:31:47.400
a lot of them are being linked. We've got the

604
00:31:47.400 --> 00:31:49.880
ones that are linked to impacts, so asteroid hits Mars

605
00:31:49.880 --> 00:31:51.279
and Mars orins like a bell and you get a

606
00:31:51.319 --> 00:31:54.359
Mars quack. You then have ones that we talked about before,

607
00:31:54.359 --> 00:31:57.480
which are linked to that kind of residual tectonic energy

608
00:31:57.519 --> 00:32:00.559
and the heat movement within Mars. I think there have

609
00:32:00.599 --> 00:32:02.880
been situestions that some of them are probably also down

610
00:32:02.880 --> 00:32:05.079
to the cooling of the interior and that kind of

611
00:32:05.079 --> 00:32:07.880
cracking and faulting. So it is a process that would

612
00:32:07.920 --> 00:32:12.119
come into play there. However, it's probably not what caused

613
00:32:12.160 --> 00:32:15.599
the asteroid belt. So the asteroid belt is often portrayed

614
00:32:15.599 --> 00:32:18.000
in kind of science fiction as a planet that was destroyed,

615
00:32:18.440 --> 00:32:20.480
and it's probably fairer to describe it as a planet

616
00:32:20.519 --> 00:32:23.680
that never got to be. The total mass of the

617
00:32:23.720 --> 00:32:25.799
asteroid belt as we see it now is way less

618
00:32:25.799 --> 00:32:27.920
than the Moon, but it was more in the past.

619
00:32:28.599 --> 00:32:31.799
But Jupiter's the villain here. So when the planets were forming,

620
00:32:32.880 --> 00:32:35.160
Jupiter formed quicker because it's a little bit beyond what

621
00:32:35.160 --> 00:32:37.960
we call the snow line, so all the water that's

622
00:32:38.000 --> 00:32:39.680
out there, and as we said earlier in the podcast,

623
00:32:39.720 --> 00:32:42.480
water is one of the most common molecules in the universe.

624
00:32:43.119 --> 00:32:45.240
Jupiter was fair enough from the Sun that that water

625
00:32:45.359 --> 00:32:47.799
was ice, whereas in the inner Solar System it was gas.

626
00:32:48.160 --> 00:32:50.119
So suddenly, when you've got water ice, you've got a

627
00:32:50.119 --> 00:32:53.160
lot more solid material to build planets from. So Jupiter

628
00:32:53.200 --> 00:32:56.799
grew really quickly, and as it mass got bigger, its

629
00:32:56.799 --> 00:32:59.799
gravitational reach got more impactful, and it started stirring up

630
00:32:59.839 --> 00:33:04.160
the ashoid belt. That excitation meant that the average orbits

631
00:33:04.160 --> 00:33:06.599
of the asteroids were stirred up more, and so instead

632
00:33:06.599 --> 00:33:09.079
of the collisions between them being gentle enough to stick together,

633
00:33:09.119 --> 00:33:12.000
they entered a range where the collisions are destructive instead,

634
00:33:12.000 --> 00:33:15.880
they're colliding hard enough to smash apart. So Jupiter abridged

635
00:33:15.920 --> 00:33:18.759
the formation of a planet in that region by stirring

636
00:33:18.799 --> 00:33:20.720
things up so much that they couldn't collide and a

637
00:33:20.799 --> 00:33:24.039
crete anymore. So the asteroid belt isn't so much a

638
00:33:24.039 --> 00:33:26.920
planet that broke up as a planet that never got

639
00:33:26.960 --> 00:33:30.200
to form. And that's all thanks to Jupiter doing its

640
00:33:30.480 --> 00:33:34.000
thing and stirring everything up. So I think we've covered

641
00:33:34.000 --> 00:33:36.400
everything padi as there. I hope we've covered everything padi

642
00:33:36.400 --> 00:33:38.880
ass there. But yeah, there's a lot of good stuff

643
00:33:38.880 --> 00:33:39.200
in there.

644
00:33:39.680 --> 00:33:42.640
I might just add that some of the Earth some

645
00:33:42.720 --> 00:33:45.720
of the Mars quakes that have been detected are also

646
00:33:46.119 --> 00:33:48.119
being put down to media rite strikes.

647
00:33:48.279 --> 00:33:50.960
Yes, so they're the asteroids hitting it make it ring

648
00:33:51.079 --> 00:33:52.680
like a bell. And that was part of the reason

649
00:33:52.680 --> 00:33:54.720
we put the size montron Mars in the first place,

650
00:33:54.839 --> 00:33:56.039
was to detecting things.

651
00:33:56.440 --> 00:34:00.680
Yeah, okay, there you go, Thanks Peddy, great question. Good

652
00:34:00.759 --> 00:34:02.279
to hear from you, and don't forget. If you've got

653
00:34:02.279 --> 00:34:04.960
a question for us for our Q and A episodes,

654
00:34:05.000 --> 00:34:07.519
please go to our website and send them in. It's

655
00:34:07.559 --> 00:34:10.800
as simple as going to space Nuts podcast dot com

656
00:34:11.119 --> 00:34:13.920
and clicking on the little ama thing at the top.

657
00:34:14.599 --> 00:34:16.760
And if you want to send us a text question,

658
00:34:16.840 --> 00:34:18.639
you can do that, or you can send us an

659
00:34:18.719 --> 00:34:21.079
audio question. If you've got a device with a microphone,

660
00:34:21.119 --> 00:34:23.480
that's all you need. And don't forget to tell us

661
00:34:23.480 --> 00:34:26.280
who you are and where you're from. Johnty, thank you

662
00:34:26.320 --> 00:34:28.840
so much for answering all of those questions. I'm going

663
00:34:28.880 --> 00:34:30.239
to make you do it again next week.

664
00:34:30.599 --> 00:34:33.119
Solward's pleasure. It's good fun. Thank you for having me.

665
00:34:33.760 --> 00:34:37.440
Thank you, Johnny, Professor John T. Horner from the University

666
00:34:37.480 --> 00:34:41.119
of Southern Queensland. And look, Hugh in the studio was

667
00:34:41.119 --> 00:34:43.440
a no show again today. Now a lot of people

668
00:34:43.920 --> 00:34:47.960
ask us if Hugh is real. I'm starting to think

669
00:34:48.000 --> 00:34:52.440
you might be right that he doesn't exist. And from

670
00:34:52.519 --> 00:34:54.760
me Andrew Dunkley, thanks to your company. Catch you on

671
00:34:54.800 --> 00:34:57.119
the very next episode of Space Nuts.

672
00:34:57.280 --> 00:34:58.800
Bye bye, Thank Nuts.

673
00:34:59.119 --> 00:35:02.400
You'll be this to the Space Nuts podcast.

674
00:35:03.440 --> 00:35:09.480
Available at Apple Podcasts, Spotify, iHeartRadio, or your favorite podcast player.

675
00:35:09.639 --> 00:35:12.960
You can also stream on demand at bytes dot com.

676
00:35:13.000 --> 00:35:16.719
This has been another quality podcast production from nights dot

677
00:35:16.719 --> 00:35:18.639
com
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