Dec. 13, 2024

Ryugu Revelations, Martian Moon Theories & Galactic Shockwaves: #477

Space Nuts Episode: Ryugu's Microbial Mystery, Martian Moon Origins, and Galactic Collisions
Join Andrew Dunkley and Professor Fred Watson as they explore the latest cosmic revelations. From unexpected microbial contamination of Richie asteroid...

Show Notes
Transcript

Space Nuts Episode: Ryugu's Microbial Mystery, Martian Moon Origins, and Galactic Collisions
Join Andrew Dunkley and Professor Fred Watson as they explore the latest cosmic revelations. From unexpected microbial contamination of Richie asteroid samples to a groundbreaking theory on the formation of Mars's moons, and the first results from a new instrument on the William Herschel Telescope, this episode is packed with stellar insights and astronomical wonders.
Episode Highlights:
- Richie Asteroid Contamination: Delve into the challenges of keeping extraterrestrial samples free from Earth's microbes. Despite stringent sterilisation efforts, Richie samples returned by Hayabusa2 show signs of terrestrial contamination, raising questions about planetary protection protocols.
- Martian Moons' New Origin Theory: Discover a fresh perspective on how Phobos and Deimos may have formed. A new model suggests that these moons originated from debris of an asteroid that broke apart due to Mars's gravitational forces, offering an alternative to previous impact and capture theories.
- Galactic Collisions Unveiled: Explore the first findings from the WEAVE instrument on the William Herschel Telescope. By studying Stefan's Quintet, astronomers reveal the staggering speeds of shock waves from colliding galaxies, shedding light on cosmic interactions and future Milky Way-Andromeda collision scenarios.
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, Tumblr, Instagram, and TikTok. We love engaging with our community, so be sure to drop us a message or comment on your favourite platform.
For more Space and Astronomy News Podcasts, visit our HQ at www.bitesz.com.
Become a supporter of this podcast for extended commercial-free episodes and more. Visit our Support page for options: 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 - Andrew Dunkley: Coming up on this edition of Space Nuts
01:15 - This episode will be officially released two days after your 800th birthday
02:29 - Justin Jackson says Ryugu samples show effort to keep them clean has failed
12:12 - If that can happen in a room that's designed not to allow it
12:47 - New theory put forward about origin of moon's phobos and Deimos
21:22 - Andrew Dunkley says spherical potatoes could be useful in space missions
22:46 - Fred looks at an instrument connected to the William Herschel telescope
26:45 - Professor Gavin Dalton has been working on the William Herschel Telescope
31:30 - We've got similar collision speeds as Andromeda.
✍️ Episode References
Imperial College London
[imperial.ac.uk](https://www.imperial.ac.uk/)
Meteoritics and Planetary Science Journal
[wiley.com](https://onlinelibrary.wiley.com/journal/19455100)
phys.org
[phys.org](https://phys.org/)
Durham University
[durham.ac.uk](https://www.dur.ac.uk/)
NASA Spaceflight
[nasaspaceflight.com](https://www.nasaspaceflight.com/)
JAXA (Japanese Aerospace Exploration Agency)
[jaxa.jp](https://www.jaxa.jp/)
William Herschel Telescope
[ing.iac.es](http://www.ing.iac.es/astronomy/telescopes/wht/)
Isaac Newton Group of Telescopes
[ing.iac.es](http://www.ing.iac.es/)

Become a supporter of this podcast:

WEBVTT

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Hi there, Andrew Dunkley here. Thanks for joining us on

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another edition of Space Nuts.

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Coming up.

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This time, we are going to once again talk about

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the Riugu asteroid. We've had a couple of discussions about

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it recently, but the news this time is not so

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positive and it involves some kind of contamination that seems

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to have happened despite everyone's best efforts to avoid it.

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There's also a new theory that's been put forward thanks

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to computer modeling, about how the moons of Mars may

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well have formed. There's a few theories. This is a

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new one to add to the sphere boom boom, and

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the first results from a new instrument on the William

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Herschel Telescope. We'll talk about all of that on this

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edition of Space Nuts fifteen, Channel.

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Ten nine Ignition Space Nuts or three two one spaces

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Can I record it?

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Neil's good and joining me to talk about all of

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that and much much more is Professor Fred What's an

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astronomer at last? Tello Fred?

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Hello, Andrew, good to see you.

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Good to see you too. Now, before we start, I'm

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going to put you on the spot because I've been

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I've been looking at the calendar and working a few

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things out. This episode will be officially re released on

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the twelfth of the twelfth, and your birthday is two

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days later and you're turning eight hundred. Now, hang on,

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it's got an eight in it.

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Yeah, it begins with an E and it's not eleven.

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So that's a clue.

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So I suppose this episode we should start by collectively

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wishing you a very happy birthday, FREDI thank you, thanks

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e very much. Should it be two days time? Through

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relief of this episode, even though we're recording this one

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in twenty twenty one, so.

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Speaking for yourself, I thought it was in nineteen forty seven.

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Yeah, it could have been toned. No, No, we were

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running a bit early to see out the year. But

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I hope you have a wonderful birthday, Fred, and now

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you've got many, many more. Yeah, that's the important bear,

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That is the important bit.

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Yes, that's right.

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Got to keep this thing that the brain cells ticking over.

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I think that's the secret.

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To long life.

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Just I think space heats of brain whewing space notes.

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Yes, absolutely.

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Now we have got some fascinating stories today, and we'll

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start off with Rugu, the asteroid that was visited a

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Japanese mission. I believe that brought back samples and they've

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been looking at those samples, and now they've looked at

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them and gone, ha, hang on a minute, what's happened here?

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Somebody spilled some jam on them or something that wasn't that,

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But they do appear to have become questionable in terms

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of the quality because the effort to keep them clean

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has failed.

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That's right, And that's really the lesson of this story,

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just how hard it is to keep earthly microbes away

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from anything. And you know, it has implications with our

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sterilization processes for spacecraft going to other worlds. We've talked

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before about the Planetary Protection Rules, which mean that if

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you're sending a spacecraft to somewhere on Mars where liquid

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water could exist, it's got to have the very highest

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if I remember, its Category four C sterilization, which means

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that there are only thirty microbes on board the spacecraft.

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I don't know how they do that, but that's what

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they do. But what this story is telling us is

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that that might not be enough. That might just you know,

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be effectively scratching the surface. And so this is some

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work that's been done at Imperial College in London, one

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of the London universities, and a paper that's been published

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in Meteoritics and Planetary Science, which is called rapid Colonization

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of a space returned UGU sample by terrestrial microorganisms, And

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basically it tells you that on the surface of the

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samples that came back to Earth from this via the

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Hyabusa two spacecraft from Rugu, they have found microbes, basically,

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and it's extraordinary that, you know, the the despite everybody's

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best efforts to keep these free from contaminations, they've got contaminated.

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I might just read a very nice article on fizz

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dot org which is just It is one of by

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Justin Jackson, and there's a paragraph here that tells you what,

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basically what the samples underwent to keep them clean. So

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that transported to Earth in a hermetically sealed chamber. The

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sample was opened in nitrogen in a Class ten thousand

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clean room. I don't know what that means, but it

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sounds very clean. To prevent contamination, individual particles were picked

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with sterilized tools and stored under nitrogen in air type

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containers before analysis. The sample underwent nano X ray computed

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tomography and was embedded in an epoxy resin block for

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scanning electro scanning electron microscopy. But this found these what

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are described as rods and filaments of organic matter and

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a lovely lovely phrase here interpreted as filamentous microorganisms were

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observed on the sample surface and yeah, variations in size

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and morphology or shape of these structures resembled known terrestrial microbes,

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and observations showed that the abundance of these filaments changed

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over time, suggesting on growth and decline of a population.

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It's incredible, isn't it That no matter what you do,

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you can't keep them clean. And so it's it's really

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a lesson, I think for our future understanding of the

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exploration of life beyond the Earth. For a start, it

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means that there's probably microbial contamination now on Mars, on

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the Moon, it's all over the place.

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If we've created a really significant clean environment for those

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samples we've brought back, it stands to reason we've sent

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microbes to other worlds because we probably weren't that thorough

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in sending those spacecraft, and if the safety situation was

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so strict on the Ryugu samples and the microbes got through.

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It stands to reason that we have sent micrabs all

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over the system.

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Pretty well.

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Yeah, it's a bit scary really because if there is

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a world with life and we've sent microbes to them,

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what could happen? I mean, my logic says to may

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our microbes wouldn't survive, but they're pretty.

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Tough, and more than that, they adapt. There's another lovely

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paragraph from Justin's Peace on fiz dot org which is

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basically what we've just been saying. NASA tries to avoid

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introducing earth microbes to Mars by constructing probes and landers

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in clean room environments, and has found the task nearly impossible.

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There have been species of microbes Wait for this, there

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have been species of microbes discovered in NASA clean rooms

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that not only evade disinfection methods, but also adapt to

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using cleaning agents as a food source.

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Yes, I know. That's absolutely blew in my mind when

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I read that.

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Good grief.

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Yeah, so, I mean that that is the a glaring

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example of adaptation to an environment, isn't it. When that's right,

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let's eat the petrol?

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Yes exactly, Yeah, that's basically do it incredible, that's quite natural.

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I know, I know that somebody in our audience, probably

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more than one person, will say, hang on a minute,

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how do we know that these weren't microbes that already

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existed on reug And they're pretty they're pretty positive that

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they aren't. The article says, population statistics indicate that the

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microorgans microorganisms originated from terrestrial contamination during the sample preparation stage,

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rather than being indigenous to the asteroid. So yeah, they

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are very confident and probably disappointed that they are not.

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Yeah, that's right, asteroidal origin.

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Yeah, I mean, people do look for signs of perhaps

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fossilized microbes in meteorites, particularly and you'll remember it's ALH

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eight four zero zero zero one, I think was the

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name of it, the Allen Hills meteorites, which in the

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early nineteen nineties was found to have within its structure

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these weren't on the surface like these things that have

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been found in this story, but within its structure it

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was found to have things that strongly resemble terrestrial microbes,

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only they were about a thousand times smaller. So the

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court started calling them nanobes because you know, they were

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on a nanoscale rather than microscope. But it turned out

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that there are simple chemical reactions that take place in

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geological formations that can produce these things that look like

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if that look like living organisms. So the astrobiology community

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has been pretty strict about what the criteria are for

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having discovered life in a meteorite. And it's not just

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that you find something that looks like a microbe. I

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think there are chemical tests and things of that sort

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that will be done that would, you know, verify if

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this was indeed a microbe that had come from Mars.

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But I think, you know, it's still possible we might

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find something like that. I think there's so much activity

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in this field Andrew that I think there's a good

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chance we might one day turn up a Martian microbe.

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And even more likely that when finally the soil and

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rock samples from Persevereherance come back to Earth, that we

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might find something in there that's that will be the

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that will be the really exciting story when when that's

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an EASA get their act together. I don't know what

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the situation is, but I think it's still in abeyance

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because everything that the planned was going to cost too much.

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But to bring back these little tubes of Martian soil

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and rock that have been left by perseverance on the

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surface of Mars.

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Yeah. That's so human, isn't it. Let's get some samples. Yeah,

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but what are we going to do about collecting them?

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Oh yeah, we'll figure that out. We'll figure it out later. Oh,

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hang on, it's going to cost too much. Oh, we'll

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figure it out much later.

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Well that's basically where we are now. Yeah, less that's

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in there. Give other mens that I'm not aware of. Yes,

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it's a very human thing. She'll be right.

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But I do agree with you that sometime in they're

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not too distant future, we will find evidence of past

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life somewhere in the Solar system. And this is a

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classic example of how life can grasp even the smallest,

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almost impossible opportunity. And if that can if that can

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happen in a room that's designed not to allow it

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to happen, then it could probably happen anywhere exactly. And

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you don't even have to add the caveat if the

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circumstances are right, because the circumstances were not right and

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it still happened.

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Yeah, that's really quite extraordinary.

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Yeah, amazing story, And you can read it at fizz

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dot org. You're listening to Space Nuts with Andrew Dunkley

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and Professor Fred.

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Watson Space Nuts. Now this next.

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Story takes us to Mars, and there's a new theory

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that's been put forward about the origin of the Moon's

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Phobos and de Moss. There were I think there were

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two theories that previously existed, and that was that they

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are both captured asteroids. I think the other theory was

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that something hit Mars just like fear hit Earth and

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created the moons as a consequence of that impact. Now

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they've got another idea, and this one seems to have

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just as much validity, maybe more.

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Yes, that's right. In fact, it's the modeling really seems

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to demonstrate that this is on the right track. It's

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a study that's been carried out by scientists in the

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United States as well as well as using some code

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that Durham University has prepared. That's the University of Durham

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in the UK. They've got one of the most advanced

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computing systems in the United Kingdom and they've used it

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to build models of the universe that are kind of

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complete in every detail. It's amazing stuff. So that computing

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facility has been used in this research trying to work

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00:14:07.360 --> 00:14:11.799
out what happened happened to create these two tiny moons

217
00:14:12.360 --> 00:14:15.360
of Mars, Phobos, which if I remember rightly, is about

218
00:14:15.720 --> 00:14:19.559
twenty three kilometers across, shaped like a potato, and Demos,

219
00:14:19.559 --> 00:14:21.679
which is quite a bit smaller. I think it's only

220
00:14:21.759 --> 00:14:26.159
fifteen or thereabouts kilometers across and shaped a bit like

221
00:14:26.240 --> 00:14:33.960
a smaller potato. So you're quite right. Two theories. One

222
00:14:34.080 --> 00:14:36.519
is that there were simply asteroids that were captured when

223
00:14:36.519 --> 00:14:39.320
they passed close to Mars, and the other one is

224
00:14:39.399 --> 00:14:44.639
that perhaps there was a giant impact is exactly as

225
00:14:44.679 --> 00:14:47.000
you've said, a little bit like thea impacting the Earth

226
00:14:47.000 --> 00:14:50.000
and creating the Moon, an impact on the Martian surface

227
00:14:50.000 --> 00:14:53.320
that lifted an enormous amount of material to form a

228
00:14:53.320 --> 00:14:56.600
disc of material around Mars, and the moons are basically

229
00:14:56.639 --> 00:15:01.840
formed in that disc. And that's probably the more popular theory.

230
00:15:03.080 --> 00:15:05.960
But uh, and the reason for that is that it

231
00:15:06.879 --> 00:15:11.120
really neatly accounts for the orbits of Phobos and Demons.

232
00:15:11.159 --> 00:15:15.000
That's why people like that because it sort of matches

233
00:15:15.039 --> 00:15:17.440
the present day orbits of Phobos and demas. That's what

234
00:15:17.519 --> 00:15:22.879
you get if this ejector from an impact had collected

235
00:15:23.480 --> 00:15:30.000
in orbit around Mars. But there is a snag, and

236
00:15:30.120 --> 00:15:35.320
one is that if that had been the case, if

237
00:15:35.559 --> 00:15:39.519
if these worlds are made of material that was ejected

238
00:15:39.519 --> 00:15:44.679
from Mars itself, they would have formed closer to Mars

239
00:15:44.720 --> 00:15:50.320
than they are. Uh. And the there's a gotcha in

240
00:15:50.360 --> 00:15:55.759
particular with Demos. It's the radius of its orbits tells

241
00:15:55.799 --> 00:15:58.639
you that it actually had to form that far away

242
00:15:58.759 --> 00:16:02.200
from Mars. It couldn't have formed very close to Mars

243
00:16:02.320 --> 00:16:05.679
and then migrated outwards. It would have basically just gone

244
00:16:05.720 --> 00:16:11.440
back to Mars and crashed again. And so this new material, sorry,

245
00:16:11.480 --> 00:16:17.360
this new model suggests that the material from which these

246
00:16:17.399 --> 00:16:21.240
two worlds are made, Fobos and Demos, didn't come from Mars.

247
00:16:21.679 --> 00:16:24.960
That it came from an asteroid that passed too close

248
00:16:25.000 --> 00:16:31.759
to Mars's surface and basically broke up as it bypassed Mars.

249
00:16:32.679 --> 00:16:37.840
So if you imagine an asteroid heading in Mars's direction,

250
00:16:37.960 --> 00:16:41.159
it's not going to impact the planet, but it's going

251
00:16:41.240 --> 00:16:44.120
to do a near miss. Now, a near miss means

252
00:16:44.159 --> 00:16:47.120
that it's very close to Mars's surface and it feels

253
00:16:47.360 --> 00:16:50.200
very strong tidal effect. And what we mean by tidal

254
00:16:50.200 --> 00:16:55.200
effect is the difference in the gravitational pull on one

255
00:16:55.240 --> 00:16:58.080
side of an object compared with the other. That's what

256
00:16:58.159 --> 00:17:02.759
quit creates tides on Earth. The near side of this

257
00:17:03.000 --> 00:17:06.559
asteroid hypothetical asteroid would have felt more gravity than the

258
00:17:06.559 --> 00:17:09.920
far side, and that creates tension within it, which basically

259
00:17:09.920 --> 00:17:13.599
breaks it up. So this thing you cannot withstand the

260
00:17:13.599 --> 00:17:18.599
tidal forces. It breaks up into debris and then circulates

261
00:17:18.839 --> 00:17:25.759
around Mars, and eventually Phobos and Demos are formed within

262
00:17:25.839 --> 00:17:33.279
that ring of material. And in fact, it's very nicely

263
00:17:33.480 --> 00:17:37.200
accounts for the differences between Phobos and Demos and the

264
00:17:37.240 --> 00:17:39.240
different orbits that they've got.

265
00:17:40.440 --> 00:17:46.920
Okay, well, so it's not dissimilar to theory too that

266
00:17:47.000 --> 00:17:49.079
what they're saying. To expand on what you were saying,

267
00:17:50.640 --> 00:17:54.079
it's an asteroid that was passing Mars. The gravitational effect

268
00:17:54.160 --> 00:17:58.799
caused it to break up. But further too that all

269
00:17:58.839 --> 00:18:02.880
those bits and pieces continued to collide and smash up

270
00:18:02.920 --> 00:18:07.440
and created created a proto planetary disc if you like,

271
00:18:09.160 --> 00:18:12.640
on on Mars scale, and then that formed into the

272
00:18:12.680 --> 00:18:15.119
two moons. Is that what they that's what they're saying.

273
00:18:15.400 --> 00:18:18.880
That's that's correct. Yes, that's what they're saying. And the

274
00:18:18.920 --> 00:18:23.759
model sort of makes predictions about the the orbits of

275
00:18:23.799 --> 00:18:27.319
the final orbits of the Moon, which which basically are

276
00:18:27.559 --> 00:18:31.359
what we see in reality. So yes, it's it's it's

277
00:18:31.680 --> 00:18:34.799
a very nice piece of work, and there is some

278
00:18:35.599 --> 00:18:41.279
possibility that we might get some hard and fast results

279
00:18:41.279 --> 00:18:45.359
from both Phobos and Demos because there's a JAXA spacecraft

280
00:18:45.480 --> 00:18:52.079
Japanese Aerospace Exploration Agency called MMX, which is the Martian

281
00:18:52.200 --> 00:18:57.480
Moon's Explorer or Martian Moon's Exploration mission, and it's a

282
00:18:57.519 --> 00:19:01.240
simple return mission, and the Japanese are very good at

283
00:19:01.319 --> 00:19:04.039
sample return. We've just been talking about the fragments of

284
00:19:04.079 --> 00:19:06.839
asteroid Ryugu, which is a sample return from an asteroid.

285
00:19:07.599 --> 00:19:12.440
So this mission will will bring back samples from both

286
00:19:12.519 --> 00:19:16.400
Phobos and Demos and give us a lot more close

287
00:19:16.480 --> 00:19:18.839
up studies of those two worlds. And so you know,

288
00:19:18.920 --> 00:19:23.160
we might find from whatever they bring back that we

289
00:19:23.720 --> 00:19:28.039
find the compositions of the Moons actually would match what

290
00:19:29.680 --> 00:19:35.519
this scenario suggests, because you'd expect if it was a

291
00:19:35.559 --> 00:19:40.400
broken up asteroid, you'd expect the material, the isotopic content

292
00:19:40.440 --> 00:19:42.839
of the material of which Phobos and Demos were made

293
00:19:43.119 --> 00:19:45.920
would match that of the asteroid rather than Mars itself,

294
00:19:46.920 --> 00:19:49.680
which is what you get from a collision. So MMX

295
00:19:50.079 --> 00:19:53.559
launch in twenty twenty six and something I hope we'll

296
00:19:53.599 --> 00:19:56.440
talk about on the space nuts.

297
00:19:57.519 --> 00:20:03.559
Absolutely one question though, if that was the case, and

298
00:20:05.480 --> 00:20:08.400
you can write off theory one, which was like, you know,

299
00:20:08.480 --> 00:20:12.880
Mars just captured two passing asteroids, Theory two and theory

300
00:20:13.000 --> 00:20:19.559
three still see ejecta or material being used to form

301
00:20:19.599 --> 00:20:23.240
the moons, why wouldn't they be spherical?

302
00:20:23.759 --> 00:20:26.519
If that's the case, I'm being answer.

303
00:20:26.279 --> 00:20:27.920
For the gravity you can create them.

304
00:20:28.160 --> 00:20:30.960
Yes, that's correct, that's absolutely it. So that you know,

305
00:20:31.000 --> 00:20:34.839
it's like a lot of asteroids are mobbly shaped, they're

306
00:20:34.839 --> 00:20:37.279
a bit like some of them are very like spinning tops,

307
00:20:37.319 --> 00:20:40.759
they're the rubble piles. Some of them are like potatoes,

308
00:20:40.799 --> 00:20:43.599
some are like dumbbells. And that's probably two asteroids that

309
00:20:43.599 --> 00:20:47.200
have come together, and you know that originally in orbit

310
00:20:47.240 --> 00:20:50.559
around each other and have now become one. So so

311
00:20:51.200 --> 00:20:56.079
on a sample return would I think allow a distinction

312
00:20:56.240 --> 00:20:59.400
between all of those models, so we might have a

313
00:20:59.480 --> 00:21:03.200
very good in much the same way as a sample

314
00:21:03.240 --> 00:21:05.240
returns from the moon back in the nineteen sixties and

315
00:21:05.319 --> 00:21:08.680
seventies gave us our ideas for how the moon formed.

316
00:21:10.559 --> 00:21:12.960
Okay, yeah, you know what we've learned from this from

317
00:21:13.000 --> 00:21:17.880
a horticultural perspective thread, If potatoes on Earth grew bigger,

318
00:21:17.920 --> 00:21:21.359
they ultimately become spherical, that's what we've learned from.

319
00:21:21.000 --> 00:21:25.319
They would, they absolutely would, Yes, that's fairical potato. But

320
00:21:25.319 --> 00:21:28.000
they'd have to be big enough for their own gravity

321
00:21:28.039 --> 00:21:30.160
to pull them into auspherical shape while they were in

322
00:21:30.200 --> 00:21:31.960
free for so you need to be throwing them up

323
00:21:31.960 --> 00:21:34.359
in the air as well as as well as let

324
00:21:34.359 --> 00:21:35.200
them grow bigger.

325
00:21:36.400 --> 00:21:37.720
That would just add to the price.

326
00:21:38.440 --> 00:21:41.960
Yeah, they'd have to get up to in the region

327
00:21:41.960 --> 00:21:46.000
of five hundred kilometers in diameter, and most potatoes are not. Actually,

328
00:21:46.920 --> 00:21:50.559
you know, you see these prize winning marrows and pump

329
00:21:50.640 --> 00:21:52.839
kits and things like that that people need a wheelbarrow

330
00:21:52.920 --> 00:21:56.319
to move around for forget it. Very cool potato.

331
00:21:57.079 --> 00:22:01.880
It's an interesting hobby that and I yeah, and I

332
00:22:01.960 --> 00:22:04.440
just don't understand the logic of growing giant fruit that

333
00:22:04.480 --> 00:22:08.079
nobody can eat, or giant no vegetables.

334
00:22:08.839 --> 00:22:11.519
So you know, you can turn them into motorway crash

335
00:22:11.599 --> 00:22:13.680
barriers and things like that. They're quite useful and that

336
00:22:13.920 --> 00:22:15.960
we can't but yes you.

337
00:22:15.960 --> 00:22:19.599
Can, oh, gosh. But yeah, it's a really interesting theory

338
00:22:19.640 --> 00:22:24.119
and it probably holds water compared to the other two

339
00:22:25.559 --> 00:22:30.440
theory two theory three both the same in result, different

340
00:22:30.640 --> 00:22:35.480
different techniques. Yeah, but you can read that story at

341
00:22:35.559 --> 00:22:39.559
NASA Spaceflight dot Com. There's a space that it's Andrew

342
00:22:39.599 --> 00:22:41.240
Dunkley here with professor.

343
00:22:40.880 --> 00:22:48.640
Fred space MutS our final story.

344
00:22:48.759 --> 00:22:51.200
Fred looks at an instrument. It's not a violin, the

345
00:22:51.319 --> 00:22:55.359
cello or a saxophone. It is an instrument connected to

346
00:22:55.400 --> 00:22:59.920
the William Herschel telescope and it's just come up with

347
00:23:00.160 --> 00:23:04.039
some really interesting information about colliding galaxies.

348
00:23:04.880 --> 00:23:09.279
Do tell Yeah, So just about the instrument itself, which

349
00:23:10.039 --> 00:23:13.319
is something built by very close colleagues of mine actually

350
00:23:13.359 --> 00:23:18.000
at the University of Oxford in the United Kingdom, and

351
00:23:18.240 --> 00:23:21.960
it's a little bit like we have, for think, called

352
00:23:22.000 --> 00:23:24.880
two DF on the Angle Australian Telescope. Tow DF stands

353
00:23:24.880 --> 00:23:27.359
for the two degree field and it's a device that

354
00:23:27.480 --> 00:23:30.799
lets you position optical fibers and in fact, in two

355
00:23:30.839 --> 00:23:34.720
DF there are four hundred of them in exact alignment

356
00:23:35.000 --> 00:23:38.160
with the images that the telescope delivers, so you can,

357
00:23:38.240 --> 00:23:41.680
for example, measure the characteristics of four hundred stars at

358
00:23:41.720 --> 00:23:43.839
a time, or four hundred galaxies at a time. And

359
00:23:44.160 --> 00:23:46.160
you know, back in the day when I started my career,

360
00:23:46.400 --> 00:23:49.480
you could only observe the spectra, the rainbow spectra with

361
00:23:49.519 --> 00:23:52.000
all its information locked up in it. You can only

362
00:23:52.039 --> 00:23:55.039
do that one at a time at least to get

363
00:23:55.039 --> 00:23:55.759
the details.

364
00:23:56.279 --> 00:23:58.960
No, you and I, You and I did it a

365
00:23:58.960 --> 00:24:03.960
little TV special about the two DF when it was installbleent. Yeah, yep, yep,

366
00:24:04.119 --> 00:24:05.119
I remember then.

367
00:24:05.160 --> 00:24:09.119
That's right. So two DF has been incredibly successful. Now,

368
00:24:09.160 --> 00:24:12.559
the William Herschel Telescope which was built if I remember rightly,

369
00:24:12.599 --> 00:24:15.480
it was commissioned in nineteen eighty seven. It's a telescope

370
00:24:15.519 --> 00:24:18.640
of a similar size to our Anglo Australian telescope. It's

371
00:24:18.680 --> 00:24:21.000
got a slightly bigger mirror. It's four point two meters

372
00:24:21.440 --> 00:24:23.519
it was against three point nine meters. But it was

373
00:24:23.559 --> 00:24:26.079
built by the same company, so Howard grub Parsons with

374
00:24:26.160 --> 00:24:31.240
whom I started my career, Andrew and so the William

375
00:24:31.240 --> 00:24:34.640
Herschel telescope is not in Australia though, like ours is.

376
00:24:35.359 --> 00:24:37.759
It's on the island of La Palma, which is one

377
00:24:37.759 --> 00:24:41.359
of the Canary Islands in off the West coast of

378
00:24:41.519 --> 00:24:46.920
Africa and La Palma is basically a giant volcanic cone.

379
00:24:47.400 --> 00:24:49.480
In fact, it has an active volcano in the south

380
00:24:49.519 --> 00:24:51.240
of the island, which has been in the newest within

381
00:24:51.279 --> 00:24:52.359
the last couple of years.

382
00:24:52.440 --> 00:24:56.039
I think Judy and I will be visiting there next year.

383
00:24:56.400 --> 00:24:58.880
Oh well, I had to check out.

384
00:24:58.759 --> 00:25:00.720
Our itinery, but I've got a fe we do make

385
00:25:00.759 --> 00:25:02.720
a stop at the Canary Islands.

386
00:25:03.079 --> 00:25:06.519
Yeah, well, if you There are quite a few Canary islands,

387
00:25:06.680 --> 00:25:10.519
but La Palma is certainly the interesting one from from

388
00:25:10.920 --> 00:25:14.240
an astronomical point of view, as is Tenerifa, the bigger

389
00:25:14.279 --> 00:25:17.039
island not very far away that's got telescope on its

390
00:25:17.319 --> 00:25:21.759
On its summit a mountain called Cadi. The mountain on

391
00:25:22.480 --> 00:25:28.920
La Palma is a rocket de Delsarchos, which means the

392
00:25:29.039 --> 00:25:30.960
rock of the Brothers or the rock of the Friends.

393
00:25:31.400 --> 00:25:34.799
It's a sort of strange rock formation on top of

394
00:25:34.839 --> 00:25:37.880
the mountain, but that's where the telescopes are, including the

395
00:25:37.880 --> 00:25:40.279
William Herschel telescope, which for a while was the biggest

396
00:25:40.880 --> 00:25:43.160

Ryugu Revelations, Martian Moon Theories & Galactic Shockwaves: #477

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Ryugu Revelations, Martian Moon Theories & Galactic Shockwaves: #477

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