S27E115: Black Hole Star Feasts, Earth's Mantle Mystery, and Lunar Water Abundance

[00:00:00] [SPEAKER_02]: This is SpaceTime's series 27, episode 115 for broadcast on the 23rd of September 2024. Coming up on SpaceTime, how Black Hole's 8 Stars?

[00:00:12] [SPEAKER_02]: New revelations about the Earth's mantle, and it seems water is far more widespread on the moon than previously thought.

[00:00:20] [SPEAKER_02]: All that and more coming up on SpaceTime.

[00:00:25] [SPEAKER_00]: Welcome to SpaceTime with Stuart Gary

[00:00:44] [SPEAKER_02]: Astronomers have developed a new computer simulation detailing how monstrous Black holes at the centers of galaxies can physically rip apart and consume an entire star.

[00:00:55] [SPEAKER_02]: The new research reported in the Astro-Physical Journal letters captures this complex process in great detail,

[00:01:02] [SPEAKER_02]: also providing new insights into the mysterious optical and ultraviolet emissions, observing these catastrophic events.

[00:01:08] [SPEAKER_02]: The state is lead author Daniel Price from my National University, since the program represents the first self-consistent simulation of the star being tidally disrupted by a supermassive Black Hole, followed by the evolution of the resulting debris over the course of a year.

[00:01:24] [SPEAKER_02]: When a star passes too close to a supermassive Black Hole, the intense gravitational forces of the Black Hole tear the star apart in a process called a tidal disruption event,

[00:01:36] [SPEAKER_02]: that debris from the unfortunate star then forms a stream of material which will eventually feed into the Black Hole.

[00:01:43] [SPEAKER_02]: But this material doesn't dissipate on the Black Hole all at once.

[00:01:47] [SPEAKER_02]: First, it creates a swirling accretion disk around the Black Hole, and as the material goes around in this accretion disk, it's crushed together through intense friction,

[00:01:57] [SPEAKER_02]: what at the same time being ripped apart at the subatomic level.

[00:02:00] [SPEAKER_02]: In the process releasing vast amounts of energy across the electromagnetic spectrum, but mostly in X-rays.

[00:02:07] [SPEAKER_02]: Eventually the superheated debris passes a point at the inner edge of the accretion disk called the Eventorizen.

[00:02:14] [SPEAKER_02]: This is the point of no return.

[00:02:17] [SPEAKER_02]: The distance from the Black Hole, where the gravitational pull of the Black Hole becomes so strong, escape velocity exceeds the speed of light.

[00:02:25] [SPEAKER_02]: And since nothing can travel faster than the speed of light, the material is doomed to fall forever into the Black Hole singularity,

[00:02:33] [SPEAKER_02]: a place where the laws of physics assigns and distants them breaks down.

[00:02:38] [SPEAKER_02]: But not all the ill-fated materials destined to disappear into the Black Hole.

[00:02:42] [SPEAKER_02]: See, Black Hole's a messy feed is, and so some of this material is captured by powerful magnetic fields before reaching the Eventorizen.

[00:02:51] [SPEAKER_02]: So instead this material is fired out into space perpendicular to the accretion disk, a close to the speed of light.

[00:02:59] [SPEAKER_02]: Price says the simulation provides a new perspective on the final moments of stars in the vicinity of supermassive Black holes.

[00:03:06] [SPEAKER_02]: By capturing the full evolution of the debris astronomers can try and connect the simulations with a growing number of observed star-shrating events identified through telescopic surveys.

[00:03:17] [SPEAKER_02]: Price says the study provides a new avenues of research into the behavior of matter in the most extreme gravitational fields in the known universe.

[00:03:26] [SPEAKER_02]: It also displays fascinating details about the life cycle of stars and Black holes.

[00:03:31] [SPEAKER_02]: However, many aspects of tidal disruption events remain poorly understood.

[00:03:37] [SPEAKER_02]: For example, the new simulation show that this debris forms an asymmetric bubble around the Black Hole,

[00:03:43] [SPEAKER_02]: reprocessing the energy and producing the observed light curves with lower temperatures, faint aluminum in our cities,

[00:03:48] [SPEAKER_02]: and gas velocities of 10,000 to 20,000 kilometres per second.

[00:03:53] [SPEAKER_02]: Other mysteries explained by the new simulations include why tidal disruption events are observed at optical rather than x-ray wavelengths.

[00:04:01] [SPEAKER_02]: Where x-rays would be expected from the equation under the supermassive Black Hole.

[00:04:06] [SPEAKER_02]: Also, why temperature is observed a consistent with a furthest sphere of the star rather than the expected hot-acration disk itself.

[00:04:13] [SPEAKER_02]: Why observe star-shrating events are fainter than expected from models of Black holes efficiently consuming material,

[00:04:20] [SPEAKER_02]: and why the spectra of the observed events finds material expanding towards us at a few percent of the speed of light.

[00:04:26] [SPEAKER_01]: What's amazing actually, when we detect these things.

[00:04:29] [SPEAKER_01]: tidal disruption is just the name for what happens when a star wanders two-closed to the Black Hole in the middle of a galaxy,

[00:04:35] [SPEAKER_01]: so it's supermassive Black Hole and basically gets forgetified.

[00:04:39] [SPEAKER_01]: So it's forgetification, I guess, is the non-technical term for tidal disruption.

[00:04:43] [SPEAKER_01]: It's sort of thing to explain in the middle of galaxies.

[00:04:45] [SPEAKER_01]: So we see this in the middle of other galaxies.

[00:04:47] [SPEAKER_01]: We see it as a transient event, the middle of the galaxy goes bright, so space bright,

[00:04:52] [SPEAKER_01]: or a year or even several years, and so it fades again over time.

[00:04:55] [SPEAKER_01]: And we think this is due to the Black Hole's 90-owned stars.

[00:04:58] [SPEAKER_02]: I remember about what have been a decade ago and now that a large gas cloud was heading towards such a terrace A star,

[00:05:04] [SPEAKER_02]: which is the Supermassive Black Hole, the center of our galaxy,

[00:05:06] [SPEAKER_02]: and it was getting really exciting because it looked like this huge gas cloud was about to be gobbled up by the Supermassive Black Hole.

[00:05:14] [SPEAKER_02]: And we were watching, we were watching, and it made a close pass, and it never happened.

[00:05:18] [SPEAKER_02]: It just went on its merry way, and that was sort of a bit of a lit down really, but ever since then,

[00:05:24] [SPEAKER_02]: just the idea of tidal disruption events has been fascinating and perplexing process for me.

[00:05:30] [SPEAKER_02]: We don't really get to see them close up in personal very often.

[00:05:33] [SPEAKER_01]: I remember the G2 incident quite well, because we were, lots of people predicted what should happen in that case.

[00:05:40] [SPEAKER_01]: And I always funny is that everyone got it completely wrong.

[00:05:43] [SPEAKER_01]: So there's a good example of actually simulation telling you something which didn't match the observation.

[00:05:47] [SPEAKER_02]: At the time, of course, there's still a lot of debate.

[00:05:49] [SPEAKER_02]: Is it a cloud or is it already partially tidal disrupted star?

[00:05:53] [SPEAKER_02]: There was a lot of debate about all that, which made the whole thing even more exciting.

[00:05:57] [SPEAKER_01]: We're actually working on these objects at the moment. That's my next page.

[00:06:00] [SPEAKER_01]: So it's still actually a fascinating question about what those things are in the middle of our galaxy.

[00:06:04] [SPEAKER_01]: As a number of them now called the G object.

[00:06:06] [SPEAKER_01]: The G2 cloud interesting thing hasn't gone away.

[00:06:08] [SPEAKER_02]: The black hole doesn't eat the star all at once, but it tastes drips off it as the star orbits around.

[00:06:15] [SPEAKER_02]: Do you ever get a situation where something really larger, a Supermassive Black Hole maybe a billion times

[00:06:22] [SPEAKER_02]: the massive our Sun?

[00:06:23] [SPEAKER_02]: Well, that's still operate the same way by tearing strips of orbiting star or is that something that could gobble a star in one gulf?

[00:06:30] [SPEAKER_01]: That's a really good question.

[00:06:32] [SPEAKER_01]: So you're exactly right.

[00:06:33] [SPEAKER_01]: So if you start to get to sort of billions of our Black Hole,

[00:06:37] [SPEAKER_01]: and it's all about where something we call the event horizon.

[00:06:40] [SPEAKER_01]: So the event horizon is where, like, kind of escaped from the Black Hole,

[00:06:43] [SPEAKER_01]: and it's like nothing can escape.

[00:06:44] [SPEAKER_01]: And so if that event horizon is very large like it is for a billion solar mass Black Hole,

[00:06:49] [SPEAKER_01]: then you're exactly right.

[00:06:51] [SPEAKER_01]: The star would get completely swallowed whole.

[00:06:53] [SPEAKER_01]: And actually that would be fairly unexciting in the sense that we would not see anything special happen.

[00:06:57] [SPEAKER_01]: So in different galaxies are quite same compared to the galaxy itself, so we would just see nothing happen.

[00:07:02] [SPEAKER_01]: And in fact, we do see evidence for that.

[00:07:04] [SPEAKER_01]: That the title of the selection events that we observe, they come from sort of million or 10 million,

[00:07:10] [SPEAKER_01]: or maybe even some from 100 million solar mass Black Hole,

[00:07:13] [SPEAKER_01]: but when we get to billions of solar mass Black holes was no such a subject.

[00:07:16] [SPEAKER_01]: And so we think that's exactly what you just said, which is that the star just gets swallowed whole.

[00:07:21] [SPEAKER_02]: And we've seen them for a stellar scale as well, haven't we?

[00:07:23] [SPEAKER_02]: We're say two neutron stars merge together.

[00:07:27] [SPEAKER_02]: And sometimes there's a huge explosion, gamma ray burst,

[00:07:30] [SPEAKER_02]: but other times the process suddenly stops and the whole thing disappears,

[00:07:34] [SPEAKER_02]: because it's become a stellar mass Black Hole.

[00:07:36] [SPEAKER_01]: That's a really good analogy as well.

[00:07:38] [SPEAKER_01]: So there are two things that is about the mass ratio.

[00:07:41] [SPEAKER_01]: So it's whether you have two objects of the same mass for the magic together,

[00:07:44] [SPEAKER_01]: or whether you have objects of very different.

[00:07:46] [SPEAKER_01]: So in the case of a star and a Black Hole.

[00:07:48] [SPEAKER_01]: So for example, a neutron star merge up,

[00:07:50] [SPEAKER_01]: the neutron stars would carry taller parts by the times,

[00:07:52] [SPEAKER_01]: and they sort of carry taller part equally.

[00:07:54] [SPEAKER_01]: But that can make every different if you start to get a neutron star on a Black Hole,

[00:07:57] [SPEAKER_01]: then the Black Hole can tear the neutron star part and being relatively unaffected itself.

[00:08:02] [SPEAKER_01]: And so if we come back to the stars and can't dream millions of solar mass Black holes,

[00:08:06] [SPEAKER_01]: then what you tend to get is a Black Hole doesn't tear.

[00:08:09] [SPEAKER_01]: It's just sitting there so much heavier than the star.

[00:08:11] [SPEAKER_01]: But we've had this prediction for a long time,

[00:08:13] [SPEAKER_01]: back in for mountain race, the British astronomer oil in 1988.

[00:08:17] [SPEAKER_01]: He made a very clean prediction which is also seeing an effemulation that around this kind of Black Hole,

[00:08:23] [SPEAKER_01]: stars should mostly come a little bit like comets come towards the Sun.

[00:08:26] [SPEAKER_01]: They tend to come on these what we call parabolic orbits.

[00:08:29] [SPEAKER_01]: So they just get a little kick and they just happen to plunge towards the Sun.

[00:08:33] [SPEAKER_01]: And that's the same with the stars that just gets a little kick in a galaxy.

[00:08:36] [SPEAKER_01]: And it just happens to be the ones towards the Black Hole.

[00:08:38] [SPEAKER_01]: And what happens to the stars becomes bound to the Black Hole,

[00:08:42] [SPEAKER_01]: and half the star just carries on its way.

[00:08:44] [SPEAKER_01]: So if you imagine that happening, what you have is half the star plunging down towards the Black Hole,

[00:08:48] [SPEAKER_01]: half the star being swung away to infinity.

[00:08:51] [SPEAKER_01]: So the star looks gets literally ripping off and stars look like a very very long strand of spaghetti.

[00:08:56] [SPEAKER_01]: And so that's the sort of extreme demonstration.

[00:08:59] [SPEAKER_01]: So we need to get the star that's so much smaller than the Black Hole mass itself.

[00:09:02] [SPEAKER_01]: It just gets forgettified into this big, long thing of pasta.

[00:09:06] [SPEAKER_01]: And then half that strip of pasta then just starts to feed the Black Hole.

[00:09:09] [SPEAKER_01]: Or comes around again on the second package.

[00:09:12] [SPEAKER_01]: And that's what we haven't been able to simulate before is that what happens next.

[00:09:15] [SPEAKER_01]: So that half the star is coming back.

[00:09:17] [SPEAKER_01]: You know, it doesn't just get eaten or does it go around and make an increase in this.

[00:09:21] [SPEAKER_01]: Or does it do something else?

[00:09:23] [SPEAKER_01]: And well, it's quite interesting.

[00:09:24] [SPEAKER_01]: What does happen?

[00:09:25] [SPEAKER_02]: Well, don't leave us in suspense.

[00:09:27] [SPEAKER_01]: Well, so the mystery of the game, how you sort of what we call circular as an material.

[00:09:32] [SPEAKER_01]: So could you fall into some kind of a creation?

[00:09:34] [SPEAKER_01]: And the expectation was yeah, you would swallow our favorite material and generate extra.

[00:09:37] [SPEAKER_01]: But what happens is, like we said, a Black Hole is one of the best ways to generate energy in the universe.

[00:09:43] [SPEAKER_01]: So you only need a little drip feed and you start getting this huge hot power source going in the middle.

[00:09:49] [SPEAKER_01]: It's like a volcano going off.

[00:09:51] [SPEAKER_01]: So you only start to feed a Black Hole.

[00:09:53] [SPEAKER_01]: So the same comes around.

[00:09:54] [SPEAKER_01]: One of the general, to visit the effect is that orbit will process slightly.

[00:09:58] [SPEAKER_01]: So that means the stream actually tends to collide with itself.

[00:10:01] [SPEAKER_01]: A night collision caused a little bit of material to plunge towards the central regions.

[00:10:04] [SPEAKER_01]: And as soon as you start feeding that thing, it starts powering this outflow.

[00:10:09] [SPEAKER_01]: So anything else that comes in just tends to get blown away.

[00:10:11] [SPEAKER_01]: Another way thing about it like we said, the Black Hole is a small object.

[00:10:15] [SPEAKER_01]: It's very hard to stop material down the hole.

[00:10:17] [SPEAKER_01]: So most of the material actually just misses it.

[00:10:19] [SPEAKER_01]: And then you've got this huge heat source in the middle.

[00:10:21] [SPEAKER_01]: And that's just powers.

[00:10:22] [SPEAKER_01]: It's very strong outflow.

[00:10:24] [SPEAKER_01]: And so in fact, that's what we see in part of the solution of that.

[00:10:26] [SPEAKER_01]: So one of the ways that I identified is that when you take a spectrum of these things,

[00:10:29] [SPEAKER_01]: you find that the material is all being flown towards us at 10 or 20,000 kilometres a second.

[00:10:35] [SPEAKER_01]: So that's around 7% of the speed of life.

[00:10:37] [SPEAKER_01]: That's extremely fast.

[00:10:38] [SPEAKER_01]: And so we actually get those kind of speeds in the simulation.

[00:10:41] [SPEAKER_01]: We find this big ball of gas developed.

[00:10:44] [SPEAKER_01]: And the key thing about the ball of gas is it's not see-through.

[00:10:46] [SPEAKER_01]: The like we said before, that's what we call the reprocessing layer or the smothering of the Black Hole.

[00:10:51] [SPEAKER_01]: And that's the thing that hides the x-ray and dizzy this kind of glowing, big ball of material.

[00:10:55] [SPEAKER_01]: But we call it the heading for it on the way, but it's a kind of black hole, solar system size star.

[00:11:00] [SPEAKER_01]: But it's expanding rather than this thing still.

[00:11:02] [SPEAKER_02]: In your simulations, can you compensate for things like time, dialation, have without effect, what's happening?

[00:11:09] [SPEAKER_01]: Yes, those effects are all in the simulation.

[00:11:11] [SPEAKER_01]: That's right. So relativity misses with your mind if you start to think about it.

[00:11:15] [SPEAKER_01]: But I mean, you're absolutely right that those sort of things, for example, material dissemination actually never crosses the event horizon.

[00:11:21] [SPEAKER_01]: So we actually just take a little bit and just delete it if it gets very close.

[00:11:25] [SPEAKER_01]: But according to Einstein's theory, you would never actually watch someone crossing your event horizon the Black Hole from the outside.

[00:11:31] [SPEAKER_02]: I like to say it falls forever.

[00:11:33] [SPEAKER_01]: Indeed. Yeah. So that's, for example, one of the things that just happens naturally in the computer, you do see things we're just fall forever.

[00:11:40] [SPEAKER_01]: But across the internet, that tends to give you an insanity on the code crash.

[00:11:43] [SPEAKER_01]: So which way to, which way to just skip that this?

[00:11:46] [SPEAKER_01]: But you know, it is how the physics works.

[00:11:47] [SPEAKER_02]: That's where the computer says danger will Robinson.

[00:11:50] [SPEAKER_01]: That is one of the tricky bits. It is hard to say exactly what something will look like, especially when you get to raise regions close to Black Hole.

[00:11:57] [SPEAKER_02]: How often do we normally see title disruption events?

[00:11:59] [SPEAKER_01]: So in a galaxy like the Milky Way, we want obviously we can't sit and stare at our Black Hole for millions of years.

[00:12:05] [SPEAKER_01]: But we can see similar other Black Hole in the nearby universe.

[00:12:09] [SPEAKER_01]: So we think, I mean, the rate's actually been going people keep revising it up.

[00:12:13] [SPEAKER_01]: But the current idea is something like once every 100,000 years.

[00:12:16] [SPEAKER_01]: So if you set up a Black Hole for 100,000 years in a galaxy, then a star would get doubled.

[00:12:21] [SPEAKER_01]: Now that sounds like a long time and I said we use for our Milky Way, so we don't expect one in their lifetime.

[00:12:26] [SPEAKER_01]: So yeah, you can imagine it's starting looking at 100,000 galaxies in this planet, in a scale that you would start to get a lot of these events taking place.

[00:12:33] [SPEAKER_02]: And of course there are the evidence of that things like say the Fermi bubbles.

[00:12:37] [SPEAKER_01]: Indeed. Yes. So that's one of the questions I actually used.

[00:12:39] [SPEAKER_01]: We can see that our Black Hole, well it's a bit of a sleeping giant now.

[00:12:42] [SPEAKER_01]: You know we think it's been definitely active in the past.

[00:12:45] [SPEAKER_01]: And we can see as you said some evidence about being the galaxy.

[00:12:48] [SPEAKER_01]: Actually, that's one of the questions that people want to know is because once a Black Hole starts getting active, that's something we call an active molecular nucleus.

[00:12:54] [SPEAKER_01]: It has quite a big effect on the surrounding galaxy.

[00:12:56] [SPEAKER_01]: And so knowing for example, what the duty cycle is, how often this activity comes and goes, it's a little bit like living in the mixture of volcanoes.

[00:13:03] [SPEAKER_01]: You'd like to know what kind of mapping sleeping now, but you'd like to know how often they erupt and how often, you know, if it does erupt, what's going to happen.

[00:13:11] [SPEAKER_01]: And so that's something that people want to know when they started galaxy, what's the sort of effect of having a Black Hole in the middle of the galaxy?

[00:13:17] [SPEAKER_01]: It sort of shuts off a lot of formations, stars and things like that.

[00:13:20] [SPEAKER_01]: So it has a big effect on its surroundings when it gets active like that.

[00:13:23] [SPEAKER_01]: Much like a volcano and sister random villagers.

[00:13:25] [SPEAKER_02]: Being a bud spiral galaxy, as opposed to a, say, a grand design spiral, does that play a different set of circumstances?

[00:13:33] [SPEAKER_02]: In terms of the frequency of black holes, engaging in total disruption events, bud spirals like the Milky Way,

[00:13:41] [SPEAKER_02]: become bud because they have a build up of mass near the center, don't they?

[00:13:44] [SPEAKER_01]: Yeah, so the bud tends to develop for many instability in the pattern of stars over the black hole.

[00:13:49] [SPEAKER_01]: And one of the things that we think happens about separating bud spiral galaxy is the more efficient flow of gas towards essential black hole.

[00:13:56] [SPEAKER_01]: Actually there is an association of a particular kind of galaxy and part of a disruption event.

[00:14:01] [SPEAKER_01]: And it's not fully understood why that is, but it tends to be in more sort of elliptical looking galaxy that you seem to get these things going off.

[00:14:09] [SPEAKER_01]: We don't fully understand that there are some possible explanations for why that association might be the case.

[00:14:14] [SPEAKER_01]: But it's not fully understood.

[00:14:15] [SPEAKER_01]: But obviously one of the things that you could do in a spiral galaxy or a grand design spiral is you have maybe a lot more gas like and you could feed a bunch of gas to the central black hole.

[00:14:23] [SPEAKER_01]: And when that happens, that's more likely to produce something we call a quasar or actually directly to the nucleus rather than so a total suction of an Israeli sort of discrete snack or a star rather than a continuous screening of the central region.

[00:14:35] [SPEAKER_02]: I guess if you've got a quasar or something like that, you're blowing material away too from the black hole and that material could be stars whereas when you're old red and dead, meaning an elliptical galaxy, then you haven't got that much gas there anymore.

[00:14:49] [SPEAKER_02]: So the stars are orbiting any which way including loose so anything possible.

[00:14:55] [SPEAKER_01]: Actually one of the big questions in the field as well is actually how you get very massive black holes in the universe.

[00:15:00] [SPEAKER_01]: So we don't fully understand how black holes grow and one of the mysteries from recent James Webb observations is we're starting to see the sort of billions, all in half, ten billions, all in half black holes in the very early universe.

[00:15:12] [SPEAKER_01]: So you know the first maybe hundred million years of the universe which is really when the universe is a young adolescent.

[00:15:17] [SPEAKER_02]: That's going to be just from collapsing gas doesn't it mean you couldn't merge that many stellar mass or intermediate mass black holes together that quickly one would think.

[00:15:25] [SPEAKER_01]: Awesome that that has been the thinking but it still knows unclear if that's true so there's a big question about what were the seeds of the earliest black holes.

[00:15:34] [SPEAKER_01]: Under some evidence that you could maybe do that with stars but maybe ten thousand maybe ten thousand solar mass black holes with just merging stars together.

[00:15:43] [SPEAKER_01]: I want you to go to ten thousand columnist black holes what's made it difficult to get a hundred thousand solar, like all by seeing stars to it.

[00:15:50] [SPEAKER_01]: So it's an open question very definitely not solved but it's not so crazy that you could actually grow black holes by just tightly disrupting stars and emerging black holes together.

[00:15:59] [SPEAKER_01]: This definitely got the preferred idea but it's not completely not specific.

[00:16:03] [SPEAKER_02]: Of course the universe was much closer together thing back then so yes, we're a lot closer anyway so they were closer to their black holes.

[00:16:12] [SPEAKER_01]: Well that's one of the things that we think for example, our remnants of things like the globe and the clusters in our own galaxies, I'd look up the night sky you'll see on the story.

[00:16:19] [SPEAKER_01]: We think those are little intense bursts of star formation that's a place in that early part of the universe.

[00:16:25] [SPEAKER_01]: So those kind of really dense star clusters they could probably much more easily make black holes and while one of the challenges in global the cost is into look for these immediate mass black holes.

[00:16:34] [SPEAKER_01]: You know some evidence that they seem to be there.

[00:16:37] [SPEAKER_02]: They're just found in a biggest and turret in there.

[00:16:39] [SPEAKER_01]: Yeah I think it was certainly claims that our things in there get nice black holes and maybe by global cost.

[00:16:44] [SPEAKER_02]: Well there's something like a hundred and fifty of them opening our galaxies, this plate is too strong.

[00:16:48] [SPEAKER_01]: But so the thing about their got the clusters is they're really old so that's there what we call low Middle East city stars so that's started with our lots of hydrogen helium and not many of the heavier elements.

[00:16:57] [SPEAKER_01]: And those we think come from the very universe so for example dating some of those called it the clusters within some of them maybe up to 12 billion years old.

[00:17:05] [SPEAKER_01]: There was an old problem that they were actually older than the universe itself which was a bit of an issue that people fixed that with better distance estimates and it seems all that up again.

[00:17:13] [SPEAKER_01]: But you know they are sort of remnants from that early stage of the universe.

[00:17:16] [SPEAKER_01]: Well we think probably things are a bit more violent and a bit more you know as soon as it's a bit easier to form these very dense star clusters for example.

[00:17:22] [SPEAKER_02]: That's Professor Daniel Price from Monash University and this space time still to come new revelations about the composition of the Earth's mantle and the discovery that water is actually fairly widespread across the surface of the moon you just got to know where to look.

[00:17:40] [SPEAKER_02]: Oh that and more still to come on space time.

[00:18:00] [SPEAKER_02]: Well it looks like it's time to re-write the geological textbooks of the planet.

[00:18:04] [SPEAKER_02]: And you study is found that the chemical composition of the Earth's mantle is basically the same everywhere and only changes into unique compositions as it passes through different layers of crust closer to the planet surface.

[00:18:17] [SPEAKER_02]: The new findings reported in the journal Nature Gears Science based on an evaluation of volcanic hotspots around the globe.

[00:18:24] [SPEAKER_02]: It shows that lovers from hotspots, whether erupting in Hawaii, Samoa or Iceland, likely all originate from what appears to be a worldwide uniform reservoir in the Earth's mantle.

[00:18:37] [SPEAKER_02]: It means the Earth's mantle is far more chemically homogenous than scientists previously thought.

[00:18:42] [SPEAKER_02]: One of the study's authors, Mattay Schmidt from the University of British Columbia, says that a discovery quite literally turns sciences view of hotspot lovers in the mantle upside down.

[00:18:53] [SPEAKER_02]: He says, in a way, the Earth's lovers are much like the human race, a beautifully diverse population with a common ancestor but which developed differently wherever it went.

[00:19:04] [SPEAKER_02]: Of course, research into Earth's mantle has always been complicated, other simple fact that it can't be sampled directly.

[00:19:10] [SPEAKER_02]: So instead, researchers need to engage in a bit of geoscientific detective work.

[00:19:15] [SPEAKER_02]: They study this important part of the planet through trace element isotopic analysis of the lovers that come from the mantle and which is erupted at oceanic volcanoes around the world.

[00:19:26] [SPEAKER_02]: The vast differences in composition in these lovers, along with the assumption that the isotopic composition of magma doesn't change between its source and the surface, as wrongly led to a general view that metals contain distinct reservoirs of different ages, located in different regions and formed by different processes.

[00:19:45] [SPEAKER_02]: The observations made by Schmidt and colleagues, however, indicate the reality could be quite different.

[00:19:51] [SPEAKER_02]: Schmitz is by looking at a specific set of elements, scientists were able to discern chemical effects of various processes that act on magma melt on their way to the surface.

[00:20:01] [SPEAKER_02]: And this allowed them to discover that all hotspot lovers actually share the same starting composition.

[00:20:07] [SPEAKER_02]: That means the lab is only come out differently on the surface because the magma's are interacting with different geology as they ascend up through the crust.

[00:20:16] [SPEAKER_02]: The Earth's mantle is a seething layer of molten and semi-multon material comprising about 84% of the planets of volume lying between the Earth's liquid ion at a core and its thin surface crust.

[00:20:28] [SPEAKER_02]: When magma derive from the mantle penetrates the crust and erupts under the surface, it's called lava.

[00:20:35] [SPEAKER_02]: Knowing what the metals made of is centered to scientists understanding of how the planet formed and how the mantle itself developed in the evolved over time.

[00:20:44] [SPEAKER_02]: It may also provide clues as to why the mantle behaves the way it does.

[00:20:48] [SPEAKER_02]: How it drives plate-tech tonics and what its role is in the global cycle of elements.

[00:20:53] [SPEAKER_02]: Despite shedding entirely new light on hotspot lovers in Oceanic parts of the world, Enelis is also reveals an exciting new link to episodic lovers on continents.

[00:21:04] [SPEAKER_02]: These melts, which contain diamond-bearing canberlites, are fundamentally different from magma's found at Oceanic hotspots.

[00:21:11] [SPEAKER_02]: But they nevertheless still have the same magma ancestor.

[00:21:14] [SPEAKER_02]: This discovery really is a game-changer when it comes to models of Earth's chemical evolution and how science looks at global elemental cycles.

[00:21:23] [SPEAKER_02]: Not only is the mantle much more homogenous than previously thought, it likely also no longer contains primordial reservoirs.

[00:21:31] [SPEAKER_02]: These were entities that were once thought to exist and were needed to explain the data scientists were seeing.

[00:21:37] [SPEAKER_02]: Trouble is, though hypothesis of these things could never really be reconciled with the very concept of mantle convection.

[00:21:45] [SPEAKER_02]: And so now thanks to this new study, we can dismiss it completely. This is space-time.

[00:21:51] [SPEAKER_02]: Still to come, scientists discover there are far more widespread water resources on the moon than previously thought you've just got to know where to look.

[00:21:58] [SPEAKER_02]: And later in the science report, Enelis study finally pins down where the Australian wild dog the Dingo really originated from.

[00:22:07] [SPEAKER_02]: Oh that and more still to come. I'm space-time.

[00:22:25] [SPEAKER_02]: A new analysis of maps from both the near and far sides of the moon, a showing scientist at the lunar surface contains vast amounts of water.

[00:22:34] [SPEAKER_02]: Trouble is, it's mostly locked in the lunar regolith. The findings reported in the planetary science journal suggested that there are multiple sources of water and hydroxyl in some of it rocks and soils, including water-rich rocks excavated by meteor impacts at all lunar latitudes.

[00:22:50] [SPEAKER_02]: By the way, hydroxyls are functional chemical groups of molecules comprising a single hydrogen and a single oxygen atom, but missing the second hydrogen atom needed to turn into a water molecule.

[00:23:03] [SPEAKER_02]: See, the solar wind carries normal hydrogen atoms to the moon with the molecules interact with oxygen already on the surface, the form both hydroxyls and water.

[00:23:12] [SPEAKER_02]: The studies lead author, Roger Clark from the planetary science institute, says Future astronaut should be able to find water even near the equator simply by exploiting these water-rich areas.

[00:23:23] [SPEAKER_02]: Previously it was thought that only lunar polar regions and in particular the deeply shattered creators at the poles where sunlight never reaches the crater floor were likely to contain abundant water supplies frozen as ice.

[00:23:35] [SPEAKER_02]: Clark says knowing where the water is located not only helps scientists better understand lunar geologic history but also where astronauts may find water in the future.

[00:23:46] [SPEAKER_02]: That water could then be used for drinking or split up to be turned into rocket fuel or simply for breathing.

[00:23:52] [SPEAKER_02]: Clark and colleagues base their findings, undated from the Moon mineralology-mapar imaging spectrometer aboard the Indian Chandra in once spacecraft, which orbited the Moon during 2008 and 2009, mapping water and hydroxyl on both the near and far sides of the Moon in far greater detail than it ever been done before.

[00:24:11] [SPEAKER_02]: The map are used in ferrets spectroscopy to search for the fingerprints of both water and hydroxyl in the spectra reflected sunlight on the lunar surface.

[00:24:21] [SPEAKER_02]: While a digital camera records three colors in the visible part of electromagnetic spectrum, the map or instrument recorded 85 colors in the visible spectrum and also will into the infrared.

[00:24:31] [SPEAKER_02]: Just like we see different colors from different materials, the infrared spectrometer can see many infrared colors to better determine the composition and that includes water and hydroxyl.

[00:24:42] [SPEAKER_02]: The water may be directly harvested by heating rocks and soils.

[00:24:46] [SPEAKER_02]: The water can also be formed by chemical reactions, liberating hydroxyl and combining four hydroxyls to create oxygen and water.

[00:24:55] [SPEAKER_02]: By studying the location in geologic context, you'll think it's able to show that water in the lunar surface is mutastable.

[00:25:02] [SPEAKER_02]: Many H2O is slowly destroyed over millions of years, but with hydroxyl the OH remaining.

[00:25:09] [SPEAKER_02]: Also, a cratering event that exposes subsurface water which rocks to the solar wind will also degrade with time destroying H2O and creating a diffuse aura of hydroxyl OH, but the distraction is slow taking thousands to millions of years.

[00:25:26] [SPEAKER_02]: Else wrong the lunar surface, there appears to be a container of hydroxyl probably created by solar wind protons impacting the lunar surface, destroying silicon minerals with the protons combined with oxygen in the silicates in order to create hydroxyls in a process called space we're the ring.

[00:25:43] [SPEAKER_02]: Putting all the evidence together, Clark and colleagues see a lunar surface with complex geology with significant water in the subsurface and a surface layer of hydroxyl.

[00:25:53] [SPEAKER_02]: Both cratering and volcanic activity can bring water-rich materials to the surface, and both are observed in the lunar data.

[00:26:02] [SPEAKER_02]: Our moon is made up primarily of two kinds of rocks.

[00:26:06] [SPEAKER_02]: There's the dark marae we see from the Earth which gives us the man in the moon image.

[00:26:11] [SPEAKER_02]: This is basically basaltic rock, like solidified lava.

[00:26:14] [SPEAKER_02]: Then there's the Andesitic rocks which are lighter and fan in the lunar highlands.

[00:26:20] [SPEAKER_02]: It's the Andesites which contain lots of water while the basalts contain very little.

[00:26:26] [SPEAKER_02]: The study also sheds new light, unprevously known mysteries.

[00:26:30] [SPEAKER_02]: When the sunlight is shining on the lunar surface at different times the day, the strength of water and hydroxyl absorptions change.

[00:26:37] [SPEAKER_02]: That led to the calculation that a lot of the water and hydroxyl had to be moving around the moon on a daily cycle.

[00:26:44] [SPEAKER_02]: However, this new study showed that very stable mineral absorption of water and hydroxyl show the same daily effect.

[00:26:52] [SPEAKER_02]: But on minerals like pyroxin, a common igneous silicate material on the lunar surface they don't evaporate at lunar temperatures.

[00:26:58] [SPEAKER_02]: The reason for this effect is instead due to a thin layer of enriched composition and or soul particle size that's different from deeper down in the soil.

[00:27:08] [SPEAKER_02]: So when the sun is low in the lunar sky, light transmits through more of this top layer, strengthening the infrared absorptions compared to when the sun is higher in the sky.

[00:27:18] [SPEAKER_02]: Now don't get me wrong, there may still be water moving around, but to know how much, your studies will be needed to quantify the layering effects.

[00:27:25] [SPEAKER_02]: Also, if you recall the lunar rover tracks appear to be darker in images from the Apollo era rovers, that's another indicated that the surface layer is thin and very different.

[00:27:37] [SPEAKER_02]: Related to this thin surface layer of expressions of enigmatic features on the moon called lunar swirls.

[00:27:44] [SPEAKER_02]: These are diffuse patterns invisible light and several areas on the moon.

[00:27:47] [SPEAKER_02]: Now, its magnetic fields which I thought to play a role in swall formation by diverting solar wind which would also reduce hydroxyl production.

[00:27:56] [SPEAKER_02]: That matches up with earlier studies which show that lunar swirls are deficient in hydroxyl.

[00:28:02] [SPEAKER_02]: The new static confirms this but also shows more complexity. That is the swirls are also low in water content.

[00:28:08] [SPEAKER_02]: But sometimes higher in pyroxine content. This new study using lunar global hydroxyl maps, all she shows never before seen areas that are similar to not swirls but have no diffuse patterns seen in visible light.

[00:28:22] [SPEAKER_02]: Thus can only be seen in hydroxyl absorption. These new features may in fact be older-rooted swirls and include new types including arcs and linear features.

[00:28:32] [SPEAKER_02]: By mapping the moon in your ways like this, the lunar surface is showing scientists that its far more complex than previously thought.

[00:28:40] [SPEAKER_02]: Good to know as we move closer to the Artemis 3 mission in 2026 and man's return to the lunar surface. This is space time.

[00:29:06] [SPEAKER_02]: And time that it took a brief look at some of the other stories making using science this week with the science report.

[00:29:13] [SPEAKER_02]: The climate models are warning that future droughts could be even worse than previously thought. A report in the journal Nature claims,

[00:29:21] [SPEAKER_02]: scientists calibrated models with historical observations of the longest annual dry spells that is the longest number of consecutive dry days each year between 1998 and 2018.

[00:29:33] [SPEAKER_02]: They found the average longest period of drought could end up being 10 days longer by the end of the century than previously predicted.

[00:29:41] [SPEAKER_02]: You'll also say the findings emphasize the need for a reassessment of drought risks around the world and they highlight the importance of correcting existing biases and climate models to increase confidence in their projections.

[00:29:54] [SPEAKER_02]: A new study claims just taking three minutes of exercise every half hour in the evenings could help you sleep.

[00:30:02] [SPEAKER_02]: The findings reported in the British Medical Journal based on a small study investigating how exercise laid in the day could impact on sleep.

[00:30:10] [SPEAKER_02]: The authors recruited 28 people to wear trackers and then monitored their activity in sleep.

[00:30:15] [SPEAKER_02]: On two days at that a week apart there are each asked to spend 4 hours in the lab from around 5 p.m. in the afternoon.

[00:30:22] [SPEAKER_02]: In one of these sessions the participants set for an entire 4 hours.

[00:30:27] [SPEAKER_02]: While in the other they completed an equipment free 3 minute resistance exercise program every half hour.

[00:30:33] [SPEAKER_02]: The authors found that the participant slept for an average of 27 minutes longer after they did the exercise program session compared to the simply sitting around session with no differences in sleep quality.

[00:30:46] [SPEAKER_02]: New archaeological research has discovered clear links between fossils of the iconic Australian native dog The Dingo and dogs from East Asia and Papua New Guinea.

[00:30:57] [SPEAKER_02]: The findings published in the journal Scientific Reports suggested that the Dingo must have come from East Asia via Malaysia and it challenges previous hypotheses that the dogs arrived from India or Thailand.

[00:31:09] [SPEAKER_02]: Previous studies had used traditional morphometric analysis. This looks at the size and shape of the animal using calipers in order to trace the Dingo's ancestry to South Asia.

[00:31:20] [SPEAKER_02]: However, the new study used more sophisticated 3D scanning techniques combined with geometric morphometrics on ancient Dingo specimens to clearly show that they're really most similar to Japanese dogs as well as the singing dogs of Papua New Guinea and the highland wild dogs of Aryan Gia.

[00:31:37] [SPEAKER_02]: The authors also found that modern day Dingo's have evolved to become larger and leaner, standing an average of 54 cm tall compared to between 40 and 47 cm for their ancient ancestors, a size which is also much closer to their contemporary relatives in South East Asia and Malaysia.

[00:31:56] [SPEAKER_02]: But seems the latest fat in Japan in the United States for the paranormal inclined is what they're calling a ghost detecting stone.

[00:32:05] [SPEAKER_02]: It's claimed that this stone changes colour when ghosts, angels or evil spirits, and lurking about.

[00:32:11] [SPEAKER_02]: Now of course the first problem is we're assuming that ghosts, angels and evil spirits are real.

[00:32:17] [SPEAKER_02]: It's also got the problem that it's not really a stone, it's just a chunk of plastic with some electronics and a battery inside.

[00:32:24] [SPEAKER_02]: And at $100 in Aussie dollars, it ain't cheap. So does it work?

[00:32:29] [SPEAKER_02]: Well I guess that depends on whether or not you want to believe as to mend them from Australian skeptics explains.

[00:32:35] [SPEAKER_00]: It's weird. It's little same that the size of a couple of centimetres across the earth or if you're around about that size, that's a probably changed colour when they're surrounded by some to the paranormal activity.

[00:32:45] [SPEAKER_00]: They sell for about $60 USD so it's in Australia money is $100 or not cheap.

[00:32:50] [SPEAKER_00]: But they supposedly change colour when they glow. They glow green during unusual paranormal activity. They glow blue when there's an angelic presence and they glow red when it goes to their dry.

[00:33:01] [SPEAKER_00]: So I'm not sure whether the paranormal activity is compared to it goes for an angel. But anyway they go through these three colours and basically it's a search mode which is activated manually.

[00:33:10] [SPEAKER_00]: It's hard to tell by the pictures, I don't know in one I should say. And no one up after the main defects was exactly sure how they work. You probably would try to take them apart. They are plastic.

[00:33:19] [SPEAKER_00]: They're not real stones. They're not real stones. They have a sense of that. They're the ever-tuping side of some sort of a sort of do-be-resteaks to this.

[00:33:26] [SPEAKER_00]: The search mode which is the afghan's around there's an automatic mode which a lot of active scams. The environment's every 10 minutes and there's a barrier mode which is designed to block dangerous spirits from harming the user.

[00:33:38] [SPEAKER_00]: I don't think they're exactly the same as what usual mood rings, which were the liquid crystal things that you heated up and they changed because of the change of temperature. They changed colour. Those are indicated in a passion level.

[00:33:48] [SPEAKER_00]: If Japanese being is called Baccata or Aseki, which means they've shown their search for ghost, not particularly a most exciting name.

[00:33:56] [SPEAKER_00]: But yeah and it has a crystal ball pattern side that has made of ABS for my place because it's not a real stone.

[00:34:06] [SPEAKER_02]: I mean, a lot of people buy for the nobody's value. But there are a lot of people out there who are going to buy it because they're serious. They think it's going to help them.

[00:34:17] [SPEAKER_00]: There's a lot of people who use a lot of gadgets. Pick up radio signals that sort of thing. Cozley, seek the officer, set her on their particular handheld device or an app on her.

[00:34:24] [SPEAKER_00]: I'll phone something like that. So this is mostly something that will give you an indication if there's something there. So does these apps and a little portable device is to the same thing.

[00:34:34] [SPEAKER_00]: I don't think you can record the event for just an indicator, whereas a handheld device or an app might record signals radio signals, electronic voice signals, that sort of thing.

[00:34:45] [SPEAKER_00]: And probably voice patterns. Sorry, that sort of stuff. So if it's up to now, this is a feeling of work.

[00:34:51] [SPEAKER_00]: And I'm not going to assume that by a long way. You have to have more of the passing interest. You'll use it once a time. Then they'll go in the draw. I'll be in the left there for every minute. Put that out to one thing. What's the reason? There are alternatives. I don't think serious goes to hunters would use it.

[00:35:05] [SPEAKER_00]: That's very much. People doing a weed to board and say, off to the middle of the night having a fun and a few drinks might put it down to see.

[00:35:15] [SPEAKER_02]: That's to mend them from Australian skeptics. And that's the show for now.

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