Source:
https://www.spreaker.com/episode/s27e115-black-hole-star-feasts-earth-s-mantle-mystery-and-lunar-water-abundance--62073685
SpaceTime Series 27 Episode 115
*How Black Holes Eat Stars
Astronomers have developed a groundbreaking computer simulation detailing how supermassive black holes at the centres of galaxies can rip apart and consume entire stars. The study, published in the Astrophysical Journal Letters, provides new insights into the mysterious optical and ultraviolet emissions observed during these catastrophic events. Lead author Daniel Price from Monash University explains that the simulation captures the full evolution of the debris from a star being tidally disrupted by a black hole.
*New Revelations About Earth’s Mantle
A new study reveals that the chemical composition of the Earth's mantle is uniform globally and only changes as it passes through different layers of crust closer to the planet's surface. Reported in the journal Nature Geoscience, the findings suggest that lavas from volcanic hotspots around the world likely originate from a worldwide uniform reservoir in the Earth's mantle.
*Water More Widespread on the Moon Than Previously Thought
New maps from both the near and far sides of the Moon show that the lunar surface contains vast amounts of water, mostly locked in the lunar regolith. The findings, published in the Planetary Science Journal, suggest multiple sources of water and hydroxyl in sunlit rocks and soils, including water-rich rocks excavated by meteor impacts at all lunar latitudes.
https://www.spacetimewithstuartgary.com
https://www.bitesz.com
This week’s guests include: Professor Daniel Price from Monash University
🌏 Get Our Exclusive NordVPN deal here ➼ https://www.bitesz.com/nordvpn The discount and bonuses are incredible! And it’s risk-free with Nord’s 30-day money-back guarantee! ✌
Check out our newest sponsor - https://www.bitesz.com/oldglory. Well worth a look....
00:00:00 --> 00:00:04 this is spacetime series 27 episode 115
00:00:04 --> 00:00:06 for broadcast on the 23rd of September
00:00:07 --> 00:00:10 2024 coming up on SpaceTime how black
00:00:10 --> 00:00:13 holes eat Stars New Revelations about
00:00:13 --> 00:00:17 the Earth's mantle and it seems water is
00:00:17 --> 00:00:19 far more widespread on the moon than
00:00:19 --> 00:00:21 previously thought all that and more
00:00:21 --> 00:00:24 coming up on
00:00:24 --> 00:00:27 SpaceTime welcome to SpaceTime with
00:00:27 --> 00:00:29 Stuart Gary
00:00:29 --> 00:00:36 [Music]
00:00:44 --> 00:00:45 astronomers have developed a new
00:00:45 --> 00:00:48 computer simulation detailing how
00:00:48 --> 00:00:50 monstrous black holes at the centers of
00:00:50 --> 00:00:52 galaxies can physically rip apart and
00:00:52 --> 00:00:56 consume an entire star the new research
00:00:56 --> 00:00:58 reported in the astrophysical journal
00:00:58 --> 00:01:00 letters captures this complex process in
00:01:00 --> 00:01:03 great detail also providing new insights
00:01:03 --> 00:01:05 into the mysterious Optical and
00:01:05 --> 00:01:07 UltraViolet emissions observed during
00:01:07 --> 00:01:10 these catastrophic events the study's
00:01:10 --> 00:01:12 lead author Daniel price from manash
00:01:12 --> 00:01:14 University says the program represents
00:01:14 --> 00:01:16 the first self-consistent simulation of
00:01:16 --> 00:01:18 a star being tily disrupted by a super
00:01:18 --> 00:01:20 massive black hole followed by the
00:01:20 --> 00:01:22 evolution of the resulting debris over
00:01:22 --> 00:01:25 the course of a year when a star passes
00:01:25 --> 00:01:28 too close to a super massive black hole
00:01:28 --> 00:01:30 the intense gravitational force forces
00:01:30 --> 00:01:32 of the black hole tear the star apart in
00:01:32 --> 00:01:34 a process called a tidal disruption
00:01:35 --> 00:01:37 event the debris from the unfortunate
00:01:37 --> 00:01:40 star then forms a stream of material
00:01:40 --> 00:01:41 which will eventually feed into the
00:01:41 --> 00:01:44 black hole but this material doesn't
00:01:44 --> 00:01:46 disappear down the black hole all at
00:01:46 --> 00:01:49 once first it creates a swirling
00:01:49 --> 00:01:51 accretion disc around the black hole and
00:01:51 --> 00:01:53 as the material goes around in this
00:01:53 --> 00:01:55 accretion disc it's crushed together
00:01:55 --> 00:01:57 through intense friction while at the
00:01:57 --> 00:01:59 same time being ripped apart at the sub
00:02:00 --> 00:02:02 Atomic level in the process releasing
00:02:02 --> 00:02:04 vast amounts of energy across the
00:02:04 --> 00:02:06 electromagnetic spectrum but mostly in
00:02:06 --> 00:02:09 x-rays eventually the superheated debris
00:02:09 --> 00:02:11 passes a point at the inner edge of the
00:02:11 --> 00:02:14 accretion disc called The Event Horizon
00:02:14 --> 00:02:17 this is the point of no return the
00:02:17 --> 00:02:19 distance from the black hole where the
00:02:19 --> 00:02:20 gravitational pull of the black hole
00:02:21 --> 00:02:23 becomes so strong escape velocity
00:02:23 --> 00:02:26 exceeds the speed of light and since
00:02:26 --> 00:02:28 nothing can travel faster than the speed
00:02:28 --> 00:02:30 of light the material is due doomed to
00:02:30 --> 00:02:32 fall forever into the black hole
00:02:32 --> 00:02:34 Singularity a place where the laws of
00:02:34 --> 00:02:36 physics as science understands them
00:02:36 --> 00:02:39 breaks down but not all the ill- FedEd
00:02:39 --> 00:02:41 materials destined to disappear into the
00:02:41 --> 00:02:44 black hole see black holes are messy
00:02:44 --> 00:02:46 feeders and so some of this material is
00:02:47 --> 00:02:49 captured by powerful magnetic fields
00:02:49 --> 00:02:51 before reaching the Event Horizon so
00:02:51 --> 00:02:54 instead this material is fired out into
00:02:54 --> 00:02:55 space perpendicular to the accretion
00:02:55 --> 00:02:58 disc at close to the speed of
00:02:58 --> 00:03:00 light price says the simulation provides
00:03:00 --> 00:03:02 A New Perspective on the final moments
00:03:02 --> 00:03:04 of stars in the vicinity of super
00:03:05 --> 00:03:07 massive black holes by capturing the
00:03:07 --> 00:03:09 full evolution of the debris astronomers
00:03:09 --> 00:03:12 can try and connect the simulations with
00:03:12 --> 00:03:13 a growing number of observed star
00:03:13 --> 00:03:15 Shredding Events identified through
00:03:15 --> 00:03:18 telescopic surveys price says the study
00:03:18 --> 00:03:20 provides new avenues of research into
00:03:20 --> 00:03:22 the behavior of matter in the most
00:03:22 --> 00:03:24 extreme gravitational fields in the
00:03:24 --> 00:03:27 known universe it also displays
00:03:27 --> 00:03:29 fascinating details about the life cycle
00:03:29 --> 00:03:33 of stars and black holes however many
00:03:33 --> 00:03:35 aspects of tidal disruption events
00:03:35 --> 00:03:38 remain poorly understood for example the
00:03:38 --> 00:03:40 new simulation show that this debris
00:03:40 --> 00:03:42 forms an asymmetric bubble around the
00:03:42 --> 00:03:44 black hole reprocessing the energy and
00:03:44 --> 00:03:46 producing The observed light curves with
00:03:46 --> 00:03:48 lower temperatures fainter luminosities
00:03:48 --> 00:03:52 and gas velocities of 10 to 20
00:03:52 --> 00:03:55 km/s other Mysteries explained by the
00:03:55 --> 00:03:57 new simulations include why tidle
00:03:57 --> 00:03:59 disruption events are observed at
00:03:59 --> 00:04:01 Optical r rather than x-ray wavelength
00:04:01 --> 00:04:03 or x-rays would be expected from the
00:04:03 --> 00:04:05 accretion onto the super massive black
00:04:05 --> 00:04:08 hole also why temperatures observed are
00:04:08 --> 00:04:09 consistent with the Photosphere of the
00:04:09 --> 00:04:12 star rather than the expected hotter
00:04:12 --> 00:04:14 cretion disc itself why observed star
00:04:14 --> 00:04:16 shredding events are fainter than
00:04:16 --> 00:04:18 expected from models of black holes
00:04:18 --> 00:04:20 efficiently consuming material and why
00:04:20 --> 00:04:22 the Spectre of the observed events finds
00:04:22 --> 00:04:25 material expanding towards us at a few
00:04:25 --> 00:04:27 per of the speed of light what's amazing
00:04:27 --> 00:04:29 actually we can even detect these things
00:04:29 --> 00:04:31 so tit disruption is just the name for
00:04:31 --> 00:04:33 what happens when a star wanders too
00:04:33 --> 00:04:35 close to the black hole in the middle of
00:04:35 --> 00:04:37 the Galaxy so a super massive black hole
00:04:37 --> 00:04:39 and basically gets spaghettified so
00:04:39 --> 00:04:40 spaghettification I guess is the
00:04:41 --> 00:04:42 non-technical term for tital disruption
00:04:43 --> 00:04:44 this sort of thing takes place in the
00:04:44 --> 00:04:45 middle of the galaxies so we see this in
00:04:46 --> 00:04:47 the middle of other galaxies we see it
00:04:48 --> 00:04:49 as a transient event the middle of the
00:04:49 --> 00:04:52 Galaxy goes bright so stays bright for a
00:04:52 --> 00:04:54 year or even several years and sort of
00:04:54 --> 00:04:55 Fades again over time and we think this
00:04:55 --> 00:04:57 is Du the black hole snacking on Stars I
00:04:58 --> 00:04:59 remember about it would have been a DEC
00:04:59 --> 00:05:01 ago now that a large gas cloud was
00:05:01 --> 00:05:04 heading towards Sagittarius AAR which is
00:05:04 --> 00:05:05 the supermassive black hole at the
00:05:05 --> 00:05:07 center of our galaxy and it was getting
00:05:07 --> 00:05:09 really exciting because it looked like
00:05:09 --> 00:05:11 this huge gas cloud was about to be
00:05:11 --> 00:05:13 gobbled up by the super massive black
00:05:13 --> 00:05:15 hole and we were watching we were
00:05:15 --> 00:05:18 watching and it made a close pass and it
00:05:18 --> 00:05:20 never happened it just went on its merry
00:05:20 --> 00:05:22 way and that was sort of a bit of a
00:05:22 --> 00:05:24 letdown really but ever since then just
00:05:24 --> 00:05:26 the idea of title disruption events has
00:05:26 --> 00:05:29 been a fascinating and uh perplexing
00:05:29 --> 00:05:31 process for me we don't really get to
00:05:31 --> 00:05:33 see them close up and personal very
00:05:33 --> 00:05:35 often actually I remember the G2
00:05:35 --> 00:05:38 incident quite well because we were lots
00:05:38 --> 00:05:39 of people predicted what should happen
00:05:39 --> 00:05:41 in that case uh what was funny is that
00:05:41 --> 00:05:43 everyone got it completely wrong so
00:05:43 --> 00:05:44 there's a good example of actually
00:05:44 --> 00:05:46 simulations telling you something which
00:05:46 --> 00:05:48 didn't matter observation at the time of
00:05:48 --> 00:05:49 course there's still a lot of debate is
00:05:49 --> 00:05:51 it a cloud or is it already partially
00:05:51 --> 00:05:53 title disrupted star indeed there was a
00:05:54 --> 00:05:55 lot of debate about all that which made
00:05:55 --> 00:05:57 the whole thing even more exciting we're
00:05:57 --> 00:05:58 actually working on these G objects at
00:05:58 --> 00:06:01 the moment that's my next Pap so it's
00:06:01 --> 00:06:02 still actually a fascinating question
00:06:02 --> 00:06:03 about what those things are in the
00:06:03 --> 00:06:05 middle of our galaxies as number of them
00:06:05 --> 00:06:07 now called the G objects the G2 Cloud
00:06:07 --> 00:06:08 interesting thing hasn't gone away the
00:06:08 --> 00:06:10 black hole doesn't eat the star all at
00:06:10 --> 00:06:13 once but it tears strips off it as the
00:06:13 --> 00:06:15 star orbits around do you ever get a
00:06:15 --> 00:06:19 situation where something really large a
00:06:19 --> 00:06:21 super massive black hoold maybe a
00:06:21 --> 00:06:23 billion times the mass of our sun would
00:06:23 --> 00:06:25 that still operate the same way by
00:06:25 --> 00:06:28 tearing strips off a orbiting star or is
00:06:28 --> 00:06:30 that something that could gobble star in
00:06:30 --> 00:06:32 one go that's a really good question so
00:06:32 --> 00:06:35 you're exactly right so if you start to
00:06:35 --> 00:06:37 get to sort of billion solar mass black
00:06:37 --> 00:06:38 holes all about where is something we
00:06:38 --> 00:06:40 call the Event Horizon so the Event
00:06:40 --> 00:06:42 Horizon is where light can't escape from
00:06:42 --> 00:06:43 the black hole in fact nothing can
00:06:43 --> 00:06:46 escape and so if that event horizon is
00:06:46 --> 00:06:48 very large like it is for a billion
00:06:48 --> 00:06:50 solar mass black hole then you're
00:06:50 --> 00:06:51 exactly right the star would get
00:06:51 --> 00:06:53 completely swalled hole and actually
00:06:53 --> 00:06:55 that would be fairly unexciting in the
00:06:55 --> 00:06:56 sense that we would not see anything
00:06:56 --> 00:06:59 special happen do in dist galaxies are
00:06:59 --> 00:07:01 quite compared to the Galaxy itself so
00:07:01 --> 00:07:02 we would just see nothing happen and in
00:07:02 --> 00:07:04 fact we do see evidence for that that
00:07:04 --> 00:07:06 the tidal disruption events that we
00:07:06 --> 00:07:08 observe they come from sort of million
00:07:08 --> 00:07:11 or 10 million or maybe even some from
00:07:11 --> 00:07:13 100 million solar mass blacks but when
00:07:13 --> 00:07:15 we get to a billion solar mass blacks
00:07:15 --> 00:07:17 there's no disruption of anything and so
00:07:17 --> 00:07:18 we think that's exactly what you just
00:07:18 --> 00:07:20 said which is that the Stars just get
00:07:20 --> 00:07:22 swallowed whole and we've seen that the
00:07:22 --> 00:07:23 Stellar scale as well haven't we where
00:07:24 --> 00:07:27 say two neutron stars merge together and
00:07:27 --> 00:07:29 sometimes there's a huge explosion M
00:07:29 --> 00:07:32 burst but other times the process
00:07:32 --> 00:07:33 suddenly stops and the whole thing
00:07:33 --> 00:07:35 disappears because it's become a stellar
00:07:35 --> 00:07:37 Mass black hole that's a really good
00:07:37 --> 00:07:39 analogy as well so the key thing is is
00:07:39 --> 00:07:41 about the mass ratio so it's whether you
00:07:41 --> 00:07:43 have two objects of the same mass that
00:07:43 --> 00:07:44 emerging together or whether you have
00:07:44 --> 00:07:46 objects of very different so in the case
00:07:46 --> 00:07:48 of a star in a black hole so for example
00:07:48 --> 00:07:50 a neutron star merger the neutron stars
00:07:50 --> 00:07:52 would tear each other apart by the tides
00:07:52 --> 00:07:54 and they sort of tear each other apart
00:07:54 --> 00:07:55 equally but that can be get very
00:07:55 --> 00:07:56 different if you start to get a neutron
00:07:56 --> 00:07:58 star in a black hole then the black hole
00:07:58 --> 00:08:00 can tear the neutron star part and being
00:08:00 --> 00:08:02 relatively unaffected itself and so if
00:08:02 --> 00:08:04 we come back to the Stars encountering
00:08:04 --> 00:08:07 million solar mass black hols then what
00:08:07 --> 00:08:08 you tend to get is the black ho doesn't
00:08:08 --> 00:08:10 care it's just sitting there it's so
00:08:10 --> 00:08:11 much heavier than the star but we've had
00:08:12 --> 00:08:13 this prediction for a long time back in
00:08:13 --> 00:08:15 from Martin Ree the British astronomer
00:08:15 --> 00:08:18 Royal in 1988 he made a very clean
00:08:18 --> 00:08:20 prediction which is also seen in our
00:08:20 --> 00:08:22 simulation that around this kind of
00:08:22 --> 00:08:24 black hole star should mostly come a
00:08:24 --> 00:08:26 little like like comets come towards the
00:08:26 --> 00:08:27 sun they tend to come on these what we
00:08:27 --> 00:08:29 call parabolic orbits so they're just
00:08:29 --> 00:08:31 they get a little kick and they just
00:08:31 --> 00:08:33 happen to plunge towards the Sun and
00:08:33 --> 00:08:34 that's the same with the star sort of
00:08:34 --> 00:08:36 just gets a little kick in a galaxy and
00:08:36 --> 00:08:37 just happens to plunge towards the black
00:08:38 --> 00:08:40 hole and what happens is half the star
00:08:40 --> 00:08:42 becomes bound to the black hole and half
00:08:42 --> 00:08:44 the star just carries on its way so if
00:08:44 --> 00:08:45 you imagine that happening what you have
00:08:45 --> 00:08:47 is half the star plunging down towards
00:08:47 --> 00:08:49 the black hole half the star being swung
00:08:50 --> 00:08:52 away to Infinity so the star gets
00:08:52 --> 00:08:54 literally ripped in half and starts to
00:08:54 --> 00:08:56 look like a very very long strand of
00:08:56 --> 00:08:58 spaghetti so that's the sort of extreme
00:08:58 --> 00:08:59 M ratio so when you you get to the sell
00:09:00 --> 00:09:01 that's so much smaller than the black H
00:09:01 --> 00:09:03 mous itself it just gets
00:09:03 --> 00:09:05 spaghettified into this big long thing
00:09:05 --> 00:09:07 of pasta and then half that strip of
00:09:07 --> 00:09:09 pasta then just starts to feed the black
00:09:09 --> 00:09:11 hole or what comes comes around again on
00:09:11 --> 00:09:12 a second passage and that's a bit we
00:09:13 --> 00:09:14 haven't been able to simulate before is
00:09:14 --> 00:09:16 that what happens next so that half the
00:09:16 --> 00:09:17 Stars coming back you know does it just
00:09:18 --> 00:09:19 get eaten or does it go around and make
00:09:20 --> 00:09:21 an accretion RK or does it do something
00:09:21 --> 00:09:23 else and well it's quite interesting
00:09:24 --> 00:09:26 what does happen well don't leave us in
00:09:26 --> 00:09:29 suspense well so the mystery of again
00:09:29 --> 00:09:31 how you sort of what we call circularize
00:09:31 --> 00:09:32 that material so could you form it into
00:09:32 --> 00:09:34 some kind of a creation and the
00:09:34 --> 00:09:35 expectation was yeah you would swallow a
00:09:36 --> 00:09:38 fair bit of material and generate x-rays
00:09:38 --> 00:09:40 but what happens is like we said black
00:09:40 --> 00:09:42 hole is one of the best ways to generate
00:09:42 --> 00:09:44 energy in the universe so you only need
00:09:44 --> 00:09:46 a little drip feed and you start getting
00:09:46 --> 00:09:49 this huge hot power source going in the
00:09:49 --> 00:09:51 middle it's like a volcano going off so
00:09:51 --> 00:09:53 you only start to feed the black H so
00:09:53 --> 00:09:54 the stream comes around one of the
00:09:54 --> 00:09:56 general relativistic effects is the
00:09:56 --> 00:09:58 orbit will process slightly so that
00:09:58 --> 00:09:59 means the stream actually ends to
00:09:59 --> 00:10:01 collide with itself and that Collision
00:10:01 --> 00:10:03 causes a little bit of material to
00:10:03 --> 00:10:04 plunge towards the central regions and
00:10:05 --> 00:10:06 as soon as you start feeding that thing
00:10:06 --> 00:10:09 it starts powering this outflow so
00:10:09 --> 00:10:10 anything else that comes in just tends
00:10:10 --> 00:10:12 to get blown away in another way thing
00:10:12 --> 00:10:13 about it like we said the black hole is
00:10:13 --> 00:10:15 a small object it's very hard to stuffed
00:10:15 --> 00:10:17 material down the hole so most of the
00:10:17 --> 00:10:19 material actually just misses but then
00:10:19 --> 00:10:20 you've got this huge heat Source in the
00:10:20 --> 00:10:22 middle and that just Powers this very
00:10:22 --> 00:10:24 strong outflow and so in fact that's
00:10:25 --> 00:10:26 what we see in title disruption events
00:10:26 --> 00:10:28 one of the ways they're identified is
00:10:28 --> 00:10:29 that when you take a spectrum of these
00:10:29 --> 00:10:31 things you find that the material is all
00:10:31 --> 00:10:34 being flung towards us at 10 or 20
00:10:34 --> 00:10:36 km a second so that's around 7% of the
00:10:36 --> 00:10:38 speed of life that's extremely fast and
00:10:38 --> 00:10:40 so we we actually get those kind of
00:10:40 --> 00:10:42 speeds in the simulation we find this
00:10:42 --> 00:10:44 big ball of gas develops and the key
00:10:44 --> 00:10:45 thing about the ball of gas is that it's
00:10:45 --> 00:10:47 not seethrough so like we said before
00:10:47 --> 00:10:49 that's what we call the reprocessing
00:10:49 --> 00:10:50 layer or the smothering of the black
00:10:50 --> 00:10:52 hole and that's the thing that hides the
00:10:52 --> 00:10:53 x-rays and gives you this kind of
00:10:54 --> 00:10:56 glowing big ball of material that we
00:10:56 --> 00:10:58 call it the Edington envelope it's a
00:10:58 --> 00:11:00 kind of black hole system size star but
00:11:00 --> 00:11:02 it's expanding rather than just staying
00:11:02 --> 00:11:04 still in your simulations can you
00:11:04 --> 00:11:07 compensate for things like time dilation
00:11:07 --> 00:11:08 how would that affect what's happening
00:11:08 --> 00:11:10 yeah so those those effects are all in
00:11:10 --> 00:11:12 the simulation that's right so
00:11:12 --> 00:11:13 relativity messes with your mind if you
00:11:13 --> 00:11:15 start to think about it but I mean
00:11:15 --> 00:11:17 you're absolutely right that those sort
00:11:17 --> 00:11:18 of things so for example material in
00:11:18 --> 00:11:20 simulation actually never crosses the
00:11:20 --> 00:11:22 Event Horizon so we actually just cheat
00:11:22 --> 00:11:24 a little bit and just delete it if it
00:11:24 --> 00:11:25 gets very close but according to
00:11:25 --> 00:11:27 Einstein's theory you would never
00:11:27 --> 00:11:29 actually watch someone Crossing event of
00:11:29 --> 00:11:31 the black hole from the outside I like
00:11:31 --> 00:11:34 to say it falls forever indeed yeah so
00:11:34 --> 00:11:36 so that's for example one of the things
00:11:36 --> 00:11:37 that just happens naturally in the
00:11:37 --> 00:11:39 computer you do see things would just
00:11:39 --> 00:11:40 fall forever but of course in a computer
00:11:40 --> 00:11:42 that tends to give you an infinity and
00:11:42 --> 00:11:45 the code crashes so we try to we try to
00:11:45 --> 00:11:46 just skip that bit but you know it is
00:11:47 --> 00:11:48 how the physics works that's when the
00:11:48 --> 00:11:50 computer says danger Will Robinson that
00:11:50 --> 00:11:52 is one of the tricky bits it is hard to
00:11:52 --> 00:11:54 say exactly what something will look
00:11:54 --> 00:11:55 like especially when you get to those
00:11:55 --> 00:11:57 regions closer to by car how often do we
00:11:57 --> 00:11:59 normally see title disruption events so
00:11:59 --> 00:12:02 in a galaxy like the Milky Way I mean
00:12:02 --> 00:12:04 what obviously we can't sit and stare at
00:12:04 --> 00:12:05 our black hole for millions of years but
00:12:05 --> 00:12:08 we can see similar other black H in the
00:12:08 --> 00:12:10 nearby universe so we think I mean the
00:12:10 --> 00:12:12 rat's actually been going people keep
00:12:12 --> 00:12:14 revising it upwards but the current idea
00:12:14 --> 00:12:16 it's something like once every 100
00:12:16 --> 00:12:17 years so if you stared at the black hole
00:12:17 --> 00:12:20 for 100 years in our galaxy then a
00:12:20 --> 00:12:22 star would get gobbled now that sounds
00:12:22 --> 00:12:23 like a long time and it certainly is for
00:12:23 --> 00:12:25 our Milky Way so we don't expect one In
00:12:25 --> 00:12:27 Our Lifetime well yeah you can imagine
00:12:27 --> 00:12:29 if you start looking at 100 G
00:12:29 --> 00:12:31 and there's plenty of them in the sky
00:12:31 --> 00:12:32 that you would start to get a lot of
00:12:32 --> 00:12:34 these events taking place and of course
00:12:34 --> 00:12:35 there'd be evidence of that things like
00:12:35 --> 00:12:37 say the fmy bubbles indeed yeah so
00:12:37 --> 00:12:39 that's one of the questions actually is
00:12:39 --> 00:12:40 we can see that that black hole while
00:12:40 --> 00:12:42 it's a bit of a sleeping giant now you
00:12:42 --> 00:12:44 know we think it's been definitely
00:12:44 --> 00:12:46 active in the past and we can see as you
00:12:46 --> 00:12:47 said some evidence for that in the
00:12:47 --> 00:12:48 Galaxy actually that's one of the
00:12:48 --> 00:12:50 questions that people want to know is
00:12:50 --> 00:12:51 because once a black hole starts getting
00:12:51 --> 00:12:52 active that's something we call an
00:12:52 --> 00:12:54 active Galactic nucleus it has quite a
00:12:54 --> 00:12:56 big effect on the surrounding Galaxy and
00:12:56 --> 00:12:58 so knowing for example you know what the
00:12:58 --> 00:13:01 Judy cycle is so how often this activity
00:13:01 --> 00:13:02 comes and goes it's a little bit like
00:13:02 --> 00:13:04 living next to a volcano you know you'd
00:13:04 --> 00:13:05 like to know volcano might be sleeping
00:13:05 --> 00:13:07 now but you'd like to know how often
00:13:07 --> 00:13:09 they erupt and how often you know if it
00:13:09 --> 00:13:11 does erupt what's going to happen and so
00:13:11 --> 00:13:12 that's something that people want to
00:13:12 --> 00:13:14 know when they study galaxies what's the
00:13:14 --> 00:13:15 sort of effect of having a black hole in
00:13:15 --> 00:13:17 the middle of your Galaxy it sort of
00:13:17 --> 00:13:19 shuts off a lot of formation of stars
00:13:19 --> 00:13:20 and things like that so it has a big
00:13:20 --> 00:13:22 effect on its surroundings when it gets
00:13:22 --> 00:13:24 active like that much like a volcano and
00:13:24 --> 00:13:26 just surrounding Villages being a b
00:13:26 --> 00:13:29 spiral galaxy as opposed to a say a
00:13:29 --> 00:13:32 grand design spiral does that play a
00:13:32 --> 00:13:34 different set of circumstances in terms
00:13:34 --> 00:13:37 of the frequency of black holes engaging
00:13:37 --> 00:13:39 in total disruption events bad spirals
00:13:39 --> 00:13:41 like the Milky Way become bad because
00:13:41 --> 00:13:43 they have a buildup of mass near the
00:13:43 --> 00:13:45 center don't they yeah so the bar tends
00:13:45 --> 00:13:47 to develop from an instability in the
00:13:47 --> 00:13:49 pattern of stars orbiting the black hole
00:13:49 --> 00:13:50 and one of the things that we we think
00:13:50 --> 00:13:53 happens a fair bit in B spal galaxies is
00:13:53 --> 00:13:55 a more efficient flow of gas towards the
00:13:55 --> 00:13:57 central black hole actually there is an
00:13:57 --> 00:13:59 association of a particular kind Galaxy
00:13:59 --> 00:14:01 with title disruption events and it's
00:14:01 --> 00:14:03 not fully understand why that is but it
00:14:03 --> 00:14:05 tends to be in more sort of elliptical
00:14:05 --> 00:14:07 looking galaxies that you seem to get
00:14:07 --> 00:14:09 these things going off and we don't
00:14:09 --> 00:14:11 fully understand that there's some
00:14:11 --> 00:14:12 possible explanations for why that
00:14:12 --> 00:14:14 Association might be the case but it's
00:14:14 --> 00:14:16 not fully understood but obviously one
00:14:16 --> 00:14:17 of the things that you could do in a
00:14:17 --> 00:14:19 spiral galaxy or a grand design spiral
00:14:19 --> 00:14:21 is you have maybe a lot more gas L and
00:14:21 --> 00:14:23 you could feed a bunch of gas to the
00:14:23 --> 00:14:24 central black hole and when that happens
00:14:24 --> 00:14:26 that's more likely to produce something
00:14:26 --> 00:14:29 we call aazar or active Galactic nucleus
00:14:29 --> 00:14:31 rather than so TI disruption event is
00:14:31 --> 00:14:33 really a sort of discret snack on a star
00:14:33 --> 00:14:34 rather than sort of continuous speeding
00:14:34 --> 00:14:36 of the central region I guess if you got
00:14:36 --> 00:14:38 a quazer or something like that you're
00:14:38 --> 00:14:40 blowing material away too from the black
00:14:41 --> 00:14:42 hole and that material could be Stars
00:14:42 --> 00:14:45 whereas when you're old red and dead
00:14:45 --> 00:14:47 meaning an elliptical galaxy then you
00:14:47 --> 00:14:49 haven't got that much gas there anymore
00:14:49 --> 00:14:52 so the the stars are all orbiting Any
00:14:52 --> 00:14:54 Which Way including loose uh so
00:14:54 --> 00:14:55 anything's possible actually one of the
00:14:55 --> 00:14:57 big questions in the field as well is
00:14:57 --> 00:14:59 actually how you get very massive black
00:14:59 --> 00:15:01 holes in the universe so we don't fully
00:15:01 --> 00:15:03 understand how black holes grow and one
00:15:03 --> 00:15:05 of the mysteries from recent James web
00:15:05 --> 00:15:07 observations is we're starting to see
00:15:07 --> 00:15:09 these sort of billion solar mass 10
00:15:09 --> 00:15:11 billion solar mass black holes in the
00:15:11 --> 00:15:12 very early universe so in you know the
00:15:12 --> 00:15:14 first maybe 100 million years of the
00:15:14 --> 00:15:15 universe which is really when the
00:15:15 --> 00:15:17 universe is a young adolescent that's
00:15:17 --> 00:15:19 got me just from collapsing gas doesn't
00:15:19 --> 00:15:21 it I mean you couldn't merge that many
00:15:21 --> 00:15:23 Stellar mass or intermediate M black
00:15:23 --> 00:15:25 holes together that quickly one would
00:15:25 --> 00:15:27 think oh so that that has been the
00:15:27 --> 00:15:29 thinking but it's still you know it's
00:15:29 --> 00:15:31 unclear if that's true so there's a big
00:15:31 --> 00:15:32 question about what were the seeds of
00:15:32 --> 00:15:34 the earliest of black holes and there's
00:15:34 --> 00:15:36 some evidence that you could maybe do
00:15:36 --> 00:15:38 that Withers that are maybe 10 so
00:15:38 --> 00:15:41 you can make maybe 10 solar mass
00:15:41 --> 00:15:42 black holes with just merging stars
00:15:42 --> 00:15:44 together and once you've got a 10
00:15:44 --> 00:15:46 solar mass black hole it's not so
00:15:46 --> 00:15:48 difficult to get a 100 Sol M Black
00:15:48 --> 00:15:50 Hole by feeding stars to it so it's an
00:15:50 --> 00:15:52 open question so it's definitely not
00:15:52 --> 00:15:55 solved but it's not so crazy that you
00:15:55 --> 00:15:57 could actually grow black holes by just
00:15:57 --> 00:15:59 tidally disrupting Stars anding bu HS
00:15:59 --> 00:16:00 together it's definitely not the
00:16:00 --> 00:16:02 preferred idea but it's not completely
00:16:02 --> 00:16:04 nuts to suggest that well of course the
00:16:04 --> 00:16:07 universe was a much closer together
00:16:07 --> 00:16:09 thing back then so stars were a lot
00:16:09 --> 00:16:10 closer anyway so they were closer to
00:16:10 --> 00:16:12 their black holes well that's one of the
00:16:12 --> 00:16:15 things so we think for example remnants
00:16:15 --> 00:16:16 of things like the glob of the Clusters
00:16:16 --> 00:16:17 in IR Galaxy so if you look up at the
00:16:18 --> 00:16:19 night sky you'll see only the centor we
00:16:19 --> 00:16:21 think those are little intense bursts of
00:16:21 --> 00:16:23 star formation that took place in that
00:16:23 --> 00:16:25 early part of the universe so those kind
00:16:25 --> 00:16:27 of you know really Dense Star clusters
00:16:27 --> 00:16:28 they could probably much more easily
00:16:28 --> 00:16:30 make black holes and well one of the
00:16:30 --> 00:16:32 challenges in in globular classes has
00:16:32 --> 00:16:33 been to look for these intermediate Mass
00:16:33 --> 00:16:35 black holes with you know some evidence
00:16:35 --> 00:16:37 that they seem do seem to be there they
00:16:37 --> 00:16:39 just found in aega centur didn't they
00:16:39 --> 00:16:40 yeah I think it was certainly claims
00:16:40 --> 00:16:42 that intermediate my black holes in
00:16:42 --> 00:16:44 these nearby go clusters well there
00:16:44 --> 00:16:46 something like 150 of the moring our
00:16:46 --> 00:16:48 galaxy so there's plenty to choose from
00:16:48 --> 00:16:49 so the thing about the go clusters is
00:16:49 --> 00:16:51 they're really old so that they're
00:16:51 --> 00:16:52 they're what we call low metallicity
00:16:52 --> 00:16:54 Stars so that's stars without lots of
00:16:54 --> 00:16:56 hydrogen helium and not many of the
00:16:56 --> 00:16:58 heavier elements and those we think come
00:16:58 --> 00:17:00 from the very real universe so for
00:17:00 --> 00:17:01 example dating some of those globular
00:17:01 --> 00:17:03 clusters we think some of them are maybe
00:17:03 --> 00:17:05 up to 12 billion years old in fact there
00:17:05 --> 00:17:06 was an old problem that they were
00:17:06 --> 00:17:08 actually older than the universe itself
00:17:08 --> 00:17:09 which was a bit of an issue but people
00:17:09 --> 00:17:11 fixed that with better distance
00:17:11 --> 00:17:12 estimates and it seemed to all match up
00:17:12 --> 00:17:13 again but you know they are sort of
00:17:14 --> 00:17:15 remnants from that early stage of the
00:17:15 --> 00:17:17 universe where we think probably things
00:17:17 --> 00:17:18 were a bit more violent and a bit more
00:17:18 --> 00:17:20 you know was a bit easier to form these
00:17:20 --> 00:17:22 very Dense Star clusters for example
00:17:22 --> 00:17:25 that's Professor Daniel price from Mones
00:17:25 --> 00:17:29 University and this SpaceTime still to
00:17:29 --> 00:17:31 come New Revelations about the
00:17:31 --> 00:17:33 composition of the Earth's mantle and
00:17:33 --> 00:17:35 the discovery that water is actually
00:17:35 --> 00:17:38 fairly widespread across the surface of
00:17:38 --> 00:17:40 the Moon you just got to know where to
00:17:40 --> 00:17:43 look all that and more still to come on
00:17:43 --> 00:17:48 SpaceTime
00:17:48 --> 00:17:57 [Music]
00:18:00 --> 00:18:01 well it looks like it's time to rewrite
00:18:01 --> 00:18:04 the geological textbooks of the planet a
00:18:04 --> 00:18:06 new study has found that the chemical
00:18:06 --> 00:18:08 composition of the Earth's mantle is
00:18:08 --> 00:18:10 basically the same everywhere and only
00:18:10 --> 00:18:13 changes into unique compositions as it
00:18:13 --> 00:18:15 passes through different layers of crust
00:18:15 --> 00:18:17 closer to the planet's surface the new
00:18:17 --> 00:18:19 findings reported in the journal Nature
00:18:19 --> 00:18:22 GS science are based on an evaluation of
00:18:22 --> 00:18:25 volcanic hotspots around the globe it
00:18:25 --> 00:18:27 shows that lavas from hotpots whether
00:18:27 --> 00:18:30 erupting in Hawaii Samoa or Iceland
00:18:30 --> 00:18:32 likely all originate from what appears
00:18:32 --> 00:18:35 to be a worldwide uniform Reservoir in
00:18:35 --> 00:18:37 the Earth's mantle it means the Earth's
00:18:37 --> 00:18:40 metal is far more chemically homogeneous
00:18:40 --> 00:18:42 than scientists previously thought one
00:18:42 --> 00:18:44 of the study's authors matiah Schmid
00:18:44 --> 00:18:46 from the University of British Columbia
00:18:46 --> 00:18:49 says the discovery quite literally turn
00:18:49 --> 00:18:51 science's view of Hots spot lavas in the
00:18:51 --> 00:18:55 mantle upside down he says in a way the
00:18:55 --> 00:18:57 Earth's lavas are much like the human
00:18:57 --> 00:19:00 race a beautifully Dev population with a
00:19:00 --> 00:19:02 common ancestor but which developed
00:19:02 --> 00:19:04 differently wherever it went of course
00:19:04 --> 00:19:06 Research into Earth's Metals always been
00:19:06 --> 00:19:08 Complicated by the simple fact that it
00:19:08 --> 00:19:11 can't be sampled directly so instead
00:19:11 --> 00:19:13 researchers need to engage in a bit of
00:19:13 --> 00:19:16 GE scientific detective work they study
00:19:16 --> 00:19:18 this important part of the planet
00:19:18 --> 00:19:20 through Trace element isotopic analysis
00:19:20 --> 00:19:22 of the lavas that come from the mantle
00:19:22 --> 00:19:24 and which is erupted at oceanic
00:19:24 --> 00:19:27 volcanoes around the world the vast
00:19:27 --> 00:19:29 differences in composition in in these
00:19:29 --> 00:19:31 lavas along with the assumption that the
00:19:31 --> 00:19:33 isotopic composition of magma doesn't
00:19:33 --> 00:19:34 change between its source and the
00:19:34 --> 00:19:37 surface has wrongly led to a general
00:19:37 --> 00:19:39 view that Metals contain distinct
00:19:39 --> 00:19:41 reservoirs of different ages located in
00:19:41 --> 00:19:43 different regions and formed by
00:19:43 --> 00:19:46 different processes the observations
00:19:46 --> 00:19:48 made by Schmidt and colleagues however
00:19:48 --> 00:19:50 indicate the reality could be quite
00:19:50 --> 00:19:52 different Schmidt says by looking at a
00:19:52 --> 00:19:55 specific set of elements scientists were
00:19:55 --> 00:19:57 able to discern chemical effects of
00:19:57 --> 00:19:59 various processes that act on magma
00:19:59 --> 00:20:01 melts on their way to the surface and
00:20:01 --> 00:20:03 this allowed them to discover that all
00:20:03 --> 00:20:05 hotspot livas actually share the same
00:20:06 --> 00:20:08 starting composition that means the
00:20:08 --> 00:20:10 lavas only come out differently on the
00:20:10 --> 00:20:12 surface because the magmas are
00:20:12 --> 00:20:14 interacting with different geology as
00:20:14 --> 00:20:16 they ascend up through the crust the
00:20:16 --> 00:20:19 Earth's metal is a seething layer of
00:20:19 --> 00:20:21 molten and semi- molten material
00:20:21 --> 00:20:23 comprising about 84% of the planet's
00:20:23 --> 00:20:25 volume lying between the Earth's liquid
00:20:25 --> 00:20:28 iron outer core and its thin surface
00:20:28 --> 00:20:30 crust when magma derived from the mantle
00:20:30 --> 00:20:32 penetrates the crust and erupts onto the
00:20:32 --> 00:20:35 surface it's called lava knowing what
00:20:35 --> 00:20:37 the mantle is made of is Central to
00:20:37 --> 00:20:39 science's understanding of how the
00:20:39 --> 00:20:41 planet formed and how the mantle itself
00:20:41 --> 00:20:44 developed and evolved over time it may
00:20:44 --> 00:20:46 also provide clues as to why the metal
00:20:46 --> 00:20:49 behaves the way it does how it drives
00:20:49 --> 00:20:52 plate tectonics and what its role is in
00:20:52 --> 00:20:54 the global cycle of elements despite
00:20:54 --> 00:20:56 shedding entirely new light on Hotspot
00:20:56 --> 00:20:58 lavas in Oceanic parts of the world the
00:20:58 --> 00:21:00 analysis also reveals an exciting New
00:21:01 --> 00:21:04 link to ptic lavas on the continents
00:21:04 --> 00:21:06 these Ms which contain Diamond bearing
00:21:06 --> 00:21:08 kimberlites are fundamentally different
00:21:08 --> 00:21:11 from magmas found at Oceanic hotpots but
00:21:11 --> 00:21:13 they nevertheless still have the same
00:21:13 --> 00:21:16 magma ancestor this discovery really is
00:21:16 --> 00:21:18 a GameChanger when it comes to models of
00:21:18 --> 00:21:20 Earth's chemical Evolution and how
00:21:20 --> 00:21:23 science looks at Global Elemental Cycles
00:21:23 --> 00:21:25 not only is the mantle much more
00:21:25 --> 00:21:27 homogeneous than previously thought it
00:21:27 --> 00:21:29 likely also no longer contains
00:21:29 --> 00:21:32 primordial reservoirs these were
00:21:32 --> 00:21:34 entities that were once thought to exist
00:21:34 --> 00:21:36 and were needed to explain the data
00:21:36 --> 00:21:38 scientists were seeing trouble is the
00:21:38 --> 00:21:40 hypothesis of these things could never
00:21:40 --> 00:21:42 really be reconciled with the very
00:21:42 --> 00:21:45 concept of mantal convection and so now
00:21:45 --> 00:21:47 thanks to this new study we can dismiss
00:21:47 --> 00:21:51 it completely this is spacetime still to
00:21:51 --> 00:21:53 come scientists discover there are far
00:21:53 --> 00:21:55 more widespread water resources on the
00:21:55 --> 00:21:57 moon than previously thought you've just
00:21:57 --> 00:21:59 got to know where to look and later in
00:21:59 --> 00:22:01 the science report a new study finally
00:22:01 --> 00:22:04 pins down where the Australian wild dog
00:22:04 --> 00:22:07 the dingo really originated from all
00:22:07 --> 00:22:14 that and more still to come on
00:22:14 --> 00:22:24 [Music]
00:22:24 --> 00:22:27 SpaceTime a new analysis of maps from
00:22:27 --> 00:22:29 both the near and far sides of the Moon
00:22:29 --> 00:22:31 a showing scientist that the lunar
00:22:31 --> 00:22:34 surface contains vast amounts of water
00:22:34 --> 00:22:36 trouble is it's mostly locked in the
00:22:36 --> 00:22:39 lunar regolith the findings reported in
00:22:39 --> 00:22:41 the planetary science journal suggest
00:22:41 --> 00:22:42 that there are multiple sources of water
00:22:42 --> 00:22:45 and hydroxy in sunlet rocks and soils
00:22:45 --> 00:22:47 including water-rich rocks excavated by
00:22:47 --> 00:22:51 meteor impacts at all lunar latitudes by
00:22:51 --> 00:22:53 the way hydroxy are functional chemical
00:22:53 --> 00:22:56 groups of molecules comprising a single
00:22:56 --> 00:22:58 hydrogen and a single oxygen atom but
00:22:58 --> 00:23:01 missing the second hydrogen atom needed
00:23:01 --> 00:23:03 to turn it into a water molecule see the
00:23:03 --> 00:23:05 solar wind carries normal hydrogen atoms
00:23:05 --> 00:23:08 to the Moon where the molecules interact
00:23:08 --> 00:23:10 with oxygen already on the surface to
00:23:10 --> 00:23:13 form both hydroxy and water the study's
00:23:13 --> 00:23:15 lead author Roger Clark from the
00:23:15 --> 00:23:17 planetary Science Institute says future
00:23:17 --> 00:23:18 astronauts should be able to find water
00:23:18 --> 00:23:20 even near the equator simply by
00:23:20 --> 00:23:23 exploiting these water rich areas
00:23:23 --> 00:23:24 previously it was thought that only
00:23:24 --> 00:23:27 lunar polar regions and in particular
00:23:27 --> 00:23:29 the deeply shattered crators at the
00:23:29 --> 00:23:30 poles where sunlight never reaches the
00:23:30 --> 00:23:33 crater floor were likely to contain
00:23:33 --> 00:23:36 abundant Water Supplies Frozen as ice
00:23:36 --> 00:23:38 Clark says knowing where the water is
00:23:38 --> 00:23:40 located not only helps scientists better
00:23:40 --> 00:23:42 understand lunar geologic history but
00:23:42 --> 00:23:45 also where astronauts may find water in
00:23:45 --> 00:23:47 the future that water could then be used
00:23:47 --> 00:23:49 for drinking or split up to be turned
00:23:49 --> 00:23:52 into rocket fuel or simply for breathing
00:23:52 --> 00:23:54 Clark and colleagues base their findings
00:23:54 --> 00:23:56 on data from the Moon minerology mapper
00:23:56 --> 00:23:59 Imaging spectrometer aboard the Indian
00:23:59 --> 00:24:01 chandran once spacecraft which orbited
00:24:01 --> 00:24:04 the moon during 2008 and 2009 mapping
00:24:04 --> 00:24:06 water and hydroxy on both the near and
00:24:06 --> 00:24:08 far sides of the Moon in far greater
00:24:08 --> 00:24:11 detail than it ever been done before the
00:24:11 --> 00:24:14 mapa used infrared spectroscopy to
00:24:14 --> 00:24:15 search with the Fingerprints of both
00:24:15 --> 00:24:17 water and hydroxy in the Spectra of
00:24:17 --> 00:24:20 reflected sunlight on the lunar surface
00:24:20 --> 00:24:22 while a digital camera records three
00:24:23 --> 00:24:24 colors in the visible part of the
00:24:24 --> 00:24:26 electromagnetic spectrum the mapper
00:24:26 --> 00:24:28 instrument recorded 85 colors in the
00:24:28 --> 00:24:31 visible spectrum and also well into the
00:24:31 --> 00:24:33 infrared just like we see different
00:24:33 --> 00:24:34 colors from different materials the
00:24:35 --> 00:24:36 infrared spectrometer can see many
00:24:36 --> 00:24:38 infrared colors to better determine the
00:24:39 --> 00:24:41 composition and that includes water and
00:24:41 --> 00:24:43 hydroxy the water may be directly
00:24:43 --> 00:24:46 harvested by heating rocks and soils the
00:24:46 --> 00:24:48 water can also be formed by chemical
00:24:48 --> 00:24:51 reactions liberating hydroxy and
00:24:51 --> 00:24:53 combining four Hydrox to create oxygen
00:24:53 --> 00:24:56 and Water by studying the location and
00:24:56 --> 00:24:58 geologic context the authors were able
00:24:59 --> 00:25:01 to show that water in the lunar surface
00:25:01 --> 00:25:03 is metastable meaning H2O is slowly
00:25:03 --> 00:25:06 destroyed over millions of years but
00:25:06 --> 00:25:09 with hydroxy the O remaining also a
00:25:10 --> 00:25:12 cratering event that exposes subsurface
00:25:12 --> 00:25:14 water Rich rocks to the solar wind will
00:25:14 --> 00:25:17 also degrade with time destroying H2O
00:25:17 --> 00:25:21 and creating a diffuse Aura of hydroxy o
00:25:21 --> 00:25:23 but the destruction is slow taking
00:25:23 --> 00:25:25 thousands to millions of
00:25:25 --> 00:25:27 years Elsewhere on the lunar surface
00:25:27 --> 00:25:29 there appears to be a petiner of hydroxy
00:25:30 --> 00:25:32 probably created by solar wind protons
00:25:32 --> 00:25:34 impacting the lunar surface destroying
00:25:34 --> 00:25:36 silic minerals where the protons combine
00:25:36 --> 00:25:38 with oxygen in the silicates in order to
00:25:38 --> 00:25:42 create hydroxy in a process called space
00:25:42 --> 00:25:44 weathering putting all the evidence
00:25:44 --> 00:25:46 together Clark and colleagues see a Luna
00:25:46 --> 00:25:48 surface with complex geology with
00:25:49 --> 00:25:51 significant water in the subsurface and
00:25:51 --> 00:25:53 a surface layer of hydroxy both
00:25:53 --> 00:25:56 cratering and volcanic activity can
00:25:56 --> 00:25:57 bring water-rich materials to the
00:25:57 --> 00:26:00 surface and both are observed in the
00:26:00 --> 00:26:01 lunar
00:26:01 --> 00:26:04 data our moon is made up primarily of
00:26:04 --> 00:26:07 two kinds of rocks there's the Dark Mari
00:26:07 --> 00:26:09 we see from the earth which gives us the
00:26:09 --> 00:26:12 Man in the Moon image this is basically
00:26:12 --> 00:26:15 Baltic Rock like solidified lava then
00:26:15 --> 00:26:17 there's the andesitic Rocks which are
00:26:17 --> 00:26:20 lighter and found in the lunar Highlands
00:26:20 --> 00:26:22 it's the andesites which contain lots of
00:26:22 --> 00:26:24 water while the basalts contain very
00:26:24 --> 00:26:27 little the study also sheds new light on
00:26:27 --> 00:26:30 previous ly known Mysteries when the
00:26:30 --> 00:26:32 sunlight is shining on the lunar surface
00:26:32 --> 00:26:34 at different times of the day the
00:26:34 --> 00:26:36 strength of water and hydroxy
00:26:36 --> 00:26:38 absorptions change that led to the
00:26:38 --> 00:26:40 calculation that a lot of the water and
00:26:40 --> 00:26:42 hydroxy had to be moving around the Moon
00:26:42 --> 00:26:45 on a daily cycle however this new study
00:26:45 --> 00:26:47 showed that very stable mineral
00:26:47 --> 00:26:49 absorptions of water and hydroxy show
00:26:49 --> 00:26:52 the same daily effect but on minerals
00:26:52 --> 00:26:55 like pyxine a common ous silicate
00:26:55 --> 00:26:57 material on the lunar surface they don't
00:26:57 --> 00:26:58 evaporate at lunar tempature
00:26:58 --> 00:27:00 temperatures the reason for this effect
00:27:00 --> 00:27:02 is instead due to a thin layer of
00:27:02 --> 00:27:04 enriched composition and or so particle
00:27:04 --> 00:27:06 size that's different from deeper down
00:27:06 --> 00:27:09 in the soil so when the sun is low in
00:27:09 --> 00:27:11 the lunar Sky light transmits through
00:27:11 --> 00:27:14 more of this top layer strengthening the
00:27:14 --> 00:27:15 infrared absorptions compared to when
00:27:15 --> 00:27:18 the sun is higher in the sky now don't
00:27:18 --> 00:27:19 get me wrong there may still be water
00:27:19 --> 00:27:22 moving around but to know how much new
00:27:22 --> 00:27:24 studies will be needed to quantify the
00:27:24 --> 00:27:27 layering effects also if you recall the
00:27:27 --> 00:27:29 lunar Ro tracks appear to be darker in
00:27:29 --> 00:27:32 images from the Apollo era Rovers that's
00:27:32 --> 00:27:34 another indicator that the surface layer
00:27:34 --> 00:27:37 is thin and very different related to
00:27:37 --> 00:27:39 this thin surface layer are the
00:27:39 --> 00:27:41 expressions of enigmatic features on the
00:27:41 --> 00:27:44 Moon called lunar swirls these are
00:27:44 --> 00:27:46 diffuse patterns invisible light in
00:27:46 --> 00:27:48 several areas in the moon now it's
00:27:48 --> 00:27:50 magnetic fields which are thought to
00:27:50 --> 00:27:52 play a role in swirl formation by
00:27:52 --> 00:27:54 diverting solar wind which would also
00:27:54 --> 00:27:56 reduce hydroxy production and that
00:27:57 --> 00:27:58 matches up with earlier studies which
00:27:58 --> 00:28:01 show that lunar SRS are deficient in
00:28:01 --> 00:28:04 hydroxy the new study confirms this but
00:28:04 --> 00:28:06 also shows more complexity that is the
00:28:06 --> 00:28:09 swirls are also low in water content but
00:28:09 --> 00:28:12 is sometimes higher in pyxine content
00:28:12 --> 00:28:14 this new study using lunar Global
00:28:14 --> 00:28:16 hydroxy Maps also shows neverbe seen
00:28:16 --> 00:28:19 areas that are similar to n swirls but
00:28:19 --> 00:28:21 have no diffuse patterns seen inv
00:28:21 --> 00:28:23 visible light thus can only be seen in
00:28:23 --> 00:28:26 hydroxy absorption these new features
00:28:26 --> 00:28:28 May in fact be old eroded Swirls and
00:28:28 --> 00:28:31 include new types including arcs and
00:28:31 --> 00:28:33 linear features by mapping the moon in
00:28:33 --> 00:28:35 new ways like this the Luna surface is
00:28:35 --> 00:28:38 showing scientists that it's far more
00:28:38 --> 00:28:41 complex than previously thought good to
00:28:41 --> 00:28:44 know as we move closer to the emus 3
00:28:44 --> 00:28:47 mission in 2026 and man's return to the
00:28:47 --> 00:28:48 lunar
00:28:48 --> 00:28:53 surface this is spacetime
00:28:53 --> 00:29:06 [Music]
00:29:06 --> 00:29:08 and time now to take a brief look at
00:29:08 --> 00:29:10 some of the other stories making news in
00:29:10 --> 00:29:12 science this week with the science
00:29:12 --> 00:29:15 report new climate models are warning
00:29:15 --> 00:29:17 that future droughts could be even worse
00:29:17 --> 00:29:19 than previously thought a report in the
00:29:19 --> 00:29:22 journal Nature claims scius calibrated
00:29:22 --> 00:29:24 models with historical observations of
00:29:24 --> 00:29:26 the longest annual dry spells that is
00:29:26 --> 00:29:29 the longest number of cons Ive dry days
00:29:29 --> 00:29:32 each year between 1998 and
00:29:32 --> 00:29:34 2018 they found the average longest
00:29:34 --> 00:29:37 period of drought could end up being 10
00:29:37 --> 00:29:38 days longer by the end of the century
00:29:39 --> 00:29:41 than previously predicted the authors
00:29:41 --> 00:29:43 say the findings emphasize the need for
00:29:43 --> 00:29:45 a reassessment of drought risks around
00:29:45 --> 00:29:47 the world and they highlight the
00:29:47 --> 00:29:49 importance of correcting existing biases
00:29:49 --> 00:29:52 in climate models to increase confidence
00:29:52 --> 00:29:53 in their
00:29:53 --> 00:29:56 projections a new study claims just
00:29:56 --> 00:29:59 taking 3 minutes of exercise every half
00:29:59 --> 00:30:01 hour in the evenings could help you
00:30:01 --> 00:30:03 sleep the findings reported in the
00:30:03 --> 00:30:05 British medical journal based on a small
00:30:05 --> 00:30:07 study investigating how exercise later
00:30:07 --> 00:30:10 in the day could impact on sleep the
00:30:10 --> 00:30:12 authors recruited 28 people to wear
00:30:12 --> 00:30:14 trackers and then monitored their
00:30:14 --> 00:30:16 activity and sleep on two days about a
00:30:16 --> 00:30:18 week apart they were each asked to spend
00:30:18 --> 00:30:21 4 hours in the lab from around 5:00 p.m.
00:30:21 --> 00:30:23 in the afternoon in one of these
00:30:23 --> 00:30:25 sessions the participants sat for an
00:30:25 --> 00:30:28 entire 4 hours while in the other they
00:30:28 --> 00:30:30 completed an equipment free 3 minute
00:30:30 --> 00:30:32 resistance exercise program every half
00:30:32 --> 00:30:35 hour the authors found that the
00:30:35 --> 00:30:37 participant slept for an average of 27
00:30:37 --> 00:30:38 minutes longer after they did the
00:30:38 --> 00:30:41 exercise program session compared to the
00:30:41 --> 00:30:43 simply sitting around session with no
00:30:43 --> 00:30:45 differences in Sleep
00:30:46 --> 00:30:48 Quality new archaeological researchers
00:30:48 --> 00:30:50 discovered clear links between fossils
00:30:51 --> 00:30:53 of the iconic Australian Native dog the
00:30:53 --> 00:30:55 dingo and dogs from East Asia and Papa
00:30:55 --> 00:30:58 New Guinea the findings published in the
00:30:58 --> 00:31:00 journal scientific reports suggest that
00:31:00 --> 00:31:02 the dingo must have come from East Asia
00:31:02 --> 00:31:05 via melanesia and it challenges previous
00:31:05 --> 00:31:07 hypotheses that the dogs arrived from
00:31:07 --> 00:31:10 India or Thailand previous studies had
00:31:10 --> 00:31:13 used traditional morphometric analysis
00:31:13 --> 00:31:15 this looks at the size and shape of the
00:31:15 --> 00:31:17 animal using calipers in order to trace
00:31:17 --> 00:31:20 the dingo's ancestry to South Asia
00:31:20 --> 00:31:22 however the new study used more
00:31:22 --> 00:31:24 sophisticated 3D scanning techniques
00:31:24 --> 00:31:26 combined with geometric morphometrics on
00:31:26 --> 00:31:29 Ancient dingo spe to clearly show that
00:31:29 --> 00:31:31 they're really most similar to Japanese
00:31:31 --> 00:31:34 dogs as well as the singing dogs of Papa
00:31:34 --> 00:31:36 New Guinea and the Highland wild dogs of
00:31:36 --> 00:31:39 Iran G the authors also found that
00:31:39 --> 00:31:41 modern day dingos have evolved to become
00:31:41 --> 00:31:43 larger and leaner standing an average of
00:31:43 --> 00:31:47 54 cm tall compared to between 40 and 47
00:31:47 --> 00:31:50 CM for their ancient ancestors a size
00:31:50 --> 00:31:52 which is also much closer to their
00:31:52 --> 00:31:54 contemporary relatives in Southeast Asia
00:31:54 --> 00:31:56 and
00:31:56 --> 00:31:58 melanesia well it seems latest fat in
00:31:58 --> 00:32:00 Japan and the United States for the
00:32:00 --> 00:32:02 paranormally inclined is what they're
00:32:02 --> 00:32:05 calling a ghost detecting Stone it's
00:32:05 --> 00:32:08 claim that this Stone changes color when
00:32:08 --> 00:32:10 ghosts Angels or evil spirits are
00:32:10 --> 00:32:12 lurking about now of course the first
00:32:12 --> 00:32:14 problem is we're assuming that ghosts
00:32:14 --> 00:32:17 angels and evil spirits are real you've
00:32:17 --> 00:32:18 also got the problem that it's not
00:32:19 --> 00:32:20 really a stone it's just a chunk of
00:32:20 --> 00:32:22 plastic with some electronics and the
00:32:22 --> 00:32:25 battery inside and at 100 bucks in oy
00:32:25 --> 00:32:29 dollars it ain't cheap so does it work
00:32:29 --> 00:32:30 well I guess it depends on whether or
00:32:30 --> 00:32:33 not you want to believe as Tim mendum
00:32:33 --> 00:32:36 from Australian Skeptics explains it's
00:32:36 --> 00:32:38 weird it's little Stones about the size
00:32:38 --> 00:32:40 of a couple of centimeters across yeah
00:32:40 --> 00:32:41 round about that size that supposedly
00:32:41 --> 00:32:43 changeed color when they're surrounded
00:32:43 --> 00:32:45 by some sort of Paranormal Activity they
00:32:45 --> 00:32:48 sell for about $60 odd dollars US which
00:32:48 --> 00:32:50 in Australian money is about $100 how
00:32:50 --> 00:32:51 they're not cheap but they supposedly
00:32:51 --> 00:32:53 change color and they glow they glow
00:32:53 --> 00:32:56 green during unusual Paranormal Activity
00:32:56 --> 00:32:58 they glow blue when there's an Angelic
00:32:58 --> 00:33:00 presence and they glow red when a ghost
00:33:00 --> 00:33:02 is nearby so I'm not quite sure what the
00:33:02 --> 00:33:03 Paranormal Activity is compared to a
00:33:03 --> 00:33:05 ghost or an angel anyway they go through
00:33:05 --> 00:33:08 these three colors and basically it's a
00:33:08 --> 00:33:10 search mode which is activated manually
00:33:10 --> 00:33:11 it's hard to tell by the pictures I
00:33:11 --> 00:33:13 don't own one I should and no one apart
00:33:14 --> 00:33:16 from the manufacturer exactly sure how
00:33:16 --> 00:33:17 they work probably if you try to take
00:33:17 --> 00:33:19 them apart they are plastic so they're
00:33:20 --> 00:33:21 not real Stones H they're not real
00:33:21 --> 00:33:23 Stones they have a sensor so they
00:33:23 --> 00:33:24 obviously have a chip inside of some
00:33:24 --> 00:33:26 sort and they sort of do various things
00:33:26 --> 00:33:28 there's a search mode which you scans
00:33:28 --> 00:33:30 around there's an automatic mode which
00:33:30 --> 00:33:32 automatically scans the environments
00:33:32 --> 00:33:33 every 10 minutes and there's a barrier
00:33:33 --> 00:33:35 mode which is designed to block
00:33:35 --> 00:33:37 dangerous Spirits from harming the user
00:33:37 --> 00:33:39 now I don't think they're exactly the
00:33:39 --> 00:33:40 same as what we used to called mood
00:33:40 --> 00:33:42 rings which were the Liquid Crystal
00:33:42 --> 00:33:43 things that you heated it up and they
00:33:43 --> 00:33:45 change because of the change of
00:33:45 --> 00:33:46 temperature they change color supposed
00:33:46 --> 00:33:49 to indicate your passion level it's a
00:33:49 --> 00:33:52 Japanese thing it's called batan REI
00:33:52 --> 00:33:54 which means a stone that searches for
00:33:54 --> 00:33:55 ghosts not particularly the most
00:33:55 --> 00:33:58 exciting name but yeah and it has a
00:33:58 --> 00:34:00 crystal ball perhaps inside it and it's
00:34:00 --> 00:34:02 made of ABS thermoplastic so it's not a
00:34:02 --> 00:34:04 real Stone does it tell you about the
00:34:04 --> 00:34:06 sort of people who buy this sort of
00:34:06 --> 00:34:08 thing I mean a lot of people will buy it
00:34:08 --> 00:34:10 for the novity value sure but there are
00:34:10 --> 00:34:12 going to be a lot of people out there
00:34:12 --> 00:34:15 who are going to buy it because they're
00:34:15 --> 00:34:16 serious they think it's going to help
00:34:16 --> 00:34:17 them there will be there's a lot of
00:34:17 --> 00:34:19 people who use a lot of gadgets pick up
00:34:19 --> 00:34:20 radio signals that sort of thing ghostly
00:34:20 --> 00:34:23 signals Etc on their particular handheld
00:34:23 --> 00:34:25 device or it's an app on on a mobile
00:34:25 --> 00:34:26 phone something like that so this is
00:34:26 --> 00:34:27 supposed to be something that will give
00:34:27 --> 00:34:29 you an indication if there's something
00:34:29 --> 00:34:32 there so do these apps and and little
00:34:32 --> 00:34:34 portable devices do the same thing I
00:34:34 --> 00:34:37 don't think you can record the uh events
00:34:37 --> 00:34:39 is just an indicator whereas a handheld
00:34:39 --> 00:34:42 device or an app might record signals
00:34:42 --> 00:34:44 radio signals electronic voice signals
00:34:44 --> 00:34:46 that sort of thing elic voice patents
00:34:46 --> 00:34:48 sorry that sort of stuff so is it a
00:34:48 --> 00:34:50 substitute no now this is assuming it
00:34:50 --> 00:34:52 works then I'm not going to assume that
00:34:52 --> 00:34:53 by a long way you have to have more than
00:34:53 --> 00:34:55 a passing interest you'll use it once or
00:34:55 --> 00:34:56 twice and then it'll go in the in the
00:34:56 --> 00:34:58 draw prob there forever you pull that
00:34:58 --> 00:35:00 after while say what's this but there
00:35:00 --> 00:35:03 are alternatives I don't think serious
00:35:03 --> 00:35:06 Ghost Hunters would use it very much
00:35:06 --> 00:35:08 people having fun people doing a weder
00:35:08 --> 00:35:09 board say after the middle of the night
00:35:09 --> 00:35:11 having a fun and a few drinks might put
00:35:11 --> 00:35:13 it down to see find some
00:35:13 --> 00:35:16 Spirits boom it will that's Tim mendum
00:35:16 --> 00:35:19 from Australian Skeptics
00:35:19 --> 00:35:28 [Music]
00:35:33 --> 00:35:36 and that's the show for now SpaceTime is
00:35:36 --> 00:35:38 available every Monday Wednesday and
00:35:38 --> 00:35:41 Friday through Apple podcasts iTunes
00:35:41 --> 00:35:43 Stitcher Google podcast pocketcasts
00:35:44 --> 00:35:48 Spotify acast Amazon music bites.com
00:35:48 --> 00:35:50 SoundCloud YouTube your favorite podcast
00:35:50 --> 00:35:53 download provider and from SpaceTime
00:35:53 --> 00:35:56 with Stewart gary.com space time's also
00:35:56 --> 00:35:57 broadcast through the national Science
00:35:58 --> 00:36:00 Foundation on science Z Radio and on
00:36:00 --> 00:36:03 both iHeart radio and TuneIn radio and
00:36:03 --> 00:36:05 you can help to support our show by
00:36:05 --> 00:36:07 visiting the SpaceTime store for a range
00:36:07 --> 00:36:10 of promotional merchandising goodies or
00:36:10 --> 00:36:12 by becoming A Spacetime Patron which
00:36:12 --> 00:36:14 gives you access to Triple episode
00:36:14 --> 00:36:16 commercial free versions of the show as
00:36:16 --> 00:36:17 well as lots of burnus audio content
00:36:18 --> 00:36:20 which doesn't go to air access to our
00:36:20 --> 00:36:22 exclusive Facebook group and other
00:36:22 --> 00:36:24 Awards just go to SpaceTime withth
00:36:24 --> 00:36:27 Stewart gary.com for full details and if
00:36:27 --> 00:36:29 you want more SpaceTime please check out
00:36:29 --> 00:36:31 our blog where you'll find all the stuff
00:36:31 --> 00:36:33 we couldn't fit in the show as well as
00:36:33 --> 00:36:35 heaps of images news stories loads of
00:36:35 --> 00:36:37 videos and things on the web I find
00:36:37 --> 00:36:39 interesting or amusing just go to
00:36:39 --> 00:36:42 SpaceTime with Stewart gary. tumblr.com
00:36:42 --> 00:36:45 that's all one word and that's Tumblr
00:36:45 --> 00:36:47 without the e you can also follow us
00:36:47 --> 00:36:50 through @ Stewart Gary on Twitter at
00:36:50 --> 00:36:52 SpaceTime with Stewart Gary on Instagram
00:36:52 --> 00:36:55 through our SpaceTime YouTube channel
00:36:55 --> 00:36:57 and on Facebook just go to facebook.com
00:36:57 --> 00:37:01 /s SpaceTime with Stewart Gary you've
00:37:01 --> 00:37:03 been listening to SpaceTime with Stewart
00:37:03 --> 00:37:05 Gary this has been another quality
00:37:05 --> 00:37:09 podcast production from bites.com