Ancient Impacts, Lunar Ice Potential, and the Return of X37B: S28E33

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Language: en

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this is Spacetime Series 28 episode 33


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for broadcast on the 17th of March


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2025 Coming up on Spaceime the world's


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oldest meteor impact crater discovered


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in Western Australia More potential


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locations for water ice on the moon and


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the super secret X37b space shuttle


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returns to Earth following its latest


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mission All that and more coming up on


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Spaceime


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Welcome to SpaceTime with Stuart


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Garry Scientists have uncovered what is


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now the world's oldest known meteor


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impact crater in Western Australia


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Remnants of the ancient 3 and a half


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billiony old structure were discovered


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in the north pole derm region of the


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Pilbur in the state's north The previous


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oldest known impact crater also in


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Western Australia was dated at 2.2


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billion years The new discovery reported


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in the journal Nature Communications


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could significantly redefine science's


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understanding of the origins of life and


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how the planet was formed and evolved


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One of the study's authors Tim Johnson


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from Curtain University says the


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structure challenges previous


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assumptions about Earth's ancient


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history Johnson and colleagues


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discovered the crater thanks to shatter


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cones distinctive rock formations that


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only form under the intense pressure of


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a meteor strike The shatter cones at the


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site about 40 km west of Marble Bar were


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formed when a meteor slammed into the


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area at more than 36,000 kmh


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Johnson says this impact would have been


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a major planetary event resulting in a


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crater more than 100 kilometers across


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which would have sent ejected debris


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high into the atmosphere eventually


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raining back down across the entire


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planet He says the face of the moon is


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proof that large impacts were common in


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the early history of the solar system


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But until now the absence of any truly


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ancient impact craters on Earth has


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meant they're largely ignored by


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geologists Johnson says this study


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provides a crucial piece of the puzzle


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of Earth's impact history and suggested


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there could be many more ancient craters


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yet to be discovered Uncovering this


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impact structure and finding more from


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the same period could also help explain


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how life began on Earth That's because


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impact craters generate environments


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friendly to microbial life such as hot


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water pools full of mineral nutrients


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Johnson says it also radically


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redefineses science's understanding of


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crust formation You see the tremendous


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amount of energy from this impact could


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have played a major role in shaping the


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Earth's early crust It does this by


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pushing one part of the crust under


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another or by forcing magma to rise from


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deep within the Earth's mantle up


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towards the surface It may even have


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contributed to the formation of large


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ancient geological structures stretching


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deep down into the planet that may well


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be the foundations of today's continents


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So in 2022 we published a paper in


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Nature suggesting that the Pilra caton


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ultimately may have formed above one of


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these giant impacts of the type that we


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see on the on the surface of the moon


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Those dark Luna Mariah the Imbrium


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crater you know there was very big


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impacts that hit the moon There was very


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big impacts that hit the Earth And we


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believed as I say that the Pilocraton


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could have been a consequence of these


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And we used at that time we found some


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evidence based on the chemical


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composition of these tiny sandsized


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grains of the mineral zirkon So zirkon


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is very very robust chemically and


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physically robust It also contains lots


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of radioactive uranium which decays over


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time for lead So we can date it and its


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host rocks very very accurately And we


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can also measure various trace elements


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and isotopes of oxygen and hapneium and


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other sorts of things in these zirkon


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grains to say something about how they


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might have formed and the processes Now


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that is all a bit esoteric and it's all


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sort of microscopic or nanocale science


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So it's very difficult for anybody to


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get their heads around really and I


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don't think very many if any people


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really believed that paper So we thought


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we would go up to the Pilra and try and


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look for some more macroscopic evidence


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if you like Could we find the crater or


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the crater a floor and we simply started


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our search right in the middle of the


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exposure of the most ancient rocks So


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part of the Pilraaton the most ancient


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core of it is called the east Pilra


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terrain and that is a curiously round


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set of exposures of rocks about 200 km


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across And in the middle of that is a


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structure called the North Pole Dome So


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we headed there and in particular to


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find this unusual layer called the


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Antarctic Creek member We were looking


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for that because that layer people had


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formerly found sper So sparials are


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quite simply the frozen droplets of melt


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that forms as a direct effect of the


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heat of the impact But they can also


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form as the result of volcanic eruptions


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But at least this layer had some


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evidence for a distal impact So we


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thought we would start there And we


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parked our four-wheel drives just off a


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dusty truck heading south from the main


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road where we thought these rocks might


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appear Three of us got out and had a


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wander around and we agreed to meet back


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at the vehicles an hour or so later And


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we found when we did meet back we


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thought we'd all found the same thing


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which is this feature called shatter


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cones in the rock And shatter cones are


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the only unequivocal evidence that you


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can see with a naked eye for a direct


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meteorite impact crater So shatter cones


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are known almost exclusively from what


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are called the central uplift of big


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craters So much like when you drop into


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water that drop hits the surface and


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then you have a rebound the drop comes


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back up Um that's exactly what happens


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with big craters So the impactor hits


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and then the center where you've had the


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maximum impact force rebounds and you


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get something called a central uplet And


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that's what we believe this whole big 20


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or 30 km wide dome in the middle of the


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East Pilra is And we found the evidence


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supporting that which was extremely


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lucky but very nice The Zirkons then


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gave you the date for that Yes So this


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layer Antarctic creek member it is


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called it's a very unusual very complex


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layer a whole mish mash of lots of


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different things including broken up


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bits of bassalt and shirts and these


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sperial layers and it's sitting in


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between a few kilometers of bassalt


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underneath it and a few kilometers of


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bassalt above it These shatter cones are


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developed right the way throughout this


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20 m or so thick layer called the


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Antarctic creek member But immediately


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above them are these beautiful pillow


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lavas So like giant toothpaste sort of


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squirted out which tell us that they


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were erupted underwater But there is no


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sign of shock at all in those rocks


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above And we traced them up for several


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tens of meters to try and look for


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shatter cones above where we found them


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and couldn't find any The Antarctic


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Creek member is also overlaining by


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these really complex carbonate breers


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that penetrate into it as dikes and big


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fractures So what we think we're looking


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at is the surface of the crater We're


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actually standing on the crater floors


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in this huge structure which is the


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central uplift of the crater So because


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we didn't find any shatter cones above


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we think the stratographic age of that


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layer the Antarctic creek member gives


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you the age of the impact and


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fortunately the geocchronologists of the


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geological society of Western Australia


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had already dated the rocks and there is


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a layer of felicit volcanic rocks below


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the shatter cone bearing horizon which


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has been dated by uraniumled ziron to be


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3.47 47 billion years old And the


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bassalts above there is a layer of


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feltic volcanics in those as well which


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has also been dated at 3.47 billion


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years old So that provides us with a


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stratographic age of 3.47 for the um


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shatter cone bearing horizon So we knew


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we had our age and we had our oldest


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impact breaker This discovery is really


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exciting because we know Earth was


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formed as a result of meteor and


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asteroid impacts It's called accretion


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There was a big one about 4.5 billion


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years ago which we call thea the moon


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Yes So we know this happens but there's


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also a thing with the earth called plate


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tectonics and also we have erosion and


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things like this So the early earth's


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history is something we know very little


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about This ancient impact must be


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telling us a lot about the history of


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our planet Absolutely Yes Yes I mean


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we've argued it's 2018 really where we


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first got into this that large impacts


00:09:07.040 --> 00:09:09.590
were absolutely fundamental to earth's


00:09:09.600 --> 00:09:12.070
early evolution as we can see they were


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on all the other silicate bodies in the


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unis solar system that we can see be


00:09:15.839 --> 00:09:18.230
they planets moons or asteroids as you


00:09:18.240 --> 00:09:20.550
say plate tectonics is an incredibly


00:09:20.560 --> 00:09:23.590
efficient way of recycling the surface


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the rigid surface of the earth the


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lithosphere and the crust back into the


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convecting mantle So most of the


00:09:29.680 --> 00:09:32.070
evidence is destroyed particularly given


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that most of the planet would have been


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oceanic and most of those impacts would


00:09:36.320 --> 00:09:38.070
have been into the ocean and and they've


00:09:38.080 --> 00:09:40.630
subsequently disappeared But we do have


00:09:40.640 --> 00:09:43.350
areas of really really truly ancient


00:09:43.360 --> 00:09:45.990
continental crust these so-called catons


00:09:46.000 --> 00:09:47.990
that occur in the middle of all of the


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continents and they started forming


00:09:50.959 --> 00:09:53.030
right at the tail end of what we know


00:09:53.040 --> 00:09:55.269
would have been an intense bombardment


00:09:55.279 --> 00:09:57.750
from the formation of the solar system 4


00:09:57.760 --> 00:10:00.070
1/2 billion years ago right up to 3 1/2


00:10:00.080 --> 00:10:02.230
billion years ago So we should be able


00:10:02.240 --> 00:10:04.710
to find evidence of these impacts and we


00:10:04.720 --> 00:10:06.870
think we do and we think they would have


00:10:06.880 --> 00:10:09.030
been fundamental to the processes


00:10:09.040 --> 00:10:11.670
operating then including how those


00:10:11.680 --> 00:10:14.389
catons might originally have come to be


00:10:14.399 --> 00:10:17.269
but also how for example the earliest


00:10:17.279 --> 00:10:18.630
mineral systems the earliest


00:10:18.640 --> 00:10:20.710
hydrothermal mineralization systems


00:10:20.720 --> 00:10:23.430
formed and perhaps even creating the


00:10:23.440 --> 00:10:25.829
ecological niches from which life


00:10:25.839 --> 00:10:27.829
eventually took a foothold and emerged


00:10:27.839 --> 00:10:30.630
to become us The catons themselves


00:10:30.640 --> 00:10:31.990
they're fascinating because they've


00:10:32.000 --> 00:10:33.990
given place like Western Australia where


00:10:34.000 --> 00:10:35.750
you are it's mineral wealth that's made


00:10:35.760 --> 00:10:37.829
at one of the richest places on earth


00:10:37.839 --> 00:10:40.630
quite literally Exactly So many of the


00:10:40.640 --> 00:10:43.110
mineral deposits things like gold and


00:10:43.120 --> 00:10:46.069
nickel and lithium even are found


00:10:46.079 --> 00:10:49.350
predominantly in these aranatons and at


00:10:49.360 --> 00:10:51.990
their margins and we don't think that is


00:10:52.000 --> 00:10:54.790
a coincidence So yes in incredibly


00:10:54.800 --> 00:10:56.790
important processes and incredibly


00:10:56.800 --> 00:10:59.110
important consequences for humankind I


00:10:59.120 --> 00:11:01.350
mean we argue that large impacts created


00:11:01.360 --> 00:11:03.829
the land masses on which all humankind


00:11:03.839 --> 00:11:06.470
walks and the life from which we evolve


00:11:06.480 --> 00:11:08.870
So they couldn't be more fundamental in


00:11:08.880 --> 00:11:11.590
our view The link between the cratons


00:11:11.600 --> 00:11:13.990
and meteor impact site is quite


00:11:14.000 --> 00:11:15.829
fascinating What's the idea that the


00:11:15.839 --> 00:11:18.230
asteroids slammed into the earth and it


00:11:18.240 --> 00:11:20.150
melted everything underneath and that


00:11:20.160 --> 00:11:21.990
went all the way deep into the went into


00:11:22.000 --> 00:11:23.910
the deep mantle because some of these


00:11:23.920 --> 00:11:26.069
cratons can can go close to the core


00:11:26.079 --> 00:11:27.910
mantle boundary that melted material


00:11:27.920 --> 00:11:30.069
just upworld because of the the lack of


00:11:30.079 --> 00:11:31.829
pressure and so it was able to upworld


00:11:31.839 --> 00:11:33.509
towards the surface towards the crust


00:11:33.519 --> 00:11:35.750
Absolutely That's the that's the key


00:11:35.760 --> 00:11:38.310
point this decompression The earth is a


00:11:38.320 --> 00:11:40.069
layered structure and we have this rigid


00:11:40.079 --> 00:11:42.630
lithosphere crust which is sitting on


00:11:42.640 --> 00:11:45.110
top of the convecting mantle underneath


00:11:45.120 --> 00:11:47.829
and the convecting mantle is primed to


00:11:47.839 --> 00:11:50.550
melt and think of it like slowmoving


00:11:50.560 --> 00:11:52.710
molasses or honey Yes You can also think


00:11:52.720 --> 00:11:54.710
of it as a bit like a champagne bottle


00:11:54.720 --> 00:11:56.630
if you like So the only thing that's


00:11:56.640 --> 00:11:59.350
stopping the molasses the convecting


00:11:59.360 --> 00:12:01.269
mantle from melting is the fact that


00:12:01.279 --> 00:12:03.750
it's got a a lid on it This lithosphere


00:12:03.760 --> 00:12:05.350
Okay So that's like the cork in the


00:12:05.360 --> 00:12:07.350
champagne bottle As soon as you remove


00:12:07.360 --> 00:12:09.829
that lithosphere or you remove the cork


00:12:09.839 --> 00:12:12.150
everything goes mad and your champagne


00:12:12.160 --> 00:12:13.910
starts squirting out the top It's


00:12:13.920 --> 00:12:15.829
exactly the same for the mantle If you


00:12:15.839 --> 00:12:17.750
remove the lithosphere in with a big


00:12:17.760 --> 00:12:19.750
impact then the underlying mantle will


00:12:19.760 --> 00:12:22.629
melt profusely and produce huge volumes


00:12:22.639 --> 00:12:25.110
of bassalt So you'll get something like


00:12:25.120 --> 00:12:27.750
an oceanic plateau So something like on


00:12:27.760 --> 00:12:29.829
Java or even Hawaii those sorts of


00:12:29.839 --> 00:12:32.870
things But because Earth had still


00:12:32.880 --> 00:12:34.710
retained its water it still had a


00:12:34.720 --> 00:12:36.949
hydrosphere and and that hydrosphere is


00:12:36.959 --> 00:12:39.190
still around You then offer yourself the


00:12:39.200 --> 00:12:42.509
possibility of reprocessing that thick


00:12:42.519 --> 00:12:45.910
basultic pile of rocks into more evolved


00:12:45.920 --> 00:12:48.310
continental rocks granics if you like So


00:12:48.320 --> 00:12:50.389
the pale colored rocks And once you've


00:12:50.399 --> 00:12:52.710
formed those pale colored rocks they're


00:12:52.720 --> 00:12:54.790
really stable because they're they're


00:12:54.800 --> 00:12:56.870
much less dense than the basil And they


00:12:56.880 --> 00:12:59.509
basically float and and stay around for


00:12:59.519 --> 00:13:01.350
billions of years as as we know they


00:13:01.360 --> 00:13:03.750
have And one of the fundamental things


00:13:03.760 --> 00:13:05.750
about platons one of the fundamental


00:13:05.760 --> 00:13:07.910
observations that anybody can make when


00:13:07.920 --> 00:13:09.750
looking on Google Earth or geological


00:13:09.760 --> 00:13:12.230
maps is that they are uncommonly round


00:13:12.240 --> 00:13:14.550
And you need to provide a decent


00:13:14.560 --> 00:13:16.710
explanation as to why that would be


00:13:16.720 --> 00:13:18.310
because it's important I think


00:13:18.320 --> 00:13:20.470
geologists have perhaps forgotten what


00:13:20.480 --> 00:13:22.790
we have traditionally been good at which


00:13:22.800 --> 00:13:24.870
is making straightforward observations


00:13:24.880 --> 00:13:27.990
mapping things and recognizing patterns


00:13:28.000 --> 00:13:29.829
and then trying to interpret those


00:13:29.839 --> 00:13:31.509
patterns That's exactly how we


00:13:31.519 --> 00:13:33.590
discovered plate tectonics the patterns


00:13:33.600 --> 00:13:36.069
of the magnetic reversals on the seabed


00:13:36.079 --> 00:13:38.470
allowed people to interpret those that


00:13:38.480 --> 00:13:41.190
they were sites of creation of new crust


00:13:41.200 --> 00:13:43.030
That's how geology came about in the


00:13:43.040 --> 00:13:45.509
first place an observation was made of


00:13:45.519 --> 00:13:48.710
rocks on a cliff and they noticed that


00:13:48.720 --> 00:13:51.750
Yeah it was folded over Exactly Exactly


00:13:51.760 --> 00:13:53.350
And it would have taken time for that


00:13:53.360 --> 00:13:55.430
folding to take place Of course Of


00:13:55.440 --> 00:13:57.430
course And and it's those fundamental


00:13:57.440 --> 00:13:59.350
observations that people interpret And


00:13:59.360 --> 00:14:01.750
of course you know way back in the 17th


00:14:01.760 --> 00:14:03.590
and 18th century we didn't have any


00:14:03.600 --> 00:14:05.829
machinery to measure isotopes or trace


00:14:05.839 --> 00:14:07.269
elements or anything like that It really


00:14:07.279 --> 00:14:09.110
was what you can see with your eyes and


00:14:09.120 --> 00:14:10.949
map out to try and make sense of that


00:14:10.959 --> 00:14:12.949
But just fundamental observations such


00:14:12.959 --> 00:14:15.350
as catton if you look at maps of the


00:14:15.360 --> 00:14:17.509
Pilra caton or even the old one of the


00:14:17.519 --> 00:14:20.069
oldestratons the slaveraton it's just


00:14:20.079 --> 00:14:22.790
uncommonly round a circular feature and


00:14:22.800 --> 00:14:24.710
then that's a very hard thing to do with


00:14:24.720 --> 00:14:27.189
plate tectonics plate tectonics features


00:14:27.199 --> 00:14:29.670
like spreading ridges or continental


00:14:29.680 --> 00:14:31.910
arcs like Japan and Indonesia they're


00:14:31.920 --> 00:14:33.750
all these big long linear features


00:14:33.760 --> 00:14:35.829
that's exactly what you would expect if


00:14:35.839 --> 00:14:37.990
you have rigid plates jostling against


00:14:38.000 --> 00:14:39.670
each other and where they meet that's


00:14:39.680 --> 00:14:41.189
where all the action is happening But


00:14:41.199 --> 00:14:42.870
you wouldn't expect plate tectonics to


00:14:42.880 --> 00:14:44.710
produce anything like a a circular


00:14:44.720 --> 00:14:46.310
structure You would expect that to


00:14:46.320 --> 00:14:49.189
result from either impacts or these


00:14:49.199 --> 00:14:51.509
mantle plumes that is the other sort of


00:14:51.519 --> 00:14:53.670
widely held This is the hot spots like


00:14:53.680 --> 00:14:56.230
Hawaii and Iceland Precisely Yes So in


00:14:56.240 --> 00:14:57.829
the earlier well the earth certainly


00:14:57.839 --> 00:14:59.350
would have been hotter and you might


00:14:59.360 --> 00:15:01.269
expect mental plumes to have been even


00:15:01.279 --> 00:15:03.509
more vigorously active but it just


00:15:03.519 --> 00:15:06.550
doesn't make sense when you compare the


00:15:06.560 --> 00:15:08.389
likelihood that the impacts could have


00:15:08.399 --> 00:15:09.990
given rise to the same thing That's


00:15:10.000 --> 00:15:12.269
Professor Tim Johnson from Curtain


00:15:12.279 --> 00:15:15.829
University and this is spacetime Still


00:15:15.839 --> 00:15:18.470
to come a new study suggests water ice


00:15:18.480 --> 00:15:20.230
may be present just a few centimeters


00:15:20.240 --> 00:15:22.790
below the lunar surface over a far wider


00:15:22.800 --> 00:15:24.790
area of the moon's polar regions than


00:15:24.800 --> 00:15:27.110
previously thought And the United States


00:15:27.120 --> 00:15:29.990
secret X37B space shuttle returns to


00:15:30.000 --> 00:15:31.910
Earth following its latest classified


00:15:31.920 --> 00:15:34.389
mission All that and more still to come


00:15:34.399 --> 00:15:50.590
on


00:15:50.600 --> 00:15:53.509
Spaceime A new study suggests that water


00:15:53.519 --> 00:15:55.350
ice may be present just a few


00:15:55.360 --> 00:15:57.509
centimeters below the lunar surface over


00:15:57.519 --> 00:15:59.509
a far greater area of the moon's polar


00:15:59.519 --> 00:16:02.069
regions than previously thought The


00:16:02.079 --> 00:16:03.590
findings reported in the journal


00:16:03.600 --> 00:16:05.430
communications earth and environment are


00:16:05.440 --> 00:16:07.430
based on observations by the Indian


00:16:07.440 --> 00:16:09.550
Chandrean 3 mission in


00:16:09.560 --> 00:16:12.230
2023 It showed that the moon's surface


00:16:12.240 --> 00:16:14.629
is covered by large yet highly localized


00:16:14.639 --> 00:16:17.430
variations in surface temperatures It's


00:16:17.440 --> 00:16:19.430
an important factor because future


00:16:19.440 --> 00:16:21.430
long-term exploration and habitation of


00:16:21.440 --> 00:16:23.269
the moon will depend on the availability


00:16:23.279 --> 00:16:25.910
of ice to provide water So far


00:16:25.920 --> 00:16:27.509
measurements have shown the presence of


00:16:27.519 --> 00:16:29.749
water ice in cold sinks These are the


00:16:29.759 --> 00:16:31.749
dark permanently shadowed floors of deep


00:16:31.759 --> 00:16:33.910
polar craters that never experience any


00:16:33.920 --> 00:16:35.990
sunlight The only previous direct


00:16:36.000 --> 00:16:37.269
measurements of lunar surface


00:16:37.279 --> 00:16:39.110
temperatures were taken way back in the


00:16:39.120 --> 00:16:42.069
1970s by the Apollo missions However


00:16:42.079 --> 00:16:43.590
those missions all landed near the


00:16:43.600 --> 00:16:45.590
equator where terrain slopes had little


00:16:45.600 --> 00:16:47.990
effect on temperature The sites were


00:16:48.000 --> 00:16:49.670
several thousand kilometers from the


00:16:49.680 --> 00:16:51.670
proposed southern polar landing sites


00:16:51.680 --> 00:16:53.430
now being selected for the future


00:16:53.440 --> 00:16:56.069
Artemis man missions The study's lead


00:16:56.079 --> 00:16:57.990
author Dugra Prasad from India's


00:16:58.000 --> 00:16:59.910
physical research laboratory analyzed


00:16:59.920 --> 00:17:01.749
temperature readings taken on the lunar


00:17:01.759 --> 00:17:04.470
surface and down to a depth of 10 cm by


00:17:04.480 --> 00:17:05.990
a temperature probe experiment aboard


00:17:06.000 --> 00:17:08.309
the Changeran 3 vicram lander which


00:17:08.319 --> 00:17:09.829
touched down right at the edge of the


00:17:09.839 --> 00:17:12.390
lunar south pole Brasard and colleagues


00:17:12.400 --> 00:17:13.829
found that temperatures at the landing


00:17:13.839 --> 00:17:16.150
site a sun-facing slope angle at about


00:17:16.160 --> 00:17:20.150
6° peaked at around 355 Kelvin that's 82


00:17:20.160 --> 00:17:23.590
degrees C and dropped to 105 Kelvin


00:17:23.600 --> 00:17:27.990
that's - 168° C during the lunar night


00:17:28.000 --> 00:17:30.789
However a lower peak temperature of 332


00:17:30.799 --> 00:17:34.070
Kelvin or 59° C was measured on a flat


00:17:34.080 --> 00:17:36.789
region just a meter away The authors


00:17:36.799 --> 00:17:39.029
then use this collected data to derive a


00:17:39.039 --> 00:17:41.350
model of how slope angle affects surface


00:17:41.360 --> 00:17:43.190
temperatures on the moon especially at


00:17:43.200 --> 00:17:44.950
higher lunar latitudes similar to the


00:17:44.960 --> 00:17:47.430
landing site The model indicated that


00:17:47.440 --> 00:17:49.510
for slopes facing away from the sun and


00:17:49.520 --> 00:17:51.590
towards the nearest pole a slope with an


00:17:51.600 --> 00:17:54.549
angle greater than 14° may well be cool


00:17:54.559 --> 00:17:56.630
enough for ice to accumulate close to


00:17:56.640 --> 00:17:58.870
the surface And this is similar to


00:17:58.880 --> 00:18:01.029
conditions at the lunar poles including


00:18:01.039 --> 00:18:02.870
those at the proposed landing sites for


00:18:02.880 --> 00:18:05.110
Artemus The authors therefore suggest


00:18:05.120 --> 00:18:06.789
that areas on the moon where the ice can


00:18:06.799 --> 00:18:09.270
form may be far more numerous and easier


00:18:09.280 --> 00:18:12.470
to access than previously thought This


00:18:12.480 --> 00:18:15.590
is spaceime Still to come America's


00:18:15.600 --> 00:18:18.390
super secret X37b space shuttle returns


00:18:18.400 --> 00:18:19.990
to Earth following its latest mission


00:18:20.000 --> 00:18:22.310
And later in the science report we may


00:18:22.320 --> 00:18:24.950
finally be a step closer to a once a


00:18:24.960 --> 00:18:27.110
year injection which could help prevent


00:18:27.120 --> 00:18:29.990
HIV infection All that and more coming


00:18:30.000 --> 00:18:46.430
up on


00:18:46.440 --> 00:18:49.029
Spaceime The United States Space Force's


00:18:49.039 --> 00:18:51.830
highly secretive X37B space shuttle has


00:18:51.840 --> 00:18:54.270
returned to Earth following a classified


00:18:54.280 --> 00:18:57.110
434-day orbital mission It was the


00:18:57.120 --> 00:18:58.870
seventh mission for the program which


00:18:58.880 --> 00:19:00.870
uses two of the wing space planes to


00:19:00.880 --> 00:19:03.029
undertake specialist orbital testing and


00:19:03.039 --> 00:19:05.669
reconnaissance operations The landing at


00:19:05.679 --> 00:19:07.430
the Vandenberg Space Force Base in


00:19:07.440 --> 00:19:09.590
California took place appropriately


00:19:09.600 --> 00:19:11.350
under the cover of darkness in the


00:19:11.360 --> 00:19:13.190
middle of the night and the touchdown


00:19:13.200 --> 00:19:15.350
wasn't publicly announced until several


00:19:15.360 --> 00:19:18.150
hours after its pre-dawn return The


00:19:18.160 --> 00:19:19.750
mission had launched aboard SpaceX


00:19:19.760 --> 00:19:21.990
Falcon Heavy rocket from NASA's Kennedy


00:19:22.000 --> 00:19:25.590
Space Center way back in December 2023


00:19:25.600 --> 00:19:27.830
While few details were released by Space


00:19:27.840 --> 00:19:29.909
Force mission managers they did say the


00:19:29.919 --> 00:19:31.590
flight successfully demonstrated the


00:19:31.600 --> 00:19:33.750
vehicle's ability to change orbits by


00:19:33.760 --> 00:19:35.830
using aerobreing that is atmospheric


00:19:35.840 --> 00:19:38.870
drag to slow down in the process saving


00:19:38.880 --> 00:19:41.590
valuable fuel And that's an important


00:19:41.600 --> 00:19:42.870
development because one of the big


00:19:42.880 --> 00:19:45.909
advantages of the X37B is its ability to


00:19:45.919 --> 00:19:48.470
easily change orbits making it difficult


00:19:48.480 --> 00:19:50.950
for the enemy to keep track of Following


00:19:50.960 --> 00:19:52.710
its deployment from the Falcon into a


00:19:52.720 --> 00:19:54.549
highly elliptical orbit the reusable


00:19:54.559 --> 00:19:56.390
space plane conducted what Space Force


00:19:56.400 --> 00:19:58.630
describes as space domain awareness


00:19:58.640 --> 00:20:00.630
technology experiments that aim to


00:20:00.640 --> 00:20:02.830
improve America's knowledge of the space


00:20:02.840 --> 00:20:05.190
environment Now that word salad suggests


00:20:05.200 --> 00:20:06.950
that one of its functions is close


00:20:06.960 --> 00:20:09.430
proximity inspector missions studying


00:20:09.440 --> 00:20:11.669
imaging and maybe even attaching spy


00:20:11.679 --> 00:20:14.549
equipment onto enemy satellites First


00:20:14.559 --> 00:20:16.710
launched back in 2010 the Boeing made


00:20:16.720 --> 00:20:18.710
autonomous spacecraft are based on a


00:20:18.720 --> 00:20:20.470
prototype originally developed to be


00:20:20.480 --> 00:20:22.230
transported into space in the payload


00:20:22.240 --> 00:20:24.150
bay of NASA's space shuttle fleet and


00:20:24.160 --> 00:20:25.990
then deployed on missions lasting well


00:20:26.000 --> 00:20:29.830
over 900 days And the previous X37B


00:20:29.840 --> 00:20:33.669
mission OTV6 lasted 98 days in orbit


00:20:33.679 --> 00:20:36.470
Genuine proof of concept This is


00:20:36.480 --> 00:20:52.789
spaceime


00:20:52.799 --> 00:20:54.549
And time now to take a brief look at


00:20:54.559 --> 00:20:56.149
some of the other stories making news in


00:20:56.159 --> 00:20:59.029
science this week with a science report


00:20:59.039 --> 00:21:01.350
Early stage trials suggesting that a


00:21:01.360 --> 00:21:04.070
once a year injection to prevent HIV may


00:21:04.080 --> 00:21:07.110
now be a step closer to fruition


00:21:07.120 --> 00:21:09.830
HIV is the human immuno deficiency virus


00:21:09.840 --> 00:21:13.110
which causes AIDS The findings reported


00:21:13.120 --> 00:21:15.110
in the Lancet medical journal found that


00:21:15.120 --> 00:21:17.430
one injection of the drug licamp into


00:21:17.440 --> 00:21:19.270
the muscle resulted in the compound


00:21:19.280 --> 00:21:20.950
remaining detectable in the blood for at


00:21:20.960 --> 00:21:24.310
least 56 weeks At the one-year mark the


00:21:24.320 --> 00:21:26.149
study found the drug was safe and that


00:21:26.159 --> 00:21:27.510
blood levels of the drug were still


00:21:27.520 --> 00:21:29.270
higher than those recorded in previous


00:21:29.280 --> 00:21:30.870
studies where the drug was shown to


00:21:30.880 --> 00:21:33.830
block HIV transmission However as a


00:21:33.840 --> 00:21:35.430
phase one study the trial didn't


00:21:35.440 --> 00:21:36.630
actually measure the drug's


00:21:36.640 --> 00:21:38.310
effectiveness at preventing HIV


00:21:38.320 --> 00:21:40.310
infection and so further clinical trials


00:21:40.320 --> 00:21:41.830
will be needed including with


00:21:41.840 --> 00:21:43.430
participants from more diverse


00:21:43.440 --> 00:21:45.149
population


00:21:45.159 --> 00:21:47.669
sets Scientists say the record-breaking


00:21:47.679 --> 00:21:50.149
high sea temperatures of 2023 and 24


00:21:50.159 --> 00:21:52.390
were strange but not totally unexpected


00:21:52.400 --> 00:21:54.789
when looking at climate models A report


00:21:54.799 --> 00:21:56.310
in the journal Nature's found that


00:21:56.320 --> 00:21:58.230
global sea surface temperatures reached


00:21:58.240 --> 00:22:00.149
record highs breaking the previous


00:22:00.159 --> 00:22:04.310
records by around 0.25° 25° C The sudden


00:22:04.320 --> 00:22:06.149
increase raised concerns that global


00:22:06.159 --> 00:22:08.230
warming might be accelerating faster


00:22:08.240 --> 00:22:10.230
than models had predicted However


00:22:10.240 --> 00:22:11.990
looking at observation-based statistical


00:22:12.000 --> 00:22:13.750
models the authors found the jump was


00:22:13.760 --> 00:22:16.549
considered to be a 1 in 512-year event


00:22:16.559 --> 00:22:19.190
relative to current warming trends This


00:22:19.200 --> 00:22:20.789
means that while such an anomaly would


00:22:20.799 --> 00:22:22.710
have been practically impossible without


00:22:22.720 --> 00:22:24.870
current global warming trends the events


00:22:24.880 --> 00:22:27.909
not entirely unexpected


00:22:27.919 --> 00:22:29.909
Paleontologists have discovered red


00:22:29.919 --> 00:22:31.990
dinosaur footprints hiding in plain


00:22:32.000 --> 00:22:34.149
sight at a central Queensland high


00:22:34.159 --> 00:22:36.230
school A report in the journal


00:22:36.240 --> 00:22:38.789
Historical Biology identified 66


00:22:38.799 --> 00:22:40.950
fossilized footprints on a boulder at


00:22:40.960 --> 00:22:42.310
the school representing one of the


00:22:42.320 --> 00:22:44.149
highest concentrations of dinosaur


00:22:44.159 --> 00:22:45.909
footprints per square meter ever


00:22:45.919 --> 00:22:48.630
documented in Australia The footprints


00:22:48.640 --> 00:22:51.750
are from 47 individual dinosaurs which


00:22:51.760 --> 00:22:53.990
passed across a patch of wet clay while


00:22:54.000 --> 00:22:55.990
walking along or crossing a waterway


00:22:56.000 --> 00:22:57.990
during the early Jurassic some 200


00:22:58.000 --> 00:23:00.230
million years ago The three-toed


00:23:00.240 --> 00:23:02.149
footprints belong to the ignore species


00:23:02.159 --> 00:23:04.390
Aurpus Scampus a small bipedal


00:23:04.400 --> 00:23:06.870
herbiviverous dinosaur between 15 and 50


00:23:06.880 --> 00:23:09.350
cm in length with long legs a chunky


00:23:09.360 --> 00:23:11.750
body short arms and a small head and


00:23:11.760 --> 00:23:13.669
beak The boulder containing the


00:23:13.679 --> 00:23:15.590
footprints was uncovered some 20 years


00:23:15.600 --> 00:23:17.830
ago at a local mine and then given to


00:23:17.840 --> 00:23:20.270
the local high school And it wasn't


00:23:20.280 --> 00:23:22.789
alone A second rock also containing


00:23:22.799 --> 00:23:24.630
dinosaur footprints from two different


00:23:24.640 --> 00:23:26.630
species was found decorating the mine's


00:23:26.640 --> 00:23:28.710
car park entrance while a third much


00:23:28.720 --> 00:23:30.789
smaller dinosaur footprint covered rock


00:23:30.799 --> 00:23:32.870
had been encased in resin and was being


00:23:32.880 --> 00:23:50.070
used in the office as a bookend


00:23:50.080 --> 00:23:53.190
and that's the show for now Spaceime is


00:23:53.200 --> 00:23:55.029
available every Monday Wednesday and


00:23:55.039 --> 00:23:57.669
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