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This is Space Time Series 27 Episode 37 for broadcast on the
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25th of March 2024. Coming up on Space Time, a new spin on the
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red supergiant star Betelgeuse, how asteroid and comet
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bombardment change the Moon forever, and New Zealand's
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Electron Rocket undertakes its first NRO launch from American
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soil. All that and more coming up on Space Time.
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Welcome to Space Tiles with Stuart Garry. Thank you A new
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study suggests that evidence of what appears to be a
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faster-than-expected rotation observed on the red supergiant
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star Betelgeuse could instead be its violently boiling surface.
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The high spin rate was detected a few years ago when astronomers
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began focusing on Betelgeuse after it began to dramatically
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change in brightness.
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The behemoth rapidly dimmed from being the ninth brightest star
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in the night sky down to below 20. The star's dimming
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brightness led to speculation that it was about to go
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supernova, which is the next logical step in its evolution.
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Betelgeuse is expected to explode as a core collapse or
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type 2 supernova pretty well any day now, which in astronomical
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terms could mean a million years from now, or it could mean
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tomorrow. When it does explode, Betelgeuse will temporarily
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outshine all the other stars in our galaxy, and it will be
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clearly visible in the daytime sky here on Earth.
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The last star seen by humans to go supernova in our galaxy was
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Tycho's star back in 1572. That was before the invention of the
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telescope. However, the dimming of Betelgeuse was later put down
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to the expulsion of a massive cloud of dust which blocked our
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view of the star.
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Located somewhere between 530 and 643 light years away,
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Betelgeuse is the brightest star in the constellation Orion, and
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one of the largest and most luminous stars visible with the
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unaided eye. The red supergiant represents the scorpion Sting on
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Orion's shoulder. Now, although I've been calling it Betelgeuse,
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it's more commonly these days referred to simply as
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Betelgeuse.
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Don't say the name three times. But the name has gone through
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centuries of tortured mispronunciation. It originally
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started out as Ibt Al-Yawza, meaning the hand of the big man
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in Arabic, the big man being Orion The Hunter. Betelgeuse
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began its life only about 10 million years ago as a massive
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spectrotype OB blue star.
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By comparison, our much smaller Sun is some 4.6 billion years
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old and will probably keep shining for another 7 billion
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years. That's because the Sun's much smaller than Betelgeuse and
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so burns through its nuclear fuel supply much slower.
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Calculations of Betelgeuse's mass range from slightly under
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10 to a little over 20 times that of our Sun, with some
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100 times the Sun's brightness and around 1
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times its diameter. If Betelgeuse were put where the
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Sun is at the centre of our solar system, its surface would
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extend out to almost as far as Jupiter, therefore engulfing the
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orbits of Mercury, Venus, Earth, Mars and the main asteroid belt.
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But Betelgeuse's future is limited. It is now a bloated old
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semi-regular variable red supergiant. Red supergiants are
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the largest stars in the universe in terms of their
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volume, although they're not the most massive or luminous stars
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around. Now, stars this big aren't supposed to rotate very
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fast.
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In their evolution, most stars expand and spin down to conserve
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angular momentum. However, recent observations suggest that
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Betelgeuse is rotating incredibly fast at some 5
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kilometers per second. And that 's two orders of magnitude
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faster than what a single evolved star should be spinning
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at.
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The most prominent evidence of Betelgeuse's rotation has come
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from ALMA, the Atacama Large Millimeter Submillimeter Array
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Radio Telescope in Chile. ALMA's 66 antennas work together as a
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giant single dish, a technique known as radio interferometry.
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Using this technique, astronomers discovered a dipolar
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radial velocity map on the outer layer of Betelgeuse.
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Now, put simply, the data shows that one half of the star
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appears to be moving towards us, while the other half, the
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opposite half, appears to be rotating away. That tells
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scientists the star is spinning. And the rate at which that
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occurs tells us exactly how fast the star is spinning and
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Betelgeuse is spinning quickly.
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Now this interpretation should have been a clear open and shut
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case. What if Betelgeuse was a perfectly round sphere? However,
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the surface of Betelgeuse is actually boiling quite
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violently. The heaving and convecting bubbles can be as
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large as the Earth's orbit around the Sun, which means it's
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covering a significant fraction of Betelgeuse's surface.
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And these convecting bubbles are rising and falling at speeds of
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up to 30 km per second. Now, based on this picture, an
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international team led by Xingzi Ma from the Max Planck Institute
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Of Astrophysics in Germany has offered an alternative
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explanation to Betelgeuse's velocity map.
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What we're in fact seeing is Betelgeuse's boiling surface
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mimicking rotation. Reporting in the Astrophysical Journal
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Letters, Xingzi Ma proposes that a cluster of boiling bubbles
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rise on one side of the star while at the same time another
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group of bubbles is sinking on the other.
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Due to the limited resolution of the ALMA telescope, these
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convective motions would be blurred in actual observations,
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and that could result in the dipolar velocity map. The
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authors developed a new post-processing package to
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produce synthetic ALMA images in submillimeter spectra from their
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three-dimensional rotational hydrodynamic simulations of
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non-rotating red supergiant stars.
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They found that in 90% of simulations, the star would be
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interpreted as rotating at several kilometers per second
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simply because of the large-scale boiling motions on
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its surface. And those motions couldn't be clearly identified
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in the ALMA telescope.
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Of course, further observations are now needed to better assess
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the rapid rotation or surface boiling of Betelgeuse, and the
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authors are hoping to make predictions for future
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observations with high spatial resolution. Fortunately, other
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astronomers have already made higher resolution observations
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of Betelgeuse in 2022, and that new data which is now being
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examined will test this new hypothesis.
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We'll keep you informed. This is Space Time. Still to come, how
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asteroid and comet bombardments have changed the face of the
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Moon forever, and New Zealand's Electron Rocket has undertaken
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its first NRO launch from United States soil. All that and more
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coming up. On Space Time.
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A new study has found that the Earth's Moon may have been
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subjected to far more asteroid, comet and meteor impact events
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than previously thought. The findings, reported in the
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journal Nature Communications, provides a new picture of the
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Moon's earliest geological evolution.
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The study's lead author, Katerina Milchkiewicz from
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Curtin University, says the new research is providing greater
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insight into how the oldest impact events on the Moon may
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have left near-invisible cratering imprints, offering a
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unique perspective about the evolution of the Earth-Moon
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system.
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She says the lunar craters may have looked significantly
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different if they occurred while the Moon was still cooling
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following its initial formation.
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If these large impact craters, often referred to as impact
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basins, formed during the Lunar Magma ocean solidification
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period, that's more than 4 billion years ago, they should
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have produced different looking craters compared to those that
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formed later in the Moon's geologic history. A very young
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Moon had formed with a global magma ocean that cooled over
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millions of years to form the Moon we see today.
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So, when asteroids and other bodies hit the softer lunar
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surface, it really shouldn't have left such severe imprints.
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In other words, there would have been little geological or
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geophysical evidence that the impacts had occurred.
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Medjkovic says the timeframe for the solidification of the Lunar
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Magma ocean varies significantly between different studies, but
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it could have been prolonged enough to experience some of the
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large impact bombardment history typical of the earliest periods
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of the solar system's evolution.
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As the Moon ages and its surface cools, it becomes harder, and
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the bombardment imprints are a lot more noticeable by remote
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sensing. Milchkovic says it's imperative to understand the
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bombardment and cratering record of the earliest epoch of the
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solar system's history in order to complete the story of how the
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Sun's planets formed and evolved.
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Right now, the Moon's thought to have formed through a collision
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between the early proto-Earth and a Mars-Sized planet called
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Theia, which slammed into the Earth. That caused both bodies
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to melt, forming a magma ocean, eventually solidifying to form
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the Earth.
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But some of the ejecta from that collision was flung into orbit
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around the molten body. That eventually coalesced and formed
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the Moon. That was four and a half billion years ago. But it
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wasn't the end of impact events.
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As Jupiter moved in towards the inner solar system and then back
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out again to its current orbital position, it flung a lot of
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small objects all over the solar system, creating what
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astronomers call the late heavy bombardment. That was about 3.9
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billion years ago. And we think that's where the Moon got most
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of its craters.
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But of course, it's all hypothesis. By comparing
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different perspectives of asteroid dynamics and lunar
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evolution modelling, research suggests that the Moon may have
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been missing evidence of its earliest cratering record.
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Milchkiewicz says her research aims to explain the discrepancy
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between theory and observations of the lunar cratering record.
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Translating this finding will help future research understand
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the impact that the early Earth could have experienced and how
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that would have affected our planet's evolution.
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I've been looking at big craters on the Moon for for a number of
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years. And then what actually allowed us and enabled us to
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actually start looking into these big craters in more detail
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was the NASA GRAIL mission that orbited the Moon. Several years
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ago, we had a really beautiful mission that mapped the gravity
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of the Moon in a very high resolution.
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And that new map gave us insights into the subsurface
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structure. And the crustal structure of the Moon and
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because impact and big craters really make an imprint in the
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crust and we can start looking at those big craters with a
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different set of eyes, if you will. So that's kind of the
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origins of... Are starting to look at those big impacts on the
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Moon and lunar bombardment in the first place.
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You had some really great results from GRAIL, which gave
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you some fascinating insights.
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So the GRAIL gave us a new resolution, like an updated, a
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better resolution observation of the subsurface. What we get is
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with the gravity signature, as the spacecraft were flying
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around and orbiting the Moon, they were actually mapping the
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gravity field, and with that, the distribution of mass and
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different densities in the subsurface.
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Because obviously gravity varies. It varies because mass
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distribution is different and the density is different in the
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subsurface. So we could look at, when we subtract the topography,
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we could actually look at these different mass concentrations in
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the subsurface of the Moon.
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So we started looking more at what's happening in the crust,
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what's happening in the upper mantle, and with that, an
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impact. That was my particular interest, was to look at how
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these big impacts. So one of the things that we noticed very
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early on is that if we look at all the Mare region, those are
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those big impacts.
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And if you look up on the Moon and you see all the dark areas,
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the Mare region, they're actually floors of these big
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craters. So when we looked at the eyes of gravity and reverted
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that in crustal thickness map, we saw that the crust is quite
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thin at the bottom of these craters across this Mare region.
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So I started doing some numerical modeling of how these
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big impacts would form, and it turned out that... Because the
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crust is quite thin on the Moon, like 34 to 43 kilometers in
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thickness on average, what we turn out is for those big
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craters that are a thousand kilometers across, when impact
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happens, they actually not only excavate the crust, they
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excavate the mantle as well, and they pull mantle closer to the
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surface.
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So as a product of crater formation, we actually end up
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with the crust in the bottom of these craters to be quite thin.
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So that was one of the big things that we could survey and
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explain the structure of the crust and the crustal thickness
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distribution normally and connect it to the crater
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formation.
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And as they predict that thinning come from impact
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craters, we can then look at different types of crustal
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thickness. Thermal evolution models and understand how Moon
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actually evolved as a Moon. So that was all back a while ago,
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just after GRAIL have given us the first data.
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But one of the outstanding things that was bothering me for
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quite a long time was actually to understand the very early
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evolution of the Moon. And that 's the new study that just came
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out. What got me interested is thinking about this massive
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bombardment and because we know that there have been...
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Now, when you say massive bombardment, you're talking
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about the light heavy bombardment about 3.9 billion
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years ago?
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Yes. So, yes, I'm thinking about light heavy bombardment. But the
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thing is, the term light heavy bombardment is becoming obsolete
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a little bit because the light heavy bombardment is a term that
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describes the earliest formation of the solar system after the
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planet has most formed and the planets have just.
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Formed as young planets and there has still been some
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leftover bombardment coming from asteroid belt or just the
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disturbances around the inner solar system and because we have
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the record on the Moon that kind of seizes at 3.9 or 3.7 even
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billion years ago we don't really not reach We have a tale
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of this late habitable environment, but we don't have
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the beginning.
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We don't know how the beginning of the late habitable
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environment looks like, which is why the term of late habitable
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environment, because we don't have the early habitable
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environment. We don't know how that part of the impactable
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environment looks like.
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All that's important because that lets us know when Jupiter
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did its grand tack.
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Exactly, yes. It's important because it tells us about this.
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And the final stage of planet formation, so it really gives
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the initial conditions to all the planets that we see in the
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inner solstice, including why are all in the planets different
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and why are all different sizes and why they all seem to have a
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different habitable or inhabitable conditions and so
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forth.
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So definitely we do want to know what are the initial conditions,
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if you will, for the formation of the solar system. So that's
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why we really all try to understand the earliest
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environment as best we can.
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When we look at the Moon, we can determine something a little bit
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about this late-heaven environment, or some people call
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it terminal catharsis, but we don't know what happened before
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then, whether we had even a higher flux or whether we had a
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lower flux, but then there was the disturbance that...
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About what he was saying about Jupiter passing. And that caused
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the excess bombardment around that period. So we don't really
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know that. And I think a lot of the new studies have been coming
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out trying to explain kind of the front end, if you will, of
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that heavy bombardment period.
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So my study is trying to give some insights into that because
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when we look through the GRAIL data, we see that there is
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different... I mean, it's not only through GRAIL data to be
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perfectly fair.
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There's been other studies in the past looking at... Lunar
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basins and these big craters, some of them look like more
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relaxed in geologic morphology or geophysical signature than
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others. So I started thinking about the notion of like, well,
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what if we had bombardment before the late Harry
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bombardment that was also heavy, but it happened on the Moon
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while Moon was still cooling.
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So we know that the ongoing or the state. Yeah, it's a gummy
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squid. Call it a squishy Moon, if you will. Some wanted me to
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call it cheese, but cheese is not as squishy when you hit it.
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It's kind of a squishy stick. The thing is, we know that the
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leading theory for the lunar formation is that an impact of
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the size of Mars hit the early Earth and broke off a little bit
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of material from the Earth, and those two have actually collided
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into kind of a new disk, and that disk seeded our Moon.
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That's an ongoing theory for the Moon formation. So if you have
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this young Moon forming, because it's coming from this kind of
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pan out little dish around the Earth, it has to be hot. It has
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to form kind of like a little magma ball.
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So we don't really know how long it took for that magma to cool
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and solidify and form the Moon as we know it today. But we know
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that, well, what we think we know is that it had a magma
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ocean that was global and it started to cool. And it started
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to cool within 10 million years.
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Or 500 million years, which would be kind of like the
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longest ever. We don't know that. Some theories suggest very
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short period of solidification, which are mostly like
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petrographic, petrological, or petrochemical calculations.
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But if you add any kind of dynamic instability, like tidal
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effect, or more impact, or anything dynamic, that cooling
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period has to become longer because you're not just cooling
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the system, you're adding more complexity to it. The point is
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that there is, like let's say in the last...
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10 years, there have been studies showing that if there is
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any kind of instabilities going on in terms of Moon's orbit
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around the Earth and any tidal motion and different things,
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that cooling of the magma ocean can last maybe a couple of
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hundred million years.
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And all of a sudden it's kind of biting into this bombardment
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period where you say, hang on a minute, surely if that is that
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long, then surely there should have been some impact happening
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in that period as well. So kind of that's where the idea for
00:18:23
this modelling work came. Came to be.
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So I've done a series of simulations that would kind of
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mimic bombardment under the residues of magma ocean if you
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will. So if there was partly solidified mantle, there is a
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flotation crust on it and kind of sandwich layer of melt
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between the crust and the mantle, then we're kind of
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modeling late stages of solidification of the Moon.
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And all the impacts that the simulations, these big impacts
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that are run is... It's showing that because of that little
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sandwiched layer of melt, that the crust ends up being squishy,
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if you will. So it basically relaxes and comes back to the
00:19:02
original, almost the original structure, as is like before
00:19:06
impact.
00:19:07
So if we were to look through the eyes of gravity, looking for
00:19:10
those subsurface differences in mass, we might not be able to
00:19:14
see them because the crust and the mount will just relax back
00:19:17
to the original position. Almost original positions.
00:19:20
So when we look at them today, we just simply can't find them.
00:19:24
And I think the smoking gun in this whole story wasn't just the
00:19:27
fact that the crust in the mantle relaxed and you don't see
00:19:29
it in gravity, but that if you look at the Moon or all the new,
00:19:34
all the kind of ongoing stuff that we know from observations
00:19:37
is that there are these so-called multi-ring basins on
00:19:40
the Moon.
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So it kind of has a rim, but there are some rings around it,
00:19:43
like Orion, Tau, or other big basins that preserve the
00:19:47
topographic structure.
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What the modeling showed is that if the Moon has been, let's call
00:19:53
it squishy, that we can't have those spaced out rings forming.
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Instead, what we get is kind of a graben structure with multiple
00:20:03
rings kind of happening very close to each other. So if you
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look at Jupiter's moons, like Ganymede, for example, or even
00:20:11
Europa, but Europa has a lot of...
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Tectonics going on but those icy moons they actually have this
00:20:17
kind of palimpsest basis they have this kind of circular but
00:20:20
graben structure rather than ring structure and i actually
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was getting more of that kind of morphology happening on the Moon
00:20:28
while there was my then the regular ring structure that we
00:20:32
see on a cold Moon.
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So that kind of also was, I think, the smoking gun showing
00:20:37
that not only that you can't see it in subsurface structure, you
00:20:40
also can't see it on topographic structure.
00:20:42
Yeah, but on Ganymede, that Graven structure, that could be
00:20:46
because there's a subsurface ocean there.
00:20:48
Absolutely, yeah. So some kind of a different rheology
00:20:51
happening in subsurface. Exactly. Yeah, definitely. It's
00:20:55
all to do with the kind of the strength of the lithosphere and
00:20:58
the response of the... Kind of body and how rigid it is when an
00:21:03
impact happens.
00:21:04
Are you seeing lots of differences between the
00:21:07
structure of craters on the near side and the far side of the
00:21:10
Moon? We know they do look very different. This dichotomy of the
00:21:14
lunar surface is very famous, but it's always been put out at
00:21:17
differences in the thickness of the crust. Are you seeing that
00:21:21
in the craters themselves?
00:21:22
Yes, we do.
00:21:24
We had a study in 2013 that came out of direct rail analysis that
00:21:30
showed that when we really compare the size of nearsight
00:21:34
basins with the average size of big basins on the far side, that
00:21:38
we see that the nearsight basins are actually much, much larger.
00:21:42
So almost... Twice as big than on the south side.
00:21:44
So the argument was, if we assume that the lunar surface
00:21:48
were to be bombarded equally across all sides, so there is no
00:21:52
preferential direction between the east side and south side.
00:21:55
And the astrodynamics really doesn't support any preferential
00:21:58
directions, then we would assume to have kind of a randomized
00:22:02
distribution of impact on both hemispheres.
00:22:05
But we don't. We see, let's say, we see eight big craters on the
00:22:09
near side, and then only one of that size or the size category
00:22:13
on the far side. And that one is also kind of on the limb, close
00:22:16
to the near side. So the explanation to that kind of
00:22:19
funky statistic comes from interior.
00:22:22
So it comes from asymmetric thermal evolution of the Moon.
00:22:26
So at the time when these big basins were formed, so we're now
00:22:29
talking more about the Lehigh environment, if you will, of
00:22:32
thermal cataclysm, so the big impact that occurred. The Moon
00:22:37
had cooled enough so it can capture and preserve them in the
00:22:39
record, in a cratering record.
00:22:41
So what we're seeing is that if the near side had a hotter
00:22:45
subsurface, so kind of a higher temperature gradient, so it had
00:22:49
a hotter subsurface because of high concentration of
00:22:52
radioactive elements that we call this so-called creek
00:22:55
terrain on the near side, that would have caused...
00:22:57
The localized increase in temperature in subsurface
00:23:01
compared to the far side that started cooling down normally
00:23:04
and had a cooler thermal gradient in subsurface. So when
00:23:07
we do simulations on a hot target versus cold target, we
00:23:10
actually end up for the same impact condition, near-side
00:23:13
basis could be up to twice as large as the ones on the far
00:23:17
side.
00:23:17
Is that due to tidal locking?
00:23:19
You mean the temperature asymmetry or the impact?
00:23:22
Temperature asymmetry.
00:23:23
That still remains an unopened question. Is? I think the
00:23:27
simplest explanation would be that it has to do something with
00:23:31
the tidal locking, with the tidal forces that causes the
00:23:35
nearsight hemisphere to A, have a thinner crust, and B, also
00:23:40
somehow has those heat-sucing elements.
00:23:43
Different minerals.
00:23:44
Kind of like concentrated under the crust underneath. We don't
00:23:48
have an explanation yet, like a smoking gun theory that would
00:23:54
say why, what. Promoted the asymmetry.
00:23:58
Some people even suggested it could have been an impact, but
00:24:01
that theory never really held water. So I do believe that if I
00:24:05
were to believe in a simpler solution, you know, Occam's
00:24:07
razor, I would probably say it probably had something to do
00:24:10
with the gravity and the fact that the young Moon had formed
00:24:14
quite closer to the Earth compared to today, because Moon
00:24:17
had been moving away from the Earth and, you know, beyond.
00:24:20
The thing in the house.
00:24:22
Yeah, yeah, it goes away the rate of how our fingers, like
00:24:27
nails grow, fingernails grow. The earliest impact that
00:24:29
happened on the Moon at 4.5, 4.4, maybe 4.3 years ago.
00:24:34
Probably in the first, let's say, 100 million years. Yeah. We
00:24:38
don't even have that in the geologic record of the Moon. We
00:24:41
can't tag any absolute value, any like absolute age to any of
00:24:45
the bases to be that old.
00:24:47
And it's simply because I think when they form, they form really
00:24:50
already relaxed, so it's hard to find them, but it's also hard to
00:24:53
find them because they are the oldest, so there has been
00:24:56
overprinting of new impacts on top of it, and so I think that
00:25:01
if I were to look for them, I'd just say I'm not.
00:25:04
Whoever wants to try to look for them, good luck. I don't think
00:25:07
they'll find them. But the whole point of the study wasn't to go
00:25:09
look for them. It's to bridge the gap between different
00:25:13
discipline research, if you will. So if we look at
00:25:16
astrodynamics, they've came up with the light-heavy bombardment
00:25:19
and the NEES model to explain the observations.
00:25:23
But if I say, well, you don't need to bother explaining
00:25:25
observations because impacts have been happening throughout
00:25:28
the entire early history of the solar system or the Moon, if you
00:25:32
will. So you don't need to explain the blip in observation.
00:25:36
For the lakehead environment.
00:25:37
It had been, let's say, if we assume it, it's been a steadily
00:25:41
declining impact block since 4.5 billion years to present day.
00:25:45
There haven't been much of a disturbance at all and you don't
00:25:48
see it in observations. Well, here is an explanation of why
00:25:51
you don't see it in observations, because they're
00:25:53
invisible.
00:25:53
You know, it's very hard to come up with a scientific theory that
00:25:57
claims something's invisible, but I've provided a whole lot of
00:26:01
justification as to why we wouldn't see it in the record,
00:26:04
which gives them the input to all the numerical modelers
00:26:07
looking at astrodynamics, that they don't need to satisfy
00:26:10
observations as we see them, because they could have been the
00:26:13
early period. They won't leave an imprint.
00:26:15
The early stuff hasn't left an imprint, so that's why there
00:26:18
appears to be a late heavy bombardment period, but there
00:26:22
may have been just as much stuff earlier on, just that would not
00:26:24
have left an imprint.
00:26:25
Correct. And I'm not saying that the late heavy bombardment
00:26:29
didn't happen. It could have been of less of an intensity. It
00:26:33
could have been with a different abnormality. It could have been
00:26:37
an event that Jupiter brought in as a disturbance into the inner
00:26:40
solar system.
00:26:41
What I'm saying is that the solar system before that point
00:26:44
in time may not need to be quiet, if you will. It could
00:26:48
have still had events and bombardment and impact flux
00:26:52
going around the inner solar system.
00:26:55
I think probably the key thing would be to try and look for
00:26:58
those evidences in other planetary bodies as well in the
00:27:00
inner solar system. So if we can find it elsewhere, that could be
00:27:05
evidence of this earliest bombardment moment, then... It
00:27:08
could tell us something more about and confirm the theories
00:27:11
we have about the Moon as well.
00:27:13
That's Katerina Miljkovic from Curtin University. And this is
00:27:18
Space Time. Still to come, New Zealand's Electron Rocket
00:27:22
undertakes its first NRO launch from American soil.
00:27:26
And later in the Science Report, the World Meteorological
00:27:29
Organization confirms that climate change has smashed all
00:27:33
records for greenhouse gas levels, temperature and sea
00:27:36
level rise and that the Earth's atmosphere is changing. All that
00:27:38
and more coming up on Space Time.
00:27:57
Rocket Lab have finally undertaken their first Electron
00:28:00
mission for the United States National Reconnaissance Office
00:28:02
from their new launch complex at NASA's Wallops Island flight
00:28:06
facility on the Virginian Mid-Atlantic coast. The launch,
00:28:10
named Live And Let Fly, was the 46th mission for the Electron
00:28:14
Rocket.
00:28:15
The highly secretive NRL-123 mission carried three classified
00:28:19
payloads into orbit. All previous Electron launches for
00:28:23
the National Reconnaissance Office have taken place from one
00:28:26
of Rocket Lab's two launch complexes at its Mahia Peninsula
00:28:29
launch complex on New Zealand's North Island. This is Space
00:28:33
Time.
00:28:50
And time now to take a brief look at some of the other
00:28:52
stories making use in science this week with the Science
00:28:54
Report. A new study by the Ward Meteorological Organization
00:28:59
shows that climate change has smashed all previous records for
00:29:02
greenhouse gas levels, surface temperatures, ocean heat and
00:29:06
acidification, sea level rise, Antarctic sea ice coverage, and
00:29:10
glacial retreating.
00:29:12
Additionally, they found that increases in heat waves, floods,
00:29:16
droughts, fires, and cyclones have cost the global economy
00:29:20
billions of dollars. The World Meteorological Organization
00:29:23
study says that 2023 was on average 1.45 degrees centigrade
00:29:29
above pre-industrial baseline levels.
00:29:32
Glaciers suffered the largest loss of ice on record and the
00:29:35
Antarctic sea ice was 1 million square kilometres below the
00:29:39
previous record year. However, they do say there was one small
00:29:44
glimmer of hope in the data. Renewable energy generation has
00:29:47
increased by almost 50% over the previous year.
00:29:52
A new study has found that getting the recommended 7-9
00:29:55
hours sleep a night is currently well out of reach for almost a
00:29:59
third of people. The findings reported in the journal Sleep
00:30:03
Health found 31% of adults had an average sleep duration
00:30:07
outside the recommended range.
00:30:09
The research by Flinders University found that only 15%
00:30:12
of people slept the recommended 7-9 hours for 5 or more nights
00:30:16
per week. And among those who did achieve the average of 7-9
00:30:21
hours per night over the 9-month monitoring period, about 40% of
00:30:25
the nights still fell outside the ideal range.
00:30:30
Assessments of 86 United States government staff and family
00:30:34
members who developed mysterious symptoms after serving Overseas,
00:30:37
something which has become known as Havana Syndrome, have failed
00:30:40
to find any significant clinical differences between these people
00:30:44
and a group of unaffected people.
00:30:47
Sufferers have reported intrusive sounds and head
00:30:49
pressures, often alongside dizziness, pain and visual
00:30:52
problems, among other symptoms, after serving Overseas. A report
00:30:56
in the Journal Of The American Medical Association says two new
00:31:00
studies have failed to find any significant differences in brain
00:31:03
structure or in most tests of auditory, vestibular, cognitive,
00:31:08
visual function or blood biomarkers between the two
00:31:11
groups.
00:31:12
In fact, the only differences they could find were in
00:31:14
self-reported and objective measurements of imbalance and
00:31:18
symptoms of fatigue, post-traumatic stress and
00:31:21
depression.
00:31:23
A new study claims a growing number of women are turning
00:31:26
towards non-traditional spiritual beliefs. These include
00:31:29
witchcraft, the occult, crystal meditations, as well as tarot
00:31:33
card and psychic readings. Tim Mendham from Australian Skeptics
00:31:37
says the Ibis Industry Report claims numbers have been
00:31:40
increasing for years now, with the COVID-19 lockdowns providing
00:31:45
an added additional boost.
00:31:46
Yeah, for a start, when I first read that headline, I was
00:31:48
surprised. I didn't know they were turned to witchcraft. But
00:31:51
this story actually covers a whole range of different
00:31:54
alternative practices like para-reading and psychics and
00:31:57
crystal ball gazing and everything. It's not really
00:31:59
witchcraft as you think of it.
00:32:00
And they're trying to think, are women turning to such practices
00:32:04
of late and why it might be happening? Now, you have to be
00:32:07
very careful about these things. You've obviously got very great
00:32:10
danger of gender stereotyping and that sort of stuff. But as a
00:32:13
background, in America, the psychic industry is growing by
00:32:15
about 2% a year.
00:32:16
The number of psychic crystal tarot card businesses is growing
00:32:19
by 1.6. And it's worth about $2.5 billion. I think I reckon
00:32:23
it's a lot more than that, actually, these days. So it's a
00:32:26
decent-sized industry that's making a lot of money. That
00:32:28
doesn't necessarily explain why people might be turning to these
00:32:31
things.
00:32:32
And the question is, are they turning to them? Well, the
00:32:34
suggestion is that women are more inclined to believe.
00:32:36
Believe these things than men. One survey showed that women are
00:32:40
more likely to say they've got the presence of a ghost or a
00:32:42
spiritual entity. About 46% of women compare with men, about
00:32:45
30%.
00:32:46
A similar trend we've seen also in the belief of psychics with
00:32:49
40% of women versus 29% of men. So the question is, why are
00:32:52
women more inclined to believe in these sort of things than
00:32:55
men? Could it be that men are more grounded in physical,
00:32:58
tangible things and women are more spiritual?
00:33:01
Men sort of go for the UFOs and Bigfoots, don't they?
00:33:04
I might say do, yes. Yes, and these sort of things which are
00:33:07
the more spiritual things, you tend to get a higher proportion
00:33:09
of women and they're all equally unsupported scientifically, the
00:33:13
things that they believe in.
00:33:14
It's just a different set of tools, you might say. And the
00:33:17
tool is for the reason that's suggesting that it's always the
00:33:19
reason put out is that in uncertain times, people are
00:33:22
searching for certainty. People don't like the idea that fate is
00:33:25
tough, right?
00:33:26
Anything can happen to you accidents do happen coincidences
00:33:29
do happen and that there is no rhyme or reason to necessarily
00:33:32
what's happening to the world or it doesn't care it doesn't care
00:33:35
at all and people want to be cared about so they turn into
00:33:38
something which gives them a pole to hang on to during the
00:33:41
flood there is something that they can sort of think this is
00:33:43
real this is something that i can get some emotional support
00:33:47
from in a world that looks like it's just totally random that's
00:33:49
a theory which is put out there quite often whether women are
00:33:52
more aware or concerned or scared of a world which is
00:33:56
uncertain.
00:33:57
Perhaps that is the case, and therefore that might be helpful
00:33:59
why there's a stronger belief in some of these spiritual beliefs
00:34:01
as opposed to the monster beliefs and that sort of stuff.
00:34:04
The trouble is you get all sorts of suggestions as to why it
00:34:06
might be happening.
00:34:07
You get all sorts of people who are hopping on a bandwagon.
00:34:09
Obviously the psychic fraternity would be saying people are
00:34:12
seeing more in their lives and opening up to opportunities. The
00:34:16
psychologist might say it's filling a gap. In their lives.
00:34:19
So there's various suggestions. It has always been the case that
00:34:22
women have believed more in these sorts of things, these
00:34:24
spiritual things, than men have. People have often wondered why.
00:34:28
And I think we'll be going on for a while trying to sort of
00:34:30
figure this one out.
00:34:31
That's Tim Minden from Australian Skeptics.
00:34:47
Thank you. Thank you.
00:34:50
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