SpaceTime Series 27 Episode 37
*Betelgeuse's Surprising Spin: A Red Supergiant's Secrets
Astronomers have been intrigued by the rapid rotation of the red supergiant star Betelgeuse, but new insights suggest its seemingly swift spin could be an illusion caused by its boiling surface. The star's dimming, once thought to herald an imminent supernova, turned out to be dust obscuring our view. Located in Orion, Betelgeuse's tumultuous surface, with convective bubbles the size of Earth's orbit, challenges our understanding of stellar dynamics.
*The Moon's Cratered Past: A History Written in Impacts
New research indicates the Moon endured more asteroid and comet bombardments than previously thought, potentially reshaping our knowledge of its geological history. This study reveals that early impacts may have left subtle marks, eluding detection due to a still-cooling lunar surface. As the Moon's magma ocean solidified, these ancient impacts could tell a tale of a dynamic early solar system.
*Rocket Lab's Historic NRO Mission from American Soil
Rocket Lab's Electron rocket has launched its first mission for the National Reconnaissance Office from NASA's Wallops Flight Facility in Virginia. The classified NRO-123 mission marks a new chapter for the company, expanding its launch capabilities beyond New Zealand's shores and continuing its streak of delivering payloads to orbit with precision.
*Climate Change Breaks New Records
The World Meteorological Organization reports unprecedented levels of greenhouse gases, warming temperatures, and rising seas, signaling an escalating climate crisis. Despite this, renewable energy sees a significant uptick, offering a beacon of hope amidst the environmental challenges.
*The Rise of Alternative Spirituality Among Women
An increasing number of women are exploring non-traditional spiritual practices, from witchcraft and the occult to tarot and psychic readings. This trend reflects a search for meaning and certainty in uncertain times, with the psychic industry booming as a result.
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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
00:17:12
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
00:17:28
longest ever. We don't know that. Some theories suggest very
00:17:33
short period of solidification, which are mostly like
00:17:36
petrographic, petrological, or petrochemical calculations.
00:17:40
But if you add any kind of dynamic instability, like tidal
00:17:43
effect, or more impact, or anything dynamic, that cooling
00:17:47
period has to become longer because you're not just cooling
00:17:50
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
00:17:58
any kind of instabilities going on in terms of Moon's orbit
00:18:01
around the Earth and any tidal motion and different things,
00:18:04
that cooling of the magma ocean can last maybe a couple of
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hundred million years.
00:18:09
And all of a sudden it's kind of biting into this bombardment
00:18:13
period where you say, hang on a minute, surely if that is that
00:18:17
long, then surely there should have been some impact happening
00:18:20
in that period as well. So kind of that's where the idea for
00:18:23
this modelling work came. Came to be.
00:18:25
So I've done a series of simulations that would kind of
00:18:29
mimic bombardment under the residues of magma ocean if you
00:18:33
will. So if there was partly solidified mantle, there is a
00:18:36
flotation crust on it and kind of sandwich layer of melt
00:18:40
between the crust and the mantle, then we're kind of
00:18:44
modeling late stages of solidification of the Moon.
00:18:47
And all the impacts that the simulations, these big impacts
00:18:51
that are run is... It's showing that because of that little
00:18:55
sandwiched layer of melt, that the crust ends up being squishy,
00:18:59
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.
00:19:40
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.
00:19:48
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.
00:19:59
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
00:20:06
look at Jupiter's moons, like Ganymede, for example, or even
00:20:11
Europa, but Europa has a lot of...
00:20:13
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
00:20:25
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.
00:20:34
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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