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STUART GARY: This is space time series 26 episode 88 for
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broadcast on the 24th of July 2023. Coming up on space time,
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astronomers discover a mysterious new type of stellar
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object hiding in plain sight. NASA's MARS Perseverance Rover
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samples an ancient Martian river bed. And the first Beppe Colombo
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fly by of the planet Mercury shows electron rain triggering
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x-ray aurora.
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All that and more coming up on space time.
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GENERIC: Welcome to space time with Stuart Garry.
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STUART GARY: Astronomers have discovered a mysterious new type
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of stellar object one which is challenging science's
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understanding of the physics of neutron stars and white dwarves.
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A report in the journal nature suggests this object could be an
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ultra long period magnetar, a rare type of neutron star with
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extremely powerful magnetic fields which can produce
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powerful bursts of energy.
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Problem is the evidence for that isn't quite adding up until
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recently, all known magnets released energy at intervals
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ranging from a few seconds to a couple of minutes.
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But this newly discovered object emits radio waves every 22
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minutes and that would make it the longest period magnet ever
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detected, put simply it's rotating far too slowly. To emit
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radio waves based on our current understanding of stellar
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physics. The object's been cataloged as GPM J 18 39 minus
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10, it's located 1500 light years away.
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So it's within our milky way galaxy and it's in the direction
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of the constellation Scutum. Astronomers discover this weird
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object using the Merche and wide field Array radio telescope in
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Outback, Western Australia.
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The study's lead author Dr Natasha Hurley Walker from the
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Curtin University node of the International Center For Radio
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Astronomy Research says if this is a type of neutron star
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magnet, then it challenges science's understanding of these
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objects which are already some of the most extreme and exotic
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stars in the universe. And amazingly, it's not the first of
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these objects to have been discovered.
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An earlier version was discovered by Curtin
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University's Tarana Doherty. Initially, scientists couldn't
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explain what they were seeing, describing it simply as an
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enigmatic transient object that would intimately appear and
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disappear, emitting powerful beams of energy three times an
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hour.
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So they started searching the skies using the Merson Widefield
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Array for similar objects in order to determine whether the
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first one was an isolated event or just the tip of the iceberg.
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And they soon found what they were looking for in the guise of
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GPM J 18 39 minus 10.
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Interestingly, this new object emits bursts of energy lasting
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up to five minutes which is five times longer than the first
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object, other telescopes including the CSIRO's Parkes
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radio telescope, the Australia telescope compact Array in Narra
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Bry and ASCAP.
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The Australia square kilometer Array pathfinder radio telescope
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were called into the search as was South Africa's Merca Array
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and the XMM Newton Space telescope. All employed to learn
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more about this object's unique characteristics now armed with
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GPM J 18 39 minus 10 celestial coordinates and characteristics.
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The authors also began searching the archives of other
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telescopes.
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And Hurley Walker says it showed up in observations by the giant
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meter wave radio telescope in India and the National Science
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Foundation's very large Array in New Mexico observations dating
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back as far as 1988. She says they failed to identify the
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object because no one had expected to find anything like
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it.
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So are we talking about a magneto or not? Well, the first
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thing to remember is not all magnetos produce radio waves and
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this object exists below the so called death line, a critical
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threshold where a star's magnetic field becomes too weak
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to generate high energy emissions.
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But simply this newly identified object is spinning way too
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solely to produce radio waves. It's below this death line. Now
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assuming it's a magnetar and that's still a big assumption at
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this stage. It shouldn't be possible for this object to
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produce radio waves, but that's exactly what the authors have
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been detecting every 22 minutes.
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It emits a five minute pulse of radio wavelength energy and it's
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been doing that for at least 33 years, this discovery has
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important implications, not just for science's understanding and
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the physics of neutron stars, but also the behavior of
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magnetic fields in extreme environments.
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It also raises new questions about the formation and
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evolution of magnets and could shed light on the origins of
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that mysterious phenomenon known as fast radio bursts.
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Right now, Hurley Walker and colleagues plan to conduct
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further observations of the magnetar in order to learn more
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about its properties and behavior. She says they also
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hope to discover more of these enigmatic objects in the future
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in order to determine whether they are indeed ultra long
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period Magne stars or something even stranger and more
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phenomenal.
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DR NATASHA HURLEY WALKER: So we've been searching the skies
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with the Merson wide field Array, which is the radio
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telescope here in Outback Western Australia. And yeah,
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we've found a strange repeating radio source. It produces pulses
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of radio waves that last for about five minutes each and they
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repeat every 22 minutes.
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And this is a little bit like a pulsar but slowed down by about
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a factor of 1000. And that's extremely unusual. You mentioned
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magnes per percent. Well, magnets are pulsars with very
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complicated magnetic fields.
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And we thought that perhaps a source like this could be a
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magnetar because the really strong magnetic field might give
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it enough energy to produce the radio waves, even though it's
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spinning as far as we can tell too slowly to do. So the thing
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is magnet stars should also be bright in the x-ray and also
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they should only produce radio waves for a few weeks or a few
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months. This source doesn't produce any x rays that we can
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tell.
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And it's been active for over 30 years. It was in the data about
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30 years ago, but nobody actually noticed until now. So
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the techniques that we've come up with in order to scan the
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skies using quite clever imaging techniques and the detection
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algorithms and powerful supercomputers to process all of
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that data.
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Those are the techniques that have allowed us to find these
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signals. And then when we applied them to the same patch
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of sky in data from older telescopes that have been
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running for a long time, that's when we started to find that the
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source has been there the whole time. But what we were missing
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30 years ago was the technique tell me about the patch of sky.
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It's in from our point of view, it's in the SCOT constellation,
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but in a kind of more zoomed out astronomical sound perspective,
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it's in our own milky way galaxy. So our solar system is
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one of hundreds of billions of systems all through our galaxy.
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That's what our galaxy is.
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It's a whole collection of stars and the source that we are
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looking at is right towards the middle of the galaxy a little
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bit to the west in terms of like galactic coordinates, we know
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it's about 15 light years away. For context, our whole
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galaxy is 40 to 80 light years across. So it's, it's kind
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of deep into the galaxy really quite far away.
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So it's amazing how luminous it must be to be so detectable by
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our radio telescope towards that part of the sky. You're sort of
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looking a little bit kind of left of the center of the
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galaxy. It actually is a bit of a challenge following it up in
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optical wavelengths. So, you know, we made the detection in
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radio and then we want to look with very powerful optical
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telescopes.
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But when you look towards that position, as they say, in 2001,
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my God taste, it's full of stars, it's completely crowded.
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There's just so many objects along that line of sight because
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you're looking right through the thickest part of the galaxy. It
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really challenging.
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STUART GARY: Is it a neighborhood where we find lots
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of starburst action going on or lots of large stars with short
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life spans that are likely to become neutron stars?
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DR NATASHA HURLEY WALKER: DR NATASHA HURLEY WALKER: That's
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a great question and not particularly, it's a little hard
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to tell because our distance probably has an error bar of
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about 5000 light years on it. So 15 light years away, plus or
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minus 5000, it's actually quite difficult to tell how far away
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sources detected in the radio are, especially when they're
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completely new. So we have no idea whether it's bright and far
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away or dim and relatively close.
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What we use to find the distance is that we pick up radio waves
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across many different frequencies. And the
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interstellar gas in our galaxy, the electrons in our galaxy,
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they actually make the low frequency waves appear just a
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little bit later, a few seconds later than the high frequency
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radio waves. This is a well known effect called dispersion.
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And if you roughly know how many electrons there are between you
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and another place in the galaxy, you can kind of work out the
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distance by seeing how slowed down those low frequencies are.
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So that's what we've used. But our, our knowledge of how many
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electrons there are is not certain enough to do more than
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it's about 15 light years away. We know it's not next
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door. Anyway, it's a.
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STUART GARY: Ball park figure. So no one said anything like
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this before. This is something new to science.
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DR NATASHA HURLEY WALKER: Well, the reason we were searching was
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because we discovered a source that repeated every 18 minutes
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and we published that last year also in nature. But the thing is
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with that source, it was only on for a few months. And that's a
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little bit easier to explain with that Magne theory.
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Perhaps just for a brief time, you have a neutron star that's a
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magnetic field all tangled and confused and that produces
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enough extra energy to overcome this very slow rotation rate.
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And still produce radio wave and then that's a little bit more
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explicable if it's only on for a short time.
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But the source has been on for 30 years. So it looks a lot like
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a normal pulsar but pulsars, like we thought, we understood
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them and we thought that once they started rotating about once
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a minute, maybe once every two minutes, there was just
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absolutely no way they could produce radio waves.
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And yet we're seeing them and we have been seeing them. So it's a
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real puzzle for the theorists. And that's again, why the
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discovery has been published in nature and why people are so
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excited about it.
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STUART GARY: What are the hypotheses going on about it?
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What are the sort of ideas you guys are coming up with as to
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what could be doing this?
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DR NATASHA HURLEY WALKER: Well, the theory still has as it were,
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people are working on that. There's also the possibility
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that it's a white dwarf. So a neutron star is when it occurs
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when a star that's sort of more massive than our sun ends its
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life and collapses. And that there's so much mass there that
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squashes everything into neutrons. The star that's about
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the mass of our own sun doesn't quite get there.
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It's not quite massive enough. So instead it ends its life as a
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white dwarf, which is basically all of the atoms are crushed
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together, but the protons and electrons don't recombine to
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form neutrons. So you have a big ball of very hot atoms. It's
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about the size of the Earth and it still has a mass of the sun
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in it.
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So it's a very big and massive and interesting object. The
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magnetic field, just like neutron stars, the magnetic
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fields get kind of concentrated. So there's a theory that a white
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dwarf could also produce radio emissions. The thing is we only
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know of a couple of white dwarfs that do produce radio emissions.
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Literally two, both of them are in very tight binaries as in
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they have a companion star that they orbit around the orbits
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with them every few hours. So they're very, very close to that
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star and they themselves rotate every couple of minutes. So
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they're still rotating much faster than our objects. So it's
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a little bit puzzling. It's one of the theories that's a little
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bit to be honest.
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I went to a big conference with basically experts in transient
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radio astronomers from all over the world. And I presented my
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work and my collaborators presented their work and
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everybody talked about all of the interesting objects that
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they found and all of the ways in which we think the radio
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mission is being generated.
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It was very exciting. And right at the end of the conference, I
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asked people to put up their hands. Do you think the long
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period radio transient are neutron stars, white dwarfs or
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something else? And the whole room is completely split.
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It was, there was about a third of each. So this is the world
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experts gathered in one place, having done nothing but talk
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about this and other radio phenomena for a week and they
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weren't sure either.
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So I think it's going to take the whole community and that's
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why I'm so excited that the paper is now out there so people
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can read it. And the best thing is this source is still on. So
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people can come up with new ways of observing it, point their
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telescope and then see what the data say, which I think.
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STUART GARY: We want to see if we can see this and see what's
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in its neighborhood if it's got a binary partner.
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DR NATASHA HURLEY WALKER: Yeah, that's right. And it's, as I
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say, it's in a crowded field. So I think you need something like
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JST. I think we'd probably do it very hard to get time on. But
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now that the papers out there may be a little bit easier and
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that would be really exciting.
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The other thing is I'm still working on finding new examples
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of this kind of thought, you know, clearly the design of the
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surveys that I've created and the techniques that I've used,
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they work. So now I just need to apply them to more data and
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maybe I can find one that's in a less crowded field. And I think
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that would be a good way of trying to figure out what these
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things really are now.
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STUART GARY: As well as looking at it with the Merch and white
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thought Array ASCAP was involved. So, to Meerkat XMM
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Newton played a part parks of the dish. What else was there?
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The narra radio telescope work? So, you've looked at this with a
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lot, seeing it so many different ways. Is there anything at all
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that's coming up that unusual in one particular wave band?
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DR NATASHA HURLEY WALKER: Yeah, I'm so glad you asked that
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because it's one of the things that people don't often often
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ask about and I think it's one of the most interesting, but
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it's a little tiny bit technical. So like, let's
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imagine you go to the beach and you've got some lovely polarized
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sunglasses and you're looking out over the water and you get
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that tremendous glare of the water.
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But when you pop your polarized sunglasses on all of that glare
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disappears, that's because the light waves that are coming from
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the sun reflecting off the water waves and going into your eyes,
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the reflective ones are all at a particular angle and your
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polarizes are designed to block that angle. But if you turn them
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to the side, then you get all of that glare coming through. So
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light can be polarized.
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Now, radio is just another form of light and it can also be
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polarized. So when we made observations with Merca and
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indeed ACA, they are sensitive enough and they have really
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beautiful polarization measurements that allow us to
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look the polarization of the source. And what we see is that
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for the most part, the pulses are polarized in a single
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direction.
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And every so often for just a few milliseconds that
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polarization completely swaps by like 90 degrees. It's as if you
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were, you were standing on the beach, you're wearing the
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polarized sunglasses and suddenly the whole ocean flashed
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a bright silver with the reflected sunlight just for a
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second. And you say what, what is going on? And I think that's
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a clue to something about the magnetic field of the source.
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Now, we only have a few of these observations. And so I have
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applied for more in order to find out well, more how often do
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these things occur? And what can that tell us about the magnetic
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field that's generating the radio emissions? So that's
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another really exciting line of research that we're working on
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and I hope we can catch some bright pulses. And that's Dr.
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STUART GARY: Natasha Hurley Walker from the Curtin
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University, note of the International Center For Radio
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Astronomy Research and this is space time still to come. NASA's
00:16:29
MARS Perseverance Rover takes its first sample from an ancient
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Martian riverbed and X ray aurora triggered by electron
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rains discovered on Mercury. All that and more still to come on
00:16:42
space time.
00:16:59
NASA's MARS Perseverance Rover has just collected its 20th core
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sample from the surface of the Red Planet. Mission managers are
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especially excited about this latest rock sample because it
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was drilled from an outcrop composed of tiny chunks of other
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rocks that were carried in river sediment from further upstream
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and eventually deposited on the floor of the river delta.
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Over billions of years, the sedimentary deposits became
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cement together. The new sample nicknamed Emerald Lake was
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collected from a location called Otis Peak on the 832nd soul or
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Ma's Day of the mission Perseverance project scientist
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Ken Farley from Caltech says conglomerates are like this
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pack.
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A lot of information about places the Rover may never
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visit. So each new rock fragment represents a new geologic story.
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He says, while the water that created the Martian river bed,
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that Perseverance is currently exploring evaporated billions of
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years ago. The story carried by those waters remains fresh,
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stored in the rocks.
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Perseverance is collecting these samples so that they can
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eventually be brought back to Earth by a joint NASA European
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Space Agency. MARS sample return mission once back home, they'll
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be studied by lab equipment too large and complex to bring to.
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MARS.
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Scientists will be able to study each pebble and fragment in the
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core sample in order to determine detail such as its
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age, what the environmental conditions were like in the
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river when the conglomerate was formed. And importantly whether
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it contains any sign of ancient microbial life. Remember the
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search for past life on the Red Planet is the primary objective
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of this mission.
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Now in its third science campaign. Perseverance is
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exploring the top of a fan shaped river delta of
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sedimentary rock stands about 40 m above the Jero crater floor
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with the sample now safely sealed and stored in its cache.
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The Rover is now on its way to a low ridge called snowdrift peak.
00:19:00
But in order to get there, it'll need to cross the field of
00:19:02
boulders as with the rock fragments of the Otis Peak
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sample. Scientists believe the boulders at snowdrift peak were
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likely formed elsewhere and then transported to their present
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location.
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Billions of years ago by the ancient river, boulders are also
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desirable of their large surface area that allows scientists to
00:19:22
visually investigate many potential distinct rocks in a
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single image. Fairley says whether the boulders appear
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intriguing enough for closer examination and even possible
00:19:32
sampling remains to be seen quite literally.
00:19:35
In this case, I guess you can say the science team are taking
00:19:39
a page from the past in days. Old prospectors looking for gold
00:19:43
or diamonds often looked into rivers and gullies in order to
00:19:47
determine whether there might have been any deposits further
00:19:49
upstream after all, why bother hiking there when you can let
00:19:54
the river do all the work? This is space time still to come.
00:20:00
The first Bibby Colombo fly by of the planet Mercury finds
00:20:03
electron rain triggering x ray aurora. And later in the science
00:20:08
report, a new study warns that most of the world's population
00:20:12
could be affected by polluted water by the year 2100. All that
00:20:16
and more still to come on space time.
00:20:35
The joint European Space Agency, Japanese Aerospace Exploration
00:20:40
Agency, Bee Colombo mission has discovered how electrons rain
00:20:44
down on the surface of the planet Mercury to trigger high
00:20:47
energy x-ray aurora. The mission which has been traveling to the
00:20:51
solar system's in immerse planet since 2018, successfully carried
00:20:55
out its first Mercury fly by back on the first of October
00:20:59
2021.
00:21:01
The new findings reported in the Journal Nature Communications
00:21:04
are based on observations made by the spacecraft during that
00:21:07
close encounter. A rural activity on Earth is generated
00:21:11
by interactions between the solar wind.
00:21:14
A stream of charged particles flowing out from the sun and an
00:21:17
electrically charged upper layer of the Earth's atmosphere called
00:21:20
the ionosphere. As Mercury only has a very thin atmosphere
00:21:24
called an exosphere. Its auroras are generated by the solar wind
00:21:28
interacting directly with the planet's surface.
00:21:31
The Beppe Colombo mission consists of three spacecraft
00:21:34
joined together and upper running as a single unit.
00:21:37
There's ESA's Mercury planetary orbiter, Jack's Mercury
00:21:41
magnetosphere orbiter and the cruise stage which provides
00:21:44
propulsion during the seven year journey to Mercury orbit
00:21:47
insertion.
00:21:48
During its first Mercury flyby, epi clumber swept to within 200
00:21:52
kilometers above the planet's surface. The observations by the
00:21:56
plasma instruments aboard the Mercury magnetosphere orbiter
00:21:59
enabled the first simultaneous observations of different kinds
00:22:03
of charged particles from the solar wind in the vicinity of
00:22:06
Mercury.
00:22:07
The study's lead author, Saya Zara from Jack's Institute Of
00:22:11
Space And Astronautical Science and the University Of Pisa says
00:22:15
the flyby allowed scientists to witness for the first time how
00:22:19
electrons are accelerated in Mercury's magnetosphere and
00:22:22
precipitate down to the planet's surface.
00:22:25
While Mercury's magnetosphere is much smaller than the Earth and
00:22:28
has a different structure and dynamics. The authors were still
00:22:31
able to confirm that the mechanism that generates aurora
00:22:34
is the same throughout the solar system.
00:22:37
During the flyby, maybe climber approached Mercury from the
00:22:40
right side of the northern hemisphere and made its closest
00:22:43
approach near the morning side of the southern hemisphere. It
00:22:47
observed the magnetosphere on the daytime side of the southern
00:22:50
hemisphere and then passed out of the magnetosphere back into
00:22:53
the solar wind.
00:22:55
Its instruments successfully observed the structure and
00:22:58
boundaries of the magnetosphere including the magnetic pores and
00:23:01
bow shock. The data also showed that Mercury's magnetosphere is
00:23:05
in an unusually compressed state most likely due to the high
00:23:09
pressure conditions in the solar wind.
00:23:12
The acceleration of electrons appears to occur due to plasma
00:23:15
processes. On the dawn side of Mercury's magnetosphere, the
00:23:19
high energy electrons are transported from the tail region
00:23:22
towards the planet where they eventually rain down onto the
00:23:25
planet's surface unimpeded by an atmosphere.
00:23:29
They interact with material on the surface and cause x rays to
00:23:32
be emitted resulting in the an auroral glow. Although aurora
00:23:36
have been observed in Mercury. Previously by NASA's Messenger
00:23:40
spacecraft, the processes triggering X ray fluorescence on
00:23:43
the surface had not been well understood or witnessed
00:23:46
directly. This report from ESA TV.
00:23:50
ESA TV: Images from the NASA Messenger mission are the best
00:23:53
we have of Mercury. NASA's Messenger mission did a great
00:23:57
job but be Colombo consists of two orbiters using complementary
00:24:03
orbits with more combined instruments. Plus unlike
00:24:08
Messenger, it will obtain high resolution images of the entire
00:24:13
planet. The planet is also shrinking in size, possibly due
00:24:18
to cooling. Plus there may be active volcanoes. So there is
00:24:22
much more to learn.
00:24:24
Mercury is a very mysterious planet. Every time we went
00:24:28
there, we found new surprising results. And that is the reason
00:24:33
why we do be Cola and we hope that be Cola. On one hand, we
00:24:36
are able to answer many of this new question, but I'm pretty
00:24:41
sure we found a lot of new surprising results which raise
00:24:46
new and other question which we then need to follow up.
00:24:50
It has highlands and lowlands like other planets. But unlike
00:24:54
Earth, Mercury rotates on an axis perpendicular to its orbit.
00:25:01
Due to the fact that Mercury is not tilted, there are some
00:25:04
craters on the poles where the sun never shines into it. And
00:25:10
inside these craters Messenger found water ice. It was detected
00:25:15
even earlier in the eight years from grounds that they were
00:25:18
rather bright spots.
00:25:20
And there were some hints that it might be water ice. But Now,
00:25:24
for Messenger, we are pretty sure that we have water ice in
00:25:27
craters and that's pretty much surprising. Think about if you
00:25:32
have a planet on the surface 450 degrees and then you have water
00:25:36
ice at the poles. It's kind of unbelievable.
00:25:40
Fortunately, there's an instrument on board called
00:25:43
Mertis, which can measure the surface temperature directly to
00:25:47
see if it's cold enough for water ice.
00:25:50
Knowing the makeup of the planet's dark surface is also
00:25:54
important. A team at DLR, the German Space Agency have built a
00:25:59
special chamber to heat up samples to examine how they
00:26:04
behave at high temperatures. These can then be compared with
00:26:08
what will be found on the planet.
00:26:11
Planetary scientists are unsure how it formed. It could have
00:26:15
originated beyond MARS with an impact, pushing it closer to the
00:26:20
sun or it could have formed at lower temperatures in its
00:26:24
current position. If so current theoretical models will need a
00:26:29
rethink.
00:26:31
And one of the things why I like working on Mercury is we need to
00:26:35
understand Mercury in order to understand how planets form. If
00:26:38
we have a model that forms all planets but not Mercury, that
00:26:43
model is basically useless because you need to get that one
00:26:46
as well.
00:26:47
Be Colombo arrives at the planet in 2025. Then for this joint
00:26:52
mission from ESA and the Japanese Space Agency, Jasa, it
00:26:56
will be time to unlock Mercury's mysteries.
00:27:00
STUART GARY: This is space time and time. Now to take a brief
00:27:19
look at some of the other stories making news in science.
00:27:22
This week. With the science report, a new study warns that
00:27:26
most of the world's population up to 5.5 billion people could
00:27:30
be affected by polluted surface water. By the turn of the
00:27:34
century.
00:27:35
The findings reported in the journal nature are based on new
00:27:38
computer modeling which shows that Sub Saharan Africa is
00:27:42
predicted to become a global hotspot for surface water
00:27:45
pollution.
00:27:45
By the year 2100 researchers used a high resolution global
00:27:50
surface water quality computer model to simulate water
00:27:53
temperature, indicators of salinity and organic and
00:27:57
pathogen pollution for the period from 2005 through to
00:28:00
2100. They found that poor surface water quality could
00:28:05
affect 5.5 billion people by 2100 and people living in
00:28:11
developing countries would be disproportionately affected.
00:28:15
A new study shows that new diagnoses of HIV, the human
00:28:20
immune deficiency virus that causes AIDS have stabilized in
00:28:23
Australia with 555 new cases. Last year.
00:28:28
The findings by the University Of New South Wales Kirby
00:28:31
Institute were released ahead of the 12th International Aids
00:28:34
Society Conference On HIV being held in Brisbane. The human
00:28:38
immune deficiency virus HIV is an infection that attacks the
00:28:42
body's immune system causing acquired immune deficiency
00:28:46
syndrome or AIDS.
00:28:48
It's thought to have originated from infected primates and
00:28:50
monkeys in western central Africa and was first identified
00:28:54
in humans in May 1981 when a large cohort of otherwise
00:28:58
healthy young biological males suddenly began dying from a
00:29:02
range of unusually rare diseases.
00:29:05
Hiv targets the body's white blood cells such as helper T
00:29:09
cells, specifically CD four plus T cells as well as macrophages
00:29:14
and dendritic cells weakening and causing the progressive
00:29:17
failure of the immune system.
00:29:19
This allows a wide range of opportunistic diseases such as
00:29:22
tuberculosis, several types of cancer to become critical,
00:29:26
eventually killing the patient HIV, spread from person to
00:29:30
person through body fluids, including blood, breast milk,
00:29:34
semen and vaginal fluids.
00:29:36
Early symptoms include fever, fatigue, headaches, a skin rash,
00:29:41
swollen, lymph nodes, aching muscles, joint pain, nausea,
00:29:45
vomiting, diarrhea, night sweats, a sore throat and a dry
00:29:49
cough.
00:29:50
The only known treatments for HIV involve powerful drug
00:29:54
cocktails known as antiretroviral therapy or art.
00:29:58
The World Health Organization estimates that up to 52 million
00:30:01
people have been killed by AIDS with another 40 million
00:30:05
currently living with HIV.
00:30:08
An analysis of ancient human genomic data suggests that
00:30:12
Copper Age farmers and step pastoralists may have interacted
00:30:16
1000 years earlier than previously thought. Researchers
00:30:20
analyzed genetic data from 135 ancient individuals from eight
00:30:24
sites across South Eastern Europe and the North Western
00:30:27
Black Sea region.
00:30:29
They found that while there was ge continuity between the
00:30:32
Neolithic and Copper Age groups from around 6.5 1000 years ago,
00:30:37
groups from the North Western Black Sea region carried varying
00:30:40
amounts of ancestry from Copper Age and step zone populations.
00:30:45
The findings, a report in the journal nature suggested the
00:30:48
groups had cultural contact and mixed nearly 1000 years earlier
00:30:52
than previously thought. And that the transfer of technology
00:30:56
between farmers and traditional hunters from different
00:30:59
geographical areas was important for the rise formation and
00:31:03
expansion of pastoral groups around 5300 years ago.
00:31:24
And that's the show for now. Spacetime is available every
00:31:27
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00:32:57
GENERIC: You've been listening to Space Time with Stuart Garry.
00:33:01
This has been another quality podcast production from bites
00:33:04
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