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This is Space Time, Series 28, Episode 117, for broadcast on
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the 29th of September, 2025. Coming up on Space Time,
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Stardust, older than the solar system, found in the asteroid
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Bennu. Strange and mysterious features discovered in Saturn's
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atmosphere. And the Parkas solar probe undertakes a close flyby
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of the Sun. All that and more coming up on Space Time.
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Welcome to Space Time with Stuart Gary.
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Scientists have discovered minerals older than our solar
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system, embedded in the asteroid Bennu. The findings, reported in
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the journal's Nature Astronomy and Nature Geoscience, could
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help explain how planets like the Earth first formed.
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The new research provides the most comprehensive analysis yet
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of samples from NASA's OSIRIS-REx mission, which
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returned more than 120 grams of pristine asteroid material from
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Bennu to Earth in 2023. One of the study's authors, Nick Timms
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from Curtin University, says the findings show the asteroid Bennu
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is composed of ancient cosmic material, including stardust,
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which is older than the solar system itself.
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The analysis indicates that the 490-metre-wide asteroid's parent
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body was built from a rich, varied mix of organic compounds,
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icy materials, silicates and grains from ancient stars,
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preserved in near-perfect conditions for more than four
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and a half billion years.
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Tim says some of these materials formed in other stars long
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before the solar system existed. Others formed in the outer solar
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system, and still others were condensed close to the Sun
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before being carried outwards.
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This means that asteroid Bennu's parent body must have been
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formed from dust from distinct regions of the solar system, or
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at least the protoplanetary disk which eventually would form our
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solar system, and then likely travelled from an orbit beyond
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Jupiter towards the inner solar system and the main asteroid
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belt.
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Some time later, the parent body was destroyed and some parts
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were reassembled into Bennu, a rubble pile asteroid which
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eventually drifted into its current near-Earth orbit. Tim
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says Bennu helps astronomers understand how planets form and
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how key ingredients, such as water and organic matter, may
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have reached the Earth.
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Some of the work involved looking at the small components
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that make up asteroid Bennu and it's basically quite a buffet
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of... Of all sorts of different particles from early in the
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solar system and even some tiny particles that formed before our
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solar system formed as well, which tells us about whereabouts
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in the solar system the parent body for asteroid Bennu was
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formed.
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And also we've been finding out a lot about the conditions on
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the parent body for the asteroid as well and how water was very
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instrumental in changing some of the components of the asteroid
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and altering things at conditions. Roughly around room
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temperature on the parent body for asteroid Bennu very, very
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early on in the solar system, long before it was smashed up
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and reassembled into a big rubble pile asteroid Bennu is
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today.
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So what can you tell us about the environment Bennu was formed
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in?
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Well, the asteroid was, or the parent to the asteroid at least,
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was kind of amalgamated or accreted from dust particles and
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ice particles from different parts in the solar system very
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soon after the Sun formed.
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And before really the planets got to form into the planets
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that we know today, we think there were lots more
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proto-planets or baby planets which started to creep from the
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dust in the solar disk in the early solar system. And some of
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those survived and accumulated today to what we know as the
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planets, and some of them didn't. And the parent body for
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asteroid Bennu was one of the early ones that didn't survive.
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But we found out some of the components were formed. In the
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inner solar system, and some of the parts of Bennu, the Bennu
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parent body, were accreted in the outer solar system. So there
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was lots of movement and mixing and migration of material in the
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early solar system to make up what we now see as asteroid
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Bennu.
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So how did you determine that? Was it simply that you looked at
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the composition of the water itself to see how much deuterium
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there was in it, or how is that done?
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So what we can do is look at, well, there are two things.
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Really two main ways of studying the asteroid material. One is to
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make measurements of larger pieces of it and look at the
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bulk geochemistry of those fragments. So it sort of
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amalgamates everything together to get a sort of a bulk view of
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what the average of everything is in all of the bits inside the
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asteroid material.
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And the other approach really is to look at the individual grains
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and individual crystals and fragments and particles within
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the asteroid material and try to fingerprint where they're from
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using a combination of geochemistry and isotope
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geochemistry. And it's the combination of those things that
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have helped sort of identify all of these different weak
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components.
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For example, the asteroid contains just a few percent of
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types of minerals which have escaped hydrothermal alteration
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of some of the original bit if you like, some of the original
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fragments, and the hydrosilicates, a group of
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minerals which include things like olivine, which you might
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know as peridote, which people put on jewelry, and a group of
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minerals called pyroxenes.
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Now, we could analyze those crystals individually and
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measure their oxygen isotope values, so the proportions of
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different isotopes of oxygen, so oxygen-16 and oxygen-17,
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oxygen-18, and that allows us to interpret. What their sources
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were. And some of them was really, really primitive
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material, primordial material formed right after the formation
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of the Sun, some of the earliest solids to form in the solar
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system.
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And some of those minerals have actually been processed, they've
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been remelted again, and are fragments of what we call
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chondrules, which are subject to sort of flash heating events in
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the early solar system as well. So that's just an example of how
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we can fingerprint some of the origins of some of the minerals
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in asteroid Bennu.
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Some of your colleagues were also able to find material in
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there that was from beyond our solar system, grains from
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stardust from interstellar origins.
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Yeah, that's exactly right. So a small team, a couple of groups
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around the world are able to look at the composition of
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really, really small particles that are very rare. They only
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exist, you know, a few tens of parts per million in the
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asteroid, which is very low abundance.
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But they're very conspicuous because they have extremely
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different. Isotope ratios in several different types of
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isotopes, including nitrogen and oxygen and so on and so forth,
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that really indicate that they can't have formed from the
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environment of our Sun and they have to have formed in different
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star systems.
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So they were into solar system or galactic dust that was around
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at the time of the formation of the solar system and then they
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got accreted or basically absorbed into these
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proto-planetary bodies. They got mopped up. As well.
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And some of them have survived the alteration, so we can
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analyze those and see back to what kind of star systems that
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they were formed in. It just gives us some indication of what
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sort of cosmic dust was around right at the beginning of our
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solar system in the environment that our Sun formed in.
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And one of the other surprising finds was that Bennu was a
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sibling to Ryugu, the other recent asteroid visited by a
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spacecraft for sample return.
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Yeah, that's right. So the Japanese space agency JAXA also
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returned samples from... An asteroid before. We had samples
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from the asteroid Bennu. The asteroid they returned samples
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from was called Ryugu. And both of the two asteroids are very,
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very similar in all of the types of particles that make them up
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and their isotopic and geochemical compositions.
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And so, in a sense, they're almost like sibling asteroids
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that have happened to have come in from the asteroid belt to
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near-Earth orbits and have had very, very similar histories.
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And probably formed in very, very similar regions of the
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solar system originally.
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And both asteroids were chosen by the different space agencies
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because they were very carbon-rich, and we wanted to
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sample some carbon-rich asteroids to look at the
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organics in both of those. And it turns out that they are very
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similar, which is quite phenomenal, really.
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I remember when the OSIRIS-REx mission landed on Bennu to gain
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samples, they discovered just how fluffy and little density it
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had.
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Yeah, so when Osiris Rex... Touchdown on asteroid Bennu
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after it was sort of hung around in orbit with it for the best
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part of two years. And they were taking incredibly detailed
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images of the asteroid so they can map it in detail, figure out
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a really good place to touch down, grab a sample and jet back
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off again.
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But nobody, I don't think anybody was expecting how soft
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the asteroid was. I've heard my colleagues describe that
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touchdown. It was almost like a probe sinking into a bowl of
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popcorn. It was, you know that's soft and they had to initiate
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thrusters actually to get the probe back out again before the
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spacecraft jetted back to Earth.
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So it was a really kind of exciting, intense moment and all
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of it captured with amazing video footage as well from the
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spacecraft that was relayed back to Earth and it's really quite,
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it's quite incredible. It was really good to see when we were
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part of the mission and that happened live as well. It was a
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really, really exciting time.
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That's Associate Professor Nick Timms from Curtin University.
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And this is Space Time. Still to come, strange and mysterious
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features discovered in Saturn's atmosphere. And NASA's Parker
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Solar Probe undertakes a close flyby of the Sun. All that and
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more still to come on Space Time.
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New observations from the Webb Space Telescope have uncovered
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mysterious, never-before-seen features in Saturn's atmosphere.
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The strange, complex structures of beads in a star-like pattern
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are unlike anything ever seen before on another planet. The
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findings were presented at the Europlanet Science Congress
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Division Of Planetary Sciences Conference in Helsinki, Finland.
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One of the study's authors, Tom Stellard from Northumbria
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University, says the findings came as a complete surprise.
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Stollard says astronomers expected to see emissions in
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broad bands at various atmospheric levels.
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But instead, the observations showed these fine-scale patterns
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of beads and a star that, despite being separated by huge
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distances in altitude, may somehow be interconnected and
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may even be linked to Saturn's famous North Pole hexagon. He
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says these features were completely unexpected and, at
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present, are impossible to explain.
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The patterns were discovered during a continuous 10-hour
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observation period using Webb back in November last year. The
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authors were focused on detecting emissions by a
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positively charged molecular form of hydrogen, which plays a
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key role in reactions in Saturn 's atmosphere, and so can
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provide valuable insights into the chemical and physical
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processes at work.
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Webb's near-infrared spectrograph allowed the authors
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to simultaneously observe hydrogen ions in the ionosphere.
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1 kilometers above Saturn's cloud tops, and methane
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molecules in the underlying stratosphere at an altitude of
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around 600 kilometers.
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In the electrically charged plasma of the ionosphere, the
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authors observed a series of dark bead-like features embedded
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in bright auroral halos. These structures remained stable for
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hours, but they appeared to drift slowly over longer
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periods. And around 500 kilometers lower, down in Saturn
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's stratosphere, the authors observed a strange asymmetric
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star-shaped feature.
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This unusual structure extended out from Saturn's North Pole
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towards the equator. But only four of the star's six arms were
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visible, with two mysteriously missing, in the process creating
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what appears to be a lopsided pattern. Saturn's upper
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atmosphere has proven to be incredibly difficult to study
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with missions and telescopes to date due to the extremely weak
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emissions from this region.
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But web sensitivity has revolutionized science's ability
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to observe these atmospheric layers, in the process revealing
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structures completely unlike anything ever seen before.
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The authors mapped the exact locations of these features,
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finding that they overlaid the same region of Saturn at
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different levels, with the star 's arms appearing to emanate
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from positions directly above the points of the storm cloud
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level polar hexagon. This all suggests that the processes that
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are driving the patterns may influence a column stretching
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right through Saturn's atmosphere.
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Stallard thinks that the dark beads may result from complex
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interactions between Saturn's magnetosphere and its rotating
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atmosphere, potentially providing new insights into the
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energy exchange which drives Saturn's aurora. The asymmetric
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star pattern suggests previously unknown atmospheric processes
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operating in Saturn's stratosphere, possibly linked to
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the hexagonal storm pattern observed deeper in the
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atmosphere.
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Tantalizingly, the darkest beads in the ionosphere appear to line
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up with the strongest star arm in the stratosphere, but it's
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not clear at this point whether they are actually linked or
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whether it's just a coincidence.
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While both features could have significant implications for
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understanding atmospheric dynamics on gas giants, more
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work is needed to provide explanations for the underlying
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causes. So the authors are now looking for additional time on
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Webb for follow-up observations. In order to further explore
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these mysterious features.
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And with Saturn currently at its equinox, which only occurs once
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every 15 Earth years, the structures may well change
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dramatically as Saturn's orientation to the Sun shifts
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and the northern hemisphere moves into autumn. This is Space
00:14:26
Time. Still to come, NASA's Parker Solar Probe undertakes a
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close flyby of the Sun, and later in the Science Report, a
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new study is confirmed.
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That people who remain virgins into adulthood tend to be less
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happy. All that and more still to come. On Space Time, NASA's
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Parker Solar Probe has just completed its 25th close
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approach to the Sun.
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This latest encounter matched the spacecraft's previous record
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distance of 6.2 million kilometres above the solar
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surface. The probe checked in with mission managers at Johns
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Hopkins Applied Physics Laboratory in L'Oreal, Maryland,
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two days after the close approach, using a series of
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coded beacon turns, indicating that its systems were all
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operating nominally.
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Parker was out of contact with the Earth and operating
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autonomously during the close flyby. A more detailed download
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of data will take place when the spacecraft moves further away
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from the Sun, out to an area where the star's intense ionized
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plasma radiation atmosphere will have less of an effect on
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communications.
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During the flyby, Parker also equaled its record-setting speed
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of 687 kmph, a Mark that, like the distance record, was
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set and subsequently matched during close approaches on
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December 24th last year and on March 22nd and June 19th this
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year. Parker will now remain in this orbit around the Sun and
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continue making observations.
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During these solar encounters, Parker's four scientific
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instrument packages are gathering unique observations
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from inside the Sun's atmosphere, the corona. The
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flyby allows the spacecraft to conduct unrivaled measurements
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of solar activity as the Sun goes through Solar Max, the peak
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of its 11-year solar cycle.
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The data being gathered includes observations of the solar wind,
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solar flares and coronal mass ejections, which are all
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critical. To help astronomers better understand geomagnetic
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storms. These drive high-energy space weather events, which can
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increase radiation exposure for crew in orbit on deep space
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missions and even people in high-altitude aircraft.
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The events can also damage or destroy spacecraft, or at least
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shorten the lifespans of satellites by causing Earth's
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atmosphere to expand, thereby increasing atmospheric drag,
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resulting in orbital decay, and forcing spacecraft to use more
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fuel in order to maintain their correct operational orbits.
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Solar storms also interrupt navigation and communication
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networks here on Earth, and they can trigger power grid
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overloads, which can cause terrestrial electricity
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blackouts affecting wide areas on the ground. This is Space
00:17:19
Time.
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Time now to take a brief look at some of the other stories making
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news in science this week with the Science Report. Well, in
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case you haven't worked it out yet, a new study has confirmed
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that people who remain virgins in adulthood are on average more
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nervous, more lonely and more unhappy. But the good news is
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they're also likely to be more educated and less likely to use
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alcohol or drugs.
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The findings reported in the journal PNAS analysed the traits
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of some 400 British virgins between the ages of 39 and 73,
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as well as some 13 Australian virgins aged 18 to
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89, in order to look for similarities among those who go
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well into adulthood without ever having had sex.
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The authors found common genetic variants explained about 17% of
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variation in sexlessness in men and 14% in women, although they
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stress there is no virgin gene. Links between genetics and
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behavior. Are too complex for that. But they did find that
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physical traits appeared to be far more strongly linked to
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virginity in men. Men were also more likely to be virgins if
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they lived in areas with fewer women.
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A widely reported study on apple cider vinegar and weight loss
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has now been retracted. The retracted research, reported in
00:18:53
the British Medical Journal, suggested that a small amount of
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apple cider vinegar every day may help overweight or obese
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people lose weight and reduce their body mass index.
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The small clinical trial received widespread
00:19:05
international attention when it was first published, and it
00:19:08
continues to be referenced by the media today. The retraction
00:19:11
comes after concerns were raised by critics of the study, which
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was then referred to statistical experts to evaluate its
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reliability.
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Not only were the statisticians unable to replicate the results,
00:19:22
but multiple analytical errors were also found. The British
00:19:26
Medical Journal also notes that there were irregularities in the
00:19:29
data set and the report. The authors say the errors were
00:19:32
honest mistakes, and they've agreed with the decision to
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retract the study.
00:19:38
Scientists have confirmed a new species of theropod dinosaur.
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They're the ones that look like T-Rex. Harquin rapticus sally
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was 7 meters long and weighed over 1 kilograms. The fossil
00:19:51
was found at a dig site in South America with a crocodile leg
00:19:54
bone in its jaws, suggesting it may well have been a top
00:19:58
predator when it was roaming the lands, and in this case the
00:20:00
shoreline, some 70 million years ago.
00:20:04
A report in the journal Nature Communications claims the new
00:20:06
species is part of a family of dinosaurs with powerful arms and
00:20:10
large claws which once lived across South America, Asia and
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Australia.
00:20:16
An investigative reporter with the New York Post has destroyed
00:20:20
the credibility of several paranormal true believers inside
00:20:23
the US government. Tim Mendham from Australian Skeptics says
00:20:27
the cutting takedown exposed several rogue military officials
00:20:31
and a few Washington politicians, some of whom even
00:20:34
believed they were being haunted by UFOs, ghosts and monsters
00:20:37
from Skinwalker Ranch.
00:20:39
There was quite a good video that came out recently, actually
00:20:41
on New York Post. There's a fellow there who does a lot of
00:20:43
investigations of the paranormal, and he's very good.
00:20:46
He does investigate properly. He looks at the evidence and goes
00:20:49
to places to see what happens.
00:20:51
Anyway, he was someone who was investigating in this recent
00:20:53
video UFOs and certain claims by UFOs that have had a high
00:20:58
profile lately, and also UFOs which often appear at a place
00:21:02
called Skinwalker Ranch in the US.
00:21:04
Now, the UFO claims, first of all, A number of people
00:21:07
appearing before Congress, putting their hand up and
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swearing this is true, that they were told by someone, the
00:21:11
brother-in-law of someone else, that the America and the
00:21:14
governments are covering up UFOs and that they're holding craft.
00:21:17
And listen, if the news is going to come out there any day now,
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which is something they've been saying for 70 years, literally
00:21:23
70 years, that any day now the evidence, the convincing
00:21:26
evidence is going to come out. It hasn't.
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There is nothing substantial in what they've said at all. No
00:21:31
evidence. Nothing. Then you move into the Skinwalker Ranch, which
00:21:34
is this place in America which was supposedly a center for UFO
00:21:38
activity, not to mention ghosts and all kinds of monsters and
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various things.
00:21:42
Skinwalkers have a place in Native American folklore, don't
00:21:45
they?
00:21:45
Yes, it's nice of them to appropriate that term and apply
00:21:49
it to a place which therefore gives it the imprimatur that it
00:21:51
's sort of an ancient heritage, strange things going on.
00:21:54
Skinwalkers were supposed to be someone who could take on the
00:21:56
form of an animal and therefore move unnoticed.
00:21:59
So they named this ranch Skinwalker Ranch. But it is this
00:22:01
place supposedly full of all sorts of paranormal encounters.
00:22:04
It's got TV shows they run. It's got a lot of publicity. The guys
00:22:08
running it obviously make a few bucks out of it. And this fellow
00:22:11
who did this...
00:22:11
It's a bit like finding Bigfoot, isn't it? They keep searching
00:22:13
for these mythical creatures and they never quite get there in
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time.
00:22:18
They just missed it. It was here yesterday. Yes. But, I mean, the
00:22:21
thing about This Skinwalker Ranch is it has a lot of
00:22:24
followers, high-profile followers and people who you
00:22:26
would hope would know better, including a lot of American
00:22:29
politicians.
00:22:29
Some of them went to Skinwalker Ranch and then claimed that they
00:22:32
were attacked by a ghost or something, which then followed
00:22:34
them back to where they came from. Skinwalkers in the Midwest
00:22:38
somewhere. These ghosts followed them back to the East Coast and
00:22:41
are still haunting them and annoying them. And you think
00:22:43
these are people making policy decisions about the most
00:22:45
important things in America.
00:22:47
I'll let you in on a little secret. Politicians really
00:22:49
aren't that bright. Believe me, I know. I know. I've met a lot
00:22:52
of them.
00:22:52
They're as easily fooled as anybody else. And there's still
00:22:56
no evidence of these things being there, of attacking
00:22:58
people. It's all gossip, rumour, publicity, you name it. None of
00:23:02
these things have ever shown any good evidence for them, but that
00:23:05
's never stopped them being popular.
00:23:06
That's Tim Mendham from Australian Skeptics.
00:23:24
And that's the show for now. Space Time is available every
00:23:28
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00:23:31
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00:23:46
Space Time is also broadcast through the National Science
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00:24:18
You've been listening to Spacetime with Stuart Gary. This
00:24:21
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