New Clues on Earth's Water Origins
A recent study published in the Proceedings of the National Academy of Sciences reveals that asteroid and comet impacts could only account for a small fraction of Earth's water supply. By analyzing oxygen isotopes in lunar regolith collected during the Apollo missions, researchers found that the early Earth likely retained little to no water during its formative years. This challenges long-held beliefs and suggests that the majority of Earth's water must have originated from other sources, rather than being delivered by celestial bodies.
Unprecedented Volcanic Activity on Io
NASA's Juno spacecraft has captured remarkable data on Io, the most volcanically active body in our solar system. Observations from a December flyby revealed the most energetic eruption ever detected on Io, affecting a vast area of 65,000 square kilometers. The findings indicate that interconnected magma reservoirs beneath Io's surface are responsible for this extraordinary volcanic activity, providing new insights into the moon's geological dynamics and evolution.
Tectonic Plates and Earth's Climate
A new study suggests that carbon released from shifting tectonic plates may have played a significant role in Earth's climatic transitions, rather than volcanic activity as previously thought. Researchers reconstructed carbon movements over the last 540 million years, providing evidence that carbon emissions from mid-ocean ridges were the primary drivers of climate shifts between ice ages and warmer periods. This research reshapes our understanding of past climate dynamics and offers valuable insights for future climate models.
www.spacetimewithstuartgary.com
✍️ Episode References
Proceedings of the National Academy of Sciences
Journal of Geophysical Research Planets
Communications Earth and Environment
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00:00:00 --> 00:00:02 Stuart Gary: This is space time series 29 episode
00:00:02 --> 00:00:05 14 full broadcast on the 2nd of uh, February
00:00:05 --> 00:00:08 2026. Coming up on Space Time,
00:00:09 --> 00:00:11 new clues about where Earth's water came
00:00:11 --> 00:00:14 from, fresh data about what really lies
00:00:14 --> 00:00:16 beneath the surface of the volcanic world of
00:00:16 --> 00:00:18 IO and how shifting tectonic
00:00:18 --> 00:00:21 plates may have driven planet Earth's
00:00:21 --> 00:00:23 climatic swings. All that and more coming
00:00:23 --> 00:00:25 up on Space Time.
00:00:27 --> 00:00:29 Welcome to Space Time with Stuart
00:00:29 --> 00:00:30 Gary Gary.
00:00:46 --> 00:00:49 A new study claims an analysis of the lunar
00:00:49 --> 00:00:51 surface is setting a hard limit on the amount
00:00:51 --> 00:00:53 of water which could have arrived on Earth as
00:00:53 --> 00:00:56 a result of asteroid or comet impacts.
00:00:56 --> 00:00:59 One hypothesis suggests that it condensed out
00:00:59 --> 00:01:01 of the same protoplanetary disk as the rest
00:01:01 --> 00:01:03 of the material that formed the early proto
00:01:03 --> 00:01:06 Earth 4.6 billion years ago. However, uh,
00:01:06 --> 00:01:09 another idea is that the early proto Earth
00:01:09 --> 00:01:12 would have been far too hot to retain any
00:01:12 --> 00:01:15 water. And so the water we wound up with
00:01:15 --> 00:01:17 today must have arrived later, probably
00:01:17 --> 00:01:20 carried in as a result of comet or asteroid
00:01:20 --> 00:01:22 impacts. Now a new study reported
00:01:23 --> 00:01:25 in the journal pnas, the Proceedings of the
00:01:25 --> 00:01:27 National Academy of Sciences, suggests that
00:01:27 --> 00:01:30 even given generous assumptions, comets and
00:01:30 --> 00:01:32 asteroids could only have ever supplied a
00:01:32 --> 00:01:34 small fraction of Earth's total water budget.
00:01:35 --> 00:01:37 The findings are based on a new analysis of
00:01:37 --> 00:01:40 oxygen isotopes in lunar regolith brought
00:01:40 --> 00:01:42 back to Earth by the Apollo Moon missions.
00:01:42 --> 00:01:45 The studies lead author Tony Gagano from the
00:01:45 --> 00:01:48 University of New Mexico says Earth has
00:01:48 --> 00:01:50 erased almost all of its early bombardment
00:01:50 --> 00:01:53 record through tectonics, erosion and
00:01:53 --> 00:01:55 constant crustal recycling. The Moon by
00:01:55 --> 00:01:58 contrast, preserves a continuous accessible
00:01:58 --> 00:02:01 archive, the lunar regolith, the loose
00:02:01 --> 00:02:03 layers of debris and dust produced and
00:02:03 --> 00:02:06 reworked by millions of impacts over billions
00:02:06 --> 00:02:09 of years. Ever since the Apollo
00:02:09 --> 00:02:11 missions, scientists have been trying to read
00:02:11 --> 00:02:13 that archive using elements that concentrate
00:02:13 --> 00:02:16 on impactors, especially metal loving
00:02:16 --> 00:02:18 siderophile elements, which are abundant in
00:02:18 --> 00:02:21 meteorites but scarce in the Moon's silicate
00:02:21 --> 00:02:24 crust. The problem is, regolith is an
00:02:24 --> 00:02:26 especially challenging mixture. Uh, impacts
00:02:26 --> 00:02:29 can melt, vaporize and rework material
00:02:29 --> 00:02:32 repeatedly. And then there are the post
00:02:32 --> 00:02:34 impact geological processes which can
00:02:34 --> 00:02:36 separate metal from silicate, complicating
00:02:36 --> 00:02:39 attempts to reconstruct the type and amount
00:02:39 --> 00:02:42 of impacted material. Gagano says
00:02:42 --> 00:02:44 put simply, the regolith on the lunar surface
00:02:44 --> 00:02:47 acts like a long term mixing layer. It
00:02:47 --> 00:02:50 captures impact debris, stirs it up and then
00:02:50 --> 00:02:52 preserves it together with new additions for
00:02:52 --> 00:02:55 immense spans of time. And this is why
00:02:55 --> 00:02:57 it's such a powerful archive. It lets
00:02:57 --> 00:02:59 scientists study what really is a time
00:02:59 --> 00:03:01 average record of what's been hitting the
00:03:01 --> 00:03:04 Earth Moon system. But instead of relying
00:03:04 --> 00:03:06 on metal loving traces, the new study looked
00:03:06 --> 00:03:09 at oxygen, the dominant element by mass in
00:03:09 --> 00:03:12 rocks, and specifically oxygen's triple
00:03:12 --> 00:03:14 isotope fingerprint, to separate two
00:03:14 --> 00:03:16 competing signals that normally get tangled
00:03:16 --> 00:03:19 together in lunar regolith, that is the
00:03:19 --> 00:03:21 addition of meteorite material and the
00:03:21 --> 00:03:23 isotopic effects from impact driven
00:03:23 --> 00:03:26 vaporization. By measuring offsets
00:03:26 --> 00:03:28 in the oxygen isotope composition of the
00:03:28 --> 00:03:30 regolith, the authors found that at least
00:03:30 --> 00:03:33 around 1% biomass of the regolith consists of
00:03:33 --> 00:03:36 impactor derived material that's best
00:03:36 --> 00:03:38 explained from carbon rich meteorites that
00:03:38 --> 00:03:40 were partially vaporized upon impact.
00:03:40 --> 00:03:43 Gagano says triple oxygen isotopes help
00:03:43 --> 00:03:45 distinguish impact of fingerprints from
00:03:45 --> 00:03:48 regolith that has a complicated history. So
00:03:48 --> 00:03:50 the authors were able to translate these
00:03:50 --> 00:03:52 impact diffractions into water delivery
00:03:52 --> 00:03:55 amounts. They then translated and multiplied
00:03:55 --> 00:03:58 these figures to fit the Earth. They
00:03:58 --> 00:04:00 found that even if planet Earth had
00:04:00 --> 00:04:02 experienced 20 times the impact of flux of
00:04:02 --> 00:04:04 the Moon, the total amount of water delivered
00:04:04 --> 00:04:07 to Earth by asteroid and comet impacts would
00:04:07 --> 00:04:09 only have amounted to just a few percent of
00:04:09 --> 00:04:10 an Earth ocean at most.
00:04:11 --> 00:04:14 Gagano says the main takeaway from this study
00:04:14 --> 00:04:17 is that Earth's water budget is hard, if not
00:04:17 --> 00:04:19 impossible to explain if one only considers
00:04:19 --> 00:04:22 water rich impactors from the outer solar
00:04:22 --> 00:04:24 system. Now, to be clear, the results
00:04:24 --> 00:04:26 don't say meteorites, asteroids and comets
00:04:26 --> 00:04:29 didn't deliver any water to the Earth, just
00:04:29 --> 00:04:31 that it could not have been very much,
00:04:31 --> 00:04:33 certainly not enough to have been the
00:04:33 --> 00:04:36 dominant source of planet Earth's oceans.
00:04:36 --> 00:04:39 This is space time. Still to come,
00:04:39 --> 00:04:41 fresh data about what lies beneath the
00:04:41 --> 00:04:44 surface of the volcanic world of IO and how
00:04:44 --> 00:04:47 shifting tectonic plates may be responsible
00:04:47 --> 00:04:50 for driving Earth's, uh, climatic swings. All
00:04:50 --> 00:04:53 that and more still to come on space time.
00:05:08 --> 00:05:11 NASA's Juno spacecraft has observed an
00:05:11 --> 00:05:14 unprecedented volcanic event on the Jovian
00:05:14 --> 00:05:17 moon IO which has provided new insights into
00:05:17 --> 00:05:19 what goes on, um, beneath the Ionian surface.
00:05:20 --> 00:05:23 IO is the most volcanically active world in
00:05:23 --> 00:05:26 our solar system. Whereas other places have
00:05:26 --> 00:05:29 weather reports, IO has volcanism reports
00:05:29 --> 00:05:31 with fresh eruptions taking place in, say,
00:05:31 --> 00:05:34 the northwest, lava flows increasing in the
00:05:34 --> 00:05:36 south and fresh magma lakes forming in the
00:05:36 --> 00:05:39 east. Now, new observations taken
00:05:39 --> 00:05:42 by the Juno spacecraft during a close flyby
00:05:42 --> 00:05:44 of IO in December witnessed the most
00:05:44 --> 00:05:46 energetic eruption ever detected on, um, this
00:05:46 --> 00:05:49 3 kilometer wide moon.
00:05:50 --> 00:05:52 The findings reported in the Journal of
00:05:52 --> 00:05:54 Geophysical Research Planets describes an
00:05:54 --> 00:05:57 eruption which affected an extremely vast
00:05:57 --> 00:06:00 area, some 65 square
00:06:00 --> 00:06:02 kilometres in part of the Moon's southern
00:06:02 --> 00:06:05 hemisphere. The observations by the
00:06:05 --> 00:06:07 Juno spacecraft's Jovian Infrared Auroral
00:06:07 --> 00:06:10 Mapper indicate an energy release of between
00:06:10 --> 00:06:13 140 and 260 terawatts,
00:06:13 --> 00:06:16 a value that far exceeds those of the most
00:06:16 --> 00:06:18 significant eruptions previously observed on
00:06:18 --> 00:06:20 IO. The study's lead author, UH
00:06:20 --> 00:06:22 Alessandro M. Mura from the Italian National
00:06:22 --> 00:06:25 Institute for Astrophysics, says what made
00:06:25 --> 00:06:27 this event even more extraordinary was that
00:06:27 --> 00:06:30 it didn't involve a single volcano, but
00:06:30 --> 00:06:32 multiple active sources that all lit up
00:06:32 --> 00:06:34 simultaneously, increasing their brightness
00:06:34 --> 00:06:36 by more than a thousand times compared to
00:06:36 --> 00:06:39 typical levels. This perfect
00:06:39 --> 00:06:41 synchrony suggests that it must have been a
00:06:41 --> 00:06:43 single enormous eruptive event propagating
00:06:43 --> 00:06:46 through the subsurface for hundreds of
00:06:46 --> 00:06:48 kilometers. The results
00:06:48 --> 00:06:50 suggest the existence of what must be
00:06:50 --> 00:06:53 enormous interconnected magma reservoirs deep
00:06:53 --> 00:06:56 beneath IO's surface, reservoirs capable
00:06:56 --> 00:06:58 of being activated simultaneously and
00:06:58 --> 00:07:01 producing planetary scale energy release.
00:07:02 --> 00:07:04 Muira says the observations provide direct
00:07:04 --> 00:07:07 evidence that IO's volcanism is being powered
00:07:07 --> 00:07:10 by deep interconnected magmatic systems.
00:07:10 --> 00:07:13 At the same time, other nearby volcanoes
00:07:13 --> 00:07:15 weren't involved in the eruption, adding
00:07:15 --> 00:07:17 unexpected elements of complexity to the
00:07:17 --> 00:07:20 functioning of IO's interior. Future
00:07:20 --> 00:07:22 observations may reveal whether the eruption
00:07:22 --> 00:07:25 left new lava flows or ash deposits on the
00:07:25 --> 00:07:27 Ionian surface. And that would provide
00:07:27 --> 00:07:30 further clues about the Moon's geological
00:07:30 --> 00:07:32 evolution and the very nature of its extreme
00:07:32 --> 00:07:35 volcanism. This is space
00:07:35 --> 00:07:37 time still to come. Our, uh, shifting
00:07:37 --> 00:07:40 tectonic plates may have driven planet
00:07:40 --> 00:07:42 Earth's climatic swings. And later in the
00:07:42 --> 00:07:45 Science report, scientists detect traces
00:07:45 --> 00:07:48 of Chinese radioactive nuclear waste, which
00:07:48 --> 00:07:50 has traveled all the way down into the West
00:07:50 --> 00:07:52 Philippine Sea. All that and more still to
00:07:52 --> 00:07:54 come on, um, space time.
00:08:10 --> 00:08:12 A new study claims that carbon released by
00:08:12 --> 00:08:15 the Earth's spreading tectonic plates may
00:08:15 --> 00:08:17 have triggered major transitions between the
00:08:17 --> 00:08:20 planet's ancient ice ages and warmer climates
00:08:20 --> 00:08:23 rather than volcanic activity as previously
00:08:23 --> 00:08:26 hypothesized. The findings reported in
00:08:26 --> 00:08:28 the journal Communications Earth and
00:08:28 --> 00:08:30 Environment, reconstructed how carbon moved
00:08:30 --> 00:08:33 between volcanoes, oceans and deep within the
00:08:33 --> 00:08:36 Earth's mantle over the last 540 million
00:08:36 --> 00:08:38 years. The study's lead author, Ben
00:08:38 --> 00:08:40 Mather from the University of Melbourne, says
00:08:40 --> 00:08:43 the findings challenge a long held view that
00:08:43 --> 00:08:45 change the volcanoes formed by colliding
00:08:45 --> 00:08:48 tectonic plates were Earth's main natural
00:08:48 --> 00:08:51 source of atmospheric carbon. In fact, the
00:08:51 --> 00:08:54 study shows that carbon gas released from
00:08:54 --> 00:08:56 gaps and ridges deep under the ocean from
00:08:56 --> 00:08:59 moving tectonic plates was instead likely
00:08:59 --> 00:09:02 driving major shifts between icehouse and
00:09:02 --> 00:09:04 greenhouse climates for most of Planet
00:09:04 --> 00:09:07 Earth's history. Mathers says his
00:09:07 --> 00:09:10 team found that carbon emitted from volcanoes
00:09:10 --> 00:09:12 around the Pacific Ring of Fire, for example,
00:09:12 --> 00:09:14 only became a major carbon source in the last
00:09:14 --> 00:09:17 100 million years, which challenges current
00:09:17 --> 00:09:20 scientific understanding. The work provides
00:09:20 --> 00:09:22 the first clear long term evidence that the
00:09:22 --> 00:09:24 global climate was shaped mainly by carbon
00:09:24 --> 00:09:26 released where tectonic plates pull apart
00:09:27 --> 00:09:29 rather than where they collide. The new
00:09:29 --> 00:09:31 insight not only reshapes science's
00:09:31 --> 00:09:34 understanding of past climates, but also
00:09:34 --> 00:09:36 helps refine future climate models.
00:09:36 --> 00:09:39 By pairing global plate tectonic
00:09:39 --> 00:09:41 reconstructions with carbon cycle modeling,
00:09:41 --> 00:09:43 the authors were able to trace how carbon was
00:09:43 --> 00:09:45 stored, released, and then recycled as
00:09:45 --> 00:09:48 continents shifted. The new findings help
00:09:48 --> 00:09:51 explain key historical climate shifts,
00:09:51 --> 00:09:53 including the Late Paleozoic ice age, the
00:09:53 --> 00:09:56 warm Mesozoic greenhouse world, and the
00:09:56 --> 00:09:58 emergence of the modern Cenozoic ice house.
00:09:59 --> 00:10:01 This shows how changes in carbon released
00:10:01 --> 00:10:04 from spreading plates shape these long term
00:10:04 --> 00:10:06 transitions to the planet's climate. Mathers
00:10:06 --> 00:10:09 says understanding how Earth controlled its
00:10:09 --> 00:10:12 climate in the past highlights how unusual
00:10:12 --> 00:10:14 the present rate of climate change really is.
00:10:15 --> 00:10:17 Jonathan Nally: Yeah, so one of the questions we had
00:10:17 --> 00:10:20 going into this research was to work out what
00:10:20 --> 00:10:22 are the main emitters of
00:10:23 --> 00:10:26 carbon, or CO2 throughout Earth's
00:10:26 --> 00:10:29 history. And one of the big findings was
00:10:29 --> 00:10:31 essentially that arc volcanoes. This is where
00:10:31 --> 00:10:33 oceanic plates get subducted under
00:10:34 --> 00:10:36 continental lithosphere, such as around the
00:10:36 --> 00:10:38 Ring of Fire in the Pacific Ocean. These arc
00:10:38 --> 00:10:41 volcanoes emit a whole bunch of carbon
00:10:41 --> 00:10:44 today. But if you go looking
00:10:44 --> 00:10:47 back through time based on our modeling, we
00:10:47 --> 00:10:50 actually find that they decrease in emissions
00:10:50 --> 00:10:53 quite rapidly until we get to about 100
00:10:53 --> 00:10:55 million years ago during the Late Cretaceous.
00:10:55 --> 00:10:58 So actually in mid ocean ridges, these are
00:10:58 --> 00:11:00 the cracks along the sea floor where
00:11:00 --> 00:11:03 tectonic plates split apart, are actually the
00:11:03 --> 00:11:06 main emitters of CO2 preceding the last
00:11:06 --> 00:11:07 hundred million years.
00:11:07 --> 00:11:08 Stuart Gary: It's interesting because one would have
00:11:08 --> 00:11:11 thought a similar sort of process with
00:11:11 --> 00:11:13 volcanic activity and uh, magma moving up
00:11:13 --> 00:11:16 from the mantle into the mid ocean ridges,
00:11:16 --> 00:11:17 then seafloor spreading that would have been
00:11:17 --> 00:11:19 going on long before that. And roughly the
00:11:19 --> 00:11:20 same sort of rates.
00:11:20 --> 00:11:23 Jonathan Nally: They roughly have, ah, actually the amount
00:11:23 --> 00:11:25 of CO2 that they emit is generally
00:11:25 --> 00:11:28 proportional to the rate of
00:11:28 --> 00:11:31 spreading. So the rate that the continents
00:11:31 --> 00:11:34 are being split apart and essentially how
00:11:34 --> 00:11:37 long that boundary is, so how, how
00:11:38 --> 00:11:41 many uh, mid ocean ridge segments there are
00:11:41 --> 00:11:44 on the Earth at any one time period. What the
00:11:44 --> 00:11:46 difference is is that the arc volcanoes
00:11:47 --> 00:11:49 at, uh, subduction zone, like the Ring of
00:11:49 --> 00:11:52 Fire, these arc volcanoes have really ramped
00:11:52 --> 00:11:55 up their emissions of CO2. And the
00:11:55 --> 00:11:58 reason for that is because we have a
00:11:58 --> 00:12:01 huge increase in the amount of
00:12:01 --> 00:12:03 deep sea sedimentary carbon that gets
00:12:03 --> 00:12:05 recycled into the uh, Earth and eventually
00:12:06 --> 00:12:08 spewed out these volcanic arcs.
00:12:08 --> 00:12:09 Stuart Gary: Okay, do we know why?
00:12:10 --> 00:12:12 Jonathan Nally: Because of these little critters
00:12:13 --> 00:12:15 called phytoplankton, which evolved some
00:12:15 --> 00:12:18 150 billion years ago and These
00:12:18 --> 00:12:21 have calcium carbonate scales and
00:12:21 --> 00:12:24 proliferated the Earth's oceans around 150
00:12:24 --> 00:12:26 million years ago. And when these plankton
00:12:26 --> 00:12:29 die, they leave immense deposits of calcium
00:12:29 --> 00:12:31 carbonate on the sea floor. And as the
00:12:31 --> 00:12:34 tectonic plates move and are eventually
00:12:34 --> 00:12:36 recycled into the Earth's, uh, molten
00:12:36 --> 00:12:39 interior by slipping under each other through
00:12:39 --> 00:12:42 subduction, these huge reservoirs of stored
00:12:42 --> 00:12:44 carbon end up being pushed into the mantle
00:12:44 --> 00:12:46 and then a portion of that carbon, ah,
00:12:47 --> 00:12:50 leaves the seducting ocean plate
00:12:50 --> 00:12:52 and will get mixed into the molten interior.
00:12:52 --> 00:12:54 But a portion of that will also get emitted
00:12:54 --> 00:12:57 via, uh, volcanic arc volcanoes. So
00:12:57 --> 00:12:59 yeah, it's really, it's really um, these
00:12:59 --> 00:13:01 critters that have evolved in the last 150
00:13:01 --> 00:13:04 million years ago which have resulted in
00:13:04 --> 00:13:06 volcanic arcs being the primary emitter of
00:13:06 --> 00:13:07 CO2 today.
00:13:07 --> 00:13:10 Stuart Gary: It's amazing that tiny microscopic animals
00:13:10 --> 00:13:13 and plants that one barely sees, other than
00:13:13 --> 00:13:15 the general greenness of the ocean, can make
00:13:15 --> 00:13:17 such consequential changes to the entire
00:13:17 --> 00:13:17 planet.
00:13:17 --> 00:13:20 Jonathan Nally: It is, isn't it? Yes, yeah. And this is a,
00:13:20 --> 00:13:22 uh, uh, key evidence of biological
00:13:22 --> 00:13:25 changes that go on within the Earth having a
00:13:25 --> 00:13:27 huge effect on the global deep
00:13:27 --> 00:13:30 carbon cycle. And previously to this
00:13:30 --> 00:13:33 research it wasn't really well understood
00:13:33 --> 00:13:36 exactly how much carbon these little critters
00:13:36 --> 00:13:38 can produce on the sea floor. But yeah,
00:13:38 --> 00:13:41 through this research we were able to
00:13:41 --> 00:13:43 essentially track the movement
00:13:43 --> 00:13:46 of carbon between the seafloor and
00:13:46 --> 00:13:49 the Earth's, uh, molten interior and the
00:13:49 --> 00:13:51 atmosphere which form this, I guess, deep
00:13:51 --> 00:13:53 time carbon cycle.
00:13:53 --> 00:13:55 Stuart Gary: Tell me how you did the research.
00:13:55 --> 00:13:58 Jonathan Nally: So a lot of the research that I do
00:13:58 --> 00:14:01 is to try and reconstruct Earth history
00:14:01 --> 00:14:04 using plate reconstruction. So that's uh, how
00:14:04 --> 00:14:07 the tectonic plates all fitted together at
00:14:07 --> 00:14:09 any time before the present day essentially.
00:14:09 --> 00:14:11 So we're looking, in this research, we're
00:14:11 --> 00:14:14 looking at the last 540 million years, but
00:14:14 --> 00:14:17 we have plate reconstructions now which go
00:14:17 --> 00:14:20 to 1.8 billion years ago.
00:14:20 --> 00:14:23 And now things get a little bit sketchy the
00:14:23 --> 00:14:25 further back you go. And the reason for that
00:14:25 --> 00:14:27 is because we have fewer and fewer uh,
00:14:27 --> 00:14:30 observations and evidence to go into these
00:14:30 --> 00:14:32 plate reconstructions. But nonetheless we
00:14:32 --> 00:14:34 have some plate reconstruction, some ideas
00:14:34 --> 00:14:37 and hypotheses of how the earth, uh, looked
00:14:37 --> 00:14:39 1.8 billion years ago. In this research, what
00:14:39 --> 00:14:42 we were able to do for the last 540 million
00:14:42 --> 00:14:45 years ago was couple these tectonic
00:14:45 --> 00:14:47 plates with a model of how carbon
00:14:48 --> 00:14:51 moves with the Earth. So we
00:14:51 --> 00:14:53 were able to track how fast tectonic plates
00:14:53 --> 00:14:56 spread apart, how fast they, ah, come
00:14:56 --> 00:14:58 together, and the length of those mid ocean
00:14:58 --> 00:15:01 ridges and subduction zones to try and work
00:15:01 --> 00:15:03 out how much carbon is being
00:15:03 --> 00:15:06 emitted and recycled back into the earth.
00:15:06 --> 00:15:09 Stuart Gary: Uh, they say pilots want to fly into space.
00:15:09 --> 00:15:12 Do uh, people studying mid ocean ridges want
00:15:12 --> 00:15:13 to go down and look at black smokers?
00:15:13 --> 00:15:16 Jonathan Nally: Yes. Well you can actually have an
00:15:16 --> 00:15:18 opportunity to look at an active mid ocean
00:15:18 --> 00:15:21 ridge in Iceland. So Iceland is
00:15:21 --> 00:15:24 a rare example where you can actually put on
00:15:24 --> 00:15:27 your scuba tank and uh, journey
00:15:27 --> 00:15:28 into a mid ocean ridge.
00:15:28 --> 00:15:30 Stuart Gary: There are parts of Iceland where you can
00:15:30 --> 00:15:32 actually be standing on two different plates,
00:15:32 --> 00:15:34 plates at the same time without having to get
00:15:34 --> 00:15:34 your feet wet.
00:15:35 --> 00:15:37 Jonathan Nally: Yes, that's, that's the much um, warmer
00:15:37 --> 00:15:38 option I'd say.
00:15:38 --> 00:15:40 Stuart Gary: That's Dr. Ben Mather, uh, from the
00:15:40 --> 00:15:43 University of Melbourne. And this is space,
00:15:43 --> 00:15:43 time.
00:15:59 --> 00:16:01 And time. Now to take a brief look at some of
00:16:01 --> 00:16:03 the other stories making news in science this
00:16:03 --> 00:16:04 week with the Science Report.
00:16:05 --> 00:16:08 A new study claims climate change made the
00:16:08 --> 00:16:11 intense January heat waves in Australia five
00:16:11 --> 00:16:14 times more likely. The findings by Imperial
00:16:14 --> 00:16:16 College London also show that the heat waves
00:16:16 --> 00:16:18 happened against a backdrop of a weak La
00:16:18 --> 00:16:20 Nina, which usually brings far milder
00:16:20 --> 00:16:22 temperatures to much of eastern Australia.
00:16:23 --> 00:16:26 Across southeastern Australia, maximum
00:16:26 --> 00:16:28 temperatures during January were consistently
00:16:28 --> 00:16:31 above 40 degrees Celsius. The area
00:16:31 --> 00:16:33 sweltering through its hottest temperatures
00:16:33 --> 00:16:35 since the infamous Black summer of 2019.
00:16:36 --> 00:16:38 2020. In Melbourne, temperatures often
00:16:38 --> 00:16:41 top 44 degrees, with hospitals reporting
00:16:41 --> 00:16:43 emergency admissions were up by as much as
00:16:43 --> 00:16:46 25%. While Port Augusta in
00:16:46 --> 00:16:49 South Australia was just one of many outback
00:16:49 --> 00:16:50 communities where temperatures reached more
00:16:50 --> 00:16:53 than 50 degrees Celsius, making them among
00:16:53 --> 00:16:56 the hottest places in the world. All
00:16:56 --> 00:16:59 that heat triggered devastating wildfires
00:16:59 --> 00:17:01 across Victoria, leading to a state of
00:17:01 --> 00:17:04 disaster being declared. The new analysis
00:17:04 --> 00:17:06 shows that in today's climate, Australia can
00:17:06 --> 00:17:09 now expect to experience similar heat wave
00:17:09 --> 00:17:11 conditions roughly once every five years.
00:17:13 --> 00:17:15 Doctors have breathed a sigh of relief after
00:17:15 --> 00:17:18 successfully keeping a patient alive for 48
00:17:18 --> 00:17:21 hours without lungs. The medical marvel
00:17:21 --> 00:17:23 reported in the Journal Med used an
00:17:23 --> 00:17:25 artificial lung system to help a 33 year old
00:17:25 --> 00:17:28 patient breathe for two days after he
00:17:28 --> 00:17:30 required both his lungs to be removed as a
00:17:30 --> 00:17:33 complication of a severe flu infection. The
00:17:33 --> 00:17:35 man's lungs had deteriorated rapidly due to
00:17:35 --> 00:17:38 bacterial pneumonia. So the surgeons
00:17:38 --> 00:17:40 decided to, on the spot, engineer an
00:17:40 --> 00:17:42 artificial lung system that pumped out the
00:17:42 --> 00:17:45 blood, removed carbon dioxide from it and
00:17:45 --> 00:17:47 then filled it with fresh oxygen before
00:17:47 --> 00:17:49 returning it to the patient, bypassing the
00:17:49 --> 00:17:51 need for physical lungs. The man was then
00:17:51 --> 00:17:53 able to spend two days recovering from the
00:17:53 --> 00:17:55 infection, which the medical team says was
00:17:55 --> 00:17:57 enough time for him to become stable enough
00:17:57 --> 00:17:59 for a double lung transplant. And now, more
00:17:59 --> 00:18:01 than two years later, the patient has
00:18:01 --> 00:18:03 returned to daily life with good lung
00:18:03 --> 00:18:04 function.
00:18:05 --> 00:18:08 Scientists have detected Chinese radioactive
00:18:08 --> 00:18:10 nuclear waste, which has traveled all the way
00:18:10 --> 00:18:13 down to the West Philippine Sea. The
00:18:13 --> 00:18:15 findings by the Philippine Nuclear Research
00:18:15 --> 00:18:17 Institute, the University of the Philippines
00:18:17 --> 00:18:20 and the University of Tokyo found higher
00:18:20 --> 00:18:23 levels of radioactive iodine129 in
00:18:23 --> 00:18:25 local seawater samples off the Philippine
00:18:25 --> 00:18:27 coast. Scientists tested 119
00:18:27 --> 00:18:29 samples from different parts of Philippine
00:18:29 --> 00:18:32 waters, finding that iodine 129 levels in the
00:18:32 --> 00:18:35 West Philippine Sea were between 1.5 and
00:18:35 --> 00:18:38 1.7 times higher than in nearby regions.
00:18:38 --> 00:18:41 This isotope is commonly produced by nuclear
00:18:41 --> 00:18:43 reactors and by thermonuclear weapons
00:18:43 --> 00:18:45 testing. The authors say the contamination
00:18:45 --> 00:18:47 was carried by ocean currents from the Yellow
00:18:47 --> 00:18:50 Sea area on the Chinese coast there.
00:18:50 --> 00:18:53 Chinese nuclear fuel reprocessing plants and
00:18:53 --> 00:18:56 leftover contamination from Cold War nuclear
00:18:56 --> 00:18:58 tests probably released the radioactivity
00:18:58 --> 00:19:00 into the rivers, which then poured it into
00:19:00 --> 00:19:02 the Yellow Sea and from there into the
00:19:02 --> 00:19:05 world's oceans. A new
00:19:05 --> 00:19:08 hypothesis claims pareidolia may be linked to
00:19:08 --> 00:19:11 a rare neurological condition which can cause
00:19:11 --> 00:19:13 a constant type of visual static in some
00:19:13 --> 00:19:16 people. The skeptics Tim Mendham says if
00:19:16 --> 00:19:18 proven correct, that the idea might offer a
00:19:18 --> 00:19:21 unique window into how an overactive brain
00:19:21 --> 00:19:23 may amplify erroneous illusionary patterns it
00:19:23 --> 00:19:24 sees.
00:19:24 --> 00:19:27 Tim Mendham: Pareidolia is the, um, phenomenon of seeing
00:19:27 --> 00:19:29 shapes, familiar shapes in surfaces, in
00:19:29 --> 00:19:32 clouds, in trees, whatever, seeing certain
00:19:32 --> 00:19:34 shapes, figures in those things. And the most
00:19:34 --> 00:19:36 common one is faces, because we're so used to
00:19:36 --> 00:19:38 seeing faces that that becomes just part and
00:19:38 --> 00:19:41 parcel. Um, use faces in toast, faces on the
00:19:41 --> 00:19:44 front of cars, taps. We are ready to see two
00:19:44 --> 00:19:46 eyes and a mouth and perhaps a nose as well.
00:19:46 --> 00:19:48 Everywhere that's face pareidolia. But
00:19:48 --> 00:19:50 pareidol is generally saying, we're actually.
00:19:50 --> 00:19:52 Stuart Gary: Wired to do that, aren't we? That was a
00:19:52 --> 00:19:54 survival technique of our ancestors.
00:19:54 --> 00:19:55 Tim Mendham: That's right. I mean, the face is the thing
00:19:55 --> 00:19:57 because you see it so much as a baby, for
00:19:57 --> 00:19:58 example, people staring at you, you know,
00:19:58 --> 00:20:00 faces. So you get used to faces, happy faces,
00:20:00 --> 00:20:03 sad faces, whatever. But yes, we are wired to
00:20:03 --> 00:20:05 find shapes, to try and find patterns where
00:20:05 --> 00:20:07 the patterns don't necessarily exist. So it
00:20:07 --> 00:20:08 gives us some sort of stability, if you like.
00:20:08 --> 00:20:10 A theory that's been put forward lately is
00:20:10 --> 00:20:13 that people who are suffering from Visual
00:20:13 --> 00:20:15 Snow Syndrome are more likely to have
00:20:15 --> 00:20:18 pareidolia experiences than those who don't.
00:20:18 --> 00:20:20 Now, Visual Snow syndrome is basically static
00:20:20 --> 00:20:22 in how you see things. There's a lot of dots
00:20:22 --> 00:20:25 in front of your eyes that confuse the image
00:20:25 --> 00:20:27 somewhat. Now there's an Obvious problem here
00:20:27 --> 00:20:29 that if people suffering from visual snow
00:20:29 --> 00:20:31 syndrome should have a less
00:20:31 --> 00:20:34 clear vision, right. I mean, if you're seeing
00:20:34 --> 00:20:36 things through static or through an
00:20:36 --> 00:20:37 interference pattern of what you're looking
00:20:37 --> 00:20:39 at, it's hard to concentrate or hard to
00:20:39 --> 00:20:41 focus. Now, it's not surprising that when you
00:20:41 --> 00:20:42 squint, you can see funny shapes and things
00:20:42 --> 00:20:44 which don't exist when you look at them,
00:20:44 --> 00:20:46 something more clearly. So to suggest that it
00:20:46 --> 00:20:48 might be the case that people who suffer from
00:20:48 --> 00:20:50 this are more likely to have pareidolia
00:20:50 --> 00:20:52 experiences, especially seeing faces and
00:20:52 --> 00:20:54 things, than those without, that's fine. It
00:20:54 --> 00:20:56 doesn't tell you a lot, apart from the fact
00:20:56 --> 00:20:58 that they can't see things very well. They
00:20:58 --> 00:21:00 put it down to this whole syndrome of visual
00:21:00 --> 00:21:03 snow as hyperexcitability in the visual
00:21:03 --> 00:21:05 cortex, which means you tend to try and find
00:21:05 --> 00:21:07 a logical explanation for what you're seeing,
00:21:07 --> 00:21:09 perhaps because they have this problem of
00:21:09 --> 00:21:11 focusing, of a distraction to how they. The
00:21:11 --> 00:21:13 visual images they have, and therefore they
00:21:13 --> 00:21:15 try desperately to find something in there
00:21:15 --> 00:21:17 and they might be more inclined to see faces.
00:21:17 --> 00:21:18 And one of the big problems with the study,
00:21:18 --> 00:21:21 the red flag pops up straight away, was they
00:21:21 --> 00:21:23 asked the people they surveyed to rate on a
00:21:23 --> 00:21:26 scale from 1 to 100, how easily they could
00:21:26 --> 00:21:28 see a face in a range of images that were
00:21:28 --> 00:21:29 being shown. So in other words, they're
00:21:29 --> 00:21:31 coming people to start with, to say, yeah,
00:21:31 --> 00:21:33 this is what we want you to say you are
00:21:33 --> 00:21:34 seeing or want you to talk about you are
00:21:34 --> 00:21:36 seeing, rather than just say, do you see
00:21:36 --> 00:21:38 anything interesting in this photo, uh, or
00:21:38 --> 00:21:40 this image? They say, do you see faces in
00:21:40 --> 00:21:42 this image? And therefore people will look
00:21:42 --> 00:21:43 for faces. It's like saying to someone, don't
00:21:43 --> 00:21:45 think of a rhinoceros. And naturally you
00:21:45 --> 00:21:47 think of a rhinoceros. You can't get it out
00:21:47 --> 00:21:49 of your head after that instantly. There's a
00:21:49 --> 00:21:51 problem with that survey, that particular
00:21:51 --> 00:21:53 survey. And it might be a thing that because
00:21:53 --> 00:21:56 people have worse vision, they tend to see
00:21:56 --> 00:21:57 shapes that aren't there more than other
00:21:57 --> 00:21:59 people do. We all do it. It's nothing
00:21:59 --> 00:22:01 particularly sort of worrisome or anything
00:22:01 --> 00:22:03 like that. But to suggest that it just might
00:22:03 --> 00:22:05 be a condition that people with bad eyesight
00:22:05 --> 00:22:07 see pareidolia see faces more often than
00:22:07 --> 00:22:09 those who don't because their focus is less
00:22:09 --> 00:22:10 clear. Maybe as you get older, you will see
00:22:10 --> 00:22:12 more faces as your eyesight deteriorates.
00:22:12 --> 00:22:15 Stuart Gary: That's the skeptics. Tim Mendham. And this is
00:22:15 --> 00:22:15 space.
00:22:31 --> 00:22:34 And that's the show for now. Space Time is
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00:23:16 --> 00:23:19 details. You've been listening to
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00:23:21 --> 00:23:23 Tim Mendham: This has been another quality podcast
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