S27E59: Venus's Vanishing Vapors: The Mystery of a Bone-Dry Planet

[00:00:00] This is SpaceTime Series 27 Episode 59, broadcast on the 15th of May 2024.

[00:00:07] Coming up on SpaceTime, why Venus is almost no water, a space railroad on the moon,

[00:00:13] and the launch of a new volcanic eruption early warning satellite.

[00:00:18] All that and more coming up on SpaceTime.

[00:00:22] Welcome to SpaceTime with Stuart Gary.

[00:00:26] A new study claims that Earth's scalding and uninhabitable sister planet Venus

[00:00:46] became incredibly dry after losing much of its atmospheric hydrogen into space

[00:00:51] through a process called dissociative recombination. The study claims that

[00:00:57] resulted in Venus losing roughly twice as much water every day compared to previous estimates.

[00:01:03] The new findings, reported in the journal Nature, are based on computer simulations,

[00:01:07] and they fill an important gap in science's understanding of the water story on Venus.

[00:01:13] One of the study's authors, Aaron Kanji from the University of Colorado Boulder,

[00:01:17] says water is vital for life as we know it. Scientists need to understand the conditions

[00:01:22] that support liquid water in the universe and that may have produced the very dry state of Venus

[00:01:28] today. Kanji says if you took all the water on Earth and spread it over the planet like jam

[00:01:33] on toast, you'd get a liquid layer roughly three kilometers thick. But she says if you did the same

[00:01:39] thing on Venus where all the water is trapped in the air, you'd wind up with only three centimeters,

[00:01:44] barely enough to get your toes wet. You see, Venus has 100,000 times less water than the Earth,

[00:01:50] even though it's the Earth's nearest planetary neighbor. And that's really confusing because

[00:01:55] both worlds are basically the same size, they have the same mass, and they were formed in the

[00:02:00] same part of the solar system out of the same material. So why the huge difference? Well,

[00:02:06] Kanji and colleagues have used computer models to try and understand Venus as a gigantic chemistry

[00:02:11] laboratory, and they zoomed in on the diverse range of reactions that occur in the planet's

[00:02:16] swirling atmosphere. They found a specific molecule, an ion, made up of one atom each of hydrogen,

[00:02:23] carbon, and oxygen, which is high in Venus's atmosphere, could be the culprit behind the

[00:02:28] planet's escaping water. Now if they're right, these findings reveal new hints about why Venus

[00:02:33] probably once looked almost identical to Earth but is now completely unrecognizable. See, if

[00:02:39] Venus is Earth's sister planet, then it's a twisted sister with a runaway greenhouse effect.

[00:02:45] Its surface is scorchingly hot, with average temperatures of 462 degrees Celsius, that's hot

[00:02:51] enough to melt lead. And those thick opaque planet-shrouding clouds? Well, they do cause rain,

[00:02:56] but the rain isn't water. Instead, it's droplets of metal-eating sulfuric acid.

[00:03:02] Scientists have seen what looks like snow caps in some of Venus's taller mountain ranges.

[00:03:07] But that snow isn't frozen water. It's actually metallic. Venus's thick cloud cover is so heavy,

[00:03:13] it crushes Venus's carbon dioxide-based atmosphere, acting like a lid on a pressure cooker,

[00:03:19] and giving the planet a surface pressure some 92 times greater than the average sea-level

[00:03:23] surface pressure on Earth. The surface of Venus is dominated by thousands of volcanic structures,

[00:03:30] more than any other planet in the solar system. Importantly, there's no evidence of any form of

[00:03:35] plate tectonic activity on Venus. Venus orbits the Sun every 224.7 Earth days. And unlike the

[00:03:42] Earth, it rotates in retrograde compared to most other planets in the solar system. That means on

[00:03:48] Venus, the Sun rises in the west and sets in the east. And the rotation is awfully slow. A day on

[00:03:55] Venus lasts 243 Earth days. That means a Venusian day lasts longer than a Venusian year. Venus wasn't

[00:04:04] always such a dry, inhospitable world. Scientists suspect that billions of years ago, during the

[00:04:09] formation of Venus, the planet received just as much water as the Earth did. But at some point,

[00:04:15] catastrophe struck. Clouds of carbon dioxide in Venus's atmosphere kicked off the most powerful

[00:04:21] greenhouse effect in the solar system, eventually raising temperatures on the surface to roasting.

[00:04:26] And in the process, all of Venus's water evaporated into steam, and most of it wound up drifting away

[00:04:32] into space. But that ancient evaporation can't explain why Venus is as dry as it is today, or how

[00:04:39] it continues to lose water into space. According to this new study, the culprit is this elusive

[00:04:45] carbon-hydrogen-oxygen ion. Water mixes with carbon dioxide to form this molecule. In previous

[00:04:52] research, the authors reported that the same molecule may be responsible for Mars losing a

[00:04:56] huge chunk of its water. Here's how it works on Venus. The molecule is being produced constantly

[00:05:02] in the atmosphere, but the individual ions don't survive for long. Electrons in the atmosphere find

[00:05:07] these ions and recombine with them, splitting the ions in two. Now in the process, the light hydrogen

[00:05:13] atom zips away and may even escape into space entirely, robbing Venus of one of the two components

[00:05:19] needed for water, H2O. The only way to explain Venus's dry state was if the planet hosted larger

[00:05:26] than expected volumes of this molecule in its atmosphere. Now there's one more twist to the

[00:05:31] findings. Scientists have never actually observed this molecule around Venus. While many spacecraft

[00:05:38] have visited Mars in recent years, far fewer have travelled to Venus. And none have carried

[00:05:43] instruments capable of detecting this hydrogen-carbon-oxygen ion. One of the surprising

[00:05:48] conclusions of this new research is that the molecule should actually be really common,

[00:05:53] one of the most abundant ions in Venus's atmosphere. So all they need to do now is go there and find it.

[00:06:01] This is Space Time. Still to come, NASA looking at building a railroad on the Moon to transport

[00:06:07] freight across the lunar surface. And a new satellite's been launched from the International

[00:06:12] Space Station to study volcanic activity from orbit. All that and more still to come on Space Time.

[00:06:35] NASA's looking at building a railway on the Moon to transport freight across the lunar surface.

[00:06:40] The Magnetically Powered Robotic Flexible Levitation on Track, or FLOTE system,

[00:06:45] would transport up to 100 tons of lunar soil or regolith and other materials a day using

[00:06:50] unpowered robots. The FLOTE would involve lightweight tracks being unfurled directly onto

[00:06:56] the lunar surface, thereby avoiding all the major on-site construction problems associated with

[00:07:01] traditional transport infrastructures like conventional roads, railways or cableways.

[00:07:07] Ethan Schaler from NASA's Jet Propulsion Laboratory in Pasadena, California,

[00:07:11] says unlike robotic vehicles with wheels, legs or tracks, FLOTE robots have no moving parts

[00:07:17] and levitate over the tracks, minimizing lunar dust, abrasion or wear.

[00:07:22] Transporting regolith across the lunar surface would be vital to NASA's plans to convert the

[00:07:26] soil into oxygen and building materials to support human bases on the Moon.

[00:07:31] Also, the extracted oxygen could be used as an oxidizer for rocket fuel.

[00:07:36] FLOTE would operate autonomously with minimal site preparation and its network of tracks

[00:07:41] could be rolled up and reconfigured to match evolving lunar base mission requirements.

[00:07:47] JPL engineers estimate it would be capable of handling payloads of more than 30 kilograms per

[00:07:51] square meter at speeds of half a meter per second. FLOTE is just one of the concepts being looked at

[00:07:57] by NASA for funding as part of the agency's innovative Advanced Concepts Programme

[00:08:02] Phase 2 projects. The others include a Fluidic Telescope or FLOOT, which would involve the

[00:08:08] creation of a large optical observatory in space not using a solid heavy piece of glass as a mirror

[00:08:14] but instead having a fluidic mirror shaped by rotating ionic fluids. The telescope would allow

[00:08:20] astronomers to search for Earth-like exoplanets, first generation stars and young galaxies.

[00:08:27] Then there's the proposal for Pulse Plasma Rockets. These would dramatically reduce transit times for

[00:08:33] humans travelling to Mars or other parts of the solar system. This innovative propulsion system

[00:08:38] would use fission-generated packets of plasma for thrust. Another idea is the Great Observatory

[00:08:44] for Long Wavelengths or GLOW. It would see a mega constellation of low frequency radio telescopes

[00:08:50] using thousands of autonomous smallsats capable of measuring the magnetic fields emitted by exoplanets

[00:08:56] and study the cosmic dark ages, a time before the first stars began to shine. Then there's the

[00:09:03] Radioisotope Thermoradiative Cell Power Generator. It would be a new in-space power source operating

[00:09:09] at higher efficiencies than current power generators. And finally there's ScienceCraft for Outer Planet

[00:09:16] Exploration. It would place quantum dot-based sensors on the surface of solar cells, enabling

[00:09:22] that cell to act like a giant innovative imager. Quantum physics would allow NASA to make scientific

[00:09:28] measurements studying how the dots absorb light. By leveraging the solar cells area, it would allow

[00:09:35] lighter more cost-effective spacecraft carrying images across the solar system. This is space time.

[00:09:42] Still to come, a new volcanic eruption early warning satellite launched from the International

[00:09:47] Space Station and later in the Science Report, artificial intelligentsia showing clear racist

[00:09:54] and woke programming. All that and more still to come on Space Time.

[00:10:14] A new satellite has been launched from the International Space Station to study volcanic

[00:10:18] activity on Earth from orbit. The Hyperspectral Thermal Imager or HITI spacecraft is a six-unit

[00:10:25] cubesat designed to measure trace gases which could be an early indication of an impending

[00:10:30] volcanic eruption. The spacecraft was initially launched from Earth on the 30th SpaceX commercial

[00:10:36] resupply mission aboard a Dragon cargo ship on a Falcon 9 rocket from the Cape Canaveral Space

[00:10:42] Force Base in Florida back on March 21. After docking to the International Space Station,

[00:10:48] HITI was deployed into low-Earth orbit on April 21. This demonstration mission will test new

[00:10:54] technologies that could provide the next generation of high spatial, spectral and temporal resolution

[00:11:00] satellites using thermal infrared imagery acquisition from low-Earth orbit. HITI Principal

[00:11:06] Investigator Robert Wright from the University of Hawaii says the mission will pave the way for

[00:11:10] future spacecraft dedicated to detecting volcanic eruptions weeks or even months in advance.

[00:11:16] Wright says hyperspectral images like HITI can measure a broad spectrum of thermal radiation

[00:11:22] signatures and they're especially useful for characterizing gases in low concentrations

[00:11:27] while defying concentrations of sulfur dioxide in the atmospheres around volcanoes. You see in

[00:11:33] the weeks and even months before they erupt, volcanoes often emit increased amounts of sulfur

[00:11:38] dioxide and other trace gases. So measuring those gases could indicate an impending eruption.

[00:11:45] HITI's sensitivity to thermal radiation will also be useful for observing water vapor and convection.

[00:11:51] Wright says a future constellation of 25 to 30 HITI satellites could monitor Earth's volcanoes

[00:11:57] for signs of impending eruptions and map soil moisture for crop management at lower costs than

[00:12:02] a single conventional satellite. I tell people that I study volcanoes from space to try and work

[00:12:07] out when they are going to start and stop erupting. The satellite is called HITI, hyperspectral thermal

[00:12:13] imaging. There are two science objectives for HITI. One is we want to try and improve how well

[00:12:18] we can predict when a volcano is going to erupt and also when a volcanic eruption is going to end

[00:12:22] and we're also going to be measuring soil moisture content as it pertains to persistence of drought.

[00:12:27] So both of those things HITI will be able to contribute to society. HITI uses a phenomenon

[00:12:32] called interference. If you've ever seen the rainbow of colors that are produced by on the

[00:12:36] side of the street when you have a film of oil over water, that's an interference phenomenon

[00:12:41] which allows broadband light to be split into its different color or wavelength or spectral

[00:12:48] components. HITI uses a Fabry-Ferrot interferometer which is about the size of my my fingernail,

[00:12:54] two pieces of germanium and we just have air in the middle. When light lands on one side it gets

[00:12:58] passed through and it gets bounced around in the cavity reflected backwards and forwards

[00:13:03] and it's very attractive as an imaging technology for a cube satellite firstly because it's small

[00:13:09] but secondly because it has no moving parts. It's just glued together solid and mounted to the

[00:13:13] focal plane of it. People are familiar with carbon dioxide dissolving from a liquid when you open a

[00:13:18] bottle of coke. Carbon dioxide is also present in magmas at depth. When you're bringing the magma up

[00:13:23] to the surface, the gases which are dissolved under pressure at depth, eventually they escape

[00:13:28] and they produce a gas cloud. Before an eruption carbon dioxide can give you weeks to months of

[00:13:34] early warning once you start detecting that elevated amount within that plume. With HITI we

[00:13:39] have the sensitivity, the spectral coverage and the spectral resolution that we can measure both

[00:13:44] volcanic carbon dioxide emissions as well as volcanic saltwater outside emissions. Our ability

[00:13:48] to measure the chemical composition of targets on the earth and how they change as a function of

[00:13:53] time in the thermal infrared has really lagged behind progress that has been made in other parts

[00:13:58] of the spectrum. Everything emits energy because it's warm. In the thermal infrared we're studying

[00:14:04] the amount of light that it emits. We make many spectral measurements with narrow wave bands which

[00:14:09] is what HITI is going to do and not only can we work out the temperature of the thing we're imaging

[00:14:13] we can also work out something about its chemical composition. So HITI is going to provide different

[00:14:17] kind of thermal infrared data than scientists have previously had available to them. One of the

[00:14:22] most frustrating things about being a scientist is that you're usually given data and you have to

[00:14:26] work with it even if it's not exactly the kind of data that you really like to bring to bear on the

[00:14:31] problem that you're trying to solve. Historically the conversion from a meaningless number to a

[00:14:37] scientifically meaningful number would take place on the ground. With HITI we're going to do this

[00:14:41] processing on board so what we have to do is convert the raw response of the camera

[00:14:46] to the thing called spectral radiance. During a given day the instrument is going to acquire about

[00:14:52] 100 gigabits of raw data. By processing it on board and then compressing it we're going to

[00:14:58] convert 100 gigabits to 4 gigabits which on download a scientist could grab, unzip and

[00:15:04] then immediately begin analyzing. A HITI's a CubeSat. CubeSats are designed to work in constellations

[00:15:10] so to replicate the functionality of a large mission using several smaller spacecraft. HITI

[00:15:15] is a technology demonstration mission so it's not designed to be a science mission it's designed to

[00:15:20] be a pathfinder for science missions. So in order to achieve high temporal resolutions of the kind

[00:15:25] that you need to study the gases emanating from a volcano before it erupts then one HITI would not do

[00:15:31] that but a constellation of eight, nine or ten HITIs would. So we work at the University of Hawaii

[00:15:36] and we're doing this but there are some things it's just better to rely on NASA to handle. The

[00:15:40] ESTO program allows for scientists to have interesting ideas and actually turn them into

[00:15:46] reality in a time scale which is not measured in decades but is measured in months to years.

[00:15:52] That's Robert Wright the director of the Hawaii Institute of Geophysics and Planetology

[00:15:57] at the University of Hawaii and this is Space Time. And time now to take another brief look at

[00:16:19] some of the other stories making use in science this week with the Science Report. A new study has

[00:16:24] shown that ultra-processed junk foods especially processed meats and seafoods are associated with a

[00:16:30] higher risk of dying prematurely. The findings are reported in the British Medical Journal based on

[00:16:36] research following the diets of 100,000 American health care workers over an average of 34 years

[00:16:42] half of whom died during the study period. The authors say there was no association between eating

[00:16:48] more ultra-processed foods and deaths related to cancer or heart problems and so the overall

[00:16:53] increased risk of death could be explained by the overall diet quality. In an accompanying editorial

[00:16:59] the authors note that it's important not to regard all foods considered ultra-processed as unhealthy

[00:17:04] in all contexts and also not to equate under-processed foods as being especially healthy.

[00:17:11] Scientists have found that harnessing the same chemical processes that capture carbon dioxide

[00:17:16] from the atmosphere could also allow for the carbon negative production of concrete.

[00:17:21] The findings reported in the Journal of the Royal Society Open Science follow experiments using

[00:17:27] olivine, a mineral commonly found in Earth's upper mantle. The mineral was broken down into

[00:17:32] an amorphous silica which has the potential to be used as a supplementary material in concrete

[00:17:37] making and nesquihonite which is able to capture and store carbon. The authors say using silica

[00:17:43] for cement would give concrete a low potentially negative carbon footprint as a carbon capturing

[00:17:48] material is being created during its production. Right now concrete's considered to be the worst

[00:17:54] construction material for greenhouse gases. Artificial intelligence or AI is the fastest

[00:18:02] growing technology in the world but there's growing concern about its ability to consider

[00:18:07] and represent diverse communities. Prominent AI applications such as Google and Meta are showing

[00:18:13] racial biases, a lack of diversity and a lack of cultural sensitivity. For example, Google's AI has

[00:18:20] been shown to be culturally woke to the point where it ignores achievements of white people

[00:18:24] such as claiming George Washington was black and the Apollo 11 astronauts were all coloured.

[00:18:29] AI expert Professor Kevin Wong from Murdoch University's School of Information Technology

[00:18:35] says in order to deal with the problem of cultural biases in AIs it's important to understand the

[00:18:40] fundamentals of different AI techniques. It's also important to remember the racist biases

[00:18:45] of the programmers scripting their AI, a clear case of garbage in garbage out.

[00:18:52] Apple has formally released its new Apple Air and Apple Pro iPads and as expected the Pro includes

[00:18:58] the new top-of-the-line M4 chip. With all the details we're joined by technology editor Alex

[00:19:03] the Harald Broyd from TechAdvice.life. Well two iPad Airs an 11 inch and a 13 inch and two iPad

[00:19:10] Pros an 11 inch and also a 13 inch now that's bigger than the 12.9 inches they had last year

[00:19:15] and the iPad Pro 11 inch is 5.3 millimetres and the 13 inch is 5.1 millimetres now that is smaller

[00:19:23] than the iPod Nano from a few years ago which was 5.4 millimetres so it's incredibly thin and already

[00:19:29] people have made jokes that well it's just going to bend this is Apple's first foldable but clearly

[00:19:32] most people are going to have this in some sort of a case and you've got to be careful because it's

[00:19:36] going to be very expensive. I remember that happened with iPhones a while ago I think it was the 6th.

[00:19:40] It was the 6th and also the 2018 iPads could bend as well but again you know if you sat on it if you

[00:19:45] if you purposefully bent it the reality is most people will have them in cases and price of these

[00:19:49] things especially if you want the two terabyte version is going to be in Australian dollars

[00:19:54] four to five grand I mean these are not cheap devices but the iPad Air is the one that's

[00:19:58] meant to be more for everyday consumer especially the one that wants the larger 13 inch screen

[00:20:03] without having to pay the pro prices. Of course the big question is did the M4 chip come out and if so

[00:20:08] with what? Yes so the iPad Air has gone from M1 to M2 and that's a big improvement for the

[00:20:14] consumer range but the pro range has skipped the M3 entirely and gone to the M4 now that's why

[00:20:20] Apple didn't launch it earlier because they were clearly waiting for this chip to be launched

[00:20:24] and it's 50% faster than the M2 I mean they didn't say how much faster it is in the M3 but

[00:20:29] even there's no M3 iPad Pro it doesn't really matter it's a faster and better device and it's

[00:20:33] got the biggest sort of most powerful neural engine which delivers AI. Now Apple has studiously avoided

[00:20:40] mentioning AI they've always talked about machine learning but this time they said it seven or

[00:20:43] eight times and they gave some examples where you could take a some sort of a dancer and just tap on

[00:20:49] this particular dancer and move it into a different video editing timeline without all the background

[00:20:53] and you can just do that with sort of with a tap and a drag. There's another example with a song

[00:20:57] with Apple's latest music software version 2 where you could just tap a button and instantly the

[00:21:02] song is broken up into the singer and the drums and the main instrument and the backing instruments

[00:21:08] and it all happens in a blink of an eye and you can then remix things. What Apple didn't show

[00:21:13] and what they were saving for their big worldwide developer conference in early June just weeks away

[00:21:18] is whether or not Apple is going to have a large language model generative AI clone or competitor

[00:21:25] to chat GPT which would be like a Siri on steroids and so there's clearly another shoe to drop in

[00:21:30] terms of what Apple's true AI response to a chat GPT is going to be and how else that will be used

[00:21:36] throughout the system. Already Samsung devices can do live translation on device whilst you're

[00:21:41] on phone call from one language to another it can automatically convert audio files as it's being

[00:21:46] recorded into text, summarize that for you, change the tone of your emails and notes from something

[00:21:52] more casual to something more professional. I mean there's a bunch of things that Samsung showcase

[00:21:56] which iPhones can do but you need different apps for that but it's built directly into the operating

[00:22:00] system and so this is something we expect to see Apple launch and the big question will be whether

[00:22:05] or not you need an M4 powered iPad Pro or forthcoming MacBook which will be launching towards

[00:22:11] the end of the year with these chips to do all that on device and also the new iPhone 16 that will come

[00:22:16] towards the end of the year or whether or not you'll be able to do a number of these things on your

[00:22:19] existing MacBook Pro devices and then how far back. Now can I use these AI features that aren't

[00:22:25] official yet on my iPhone 15 Pro Max for example, can I do it on an iPhone 15, can I do it on an iPhone

[00:22:30] 14 or 13? Now where will the cutoff be because Microsoft is going to launch its Surface device

[00:22:37] in the next week or two we'll talk about it on the show and it will have the Snapdragon Qualcomm

[00:22:42] X Elite and the X Plus and these two chips are their answer to Apple's M series chips and they've

[00:22:48] come effectively five years after the M1 was released in 2020. Now one interesting point,

[00:22:54] Qualcomm said its chip can do 45 tops that's trillion operations per second and Apple only

[00:22:59] said it can do 38 tops, trillion operations per second and this is important because Microsoft

[00:23:04] has been reported to say that to do generative AI on device you need at least 40 tops and

[00:23:09] interestingly AMD's chip does 39 and the previous one last year did 33 so Qualcomm is better at 45

[00:23:16] than Apple's at 38. And of course it doesn't end there, there's more news from Google as well. Yes

[00:23:20] as we're going to air Google will be holding its I O developer conference which will be full of AI

[00:23:24] news and information and it's also going to officially launch the Google Pixel 8a. It'll

[00:23:30] go on sale when the conference is on and that's full of AI stuff, two circle to search and Google's

[00:23:35] AI built into the phone and it's at a price in the US $499, $849 in Australia, $100 more but

[00:23:41] it's their answer to the mid-range phones that are nearly high end and have all of the pure Google

[00:23:47] goodness and seven years of OS and security updates so Google is by no means wanting to be

[00:23:51] left behind either and they have plenty of news which we'll talk about next week. That's Alex

[00:23:55] Sahara-Vroid from Tech Advice Start Life and that's the show for now. Space Time is available every

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