Active Volcano On Venus Shows It's a Living Planet (science.org) 21
sciencehabit shares a report from Science Magazine: Choked by a smog of sulfuric acid and scorched by temperatures hot enough to melt lead, the surface of Venus is sure to be lifeless. For decades, researchers also thought the planet itself was dead, capped by a thick, stagnant lid of crust and unaltered by active rifts or volcanoes. But hints of volcanism have mounted recently, and now comes the best one yet: direct evidence for an eruption. Geologically, at least, Venus is alive.
The discovery comes from NASA's Magellan spacecraft, which orbited Venus some 30 years ago and used radar to peer through the thick clouds. Images made 8 months apart show a volcano's circular mouth, or caldera, growing dramatically in a sudden collapse. On Earth, such collapses occur when magma that had supported the caldera vents or drains away, as happened during a 2018 eruption at Hawaii's Kilauea volcano. Witnessing this unrest during the short observation period suggests either Magellan was spectacularly lucky, or, like Earth, Venus has many volcanoes spouting off regularly, says Robert Herrick, a planetary scientist at the University of Alaska, Fairbanks. Herrick, who led the study, says, "We can rule out that it's a dying planet."
The discovery, published today in Science and presented at the Lunar and Planetary Science Conference, makes Venus only the third planetary body in the Solar System with active magma volcanoes, joining Earth and Io, Jupiter's fiery moon. It means future missions to Venus will be able to study "bare, gorgeous new rock" that provides a sample of the planet's interior, Gilmore says. The discovery of more volcanoes, in old or future data, will also help scientists understand how Venus is shedding its interior heat and evolving. And it will shake scientists out of their long-standing view that a spasm of activity a half-billion years ago repaved the planet's surface -- as evidenced by a relative paucity of impact craters -- and was followed by a long period of quiet.
The discovery comes from NASA's Magellan spacecraft, which orbited Venus some 30 years ago and used radar to peer through the thick clouds. Images made 8 months apart show a volcano's circular mouth, or caldera, growing dramatically in a sudden collapse. On Earth, such collapses occur when magma that had supported the caldera vents or drains away, as happened during a 2018 eruption at Hawaii's Kilauea volcano. Witnessing this unrest during the short observation period suggests either Magellan was spectacularly lucky, or, like Earth, Venus has many volcanoes spouting off regularly, says Robert Herrick, a planetary scientist at the University of Alaska, Fairbanks. Herrick, who led the study, says, "We can rule out that it's a dying planet."
The discovery, published today in Science and presented at the Lunar and Planetary Science Conference, makes Venus only the third planetary body in the Solar System with active magma volcanoes, joining Earth and Io, Jupiter's fiery moon. It means future missions to Venus will be able to study "bare, gorgeous new rock" that provides a sample of the planet's interior, Gilmore says. The discovery of more volcanoes, in old or future data, will also help scientists understand how Venus is shedding its interior heat and evolving. And it will shake scientists out of their long-standing view that a spasm of activity a half-billion years ago repaved the planet's surface -- as evidenced by a relative paucity of impact craters -- and was followed by a long period of quiet.
Big deal with a surface temperature of 900F/475C (Score:2)
for all I care, that planet could be dead as the moon.
With such surface temperatures, Musk isn't going for a trip to Venus to mine the daimonds raining down on the surface.
Re: (Score:1)
Just because like all earthly lifeforms you are limited to temperatures below 121 degC doesn't mean everyone else in the universe is. *shrug*
Don't be so self-centered!
Re:Big deal with a surface temperature of 900F/475 (Score:4, Insightful)
There have been a number of announcements about this chemical or that being evidence for life in Venus's clouds, though I don't find the evidence compelling. Our understanding of Venus's atmospheric chemistry is good in broad terms but poor in specifics (we don't even know what the "mystery UV absorber" is on Venus! Possibly iron chloride, or, perhaps more probably based on recent research, various polysulfides). We haven't studied it anywhere nearly as well as, say, Mars, and it's extremely complex (and stratified) - arguably the most complex atmospheric chemistry in the solar system after Titan's organics.
That said: Venus was Earthlike before Earth was. It used to have vast oceans (its massive water loss to space can be seen today in its extreme deuterium enrichment). And it's possible (unclear - we've studied Venus so little) that there's still patches of original crust in the highlands that were not resurfaced by Venus's planetwide resurfacing events. If so, then searching for fossils is not at all out of the question. After all, life on Earth formed within several hundred million years of Earth cooling, and we find their fossils in our ancient rocks. It's also convenient that it's Venus's highlands that are speculated to possibly be ancient, as they're more accessible (lower temperatures and pressures).
One nice thing about Venus vs. Mars, from a prospecting perspective, is that Venus is not heavily covered in sediment like Mars is. There's only two known dune fields on Venus, and various areas which might contain microdunes too small to be imaged by radar. The vast majority of Venus's surface is exposed rock. The first step, however, would be to find out whether the highlands surface truly does contain exposed pieces of ancient crust dating back to before Venus lost its seas, or not.
Re:Big deal with a surface temperature of 900F/475 (Score:5, Interesting)
Our solar system's ice giants are the ones with diamond rain, not Venus. That said, Venus surely is a very minerologically interesting planet. There's even semiconductor frosts and/or snows, possibly of more than one compound or form. Early on tellurium was considered a major candidate, but now galena is considered probable. The surface is sort of like a refinery, baking / eroding out compounds that on most rocky bodies normally stay well bound, and then precipitating them out elsewhere. It also shows signs of heavy differentiation / enrichment processes in its melts and long cooling times, both promising minerologically. There's also a lot of just plain weird stuff that we can only speculate at. For example, the longest riverbed in the solar system is there, and we don't even know what carved it (earlier speculation was sulfur, but today most speculation is on exotic low-temperature lavas).
Can the surface be accessed? Unambiguously yes. Even 1960s Soviet tech was able to handle Venus's surface. In some ways, Venus is easier to land on than Mars. It's been calculated that with the right trajectory, you could aim a large hollow titanium sphere at Venus, have it enter, descend and land all perfectly intact without any sort of heat shield, parachute or landing system. Venera 7 had its parachute fail and it still landed intact. The Venera probes lasted up to a couple hours with no cooling system at all, simply by a combination of insulation and a phase-change material that soaked up heat. Surface missions measured in days can be handled by battery-powered high-temperature heat pumps (as per work by Landis). RTGs and even solar can work on the surface, albeit with difficulty and reduced power densities (esp in the case of solar), for longer missions.
And for the difficulty, there's advantages beyond just landing. The atmosphere is so thick you can basically dredge samples, potentially even with your propulsion system. Not only is powered flight made easier, but unpowered flight is made much easier - even a small bellows balloon (accordian-like metal bellows, winched to decrease its volume and thus reduce lift) can lift a sizable payload, while tiny wings can maneuver it on ascent and descent (surface winds are very low). Returning to the hospitable middle cloud layer (the most Earthlike place in the solar system outside Earth) can be done with a phase-change balloon (lifting gas that condenses into a liquid at altitude, thus reducing lift and allowing the liquid to be collected in a pressure vessel to be released at the surface as a gas at will). And by changing altitude, the planet can be easily maneuvered across at high speeds (unlike most of the solar system). And of course at altitude, power is abundant for recharging, and normal Earth air (easily made from Venus's complex and resource-rich atmosphere) is a lifting gas.
(And no, the planet is not some sort of "acid bath" - there's no sulfuric acid at all at the surface, only SO2 - H2SO4 isn't stable there. And in the cloud decks, it's more like a sparse vog - while the individual particles are high molar, visibility is several kilometers. And huge numbers of materials are perfectly stable in H2SO4 (though it should be noted that that's not the only acid, the lower cloud layer for example appears to have a significant amount of H3PO4))
Indeed, the surface isn't even accessible to humans. The first types of suits that NASA was designing for Apollo were not soft suits, but rather hard suits - rather like the atmospheric diving suits that allow people to withstand incredible pressures. They're even more convenient for astronauts in that they don't hinder mobility as much as soft suits; they went with soft suits for the weight reduction. While an atmospheric diving suit-like spacesuit for Venus's surface would by no means be a trivial task, it's not some sort of unthinkable task, either.
It should also be pointed out that "Venus's surface" isn't just one place. There's radical temperature and pressure diff
Great post, thank you (Score:2)
Every so often on /. someone gives a response that significantly adds to my knowledge. As I don't have mod points today, this reply will have to serve instead.
Re: (Score:2)
Agreed. Every time I think about forgetting this site exists, I see a gem of a post such as the above. Slightly argumentative, but only because a valid argument supported by facts is taking place.
Would have modded up, except it was already at 5.
Let's go! (Score:2)
Re: (Score:2)
With such surface temperatures, Musk isn't going for a trip to Venus to mine the daimonds raining down on the surface.
Have you tried mentioning that to him? Maybe he ends up trying to do that out of spite. It seems to be his main motivator lately.
That and his ego.
Misleading headline (Score:3)
30 years ago they got the images? (Score:1)
They made these images 30 years ago and just now did a delta on them? Wow.
And... this is a surprise to them? Like, it's a big disscovery? Another wow. There is even more reason for Venus to be geologically active than Earth has:
- Earth sized, close to Earth, formed at the same time.
- More solar tidal effects than Earth
- More solar radiation Earth
- A completely runaway greenhouse effect
All of which mean more energy being pumped into it than Earth, and less can escape. So they roll out 30-year-old data c
fake news (Score:1)
From what I can tell, the guy found some evidence of possible current volcanic activity. It is not dispositive.
On the other hand, the most important discovery is that finally something useful actually came out of a Zoom meeting.
The greenhouse gas emitters just wouldn't listen (Score:2)
And now look where Venus is!