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Venus May Have Active Volcanoes
An anonymous reader writes: The European Space Agency's Venus Express spacecraft has discovered hot lava flows on the surface of Venus, providing the best evidence yet that the planet may have active volcanoes. "[U]sing a near-infrared channel of the spacecraft's Venus Monitoring Camera (VMC) to map thermal emission from the surface through a transparent spectral window in the planet's atmosphere, an international team of planetary scientists has spotted localized changes in surface brightness between images taken only a few days apart (abstract)." Venus is fairly similar to Earth in size and composition, which suggests it has an internal heat source. One of the biggest mysteries about Venus is how that heat escapes, and volcanic activity could be the answer.
Can anyone explain why a volcanicly active planet doesn't have a magnetic field? Isn't the liquid core what generates the field?
Probably because it has a very slow rotation.
"First they came for the slanderers and i said nothing."
Plate tectonics might not be present on Venus because of "self repair."
"First they came for the slanderers and i said nothing."
They mentioned that the flow temperatures recorded in the hot pixels are colder than typical basaltic / rhyolitic flows and were speculating that they didn't catch freshly erupting material, but rather material that had a little time to cool. But I can't help but wonder.... does Venus have carbonatite flows? They're colder, and if there's anything Venus isn't short on, it's carbonic compounds...
(BTW, with those not familiar with carbonatite lava, its really weird stuff - incredibly fast-flowing and smooth (often less viscous than water), erupts looking black or dark gray like oil, doesn't (visibly) glow during the day (just a fast moving black substance), at night it has a weird maroon glow, and it oxidizes to bright white as it ages)
(Just one of many unusual types of volcano :) )
What about the Ant People? They owe us money.
It looks like Venus might have a frozen core as far as we know, at least from a few minutes of Googling and finding a couple hits mentioning that. -> http://cseligman.com/text/plan...
Wikipedia has a really good article about the geology of Venus. Worth a read.
"First they came for the slanderers and i said nothing."
The oddball rotation is the same as everyone else, just so slow that when you account for it revolving around the sun, it's sunrise and sunset are the opposite of everyone else's.
The lack of magnetic field is what makes the atmosphere dense. O2 is lighter than the other compounds in the atmosphere, so it floats to the top, where the solar wind strips the upper layers of the atmosphere. So if we were able to terraform the planet, changing the atmosphere to breathable, it wouldn't be a stable transformation, and the atmosphere would return to something like it has now. All from the lack of a magentic field.
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Maybe I'm out of date here, but I thought there was general agreement that moonless planets would just quietly cool from the outside in. No plate tectonics or vulcanism, because there are no tides to stir things up.
Since TFA writes "These observations are close to the limits of the spacecraft’s capabilities and it was extremely difficult to make these detections", maybe this should be taken with a large grain of salt?
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