Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Petrochemicals on 07/09/2021 01:10:34
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Did the fluid from the moon escape to earth? We know the earth has been geologically active and has polar water so what happens to the gasses that accumulated on the moon?
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Did the fluid from the moon escape to earth? We know the earth has been geologically active and has polar water so what happens to the gasses that accumulated on the moon?
This seems to be a half hearted WAG at best.
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The majority of the Moon's atmosphere was probably lost to space. Due to the Earth's stronger gravity, some of it could have potentially made its way there. However, I'd like to point out just how far away the Earth is from the Moon: https://en.wikipedia.org/wiki/Orbit_of_the_Moon#/media/File:Moon_distance_range_to_scale.svg
I would thus expect only a very tiny amount of the Moon's lost atmosphere to have found its way to Earth.
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Did the fluid from the moon escape to earth?
There is a theory that the Earth-Moon system resulted from the collision of the early Earth with a Mar-sized planetoid nicknamed Theia (at a time when the solar system was a lot more chaotic than it is now).
See: https://en.wikipedia.org/wiki/Giant-impact_hypothesis
If Theia carried a lot of water, then that would have been added to the Earth-Moon system.
But the impact would have blasted volatiles into space, melted the rocky surface of the Earth, and the molten debris in orbit would have clumped together to form the Moon.
Fortunately, the Earth has enough gravity to retain an atmosphere, while the Moon's atmosphere is a very good vacuum, and very transient.
It is currently thought that asteroids (perhaps including Theia) were the source of most of Earth's water.
See: https://en.wikipedia.org/wiki/Origin_of_water_on_Earth#Asteroids
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The majority of the Moon's atmosphere was probably lost to space. Due to the Earth's stronger gravity, some of it could have potentially made its way there. However, I'd like to point out just how far away the Earth is from the Moon: https://en.wikipedia.org/wiki/Orbit_of_the_Moon#/media/File:Moon_distance_range_to_scale.svg
I would thus expect only a very tiny amount of the Moon's lost atmosphere to have found its way to Earth.
But how close was the moon, how eccentric its orbit?
Fortunately, the Earth has enough gravity to retain an atmosphere, while the Moon's atmosphere is a very good vacuum, and very transient.
Mars lost much of its atmosphere too yet has significant gravity, I thought it was to do with the molten magnetic core.
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But how close was the moon, how eccentric its orbit?
Ah yes, I'm glad you brought this up. I had completely forgotten that the Moon was significantly closer when it first formed (33,000 - 44,000 km). That would have made atmospheric capture more plausible, but I still think the majority would have been swept away by the solar wind.
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It reminds me of that 'dooms day book' . A quite old science fiction from my youth in where the earth is split into two, by the moon as I remember it? It's a far fetching but rather nice book, or thriller, accepting its premises.. I'll see if I can find what it was called
Nope, couldn't at a glance.
https://en.wikipedia.org/wiki/List_of_apocalyptic_and_post-apocalyptic_fiction
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But how close was the moon, how eccentric its orbit?
Ah yes, I'm glad you brought this up. I had completely forgotten that the Moon was significantly closer when it first formed (33,000 - 44,000 km). That would have made atmospheric capture more plausible, but I still think the majority would have been swept away by the solar wind.
Close distances, eccentric orbits, gravitational attraction and the solar wind could combine to transfer atmosphere.
If comets are balls of mainly ice there is easily a good source for Earth's water in the moon.
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If comets are balls of mainly ice there is easily a good source for Earth's water in the moon.
Please clarify the connection?
- The Moon is not a comet, and (according to current theories) never was a comet, so how is it a good source of water?
- If you are talking about comets crashing into the Moon: The Earth's gravity is about 80x stronger than the Moon, and the Earth is a bigger target. So far more comets would have crashed directly into the Earth than crashed into the Moon, and then had some splashover to Earth.
what happens to the gasses that accumulated on the moon?
If a comet crashed into the Moon, volatiles would be immediately vaporized, and spread out into space
- Most volatiles would be carried off the the Solar wind, never to return
- Some would end up hitting Earth (just like some Moon rocks have been discovered on Earth, blasted off the Moon by meteorite impacts on the Moon)
- Some would land back on the Moon. If it arrived in places exposed to the searing midday Sun (130C), they would be boiled off the Moon. However, if they landed at some point that was near absolute zero, they would stick there as ice.
Some of the permanently-shaded craters near the Moon's South and North poles are believed to have stores of frozen water, which are being investigated as a source of rocket fuel and drinking water (much cheaper than lifting water off the Earth).
- But uncomfortably cold to be an ice miner!
- More recently, some researchers have suggested that some water may persist in permanently-shaded locations under rocks
- And there is water contained within rock crystals, but you have to melt the rocks to extract the water (sounds like hard work!)...
See: https://en.wikipedia.org/wiki/Lunar_water
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If comets are balls of mainly ice there is easily a good source for Earth's water in the moon.
Please clarify the connection?
- The Moon is not a comet, and (according to current theories) never was a comet, so how is it a good source of water?
Or an asteroid. The same source material is what I am thinking. Of course with Jupiter's migration it is hard to say what went on.
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If comets are balls of mainly ice there is easily a good source for Earth's water in the moon.
There may be more water on the moon than we know and we must remember that the moon gets very hot for about 12 days hot enough to boil that is why the astronauts landed on the moon during its early mornings before the sun heated up the surface. Having said that most of the water that was on the moon in the past may have boiled off and due to the low gravity and lack of atmosphere the vapour would have left the moon. There are deep craters at the moon's poles that never receive sunlight and that is where the remanding water most probably still is.