51–60 of 74 posts
Commented this and got flagged: “We need boots on the ground to back the good science behind these findings.” Why is wanting to send people to mars to confirm or leverage these findings so offensive?
I was under the impression that abundant evidence of water on Mars had already been found, though I suppose this adds to the pile. There's this from 2008: https://www.space.com/5546-proof-water-ice-mars.html It seems to show evidence for subsurface ice on Mars now, though I'm not sure if this is H2O ice or CO2 ice.
Commented this and got flagged: “We need boots on the ground to back the good science behind these findings.” Why is wanting to send people to mars to confirm or leverage these findings so offensive?
Mars lost all of its (surface) water presumably due to solar wind, and thus never had time to evolve complex life. Earth would have faced the same fate were it not for the fact that the Moon collided with us at some distant point in time, surrendering its iron core to ours. Now, our Rare Earth has an unnaturally large active iron core, resulting in an unnaturally efficient magnetic field which is able to protect our…
Just wondering, what would have stopped the Earth from having enough iron on its own in the first place? If the Moon could have that much iron, the Earth could as well have had it without needing to mix with the Moon, they're made from the same original matter after all.
Earlier quoted context omitted.
Mars is smaller and cooled down before Earth. That means it had liquid water while the Earth was still too hot. Therefore, it's possible that life first appeared on Mars, and was later transferred to Earth on a meteorite.
Interesting. How would a meteorite pick something up in one planet to carry it to another planet? I'm presuming that the hypothetical meteorite does not originate in Mars.
It's kind of a mind boggingly huge billiard game.
With a bit of luck, life was somewhere around the initial impact, a couple bits of life survive blast energy, cold of space, radiation exposure, passage of time, atmosphere entry, and impact, and finally feel cozy enough on the new rock to replicate.
Now, the metagame is to assign numbers to all of that, and compare that to the odds of molecules assembling themselves into spawning life locally by itself. Also the latter must have happened somewhere first anyway, the question mostly being which of it is it for Earth.
This seems incredibly far fetched but the time scales are galactic, and so it kind of looks like it happened a few times over but we're not quite sure yet:
Mars lost all of its (surface) water presumably due to solar wind, and thus never had time to evolve complex life. Earth would have faced the same fate were it not for the fact that the Moon collided with us at some distant point in time, surrendering its iron core to ours. Now, our Rare Earth has an unnaturally large active iron core, resulting in an unnaturally efficient magnetic field which is able to protect our…
It's not that the water "blew away" in the solar wind, it's that the atmosphere did, taking the water vapor in the atmosphere with it. This is a very gradual process, which would happen on Earth too, if not for the magnetic field. I don't know that the collision with the moon is the secret here or not. I think it's complex.
I don’t know enough to know if that supports the GP’s conclusion or not, but it may.
Earlier quoted context omitted.
Just wondering, what would have stopped the Earth from having enough iron on its own in the first place? If the Moon could have that much iron, the Earth could as well have had it without needing to mix with the Moon, they're made from the same original matter after all.
The OP mispoke. It wasn't the moon that collided with earth, but another planet around mar's size. As a result of the collision the the core of that planet combined with the earth and the crust and parts of the mantle were ejected and coalesced into the moon. https://en.wikipedia.org/wiki/Giant-impact_hypothesis
I was under the impression that abundant evidence of water on Mars had already been found, though I suppose this adds to the pile. There's this from 2008: https://www.space.com/5546-proof-water-ice-mars.html It seems to show evidence for subsurface ice on Mars now, though I'm not sure if this is H2O ice or CO2 ice.
Earlier quoted context omitted.
The OP mispoke. It wasn't the moon that collided with earth, but another planet around mar's size. As a result of the collision the the core of that planet combined with the earth and the crust and parts of the mantle were ejected and coalesced into the moon. https://en.wikipedia.org/wiki/Giant-impact_hypothesis
I think the point still stands though, right? The moon is only 1% the mass of the Earth so if we had all that extra crust it wouldn't make our crust to core ratio so off that we couldn't have an atmosphere.
Without the event we'd have a planet even smaller than mars!