The Earth would eventually become tidally locked to the Sun, given a long enough time, but it won’t be given a long enough time. Venus is close to a lock, but Earth is too far out.
Mercury, meanwhile, won’t slow down any more from its current motion, even though it doesn’t always face the same side towards the Sun. It’s got what’s called a harmonic lock, where its day is exactly two-thirds the length of its year. This is actually more stable than anything slightly faster or slower, so until its orbit decays, its rotation won’t decay. This doesn’t usually happen, because you need a rather high orbital eccentricity for it to work: Mercury’s eccentricity is the second-highest of any planet in the System.
Lemur866: Yes, I know…maybe I was a bit rash to say “a couple of minutes” but I can’t see us lasting months either.
Even if we only allowed the temp to drop by 1 degree per hour (the temperature does drop more quickly than that at night, I think) then it would only take a few days to become very uncomfortable…
Would you accept a figure like that, if you assumed there would be no more cloud cover? That would mean that in about 8 days the nitrogen in the air would start to condense. As for the oceans, yes lotsa water, but big freezer
I still don’t buy the weeks/months thing…sure the core would still be molten, but that wouldn’t help us up here on the surface (I suppose we could all live underground or something…)
Off topic: rather than the sun actually going out, I suppose we could imagine aliens taking over the planet, but “cleaning” it first, by putting a large (!) reflector in between earth and the sun, in order to block any solar radiation from reaching earth.
Dylan…sure, I don’t know if it would take days or weeks to freeze everything. But it would be in that range, rather than hours or minutes.
Also, remember that the temperature curve isn’t going to be a linear function like 1 degree/hour. The colder it gets, the slower earth will radiate heat into the 3K background, and the more heat the surface will get from the interior. Admittedly this isn’t going to help the humans much. I don’t think we’d notice much slowdown on the curve until the atmosphere started snowing out…
Yes, the Earth would eventually become tidally locked with the sun. To bad the Earth won’t be around by then, since the sun will have ballooned up to red giant status and the earth will essentially be inside the sun. Our orbit will decay before the tidal lock can develop. Someone could calculate how many billions of years it would take for tidal friction from the sun to lock the earth, then calculate how long it would take for the sun to go red giant. Yep, someone could.
So, what would happen if it stopped ALL OF A SUDDEN? (Without all the trekkian technology) Would we all be thrown violently to the left a few miles? Out into space? Would my bowl of Frosted Rice Krispies™ spill onto the carpet? I assume there would be lawsuits…
Geothermal/Geologic activity would continue pretty much as usual for at least a few billion years since the earths interior generates much of its heat via the decay of radioactive isotopes.
The bugs living down by the thermal vents might have a tougher time of it as the ice closes in and all the acids,metals etc. released by the vents accumulates in the small pockets of ocean that remain liquid.
