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Comet To Make Close Call With Mars
sciencehabit writes In mid-October, a comet sweeping through our inner solar system for the first time will pass near Mars—so close, in fact, that if it were buzzing Earth at the same distance it would fly by well inside our moon's orbit. While material spewing from the icy visitor probably won't trigger the colossal meteor showers on the Red Planet that some scientists predicted, dust and water vapor may still slam into Mars, briefly heating up its atmosphere and threatening orbiting spacecraft. However it affects the planet, the comet should give scientists their closest view yet of a near-pristine visitor from the outer edges of our solar system.
I don't understand the concept of first pass. Do they really mean "first pass ever" which I suppose would also mean humanity will never ever interact with this comet ever?
Or is it "first pass since we are able to see them, but it's part of the Solar System and it will eventually come back.
If this happened (optimistically) 50 years from now, we'd be able to deflect the comet to HIT mars, thus delivering a lot of water and warming things up a bit. (Only, I'm afraid, a little bit of terraforming, it would probably take thousands of such comet strikes to make the planet "habitable"). Or we could make it hit one of the moons and, if done very carefully, could deliver said water to possible Mars Moon colonists (but they'd have to find a way to keep the resulting fragments from ruining near-Mars space for space travels).
More realistically, I wonder if NASA (and the ESA) have plans to move their spacecraft for best viewing. If they're worried about damage, they could have them be on the other side of the planet when it makes its closest approach. If there are any spacecraft that are on their "last legs" (low propellent, malfunctioning equipment, no more spare reaction wheels), perhaps they could even make a very risky close approach!
I expect there will be some great images! (If the HiRes camera on the Mars Reconnaissance Orbiter can take 1m resolutions of Mars from orbit, it surely will be able to take great pictures of a comet only a few tens of thousands of kilometers away).
The moon is about 384,000km away from the earth. The earth is about 6,400 km wide. That means only 0.027% of the area inside the moon's orbit is occupied by the earth. So this "near miss" was better described as a 1 in 3600 to one odds of hitting mars.
I was when I first found out that Falco is In Concert now, and hippies are not invited.
Has anyone calculated what effect Mars's gravity will have on the comets trajectory? Will it gain/lose velocity relative to the sun? Will it's orbit be narrower/wider (will the close encounter send the rock tumbling out of the system again, or will it smash into the sun)? Or will the forces involved be simply too small to have the tiniest effect?
-- I am the Monkey Guru.
While the solar wind will blow away the atmosphere in a (perhaps) short time geologically speaking, in a human timescale it would likely take thousands of years. By then, the humans could have implemented a giant electromagnetic shield (powered by sharks with frickin lasers) or have developed wormholes to directly transfer water from the water from Jupiter's moons or have migrated to the far reaches of the galaxy. Or have gone extinct.
Mars didn't become the dry desert it is today in an instant, I believe for the first half billion years or so it was a warm wet place (because of the cometary impacts during the chaotic early solar system. Hence all the evidence of flowing water). Plenty of time.
By the way, responding to other posts, it is very easy to move satellites great distances in orbit GIVEN TIME. A simple 1m/sec change in velocity would, after a month, result in change in distance of several thousand kilometers. Remember that these spacecraft are capable of quite substantial delta-vee changes (in the KILOmeters/sec). And that isn't even taking into account any kind of sophisticated planning by the mission controllers (like using gravity assists or chaotic gravitational effects "the interplanetary highway").
I'm surprised how many got this reference