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Comet might hit Mars in 2014
- tocomment 14y agoI got to thinking. Is there any chance we could nudge this to impact the Hellas Planitia on Mars. It's the lowest point of Mars and therefore already has a higher atmospheric density (.01 ATM). So if we could double the depth and potentially add more water, it would really get us closer to a great location for a colony. http://en.wikipedia.org/wiki/Hellas_Planitia http://en.wikipedia.org/wiki/Hellas_Planitia
- tocomment 14y agoI wonder what the minimum atmospheric pressure is to grow some kind of plants out in the open? (Or bio-engineer some plants to grow). Would this get us in that ballpark? Also, what the minimum pressure a human could survive with just a breathing mask?
- Shivetya 14y agoThere is an interesting bit from NASA here that covers your concerns, http://science.nasa.gov/science-news/science-at-nasa/2004/25feb_greenhouses/ http://science.nasa.gov/science-news/science-at-nasa/2004/25...
- danielweber 14y agoI think it would be a neat high-school-level science experiment to find some plant that reproduces quickly, and then put it in a bell jar with ever-decreasing levels of air pressure to try and force natural selection to make something that can survive at very low pressures. (Edit: You won't approach Mars-level pressures with these experiments.) At the college level, I've read papers about inserting specific genes into plants to increase their hardiness with thin atmospheres.
- cryptoz 14y agoHave you read the Mars Trilogy by Kim Stanley Robinson? I bet you have, but if you haven't, you should. It's the most amazing hard science fiction regarding terraforming and colonzing Mars. Planetary-scale engineering techniques to heat Mars up, add water, increase the atmospheric pressure, etc are discussed in detail.
- xradionut 14y ago"The Sky So Big and Black" by Johne Barnes is also a interesting read about Mars-forming. (And memes, too!)
- uvdiv 14y agoNo, it's far too big.
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- jonsen 14y ago50 kilometers ... hmm ... how big must a stray celestial body bee to severely disturb the longterm stability of the solar system?
- x03 14y agoOf planeraty size and mass.
- manaskarekar 14y agoOr how fast.
- popopje 14y agoanything bigger than bumble.
- 30thElement 14y agoAssuming Mars and the comet are perfectly round and have the same density, this comet will change the speed of Mars by about 0.004 feet per year, or about a quadrillionth of it's current speed. A body large enough and fast enough to destabilize a planets orbit (in the short term) would have a pretty good chance of breaking the planet into pieces.
- tocomment 14y agoCan anyone calculate how much this impact might heat up Mars? (I've heard even a little heating might set off a chain reaction and substantially increase the temperature?)
- jerf 14y agoOver the long term, zero. The instantaneous hit is dominated by the still much larger amount of energy continuously entering Mars from the sun and leaving due to thermodynamics. When we talk about impacts changing climate on Earth, it has nothing to do with the instantaneous heat increase itself. It has to do with how the impact can change the rate at which Earth receives and retains heat, by changing the atmosphere. And Mars hasn't got very much atmosphere to change, so even that isn't much of a factor.
- tocomment 14y agoBut I'm thinking if it hits a pole it could release CO2 and permanently affect the temperature.
- jerf 14y agoIt's still unlikely. The universe tends to be stable, because if an impact could heat up Mars, it would have, over cosmological time. This is not Mars' first impact. Our Earth intuitions are really wrong for dealing with the rest of the universe. The rest of the (known) universe doesn't have intelligent critters on it making active and wild changes in very short periods of cosmological time. The universe is generally full of stable systems, in the physics sense of the term "stable". To the extent that you think otherwise, it's because we humans are interested in the unstable bits and they get a lot of play in the press, but we know and talk about them because they are the exceptions.
- scarmig 14y agoTransients on this scale, however, could last hundreds of years. Even on Mars, CO2 takes a while to escape from the atmosphere; on human time scales we'd see a new metastable Martian temperature. (Assuming a bunch of CO2 actually were dumped into the atmosphere, that is.)
- kingkawn 14y agoSetting off a volcanic eruption, instantly oxygenating mars, saving Arnold Schwarzenegger
- davidjohnstone 14y ago50km is massive. Earth's largest crater[1] is 300km across, and that's thought to have been created by an asteroid 5-10km in diameter. The 180km Chicxulub crater[2] (this impact is generally believed to be largely responsible for the extinction of dinosaurs) was around 10km in diameter. I'm kind of hoping this turns out to be something. I thought the Russian meteor the other week was a most amazing natural event, and something far bigger than that would be incredible (not to mention safe for humanity in this case). EDIT: 50km is actually the upper estimated limit of the size of this comet. Wikipedia[3] says 8-50km. It's still huge. 1: http://en.wikipedia.org/wiki/Vredefort_crater http://en.wikipedia.org/wiki/Vredefort_crater 2: http://en.wikipedia.org/wiki/Chicxulub_Crater http://en.wikipedia.org/wiki/Chicxulub_Crater 3: http://en.wikipedia.org/wiki/C/2013_A1 http://en.wikipedia.org/wiki/C/2013_A1
- tomjen3 14y agoMassive doesn't even come close. http://www.truthistreason.net/ground-zero-ii-interactive-nuclear-blast-calculator-and-fallout-map http://www.truthistreason.net/ground-zero-ii-interactive-nuc... allows you to nuke a given area and see the effects. Its biggest "bomb" is the Chicxulub crater - and compared to that, even the Tsabomba are a joke.
- gnarbarian 14y agoComets also are travelling waaaay faster than asteroids because they come from farther out in the solar system which gives them more potential/kinetic energy. Generally speaking a comet will be going about three times as fast and carry about nine times the kinetic energy as an asteroid of the same size.
- pixl97 14y agoI would think that an impact of mars by this body would delay any further plans of visiting mars for a while. The level of atmospheric dust would be... tremendous. I wonder if 'backsplash' of rocks and other material would pose a threat to the mars orbiters?
- jerf 14y agoMars' atmosphere is very thin compared to ours. I seriously doubt we could get there before the effect has cleared from the atmosphere. Even if we left right now.
- mtgx 14y agoWouldn't this be helping us terraform Mars faster? I think a lot of CO2 is trapped in ice on Mars, and we'd need that to make (presumably genetically enhanced) plants live there. A body that large hitting Mars could help raise its temperature.
- Zuph 14y agoIt would also dig a deep crater. Depending on the depth of the hole, the atmosphere may be dense enough at the bottom that you wouldn't need anything more than an oxygen mask and a heavy coat to walk around outside. Some have proposed intentionally diverting comets into Mars to Terraform it, as they would add water and create craters which could be used as oases.
- vitno 14y agoThe atmosphere isn't dense enough for a crater to sustain that type of atmospheric density... yet...
- Zuph 14y agoIt depends on the depth of a crater. A 15-20 mile deep crater would get you to Mt. Everest levels of density. Of course, that kind of a crater would require a direct impact from an object of this size, not a glancing impact.
- Jabbles 14y agoIt would probably throw up enough dust into orbit to prevent anything landing for the next 1000 years :(
- manaskarekar 14y agoIs there any info on how this would affect the rovers?
- ars 14y agoDepends where it hit, but it stands a good chance of destroying the rovers.
- blaze33 14y agoThere is a more recent post from Leonid Elenin with updated data: http://spaceobs.org/en/tag/c2013-a1-siding-spring/ http://spaceobs.org/en/tag/c2013-a1-siding-spring/ "the comet might pass just 41,000 km [...] from the planet’s centre [...] 100% certainty that the planet will pass through the gaseous envelope of the comet [...] will be subject to intensive bombardments by microparticles which, among other things, might cause malfunction of the space probes currently there."
- meaty 14y agoHm. Interesting to observe, but will this throw a lot more crap into space that we then have to worry about in a few decades? I assume it'll knacker any landers we have there as well through either seismic activity or dust penetration.
- jerf 14y agoNot much, if any. Even what we'd consider a very large impact still almost instantaneously accelerates the target matter, so it has a velocity that is radial away from the impact point. That's not an orbit velocity. Mass will either fall back to Mars or escape entirely, but little to none of it will enter any sort of permanent orbit. Same reason why you can't just shoot something into orbit from Earth's surface with one instantaneous acceleration, and that getting into orbit is not merely a matter of standing on a very tall tower. Truly enormous impacts can change the rules if thing hitting Mars is large enough to shift the center of mass of the whole system. The Moon is thought to have been formed from something the size of Mars or so hitting Earth a very long time ago. But even in our rather violent universe, that's the exception, not the rule, obviously.
- meaty 14y agoThanks for the detailed response :)
- alexandros 14y agoWitnessing such an event could help get humanity serious about existential risk, from comets or otherwise. I, for one, am hoping for an impact.
- Fargren 14y agoCan't we help this happen somehow?
- youngerdryas 14y agoNot by 2014.
- cryptoz 14y agoAlmost certainly not by 2014, but there are still a lot of factors that are unknown. We certainly can't launch anything to go out there since the travel time alone forbids it. But if more accurate estimates come in a few months from now putting it very close, but missing, Mars, there might be some kind of crazy laser engineering to be done. I realize how crazy this is, but there's always reason to dream and brainstorm.
- mtgx 14y agoIn a way this is why I'm a bit disappointed that meteor didn't pass across US. Since it passed across another country, I don't think they now see it as much of a "threat" as they would've if it passed across US' sky. On the other hand, I'm glad at least it passed one of the big countries like Russia, which now want to form an international anti-asteroid defense system. If this would've passed across Iceland, nobody would've cared.
- kamaal 14y ago>>could help get humanity serious about existential risk A comet hit Jupiter in the 90's (http://en.wikipedia.org/wiki/Comet_Shoemaker%E2%80%93Levy_9 http://en.wikipedia.org/wiki/Comet_Shoemaker%E2%80%93Levy_9) we watched it and did nothing about it. Yes I understand that we may get serious about our own house when the neighbors house is on fire. But frankly I don't think we will ever get serious. Right now Mankind's main priorities are in inventing weapons and finding most ingenious ways to kill each other.
- Achshar 14y agoIf it does infact hit, will there be enough time b/w impact and shock wave for curiosity to upload a high def video of the asteroid entreating the atmosphere to a satellite if it is in it's vicinity?
- maaku 14y agoNo. These things are pretty much store-and-forward. IF the timing is just right, Curiosity could transmit direct line-of-sight to Earth, but we're talking very low data rates.
- erre 14y agoThe obvious question: will Curiosity see it? If so, it should be able to get some AMAZING footage!
- sageikosa 14y agoCuriosity's dash cam? Better be playing house music.
- pointernil 14y agoYes, if Curiosity can withstand the shockwave and other results of the impact, that is.
- ceejayoz 14y agoIf Curiosity sees it, Curiosity's shortly to be in a whole world of hurt.
- n3rdy 14y agopoor robot :(
- uvdiv 14y agoThis is hyperbole. (no pun) "Comet C/2013 A1 may fly past at a very safe distance of 0.008 AU (650,000 miles)," O'Neill wrote, "but to the other extreme, its orbital pass could put Mars directly in its path.
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- btilly 14y agoWow. What are the odds? Just doing quick ratios and squaring them, if the comet follows the initial projections, there are only about 230 large objects coming this close for every one that actually lands on Mars. (And Earth gets hit with about 3.5 of these for every one that hits Mars. Our last is estimated to be 65,957,000 +- 11,000 years ago.) This is literally a once in a million years near miss! Of course the odds now are much higher than they normally would be. The fact that it is on a hyperbolic orbit means that it comes from outside of the Solar System. The density of such objects is much higher near the galactic plane than elsewhere. However the Sun bobs up and down, spending most of its time away from the galactic plane and crossing it every 30 million years or so. We last crossed it something like 100,000 years ago and are now heading away, so are still in a period where interstellar objects are more likely to come barreling through. So the odds are higher than they normally are, but even if you generously account for the currently increased risk, this is still a once in a civilization near miss. Of course the initial estimate may be wrong. From the article the uncertainty is much bigger than the distance to Mars. If the uncertainty is the stated 650,000 miles, then we've got roughly a 1/24,000 chance of a direct impact. (I am sure that more informed people will come up with much better estimates in the not too distant future.)
- jessriedel 14y ago>Just doing quick ratios and squaring them, if the comet follows the initial projections, there are only about 230 large objects coming this close for every one that actually lands on Mars. How did you come to this estimate? The Martian radius is 3,400 km while the current projected closest approach is 109,000 km. I think the uncertainty the maximizes the chance of impact is just the difference of those two, so my best guess for a chance of impact is (3.4/109)^2 = 0.1% (one in a thousand). And any other quoted uncertainty by the scientists should only decrease this probability. EDIT: Ahh, I see, you must have used diameter. I think radius is more appropriate here, but I don't think either of us are accurate enough for a factor of 4 to matter much.
- btilly 14y agoWhoops, I did use diameter. You're right, I should have used radius.
- mtgx 14y agoWatch this recent episode of Colbert, and his interview with Michio Kaku, where they talk about the recent asteroids, and also about the much larger one "grazing" Earth's atmosphere in 2029, and that "may" hit Earth in 2036 (depending on how much it grazes Earth's atmosphere in 2029). It starts at 15:30 or so: http://www.colbertnation.com/full-episodes/tue-february-26-2013-dr--michio-kaku http://www.colbertnation.com/full-episodes/tue-february-26-2...
- ed209 14y agoIf it's about the asteroid Apophis, then the last I heard was that it won't be hitting earth (I can't see the video on that link for some reason, but the dates rang a bell). http://www.skyandtelescope.com/news/home/Asteroid-Apophis-Takes-a-Pass-in-2036-186245171.html http://www.skyandtelescope.com/news/home/Asteroid-Apophis-Ta...
- bennyg 14y agoFortunately, it won't hit us in 2036 either. "Preliminary observations by Goldstone radar in January 2013 have effectively ruled out the possibility of an Earth impact by Apophis in 2036." http://en.wikipedia.org/wiki/99942_Apophis http://en.wikipedia.org/wiki/99942_Apophis
- vinkelhake 14y agoOn the bright side, it could take care of the 32-bit time_t problem.
- danielweber 14y agoBut not soon enough for the 32-bit unsigned NTP wraparound. (It's funny how 32 bits is about 70 years more than 31 bits, and the "31-bit epoch" started 70 years after the "32-bit epoch.")
- Thrymr 14y agoA direct hit doesn't seem to be all that probable, but Mars is still likely to pass within the comet's coma and be pelted by debris [1]. [1] http://www.slate.com/blogs/bad_astronomy/2013/02/28/mars_impact_the_red_planet_may_get_hit_by_a_comet_in_october_2014.html http://www.slate.com/blogs/bad_astronomy/2013/02/28/mars_imp...
- SODaniel 14y agoRead the title as 'Comet might hit in March 2014' followed by '50 km' and almost choked to death on my morning Espresso.