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View Full Version : Is a Comet on a Collision Course with Mars?



Fraser
2013-Feb-26, 06:30 PM
There is an outside chance that a newly discovered comet might be on a collision course with Mars. Astronomers are still determining the trajectory of the comet, named C/2013 A1 (Siding Spring), but at the very least, it is going to come fairly close to the Red Planet in October of 2014. “Even if it [...]

More... (http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-mars/)

Concerned
2013-Feb-26, 07:38 PM
There is an outside chance that a newly discovered comet might be on a collision course with Mars. Astronomers are still determining the trajectory of the comet, named C/2013 A1 (Siding Spring), but at the very least, it is going to come fairly close to the Red Planet in October of 2014. “Even if it [...]

More... (http://www.universetoday.com/100298/is-a-comet-on-a-collision-course-with-mars/)

Hi, I have been keeping an eye on this for the past few days. Are we talking an event that could obliterate mars?

Rhaedas
2013-Feb-27, 12:02 AM
Hi, I have been keeping an eye on this for the past few days. Are we talking an event that could obliterate mars?

While it would be quite an impact, no, it wouldn't destroy Mars. It could have interesting long term effects though. However, its current range of probability, while close to Mars astronomically, is further than the one that just went by us. So it's something to watch as more observations come in, but chances are it won't come close.

Concerned
2013-Feb-27, 12:11 AM
While it would be quite an impact, no, it wouldn't destroy Mars. It could have interesting long term effects though. However, its current range of probability, while close to Mars astronomically, is further than the one that just went by us. So it's something to watch as more observations come in, but chances are it won't come close.

Thank you.

Scriitor
2013-Feb-27, 12:39 AM
Fascinating scenario all the same. I've heard estimates that the comet nucleus might be 50km across, which is just awesomely massive. Puts the dino-killer rock to shame. If it hit it'd excavate one hell of a crater, and I guess plunge the planet into a long impact winter, but I wonder if there would be other effects.

If the comet's makeup is much like Halley's Comet (50% ice, 80% of that water ice, I believe) we're talking, what, 24 trillion tons of water if I counted it up right? Would most of that be ejected back into space or would much of it stay in the atmosphere, and in what form?

danscope
2013-Feb-27, 02:40 AM
Surely there would be some steam generated.... surely.

neilzero
2013-Feb-27, 04:06 AM
The steam cloud would cool as it expanded becoming water vapor then sleet and/or snow on the night side within a few days. I'll guess less than 1% would be lost to space the first week so possibly this comet will partly terriform Mars as that much water vapor will have a powerful green house effect, or not/ I'm guessing. I get almost 10^14 = about 52 trillion tons of water. Neil

danscope
2013-Feb-27, 06:16 AM
But it would be a mighty explosion :)

Tog
2013-Feb-27, 08:55 AM
And it'll put that little laser on Curiosity to shame.

If it does hit, how much of a priority would it be to get a probe into the new crater and how long would it take to get it there?

schlaugh
2013-Feb-27, 02:47 PM
And it'll put that little laser on Curiosity to shame.

If it does hit, how much of a priority would it be to get a probe into the new crater and how long would it take to get it there?
If Neilzero's description turns out to be correct, NASA might need to build the first floating probe.

Rhaedas
2013-Feb-27, 03:24 PM
A red Mars vs green Mars question: if we had the technology, should we try and save Mars, or should we help steer it into Mars? We don't, but if we did...

Scriitor
2013-Feb-27, 05:58 PM
The JPL Small-Body Database Browser (http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2013A1;cad=1#cad) doesn't show an update, but Leonid Elenin (http://spaceobs.org/en/2013/02/27/new-data-concerning-the-close-approach-of-comet-c2013-a1-to-mars/) now has the comet passing Mars at a nominal distance of 0.000276 a.u (37,000km from the Martian surface), significantly closer than the previous estimate of 0.0007 a.u. (100,000 or so km)

danscope
2013-Feb-27, 06:38 PM
I can just see those martians saying... " Well Chauncey, there something you don't see every day . " :)

Concerned
2013-Feb-27, 08:57 PM
The comet passing at a closer distance still would not mean a hit. The jpl data might be more interesting, when it is updated.

Concerned
2013-Feb-27, 10:24 PM
It was my understanding that it would take several months to refine the trajectory of the comet. How has it been possible to refine the orbit of the comet, 5 days after the original story was posted. Surely more data over several months is required. The previous orbital data was taken over 74 days.

Concerned
2013-Feb-27, 11:02 PM
Hi, sorry to bother all again.

I was just reading comments on msnbc news about this, and some people are saying that such a large impact could send chunks of debris headed to earth. Is this possible? Could this event affect us here on earth?

Very sorry for the email stream, but of all the nut jobs over the past couple of years, this seems like an actual real event.

publiusr
2013-Mar-03, 09:43 PM
The nucleus looks closer to 5 km now, not 50km.

Concerned
2013-Mar-04, 12:09 AM
The nucleus looks closer to 5 km now, not 50km.

Thank you for posting.