Comet will make a close pass, or impact mars in the September of 2014 !UPDATED!

[Ignuus66]

Comet Comet C/2013 A1 (Siding Spring) is a massive comet with a 15-50 km diameter on a clockwise (highly) elliptical orbit around the Sun, and will make a close pass next to mars, however, it is possible that the comet will actually impact mars with a speed of 57km/s, and would have an impact force of around 1-20 billion megatons of tnt (compare that to the tsar bomb, which had a force of 53 megatons). This collision would even be visible from earth, and the impact crater left by such a collision would be 2 km deep and 150-500 km wide.

If it would not impact we would be able to take very high-resolution images with the mars orbiter, and if it impacts, we will get very interesting data about the impacts of objects like these, and would help us defend against possible objects that may threaten Earth.

Orbit of Siding Spring

https://www.youtube.com/watch?feature=player_embedded&v=eoXfKeJurl4#! Visualization of the comet making a close pass.
(using program called space engine, might make a post about it in the future)

Tld;DR; A comet will pass very close to mars or impact it. Que awesome pics. Space fans like me excited.

EDIT: The collision chance has been reduced to 1/120,000 and will probably pass by at a distance of ~110000 KM-s

[Qilby]

This will be the greatest thing to happen to Mars since M&Ms.

[Tuyu]

Too bad there's really no chance of the comet being captured by Mars. It's similar in size to Phobos and Deimos.

OTOH, if it does impact, wouldn't that be the kind of event that resulted in Martian rocks being found on Earth?

[Ignuus66]

Too bad there's really no chance of the comet being captured by Mars. It's similar in size to Phobos and Deimos.

OTOH, if it does impact, wouldn't that be the kind of event that resulted in Martian rocks being found on Earth?

If the comet is 50 kilometer wide, then yes, it is very much a possibility, but it would take millions of years for fragments to collide with earth, but it is a possiblity.

[techmaster-glitch]

  Wasn't...the K-T Extinction asteroid 15 kilometers or -less-? (something like 6-9 miles across?) If that's correct, and this coment is bigger than that, and if it actually hits mars, we'll be seeing a bigger impact than the one that killed the dinos 

[Ignuus66]

Wasn't...the K-T Extinction asteroid 15 kilometers or -less-? (something like 6-9 miles across?) If that's correct, and this coment is bigger than that, and if it actually hits mars, we'll be seeing a bigger impact than the one that killed the dinos 

Remember that the one that killed the dinos was probably denser than Siding spring, but impacted at a "measly" 30 km/s compared to the 56 km/s that siding spring might impact at.
(far worst case scenario below)

Assuming a 50 km diameter comet impacting mars, It would, quoting a russian astronomer: (forgot his name, he created the space engine program, and is known as space engineer in the forums) http://en.spaceengine.org/forum/

"If this comet really so big (50 km), the impact will be catastrophic. Collision of such a mass (3.2*1016 kg, if density is 0.5 g/cm3) with a Mars at huge velocity of 56 km/s will release 5*1025 Joules of energy (= 12 millions gigatons TNT). Impact will create a crater 500 km in diameter, blow out atmosphere and cracking surface of the entire planet. Rovers will be destroyed by powerful seismic shakes of 12-13 magnitude. Explosion's fireball will be seen from Earth during many hours, with brightness compared to the full Moon. Fireball of melted rocks will flow around entire planet, heating the surface to hundreds of degrees (like a giant pyroclastic flow). Huge debris up to 1 km in diameter will be thrown into space, together with millions Chelyabinsk-like meteoroids - even Martian orbital satellites will be destroyed. Entire surface of the planet will be bombarded by debris at almost 1st cosmic velocity (3.5 km/s), and covered with few cm dust layer, increasing to few kilometers near the crater.

--- Let's hope this very pessimistic assumption will not actually happen.

[Qilby]

Such a beautiful scene, for a pessimistic assumption. It would be great for our space programs, if only to serve as a reminder of what could happen to us if we did not properly prepare for something ahead of time.

I yearn for such catastrophe.

[Ignuus66]

Such a beautiful scene, for a pessimistic assumption. It would be great for our space programs, if only to serve as a reminder of what could happen to us if we did not properly prepare for something ahead of time.

I yearn for such catastrophe.

So do I, but remember that mars is the best bet for a second chance if something bad happens to earth that we cannot prevent. Remember that the latest estimates put the impact at 1/1250, which, while bigger than the average, is by no means any large percentage. I would much rather see this happen to venus, or mercury.

[Tuyu]

"If this comet really so big (50 km), the impact will be catastrophic. Collision of such a mass (3.2*1016 kg, if density is 0.5 g/cm3) with a Mars at huge velocity of 56 km/s will release 5*1025 Joules of energy (= 12 millions gigatons TNT). ... Huge debris up to 1 km in diameter will be thrown into space, together with millions Chelyabinsk-like meteoroids - even Martian orbital satellites will be destroyed.

In a scenario like this...seems to me some small (but not infinitesimal) percentage of that debris will randomly be placed on fast-transit trajectories for Earth.

[llearch n'n'daCorna]

In a scenario like this...seems to me some small (but not infinitesimal) percentage of that debris will randomly be placed on fast-transit trajectories for Earth.

Sure, but you're underestimating just how very very big space is.

I mean, you may think it's a long way down to the shops, but... ;-]


Let me put it this way. If you had Mars as an object the size of a grapefruit (7cm diameter), Earth would be an object the size of a soccer ball (13cm diameter). It would be, however, somewhere between 5 and 25 meters away, depending on where in their orbits around the Sun the two planets are. (For those of you in the US, that's something like 5.4 to 27 yards, and something six inches across for Earth, or three for Mars) You need an awful lot of debris to make any of it have any chance of reaching that far thoroughly enough to definitely hit it.

Seriously. Space is big.

(details from this pdf, in case you're interested)

[Ignuus66]

Some of the debree will (eventually) hit earth, but it would probably take hundreds of thousands, if not millions of orbits for any non-dust object to intersect (collide) with earth.
Also about the size of space... It takes 0.13 seconds for a beam of light to encircle the earth, ~1.29 seconds for it to reach the moon, and at MINIMUM 193.25 seconds to reach mars. (not to mention ~46,5 billion years to reach the current edge of the universe)

But in all honesty siding spring hitting mars would be quite the spectacle, but worst case scenarios can and will happen, which is why I hope it is under 30 kms in diameter if it hits.

[Alondro]

Holy crap... that is certainly something to watch for!

If something like that was header for Earth, pretty much the only chance is to hit with a bunch of nukes, then see if we can hit any larger fragments with more nukes. 

We couldn't just do nothing.  A comet that wide is a planet-wide extinction event.  Few large life forms would survive.

[Ignuus66]

Holy crap... that is certainly something to watch for!

If something like that was header for Earth, pretty much the only chance is to hit with a bunch of nukes, then see if we can hit any larger fragments with more nukes. 

We couldn't just do nothing.  A comet that wide is a planet-wide extinction event.  Few large life forms would survive.

the best chance would actually to detonate shaped nuclear charges BESIDE the comet/asteroid and thus push it aside, space is a big place, if done at the distance of mars, a speed difference of 1 m/s would make it not hit. Blasting it into pieces would be futile unless it is made of rubble.

[Alondro]

Holy crap... that is certainly something to watch for!

If something like that was header for Earth, pretty much the only chance is to hit with a bunch of nukes, then see if we can hit any larger fragments with more nukes. 

We couldn't just do nothing.  A comet that wide is a planet-wide extinction event.  Few large life forms would survive.

the best chance would actually to detonate shaped nuclear charges BESIDE the comet/asteroid and thus push it aside, space is a big place, if done at the distance of mars, a speed difference of 1 m/s would make it not hit. Blasting it into pieces would be futile unless it is made of rubble.

But blowing it up would be cooler.  You can't forget the coolness factor!   

[Ignuus66]

Holy crap... that is certainly something to watch for!

If something like that was header for Earth, pretty much the only chance is to hit with a bunch of nukes, then see if we can hit any larger fragments with more nukes. 

We couldn't just do nothing.  A comet that wide is a planet-wide extinction event.  Few large life forms would survive.

the best chance would actually to detonate shaped nuclear charges BESIDE the comet/asteroid and thus push it aside, space is a big place, if done at the distance of mars, a speed difference of 1 m/s would make it not hit. Blasting it into pieces would be futile unless it is made of rubble.

But blowing it up would be cooler.  You can't forget the coolness factor!   

Cosmic shotguns are cool, I agree!