Wapsi Square Forum

Current orbital elements seem to indicate that Comet C/2013 A1 will make a very close approach to Mars in October of next year... closer than the Earth/Moon distance! It seems to be within the realm of possibility that the comet might even hit Mars - the orbit is not well enough determined to rule this out yet, and comet orbits can change due to outgassing pressure as they get closer to the Sun.

http://spaceobs.org/en/2013/02/25/comet ... with-mars/

This one should be worth watching!

Leonid Elinin wrote:On the 19th October 2014, the comet might reach apparent magnitude of -8…-8.5, as seen from Mars! Perhaps it will be possible to accuire high-resolution images from the Mars Reconnaissance Orbiter (MRO).

NEAT!! So even if there's no impact, there might still be some cool "close-up" photos of an actual comet. I wonder if the Mars Rover will be able to see it from the surface.

MerchManDan wrote:NEAT!! So even if there's no impact, there might still be some cool "close-up" photos of an actual comet. I wonder if the Mars Rover will be able to see it from the surface.

I would bet that it will. A visual magnitude of -8 to -8.5 as seen from Mars is really bright!

You can see objects of -4 or brighter during the day, even with the Sun high in the sky. Venus reaches nearly -5 at its brightest. The International Space Station going right overhead ranges from around -4 to almost -6 (it'll be around -4 when it passes over my area in about 20 minutes... I'm going to wander outside and take a look). The brightest supernova ever recorded (in 1066) was estimated at about -7.5, and was said to be "a little more than a quarter that of Moon light."

So, yeah, presuming that Curiosity and/or the Mars Orbiter are still operating then, they should have an incredible ring-side seat to this one.

And, of course, if the "small probability" event occurs, and the comet actually hits Mars... well, I imagine we'll see the flash from here quite easily. "500 km crater". Brrrr...

Dave wrote:And, of course, if the "small probability" event occurs, and the comet actually hits Mars... well, I imagine we'll see the flash from here quite easily. "500 mile crater". Brrrr...

Wow, right. That kind of impact will kick up an obscene amount of ejecta, too - probably a good chance of Mars going dark for a very long time.

That might put that plan of sending a married couple on a swing around Mars to be a bad idea...

jwhouk wrote:That might put that plan of sending a married couple on a swing around Mars to be a bad idea...

Hahaha! I saw that on the news this morning. It would certainly make the trip more interesting.

"Look honey...there's the giant hole where the comet hit!"

Hmmm -- The Hiroshima bomb yield was about 15 kilotons and directly destroyed a mile diameter circle, damaging another mile distant from blast wave and fires.

The Russian meteor detonated at an altitude of about 32 miles with an estimated force of 250 KT (one quarter Megaton), and broke/blew out windows under it's path.

The biggest exploded nuclear device, Tsar Bomba, yielded 57 MT, and knocked people off their feet 300 miles away!

And, if this source is correct, a comet collision with Mars would be in the range of 5-20,000 MT, causing a 300 mile wide crater!! From that, the shock to the Martian crust would cause a planetary quake, no doubt lasting a long time as it circled the planet several times, not only from the impact, but from the rebound as well.

Allowing that the Mars rovers aren't hit directly, their last observations may very well be them being tossed into the air from the ground shock, before burial by weeks, if not months, of falling debris.

Atomic wrote:And, if this source is correct, a comet collision with Mars would be in the range of 5-20,000 MT, causing a 300 mile wide crater!!

you got your numbers wrong... they quoted five to twenty BILLION MegaTons... not five to twenty THOUSAND... just a slight million times too small!

I'd gladly go on that couple's trip to Mars, but I need a wife first.

"A billion here, a billion there, pretty soon, you're talking real money." - Everett Dirksen

Same goes with explosions, sort of!

Atomic wrote:"A billion here, a billion there, pretty soon, you're talking real money." - Everett Dirksen

Same goes with explosions, sort of!

Black hat guy: "What if we tried more power?"

bmonk wrote:Black hat guy: "What if we tried more power?"

Tim Allen would have loved that.