"Titanic" Asteroid Scars Jupiter

[Judi Lynn]

January 28, 2011 3:41 PM
"Titanic" Asteroid Scars Jupiter

http://i.i.com.com.nyud.net:8090/cnwk.1d/i/tim/2011/01/28/jup3_620x350.jpg

Debris in Jupiter's atmosphere after an object hurtled into the atmosphere on July 19, 2009.
(Credit: NASA/IRTF/JPL-Caltech/University of Oxford)

Astronomers studying a 2009 collision on Jupiter believe that the object which left a big scar on the planet was likely an asteroid the size of the ocean liner Titanic. The finding goes against scientific convention, which generally believed most of the asteroids had been cleared away from Jupiter's gravitational sphere.

"We weren't expecting to find that an asteroid was the likely culprit in this impact, but we've now learned Jupiter is getting hit by a diversity of objects," said researcher Paul Chodas, of NASA's Jet Propulsion Laboratory in Pasadena, Calif. in a statement following the publication of two studies of the Jupiter impact in the journal Icarus.

This event registered big time. Prior to this collision, the only objects that hit Jupiter were thought to be icy comets that got pulled by Jupiter's gravitational force. The resulting explosion is estimated to have released the equivalent of 5 gigatons of TNT, according to the researchers. For comparison's sake, that's roughly 250,000 times more powerful than the atomic bomb that exploded over Nagasaki, Japan, in 1945. And keep this in mind: asteroids of this size smash into the Earth approximately once every 100,000 years, according to NASA.

http://www.cbsnews.com/8301-501465_162-20029949-501465.html

[snagglepuss]

1. I read somewhere it created a crater the size of the Pacific Ocean. nt

[Posteritatis]

5. The scar shown in those pictures is larger than Earth

There wouldn't be a crater, though, since the solid surface is thousands of miles inside the planet.

[snagglepuss]

6. What exactly are we seeing that was scarred? Gas?

Has anyone surmised the size of the crater on the surface?

[Posteritatis]

7. Yeah, you're seeing disrupted cloud and wind patterns

The comet hit Jupiter at a pretty high speed; friction, heat and growing air pressure did their work, and it exploded very enthusiastically after getting a few dozen kilometers into the atmosphere proper. It doesn't take that much force to knock the thinner uppermost atmosphere around, and that explosion packed a lot of force. It would have blown the cloud layers to either side around quite a bit, done some similar things to layers below it, and probably punched a hole in the layers above clear through to space, exposing deeper parts of the planet for at least a little while until things settled.

Jupiter's atmosphere gets pretty enthusiastic at times, even if it isn't as ferocious as Saturn's. It's fluid, like Earth's atmosphere (or ocean), even if it's very very much larger. The atmospheric patterns stabilize after hits like this, though the larger ones like Shoemaker-Levy can take a few months to get things back into order.

There wouldn't be a permanent crater, since gas giants don't really have a surface in a way that we'd recognize. What actually happens is that, because of the air pressure building, the planet's air gets denser and denser until it seamlessly transitions into a liquid a few hundred kilometers in, and that transitions into a solid state thousands and thousands of kilometers further in. Simple air at atmospheric pressures we'd recognize has enough resistance to shatter a comet if it's plowing through it long and fast enough, and Jupiter has that in spades. Pretty much anything near the size of a normal asteroid or comet will be exploding due to heat and pressure in the very uppermost levels of Jupiter before getting anywhere close to the deeper layers.

An impactor of the size mentioned in the article, if it hit Earth in one piece, would probably punch a crater in the 20-40 kilometer range out of the planet. The huge hit Jupiter took in 1994 was closer to a dinosaur-killer in size, and the crater from that one is about 150 kilometers wide. Even that didn't actually hit the "surface" of Jupiter, though.

[snagglepuss]

9. "it exploded very enthusiastically " LOL. Great image.

Thanks so much for such a terrific explanation. After reading it, I did me some googling about Jupiter and discovered it's the 3rd brightest object in the night sky after the Moon and Venus and visible to the naked eye. Who's have thunk that? Also was reminded that Jupiter is the Roman name for Zeus. If had my druthers Earthlings would be toasting him right now. as Zeus seems to be taking good care of the hood:)

To Zeus :toast:


:hi:

[krispos42]

8. I would bet that the atmosphere was pretty roiled up by the impact

and any explosion/concussion. Also, we might be seeing some kind of chemical reaction from the heat of impact

[DCKit]

2. Oh, the humanity!!!!

I know, I know.

[Fumesucker]

3. Jupiter is watched and videoed continuously by amateur astronomers now..

We'll be seeing more such impacts, Jupiter has an enormous gravitational field that sucks in a great deal of cosmic debris.

[kickysnana]

4. Silly that was the Borg craft that the Enterprise took out. I saw it on TV. n/t