Possible comet/asteroid impact on Jupiter?

[rybanis]

http://www.astronomynow.com/news/n0907/20jupiter/

How very interesting. Not a moon shadow, very dark - almost jet black!

I believe that would be really cool if it is what they think it is.

 

[rybanis]

http://spaceflightnow.com/news/n0907/20jupiter/

UPDATE: Evidence is pointing more and more towards an impact. Look at the infrared pictures. Also, there seems to be a "debris" splash on one side of the plume. This just keeps getting more and more interesting.

I would suggest anybody with good seeing and large apertures look at Jupiter, I have a feeling something standing out like that could be resolved.

 

[3488]

Jupiter been hit again?

On Sunday 19th July 2009 a largish dark spot has appeared near Jupiter's South Pole.

Article & images here.

Spaceflightnow.com article.

Andrew Brown.

 

[freya]

Re: Jupiter been hit again?

I can still remember the awe felt when observing the Shoemaker/Levy impacts - comparisons will be made, be interesting to see if there are any subsequent impacts. The date of impact is a good coincidence huh.

 

[yevaud]

Re: Jupiter been hit again?

Duplicate thread. I'll merge this with the existing one...

 

[dragon04]

Absolutely fascinating. This gives one pause to consider just how often Jupiter eats one for the Team.

 

[aphh]

Absolutely fascinating. This gives one pause to consider just how often Jupiter eats one for the Team.

I'm sure there have been many with our name on them, that Jupiter sucked in. That planet is our 800 lbs gorilla of planetary security.

 

[xXTheOneRavenXx]

I do have one quick question regarding this impact. Since Jupiter is mostly just Hydrogen & Helium with a possible core of metallic hydrogen & rock that makes up between only 3-15% of the planets total mass, and given the impact occured so far in the southern region, (besides the tremendous gravity of Jupiter) why wouldn't the object just impact the gas and come out the other side via momentum? Or at least wouldn't we see affects in the gas on the opposite side of the southern hemisphere?

 

[CalliArcale]

Mostly because it gets disintegrated. Gas isn't insubstantial, as the space shuttle Columbia tragically demonstrated. Spacecraft reentering our own atmosphere often do not even reach the ground, and our atmosphere is *nothing* compared to Jupiter's, which is so dense that probes into it would be crushed before they reached whatever is in the middle.

This object was likely orbiting Jupiter before it struck. (So was Comet Shoemaker-Levy 9, actually. Jupiter had captured it into a highly elliptical and unstable orbit which ultimately decayed.) There's no way it had enough energy to get all the way through. Its momentum will have been converted largely into heat energy, rapidly decelerating it and most likely vaporizing it, just like a meteor in our own atmosphere, but on a much larger scale.

 

[MeteorWayne]

You answered your own question Raven

It's the tremendous gravity of Jupiter.

Also, since AFAIK, this object was not detected before impact, we have no idea what it's path toward the planet was. It could have been boring on straight toward the southern hemisphere.

Further backsearches of images may reveal the asteroid/comet that made the impact and we will learn more.

If you recall, Shoemaker Levy 9 approached the south pole at an oblique angle, and none of them popped through to the other side. Don't forget, whatever the object, it was vaporized during the impact, and isolated gas/plasma particles have little individual momentum when confronted with a dense atmosphere.

 

[xXTheOneRavenXx]

I suppose you right Calli & Wayne. For a moment I was thinking a straight on impact, with the increased velocity from the gravitation pull of Jupiter might cause either a object to pass through a section of Jupiter or at least cause an affect in it's weather convection on the opposite side of the impact point. But ya, Jupiter does have intensive gravity. Sorry for the "lacking brain" moment Been a busy day.

 

[MeteorWayne]

Actually I think the more significant factor is that the object is vaporized on impact with the atmosphere.

Unless it skims the very outer reaches of the atmosphere (much like the Grand Teton fireball in 1972 did with earth) it ain't gonna survive. Much larger asteroids that impact earth don't even make it to the ground, much less the other side of the atmosphere, and earth's is realy really puny by comparison....

 

[xXTheOneRavenXx]

Yes, but unless I'm looking at these images wrong, the "Dark spot" looks to be several kilometer's in diameter. Could an object that size not survive the crushing gravity? Just a thought really. Kind of going against my knowledge and intuition. I am sure even an earth sized object wouldn't survive passing through Jupiter either.

 

[CalliArcale]

Yes, but unless I'm looking at these images wrong, the "Dark spot" looks to be several kilometer's in diameter. Could an object that size not survive the crushing gravity? Just a thought really. Kind of going against my knowledge and intuition. I am sure even an earth sized object wouldn't survive passing through Jupiter either.

The dark spot isn't the object itself -- it's the disruption in Jupiter's cloud deck. Sort of a "cloud crater", you might say.

Consider this: Meteor Crater is believed to have been created by a nickle-iron meteorite about 50 meters across. The crater itself is almost 400 meters across. And that's in rock, which is more, ah, "reluctant" to deform than gas. So the impactor must have been a lot smaller than this dark spot.

It is very reminiscent (for obvious reasons) of the Shoemaker-Levy 9 impacts. Those fragments, which left some marks bigger than this one, were not more than 2 km across.

 

[robnissen]

This is a further example of why there may be very little intelligent life in the Milky Way. 1) Life as we know it requires liquid water, so most planets are eliminated right there. 2) You need a goldilocks star, one that is not too big, (it burns out in a few hundred million years before life evolves), or too small (any planet in the liquid water zone would be both tidally locked and constantly being fryed by the frequent flares of a red dwarf), most stars are therefore immediately eliminated. 3) In addition, it is very possible that the moon helped intelligent life evolve on the earth by creating tides that made tidal pools where creatures were alternatively exposed to air and water. To have such tides you need a fairly large moon, which will eliminate more planets. 4) Next plate tectonics seem to help life evolve, they provide energy sources, as well as various chemicals and gasses, as well as varying elevations to create land and sea. It seems likely, that if earth hadn't lost much of its crust in the collision that created the moon, the earth would either not have plate tectonics, or the plates might have stopped by now (and intelligent life has only been here a few hundred thousand years). Thus, you need a planet that had a large collision early in its life to lose its crust so that it would have plate tectonics for billions of years. 5) And finally, the reason for this post, you need a big hulkin Jupiter type planet to catch all the asteroids and comets that otherwise would wipe out intelligent life. It is sad to think that we may be alone in this galaxy (that is not to say that microbe life could not be frequent).

 

[R1]

False color image. The spot is the size of Earth's Pacific Ocean.

from SDC page:

http://www.space.com/php/multimedia...chis+(SETI+Institute/UCB),+James+Graham+(UCB)


Pacific Ocean:

 

[xXTheOneRavenXx]

The dark spot isn't the object itself -- it's the disruption in Jupiter's cloud deck. Sort of a "cloud crater", you might say.

Consider this: Meteor Crater is believed to have been created by a nickle-iron meteorite about 50 meters across. The crater itself is almost 400 meters across. And that's in rock, which is more, ah, "reluctant" to deform than gas. So the impactor must have been a lot smaller than this dark spot.

It is very reminiscent (for obvious reasons) of the Shoemaker-Levy 9 impacts. Those fragments, which left some marks bigger than this one, were not more than 2 km across.

Oh, I knew it wasn't a crater Calli, but as you said "it's the disruption in Jupiter's cloud deck". How much of an gravitational affect would have been exerted on this object prior to it entering the actual atmosphere on Jupiter? Also, would the gas disturbance spread out less throughout Jupiter's atmosphere making it more difficult to get an actual size measurement? After all, the wind speed on Jupiter is approx 360km/hr.

 

[freya]

the "Dark spot" looks to be several kilometer's in diameter. Could an object that size not survive the crushing gravity?

Just a note on the scale of things 'out there'. The Jovian diameter is is about 10.5 times that of the Earth. By my reckoning, the spot is approx half the Earth's diameter in size, I would put it at about 5000km in diameter.

 

[CalliArcale]

Oh, I knew it wasn't a crater Calli, but as you said "it's the disruption in Jupiter's cloud deck". How much of an gravitational affect would have been exerted on this object prior to it entering the actual atmosphere on Jupiter? Also, would the gas disturbance spread out less throughout Jupiter's atmosphere making it more difficult to get an actual size measurement? After all, the wind speed on Jupiter is approx 360km/hr.

I doubt that the object's gravitational field would have had much affect on Jupiter's clouds, at least compared to the vicious winds that whip around the planet. No, I think this would be created purely by the kinetic energy of the impact.

As far as estimating the size of the impactor, I really have no idea what astronomers will come up with, but I imagine it will be a pretty loose estimate. Too many variables. It's hard enough to estimate how big an Earth impactor was. The only reason we know how big the SL-9 fragments were was because astronomers were able to observe them prior to the impact and estimate their size by more traditional methods (like estimating albedo and working out a likely size based on that and the object's apparent magnitude).

 

[xXTheOneRavenXx]

Well, I suppose they could take how the impact of the various sized pieces of SL-9 individually changed the cloud desk at their impact points, and extrapolate that information to get a "closer to" approximation for the size of this impactor. I'm sure many, many pictures were taken of that event to use as a kind of "Impactor size/cloud deck disturbance" scale.

 

[MeteorWayne]

Unfortunately, size (and mass) is hard to correlate with impactor size without knowing the velocity of the impact. If you recall, the kinetic energy formula is: 1/2 mass times the velocity squared (1/2m*v^2) so without knowing the impact speed, any mass estimates are pretty speculative. As I said a few posts ago, hopefully some backtracking on asto images will find the object before impact, so the orbit (and hence the impact velocity) can be determined.

Then it wall all be much easier to accurately understand the impact.

 

[Bill_Wright]

The entire disruption is now larger than the Earth. The impact object was likely 1/10th the size of the initial disruption, which was about 1/2 the size of the Earth. Those are assumptions, not calculations. At the least, this was a continent killer. At the worst, it might have been a civilization killer. Would anyone of us survive that? I give those odds as about 60/40 against. Now I guess there is a tiny chance that the disruption came from below, not above. I give those odds as 95/5 in favor of above, giving me a little wiggle room, just in case. At any rate it is clear proof that we must learn how to manage all such events, whichever direction they might come from. The only way to do that is to make asteroids and comets manageable objects, and find at least one that we can use to study events and learn how to manage events from below. We dare not Alpha test these techniques on a habitable planet without doing so on one or more objects from the Asteroid or Kuiper Belts, or from the Oort Cloud. Just because we might be able to go to Mars first doesn't mean we should. The primary rule for any species is to survive. To do so requires maturity, part of which is picking substance over style. In my opinion we should do no more stunts or take no baby steps until we are 100% sure we can survive.
-- Bill

 

[yevaud]

I would seriously doubt that the disturbance was caused by any event "from below." Those sort of events - usually hot spots - cause cyclonic storms, not "holes" in the upper atmosphere. And having been working at an observatory during Shoemaker-Levy, and hence able to view the results, this does resemble the aftermath of the aforementioned event.

Btw, it was simply not possible to actually watch the impacts proper during Shoemaker-Levy. Each object impacted beyond one limb of the planet. What we DID see later was the spectacular glowing dome of light from the collision energies, when they re-appeared around the approaching limb; in one case, spectacularly so.

 

[General_Kenobi]

As we search for life beyond our solar system, I think we should look for systems that, like ours, have these massive protectors (Jupiter, Saturn, etc.) to help prevent some of the potential impactors to worlds within the so-called habitable zone. How many of these things have been gobbled up by our gas giants over the past billion years? And how many of those would have ended life on Earth had they gotten through? Who knows, gas giants sitting in the outer solar system could be one of the main keys to sustainable & evolutionary life. Maybe it's as simple as these planets being necessary. Any thoughts, anyone?

On another note, anyone else have a problem with the "15 years to date" thing? I prefer 1.25 Jupiter years, or whatever it actually is...I know it's close, though. When I hear "15 years to date," I'm automatically thinking Jupiter is in its same orbital position as when SL9 hit her. Not true.

 

[AeroSpaceGhost]

Perhaps it is the obelisks about to transform Jupiter into a star. :mrgreen:

Just a "fun" thought...