Jupiter impact spot still visible?

jerry warner wrote in :

Does anyone here know"?
Is anyone here doing astronomy?
Is anyone here looking at Jupiter?
Any non spammers left here?

smile-
Jerry



http://science.nasa.gov/headlines/y2....htm?list74817


What Hit Jupiter?

08.03.2009

August 3, 2009: It began with a furrowed brow, a moment of puzzlement,
quickly dismissed.

The date was July 19, 2009. Amateur astronomer Anthony Wesley was
photographing Jupiter from his backyard observatory in Murrumbateman,
Australia, when something odd caught his eye.

"My attention was fixed on the Great Red Spot, which was setting
beautifully over Jupiter's horizon," recalls Wesley. "I almost didn't
notice the dark blemish near Jupiter's south pole, and when I did, I put it
out of my mind."

It's just another dark storm on Jupiter.

"That's what I thought at first, but something about the dark mark puzzled
me, it didn't look right, and I couldn't stop stealing glances at it."

Slowly, Jupiter's rotation turned the blemish toward Earth, Wesley got a
better look at it, and the truth struck him like a thunderbolt.

It was an impact mark. Something hit the giant planet!

"I had seen the scars caused by fragments of Comet Shoemaker-Levy 9 hitting
Jupiter in 1994, so I knew what an impact looked like," he says. "After I'd
convinced myself that this was real, I could hardly use the computer. My
hands were shaking. It was quite unbelievable."

He quickly emailed his photos to friends and colleagues around the world,
and within hours telescopes great and small were turning toward Jupiter to
photograph the aftermath of a powerful collision.

"We believe it was a comet or asteroid measuring perhaps a few hundred
meters wide," says Don Yeomans of NASA's Near-Earth Object Office at JPL.
"If something of similar size hit Earth—we're talking about 2000 megatons
of energy--there would be serious regional devastation or a tsunami if it
hit the ocean."

In a stroke of luck almost as big as Wesley's, JPL astronomers Glenn Orton
and Leigh Fletcher were already scheduled to observe Jupiter on July 20th,
barely a day after impact, using NASA's Infra-red Telescope Facility (IRTF)
atop Mauna Kea in Hawaii. The 3-meter telescope revealed a fresh cloud of
debris about the size of Mars floating among Jupiter's clouds.

"The object, whatever it was, exploded in Jupiter's upper atmosphere," says
Orton. "It blew itself to smithereens. What we're seeing now are bits and
pieces of the impactor and possibly some strange aerosols formed by shock-
chemistry during the impact."

On July 23rd, the Hubble Space Telescope took its first pictures of the
blast site. Hubble was still undergoing checkout and calibration following
the STS-125 servicing mission in May, but this event was too big to skip.
Space Telescope Science Institute director Matt Mountain allocated
emergency telescope time to a team of astronomers led by Heidi Hammel of
the Space Science Institute in Boulder, Colorado.

As usual, Hubble photos stole the show. They revealed a swirling maelstrom
of dark cindery debris jostling with natural storms near the top of
Jupiter's atmosphe

"The debris cloud is lumpy because of atmospheric turbulence," explains
planetary scientist Amy Simon-Miller of the Goddard Space Flight Center.
"Polar winds blowing 25 m/s (~55 mph) are causing it to spread out and grow
larger. This will make the cloud even easier to see through backyard
telescopes."

Judging from the behavior of the Comet Shoemaker-Levy 9 impacts fifteen
years ago, she estimates that the 'Wesley debris cloud' could remain
visible for many weeks to come. Researchers will put the time to good use.
Further studies of the cloud might yet reveal the great unknown:

"We just don't know," says Yeomans. "No one saw the object prior to
impact."

Indeed, there was no warning. The object emerged from darkness, unknown and
uncatalogued, and—wham!—before anyone could photograph the body intact, it
had become a cloud of debris. (There is a lesson here for Earth, but that
is another story.)

The cloud's chemical composition holds clues to the nature of the impactor.
Orton says ground-based observers are now analyzing light reflected from
the cloud to figure out what it is made of. "If the spectra contain signs
of water, that would suggest an icy comet. Otherwise, it's probably a rocky
or metallic asteroid."

Meanwhile, it's a big dark mystery—the kind that Wesley can't take his eyes
off of. "I am still observing Jupiter almost every night using my 14.5 inch
telescope," he says. "The cloud is expanding and taking on some interesting
shapes."

"I wonder," he says, "what will happen next?"