July 20, 2009
by The Editors of Sky & Telescope
Anthony WesleyThe image at right, taken by Anthony Wesley, a well-known Australian astrophotographer and planetary observer, shows a new dark marking on Jupiter strikingly similar to the ones left when Comet Shoemaker-Levy 9 crashed into the giant planet in 1994. The dark mark, which appeared suddenly between July 17th and 19th, was quickly confirmed by many other observers. Amateurs have been spotting it in 4-inch and smaller telescopes, at least when Jupiter is high after midnight and the atmospheric seeing steadies up. Wesley has put up a Jupiter impact page with more of his own images.
by The Editors of Sky & Telescope
Anthony WesleyThe image at right, taken by Anthony Wesley, a well-known Australian astrophotographer and planetary observer, shows a new dark marking on Jupiter strikingly similar to the ones left when Comet Shoemaker-Levy 9 crashed into the giant planet in 1994. The dark mark, which appeared suddenly between July 17th and 19th, was quickly confirmed by many other observers. Amateurs have been spotting it in 4-inch and smaller telescopes, at least when Jupiter is high after midnight and the atmospheric seeing steadies up. Wesley has put up a Jupiter impact page with more of his own images.
There is compelling evidence, such as the mark's high infrared brightness in reflected sunlight, that it is black dust resulting from the impact of an asteroid or comet. Jupiter's atmosphere normally contains no dust. Leigh Fletcher twittered from NASA's Infrared Telescope Facility in Hawaii: "This has all the hallmarks of SL-9 in 1994 (15 years to the day!). High altitude particulates, looks nothing like weather phenom." (Keep up with Fletcher's tweets, and read his July 22nd blog post about the impact).
"Here is the spot recorded this morning in marginal seeing," writes S&T's Sean Walker. "It appears to me to be spreading out as predicted." The shot was made with a 14.5-inch reflector and stacked video at 3:46 UT July 21, 2009.
"Here is the spot recorded this morning in marginal seeing," writes S&T's Sean Walker. "It appears to me to be spreading out as predicted." The shot was made with a 14.5-inch reflector and stacked video at 3:46 UT July 21, 2009.
S&T: Sean WalkerThe spot is located near Jupiter's System II longitude 210°. For the predicted times when it will cross the planet's central meridian, add 2 hours and 6 minutes to each of our predicted transit times for Jupiter's Great Red Spot.
If it's really black debris dredged up by an impact, it will probably become spread out horizontally by jet streams in the coming days, and will thin out to invisibility in a matter of weeks and months — as did the marks from Comet S-L 9.
UPDATES:
More amateur photos are posted at the Spaceweather.com pages for July 21 and July 24.
The Jet Propulsion Lab quickly put out a news release with near-infrared (reflected-light) images (also available here if the first site is overloaded.)
Here's a local article from Australia on Anthony Wesley and his discovery.
More amateur photos are posted at the Spaceweather.com pages for July 21 and July 24.
The Jet Propulsion Lab quickly put out a news release with near-infrared (reflected-light) images (also available here if the first site is overloaded.)
Here's a local article from Australia on Anthony Wesley and his discovery.
Keck Observatory takes infrared images.
Here's a fine two-color mid-infrared (i.e. thermal glow) image from the 8.1-meter Gemini North telescope taken on July 22nd. Note the Shoemaker-Levy 9–like splash ring.
BIG UPDATE:
The Hubble Space Telescope team suspended their shakedown and calibration of the recently rebuilt telescope and rushed its new Wide Field Camera 3 into service to image the impact mark. And what a success! The image below resolves far more detail in the mark than any imagery yet from the ground, and will surely tell more about the impact itself. Read all about it, and view more Hubble images.
Hubble's new Wide Field Camera 3 was rushed into service to take this closeup of Jupiter's impact mark on July 23, 2009. In this view north is up.
NASA / ESA / Heidi Hammel / Jupiter Impact Team
The Hubble Space Telescope team suspended their shakedown and calibration of the recently rebuilt telescope and rushed its new Wide Field Camera 3 into service to image the impact mark. And what a success! The image below resolves far more detail in the mark than any imagery yet from the ground, and will surely tell more about the impact itself. Read all about it, and view more Hubble images.
Hubble's new Wide Field Camera 3 was rushed into service to take this closeup of Jupiter's impact mark on July 23, 2009. In this view north is up.
NASA / ESA / Heidi Hammel / Jupiter Impact Team
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