Yet another asteroid impact has been recorded on Jupiter by amateur astronomers, raising the possibility that these are occurring more frequently than was imagined.
Japanese observer Masayuki Tachikawa, of Kumamoto city, recorded a bright flash on the planet on August 20 with a Philips Toucam Pro2 webcam attached to his telescope, a 150mm refractor.
It was confirmed by a video from another Japanese observer, Aoki Kazuo, as having happened at 18h 31m 56s UT.
The event appears to resemble another bright flash that was independently observed by two different amateur astronomers on June 3, just two and a half months ago.
And that came after one of those observers, Anthony Wesley, of Broken Hill, Australia, recorded a dark spot that seemed to have been left by another impact a year earlier in July 2009.
There are suggestions that the latest flash, which happened on the edge of the dark North Equatorial Belt, might have been caused by an asteroid up to 1km wide hitting Jupiter, but that would appear to be purely guesswork at this stage.
As the biggest planet in the solar system, lying on one edge of the main asteroid belt, Jupiter is bound to be something of a magnet for smaller objects. This year’s impacts are little more than fleabites to Jupiter and comparable to a large pebble producing a brilliant fireball in our own atmosphere.
Last year’s dark spot, which was about the size of the Earth, suddenly appeared near the planet’s south pole and resembled markings left when a disintegrating comet hit Jupiter 15 years earlier.
That string of impacts was predicted in advance as astronomers watched the comet, Shoemaker-Levy 9, break up to resemble a string of pearls. Hubble took images of the scars left by both impact events.
However, nothing was seen following the flash that occurred in June, suggesting the impactor was swallowed up by the gas giant’s clouds without an ill effects.
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