An amateur astronomer has spotted an object hitting the surface of Jupiter.

Anthony Wesley, an Australian computer programmer with a good reputation among fellow astronomers, spotted a bright flash and alerted professional and amateur sky-gazers to the cosmic collision, which was later confirmed by another amateur astronomer in the Philippines.

"When I saw the flash, I couldn't believe it," said Mr Wesley. "The fireball lasted about two seconds and was very bright."

He gained fame last year when he spotted a scar the size of the Pacific Ocean near Jupiter's south pole, believed to have been caused by an asteroid smacking into the gas giant planet. Using an infrared telescope on Hawaii, Nasa scientists found evidence that Jupiter was apparently struck near its south pole, and credited Mr Wesley.

The latest hit near the equator has not left any visible mark so far, but astronomers are on the lookout.

The absence of a detectable gash and the short impact time have led scientists to believe Jupiter was likely struck by a meteor.

"We've never seen a meteor slam into Jupiter," said Glenn Orton of Nasa's Jet Propulsion Laboratory.

The latest collision should give astronomers a better idea of the size of debris floating in the outer solar system.

In 1994, Jupiter was bombarded by pieces of the comet Shoemaker-Levy 9.