Article Posted on : - Jun 17, 2010

The mysterious flash on Jupiter was spotted on June 3, 2010. A Hubble Photo

PARIS (AFP): The orbiting Hubble telescope may have explained a mystery streak of light that occurred on the face of Jupiter on June 3, the European Space Agency (ESA) has said.

Astronomers around the world have been abuzz about the flash, with some speculating the Solar System's biggest planet was whacked by a rogue space rock.

The US-European telescope was turned towards Jupiter on June 7, scanning it with ultraviolet and optical cameras, but saw no telltale dark smudges in the swirling atmosphere of Jupiter, ESA said on Wednesday.

“This means that the object didn't descend beneath the clouds and explode as a fireball,” the agency said in a press release.

“If it had done, then dark sooty blast debris would have been ejected and would have rained down onto the clouds.”

Instead, the best hunch is that the object was a large rock that headed towards Jupiter but burned up in its upper atmosphere, above the cloud tops.

It was not big enough to survive burn-up and penetrate deep into the atmosphere, where it would have exploded.

Two such events have been observed in the last 16 years, most famously in July 1994 when a series of fragments from Comet Shoemaker-Levy slammed into the gas giant's disc.

The two-second flash on June 3 was spotted by amateur Australian skygazer Anthony Wesley. It was confirmed separately by an astronomer in the Philippines.

Wesley also observed, in July 2009, an impact on Jupiter from a suspected asteroid.

Jupiter is a relatively frequent site for collisions, given its huge size and the gravitational pull it exerts on space rocks.

Indeed, one theory is that life was able to start on Earth thanks to a “gatekeeper” role played by Jupiter. It took hits from rocks that would otherwise have impacted on our planet with the energy of many thousands of nuclear bombs.