Hubble pictures Jupiter's 'scar'

Dark disturbance: The WFC-3 has not yet been properly calibrated

Hubble has trained its new camera on the atmospheric disturbance on Jupiter believed to have been caused by a comet or asteroid impact.

The telescope used the Wide Field Camera 3 fitted on the recent shuttle servicing mission to capture ultra-sharp visible-light images of the scar.

The dark spot near the gas giant's southern pole was noticed first by an amateur Australian astronomer.

Some of the world's biggest telescopes have since taken detailed pictures.

Engineers at the US space agency, Nasa, interrupted the post-servicing commissioning of the refurbished Hubble to use the WFC-3.

"Because we believe this magnitude of impact is rare, we are very fortunate to see it with Hubble," said Amy Simon-Miller of Nasa's Goddard Space Flight Center in Greenbelt, Maryland.

"Details seen in the Hubble view show a lumpiness to the debris plume caused by turbulence in Jupiter's atmosphere."

The pictures augur well for Hubble. Its servicing should give it several more years of life.

The WFC-3 will be used to take the deepest images of the cosmos yet.

Astronomers cannot be absolutely sure Jupiter was struck by a space object, but the evidence seems compelling. The scar emerged on 19 July. One estimate of the diameter of the impacting body suggests it may have been hundreds of metres wide.

"This is just one example of what Hubble's new, state-of-the-art camera can do, thanks to the [shuttle] astronauts and the entire Hubble team," said Ed Weiler, Nasa's chief scientist. "However, the best is yet to come."

It is 15 years since Jupiter was famously hit by Comet Shoemaker-Levy 9. It broke up into several pieces as it plunged on to the gas giant. There was prior warning of that event and Hubble took some typically remarkable pictures on that occasion, too.