Images of Philae Lander's Historic Comet Bounce Revealed by ESA

The discovery came thanks to painstaking follow-up analysis of a series of pictures ESA had released on Friday, the agency said.

The photos appeared to show only a trail of dust kicked up by Philae when it touched down and rebounded after a pair of harpoons, designed to anchor it to the comet's surface, failed to work.

But closer scrutiny of the images has shown a bright dot that is Philae as well as a dark dot made by its shadow as it zooms upwards in the rebound.

"It appears as a couple of brighter pixels closely accompanied by its shadow in the form of a couple of darker ones just below, both to the right of the diffuse dust cloud shadow," ESA's Rosetta mission said in a blog post.

The discovery came from hours of patient work by flight dynamics specialist Gabriele Bellei, the posting said.

A science lab laden with 10 instruments, Philae was sent down to Comet 67P/Churyumov-Gerasimenko by its mother ship Rosetta, after a 10-year trek that covered 6.5 billion kilometres (four billion miles) around the inner Solar System.

After its first bounce, it is believed Philae landed and bounced once more before settling around a kilometre from its target site.

The lander found itself at an angle and in the shadow of a cliff, which meant its solar panels were unable to capture the sunlight it needed to recharge its batteries.

But ESA says Philae successfully carried out its scheduled research programme thanks to a battery that had enough charge for 60 hours' work.

Philae has now gone into standby mode for lack of power. Mission managers still have some hope it will revive as the comet races closer to the Sun, bringing greater illumination.

Approved in 1993 and launched in 2004, the Rosetta mission aims to uncover the chemical and physical secrets of comets primordial clusters of ice and dust that may explain the origins of the Solar System and, say some, of life on Earth.