European space experts said today they had successfully reawakened a fridge-sized robot designed to make the first-ever spacecraft landing on a comet.
The 100-kilogramme (220-pound) Philae lander was revived after more than three years of deep space hibernation, in a key phase of a billion-dollar mission launched over a decade ago.
France's National Centre for Space Studies (CNES), in Paris, said that the spacecraft had re-established contact with Earth, and that an "initial signal was received at 3.00 pm (1400 GMT) today at mission control in Cologne, Germany".
A Twitter account set up for the robotic lander said: "My controllers say that I am in quite good condition after 39 months of hibernation.
"My new software has uploaded perfectly. I'll be taking a little rest now! Talk to you soon."
The lander is travelling aboard an unmanned probe called Rosetta which will make an historic rendezvous with Comet 67P/Churyumov-Gerasimenko, currently 650 million kilometres (400 million miles) from Earth, this summer.
