PASADENA, California (Reuters) -- Cosmos 1, the first solar sail-powered spacecraft, appears to be "alive" and sending signals to tracking stations but could be in a lower orbit than planned, said mission experts in California, late on Tuesday.
Telemetry data received by three tracking stations in the Pacific Ocean, Russia and the Czech Republic seemed to show that Cosmos 1 made it into orbit, mission staff at the Planetary Society said.
Mission controllers discovered after reviewing telemetry data from the stations that the craft had signaled its passage during what had been believed to be several hours of radio silence, said Planetary Society co-founder Bruce Murray.
"The good news is we have reason to believe it's alive and in orbit," Murray said. "The bad news is we don't know where it is."
Earlier, Cosmos 1 blasted off in a converted Russian ballistic missile from the Barents Sea at the start of a mission meant to show that a group of space enthusiasts could kick-start a race to the stars on a shoestring budget of $4 million.
It initially appeared to be lost almost immediately.
Mission controllers grew worried after several tracking stations along the path of Cosmos 1's intended orbit failed to pick up signs of the 220-pound (100-kilogram) spacecraft.
A portable tracking station in Russia's Kamchatka peninsula, manned by a volunteer with a laptop and an antenna, picked up Doppler data showing the spacecraft's velocity, but the feed was cut off as a "kick motor" apparently ignited to lift the craft into orbit.
The radio silence extended for more than six hours as mission organizers, operating from the Planetary Society's bungalow in Pasadena attempted to track the orbiter's expected path.
Another portable tracking station in the Marshall Islands also was unable to detect the craft's passage. Mission officials said radar scans of the area showed no evidence the spacecraft had exploded.
Members of the Planetary Society, the world's largest private space advocacy group, had hoped the craft, which was intended to deploy a 100-foot (30-meter) petal-shaped solar sail to power its planned orbit around Earth, would demonstrate that sunlight could fuel interplanetary space travel.
A 2001 test launch of the 49-foot (15-meter) solar sails ended in failure because of problems with the launch vehicle separating from the spacecraft.
