Scientists spot signal from solar-sail craft
Orbital lost and found
Cosmos 1, the experimental, solar sail-powered spacecraft launched yesterday from a Russian submarine, has gone missing. Although faint signals detected by tracking stations seem to suggest that the craft is alive and well, mission scientists don't seem to be able to find it in orbit.
The mission has been jointly funded by a TV production company and the California-based Planetary Society, a space advocacy group founded by the astronomer, science fiction author, and champion of science in general, Carl Sagan. Bruce Murray, co-founder of the Planetary Society, said yesterday that the signals were very good news because it meant the craft was "very likely in orbit".
Mission controllers lost contact with the craft almost as soon as it blasted off yesterday evening, and was presumed lost. However, after some hours, tracking stations in Russia, the Czech Republic and the Pacific Ocean all reported faint signals from the craft.
Scientists suspect that the final rocket burn sent the spacecraft slightly off course, so that although it made it into orbit, it is not in the orbit they expected. If this was the case, ground-based antennae hunting for Cosmos 1 would now be trained on the wrong part of the sky, which would account for the weak signals.
The scientists said they would ask US Strategic Command, normally charged with spotting incoming missiles, or other sky-based threats, for help in tracking down their spacecraft.
The possibility exists that the craft is in a decaying orbit and will eventually spiral down towards Earth.
The original plan was for the craft to orbit the planet, taking pictures for four days, before unfurling its solar sail. The sails would form a 30m circle that would provide a very slight, but constant, acceleration using the pressure of solar photons. Over a period of weeks, the craft's speed should increase so that it achieves escape velocity.
The aim of the project is to show that controlled flight is possible using solar sails. ®