In August 1960, NASA launched its first communications satellite, Echo 1 00 and now, fifty years later, NASA has achieved another first by placing the ARTEMIS-P1 spacecraft into a unique orbit behind the moon, but not actually orbiting the moon itself.

A SPY satellite the size of a small bus could come crashing back to Earth at the end of next month. US technicians say the satellite, which is feared to contain highly toxic rocket fuel, has lost all power and is out of control.

Near the end of the mission of Apollo 16, on April 24, 1972, just before returning back home to Earth, the three astronauts released one last scientific experiment: a small "subsatellite" called PFS-2 to orbit the Moon about every 2 hours. Then something bizarre happened.

I'm not sure Cassius should be given precedence over Mondas (Letters, March 18). Confusingly, Mondas is described as Earth's twin in an elliptical orbit beyond the solar system. For my money, if it orbits the sun, it's part of the solar system.

European Space Agency -- The spacecraft is now completing its 50th orbit and has completed more than 560 hours in space. The main activity of the last week has been to repeatedly use the electric propulsion engine to gradually alter the spacecraft's orbit.