A UFO crashes in Pennsylvania. Was it a secret Soviet satellite -- or something far more dangerous? On Mercury, NASA finds the impossible: frozen water. A strange object causes a skyscraper-sized shadow on the surface of Mars's largest moon. What is it?
A Russian probe discovers something has disturbed the lunar soil before the US or the USSR got there. Did Nazis get there first? Have scientists detected a laser signal from a planet capable of supporting life? Is there really a Bermuda Triangle of Space?