TO mark the 25th anniversary of man's first landing on the moon, a special exhibition - 'Our Time in Space' - will be mounted at the Science Museum from December 1 to 11. The display retraces Neil Armstrong and Buzz Aldrin's 'first step' on the moon. 'That's one small step for man, one giant leap for mankind,' Armstrong declared at exactly 2.56 GMT on July 21, 1969. 'We view the 25th anniversary of man landing on the moon as an excellent educational opportunity with historic importance,' said Kevin Rollenhagen of the Omega Watch Company, which is organising the show with the Urban Council. The exhibition, which is on a worldwide tour, will feature the Lunar Excursion Module, the lunar rover and some 100 unique space objects.