LONDON British tenor Russell Watson has discovered his voice has been used on the space shuttle Endeavor to wake the astronauts up, he said on Sunday.

"When I signed my record deal, they wanted rights for the world and the universe - they obviously knew something I didn't," Watson told Britain's Press Association News Agency.

NASA decided to play the theme tune which the singer recorded for the forthcoming "Star Trek" series to the astronauts as an alarm call.

Endeavor last week completed its mission after six months in orbit during which its crew fitted a giant robotic arm to the international space station.

Watson recorded the song "Where My Heart Will Take Me" as the theme to the show "Star Trek: Enterprise".