Shuttle ready to land after 'two-week adventure'

Clouds moved in at virtually the last minute and thwarted NASA's effort to bring the space shuttle Endeavour and its crew of seven back to Earth early Wednesday evening.

Mission Control instructed the astronauts to take another swing around the planet and aim for a later, nighttime landing, in hopes that the sky would clear. It will be NASA's second and last shot of the day at bringing Endeavour home.

"Unfortunately, the weather trend did not improve as we had hoped," Mission Control radioed. "We're looking for some improvement," it added.

A landing in darkness would be a rare event.