AP - Instead of enjoying a relaxing day at the international space station, the space shuttle Discovery's seven astronauts prepared Sunday for an unplanned, fourth spacewalk to get a stubborn, half-retracted solar array to fold up.

AP - NASA moved ahead Saturday with last-minute preparations for its second attempt to get space shuttle Discovery off the ground for the first nighttime launch in four years.

AP - NASA began moving the scaffolding that protects the space shuttle for bad weather early Thursday, despite lingering clouds and other weather woes that cast doubt on whether Discovery will blast off this week.

AP - After decades of scouring Mars in search of geologic evidence of past water activity, scientists believe they have found stunning evidence that water may even now be flowing through the Red Planet's frigid surface.

AFP - Space shuttle Discovery was cleared for Thursday's liftoff after NASA resolved technical concerns, but possible clouds and rain threatened to delay the launch.

Reuters - NASA on Thursday will attempt to launch its third space shuttle mission in six months, a healthy pace the agency needs to maintain to finish work on the International Space Station before the shuttles stop flying in four years.