Florida ? Space shuttle Discovery’s astronauts steered closer to the international space station for a linkup today while checking their ship for any signs of launch damage.

The routine survey began early Saturday evening and was expected to last well into the night.

NASA officials say no fuel tank debris was observed hitting Discovery during Friday’s midnight liftoff.

But the shuttle’s most vulnerable areas — the wings and nose — still needed to be checked with lasers and cameras on a boom attached to the robot arm.

In addition, the shuttle’s underside will be photographed in detail by the space station residents tonight, right before the two craft meet.