* Astronomy

Update 1

The space walk officially started at 3:31 Eastern time.

Data from a wing leading edge sensor, a post-Columbia system designed to detect possible impacts during launch or in orbit, recorded a 0.12-G "hit" around 5:30 a.m. today.
Impacts registering 1 G "root mean square" are NASA's threshold for concern; although that force is still 10 times less than the force required to cause serious damage.
The Discovery astronauts used the space station's robot arm to inspect the leading edge panels on the shuttle's left wing for the possible micrometeoroid impact.
John Shannon, chairman of NASA's Mission Management Team, said if the data reflected a real impact - and that remains to be seen - it was about 100 times below the threshold expected to cause any real damage.


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Credit NASA TV

The astronauts did not see any obvious signs of damage to the reinforced carbon panels and proceeded to using the shuttle's robot arm to pull a new solar array truss segment from Discovery's cargo bay for handoff to the station arm. The spacer segment will be attached to the end of the station's main truss today.

Source CBS News

Space shuttle Discovery has docked with the International Space Station (ISS) after an inspection showed no visible damage on lift-off.
Astronauts used the shuttle's robotic arm and its cameras to check Discovery's heat shield and upper surfaces after reaching Earth orbit.
The US orbiter linked-up with the ISS at 1706 EST (2206 GMT).

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