A recording of Elton John's "Daniel" woke the crew up, a musical request from the wife and two sons of European Space Agency astronaut Thomas Reiter, who is to become a member of the space station's crew after the shuttle docks.
Reiter - who has a son named Daniel - will spend six months living on the space station, bringing the size of the crew to three people for the first time in three years.
The crew size was reduced in the years after 2003's Columbia accident when NASA's shuttle fleet was grounded. Russian vehicles weren't large enough to keep the space station supplied for more than two people.
The docking with the space station, orbiting about 220 miles above Earth, comes a day after in-flight inspections of Discovery by its crew, using cameras attached to a 50-foot boom, revealed no major damage from the launch.
There will be one more opportunity to inspect the space vehicle before docking.
At about 600 feet below the space station, Discovery's commander, Steve Lindsey, plans to maneuver the space shuttle into a back flip so that space station crew members Pavel Vinogradov and Jeff Williams can take pictures of its belly for signs of damage.
The pitch maneuver was performed for the first time by commander Eileen Collins during last year's flight of Discovery.
Wednesday's inspection by the astronauts uncovered a thermal tile filler poking about a half-inch out of the belly of Discovery. Deputy shuttle program manager John Shannon said better data should be available Thursday but for now, engineers do not believe the dangling fabric will pose a danger for re-entry or require repairs. Last summer two similar strips had to be removed in orbit.
Photos showed two areas of small foam loss around the ice frost ramps on Discovery's tank, but the foam loss was too small to be a danger to the shuttle, Shannon said.
Last month, NASA's safety director and chief engineer recommended against launch until the area around those ramps was fixed. A repair plan is still being designed.
The mission for Discovery's crew is to test shuttle-inspection techniques and deliver supplies to the international space station. Astronauts Piers Sellers and Michael Fossum plan to carry out two spacewalks, and possibly a third, which would extend the 12-day mission by a day.