Discovery joins space station despite radar glitch
Even contending with a radar failure, the shuttle Discovery makes a picture-perfect docking with the ISS early Wednesday to kick off a busy resupply mission.
JOHNSON SPACE CENTER, Houston--Commander Alan Poindexter, manually flying Discovery from the shuttle's aft flight deck, guided the space plane to a precision docking with the International Space Station early Wednesday after performing a flawless, "radar-failed" rendezvous.
Approaching from directly in front of the space station, Discovery engaged its payload bay docking mechanism with its counterpart on the front end of the space station's forward Harmony module at 3:44 a.m. EDT as the two spacecraft sailed 220 miles above the Caribbean at 5 miles per second.
"Houston and station, capture confirmed," pilot James Dutton radioed.
"Discovery, arriving," station flight engineer Soichi Noguchi called out, ringing the ship's bell in the Harmony module.
It took about one orbit to complete leak checks ensuring a tight seal between the shuttle and the space station, which together mass 1,043,000 pounds.
Hatches were opened at 5:11 a.m. EDT and the station's six-member crew--Noguchi, Expedition 23 commander Oleg Kotov, Alexander Skvortsov, Mikhail Kornienko, Timothy Creamer, and Tracy Caldwell Dyson--welcomed the shuttle's seven astronauts aboard.
Poindexter, Dutton, flight engineer Dorothy Metcalf-Lindenburger, Stephanie Wilson, Japanese astronaut Naoko Yamazaki, and spacewalkers Richard Mastracchio and Clayton Anderson floated into the Harmony module to smiles, hugs, and handshakes.
The combined 13-member shuttle-station crew is the first to boast four women and the first to include two Japanese astronauts.
The terminal phase of the rendezvous began at 1:06 a.m. EDT with a rocket firing to close the final 9.2 miles between the shuttle and the station. Poindexter maneuvered Discovery to a point 600 feet directly below the lab complex and then performed a slow back-flip maneuver to expose the ship's heat shield to the station.
While the shuttle's Ku-band antenna/radar system was out of action because of an earlier malfunction, TV from the station provided a spectacular bird's-eye view of the dramatic maneuver as Discovery passed high above Southeast Asia.
Kotov and Creamer snapped 364 pictures using digital cameras equipped with 400mm and 800mm lenses to document the condition of the protective tiles on the shuttle's belly. The photos will be downlinked to Houston for a detailed analysis.
After the rendezvous pitch maneuver was complete, Poindexter guided Discovery up to a point about 300 feet directly in front of the space station, with the shuttle's nose pointed toward deep space and its open payload bay facing pressurized mating adapter No. 2 on the front end of Harmony. From there, he flew the shuttle to a problem-free, on-time docking.
Poindexter had no problems completing the rendezvous without the shuttle's Ku-band radar system.
"It was a great day in space," said Flight Director Richard Jones. "We got successfully docked to the International Space Station and we're off to the races with respect to the rest of the docked mission...The 'radar-failed' (rendezvous) procedures went very well, the crew flew the rendezvous profile flawlessly, and (they) made it look easy."
As soon as hatches were opened between Discovery and the station, Wilson handed off a computer hard drive loaded with stored imagery collected during an extensive inspection of the shuttle's nose cap and wing leading-edge panels that was carried out Tuesday.
Because of the Ku-band antenna problems, the data could not be downlinked in real time. But using the station's Ku-band communications system, engineers expect to get all the imagery down to the ground by noon.
"The data collection process with respect to getting all the imagery down has started," Jones said. "Once the hatches were opened, we gave the ISS crew the flight day two inspection data that we had collected and they were starting to downlink that as I was walking over."
Jones described Discovery's rendezvous pitch maneuver as "just a beautiful thing to see, it's almost poetry."
"It looks like the vehicle seems to be, in general, in great health," he said. "We'll obviously let the experts look at the detailed imagery and confirm that. But things seem to be going very well."
Overnight Wednesday, the astronauts plan to move a cargo module, loaded with more than 17,000 pounds of supplies and equipment, from Discovery's payload bay to the space station.The first of three spacewalks to replace an ammonia coolant tank on the station's solar power truss is planned for early Friday.