Tuesday, December 21, 1999 – 11 p.m. CST
After a 30-orbit chase, Discovery astronauts completed a successful rendezvous Tuesday evening with the Hubble Space Telescope, grappling it with the robotic arm and latching it into the orbiter’s cargo bay.
Controllers at Goddard Space Flight Center had placed the space telescope in an attitude with its closed aperture pointed toward Earth. Commander Curt Brown guided Discovery through an approach from below and fly-around. Then, Mission Specialist Jean-Francois Clervoy reached out with the shuttle’s robotic arm to grip a grapple fixture on Hubble. The grapple was made at 6:34 p.m. Central time, one day, 23 hours and 44 minutes after Discovery’s launch from the Kennedy Space Center in Florida.
Clervoy used the arm to rotate the space telescope and bring its base into the cargo bay. Hubble, gleaming silver in its Mylar insulation flanked by golden-colored solar arrays, was firmly attached to the Flight Support System in Discoveryís cargo by a little after 7:30 p.m. Hubble is as tall as a four-story building. With a maximum diameter of 14 feet, it is about the size of a railroad tank car.
The Flight Support System is a U-shaped device with a circular platform between the U’s arms now supporting the space telescope. The system provides power from Discovery to the telescope and can rotate and tilt it to facilitate access to its various compartments by space-walking astronauts. An initial, carefully choreographed survey using a camera at the end of the robotic arm was made. Camera surveys of Hubbleís condition will continue during the crewís sleep period, scheduled to begin about 12:50 a.m. Wednesday.
The first of three planned space walks to repair and upgrade Hubble equipment is scheduled to begin at 1:40 p.m. Wednesday, though astronauts may get an early start. If they can get ahead of schedule, they may be able to perform some tasks that had been scheduled for the cancelled fourth spacewalk.
On Wednesday, Mission Specialist and Payload Commander Steve Smith and Mission Specialist John Grunsfeld will first replace the telescopeís three Rate Sensor Units. Each contains two gyroscopes. The second major task is installation of six Voltage/Temperature Improvement Kits between Hubbleís solar panels and its six 10-year-old batteries. The cell telephone-sized kits are designed to prevent any overheating or overcharging of those batteries.
Discoveryís systems continue to function well as the astronauts wind up final preparations for Wednesdayís space walks and prepare for sleep. The spacecraft was in an orbit with a high point of 380 statute miles and a low point of 355 miles.
The next Mission Control Center status report will be issued at 11 a.m. Wednesday or as events warrant.
