Hubble Back In Its Own Orbit
By Frank Morring, Jr.
JOHNSON SPACE CENTER, Houston - The crew of the Space Shuttle Atlantis released the Hubble Space Telescope early May 19, dropping it off the robotic arm with a full set of functional instruments for the first time since it was launched."Hubble has been released," Atlantis Commander Scott Altman radioed. "It's safely back on its mission of exploration."
Live video of the release, which came at 8:57 a.m. EDT, wasn't available because the Ku-band antenna needed to deliver it was being used in radar mode to track the telescope.
Astronaut Megan McArthur, the robotic arm operator, unberthed the telescope from its mount at 7:26 a.m. EDT and maneuvered it into position above the payload bay for deployment.
Astronauts Mike Massimino and Mike Good were standing by in their extravehicular activity (EVA) undergarments, ready to don spacesuits and go outside to release the telescope manually if the berthing mechanism failed.
Hubble controllers at Goddard Space Flight Center opened the telescope's aperture door, which was closed to prevent contamination of its optics while it was in the payload bay, and the release went off without a hitch.
Hubble now carries the new Cosmic Origins Spectrograph and the Wide Field Camera 3 instruments, as well as two repaired instruments that were largely out of commission before the astronauts arrived - the Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph. A fifth instrument - the Near Infrared Camera and Multi-Object Spectrometer - is out of commission with a stalled cooling system, but the Hubble program has a plan for restoring it to service once it finishes recommissioning the telescope with its new hardware.
Atlantis pilot Greg Johnson slowly backed the orbiter away from the telescope after McArthur opened the grapple fixture holding it to the robotic arm. Once clear of the telescope, he executed a six-foot-per-second burn of the orbiter thrusters to drop into an elliptical orbit with an average altitude comparable to the 200-mile altitude of the International Space Station, where the orbital-debris environment is more benign than the 350-mile altitude where the Hubble operates.
To ensure none of that debris damaged the thermal protection system that will shield them from the heat of re-entry on May 22, the crew was set to use the rest of the day May 19 examining the ceramic tiles and reinforced carbon-carbon panels on the belly, nose and wing leading edges of Atlantis with the robotic arm and the 50-foot-long Orbiter Boom Sensor System.
In case that late inspection turns up irreparable damage, the shuttle Endeavour remains on standby at Kennedy Space Center to mount a rescue mission if necessary. Otherwise, the crew will have most of May 20 off, and will set up May 21 for a first landing opportunity at 10:03 a.m. EDT May 22 at Kennedy.
Hubble photo: NASA
