After a Month, Hubble Is Clicking Away Again
Friday, October 31, 2008
The Hubble Space Telescope is working again and taking spectacular pictures, officials said yesterday, but a planned space shuttle mission to repair and upgrade the orbiting observatory will be delayed a second time and will not take place until May at the earliest.
The telescope had been shut down for a month because a key instrument failed, but engineers succeeded this week in switching to a backup and getting the main camera working again.
The failure of the "data formatter" delayed a shuttle mission originally planned for October while technicians prepared a third spare that has been in storage at the Goddard Space Flight Center. That process is taking longer than anticipated, however, forcing NASA to delay the shuttle mission again from February well into 2009.
Hubble program manager Preston Burch said the newly restored capabilities on the Hubble should hold up until astronauts can reach the observatory next year.
The Space Telescope Science Institute in Baltimore, which operates the Hubble for NASA, said the new images captured by the Wide Field Planetary Camera 2 were a "perfect 10," equal in quality to what the telescope was delivering before one of its two science data formatting instruments failed.
Several weeks of intense efforts to switch over from the failed "data formatter" to an 18-year-old, on-board duplicate that had never been used the process succeeded this week. The first new images were taken on Oct. 27 and 28 and show a pair of galaxies about 400 million light-years from Earth in the constellation Cetus. The astronomers said one galaxy appears to have passed through the other.
The Hubble, which is jointly operated by NASA and the European Space Agency, has revolutionized astronomy since it became fully operational in 1993. The planned fifth repair mission, which NASA says will be the last to reach Hubble, is expected to make the observatory more powerful than ever and keep it running until 2013.
The Hubble's Advanced Camera for Surveys is also working again but is able to pick up only ultraviolet light, said Space Telescope Institute spokesman Ray Villard. The visible light capability went out a while ago and is scheduled to be fixed during the repair mission.
"We're now back where we were before the formatting instrument failed," Villard said.
Almost every major component of the Hubble has a spare, and the second formatter is now doing all the essential work related to translating data collected by the telescope into a form that can be transmitted to Earth. NASA officials think the third formatter now being worked on at Goddard must be installed to keep the Hubble working.
The issue is significant enough that NASA's Astrophysics Division Director Jon Morse said it is possible that the repair and upgrade mission would be scrubbed if the third formatter cannot be brought up to specifications. But he said he remains confident that the instrument, which had been partly disassembled during in a Goddard clean room, will be fully restored.
The spare has to be repaired and put through almost three months of assessments that include electromagnetic interference checks, vibration tests and extended time in a thermal vacuum chamber. If all goes well, officials said, the unit will be delivered to the Kennedy Space Center in early April for loading onto the space shuttle.