The aging Hubble telescope, which has peered into the depths of space for 18 years was due to for an upgrade and a repair soon, but it looks like that will have to wait for as much as six months. Critical electronic equipment, the Control and Data Handling Unit, failed leaving scientists and astronauts to wait until a replacement unit is prepared.

The Control and Data Handling Unit is a computer which manages the Hubble Telescope’s five main scientific instruments, receiving data from them using a microprocessor-based Control Unit/Science Data Formatter (CU/SDF), and formats it into packets to be transmitted down to Earth to be interpreted. The Hubble is equipped with two of these units, one Side A, the main system, which failed, and one side B, a redundant backup system.

All attempts by scientists to reset or at least obtain a memory dump from the Side A formatter have met with failure, and they are forced to build and install a replacement. Until then, the science team is attempting to switch operations to side B. The backup formatter hasn’t been turned on since the telescope’s launch 18 years ago, and even if turning it on did go according to plan, all the other instruments in the telescope would have to be rerouted to output to it. While in theory, this could be achieved from ground control at the Goddard Space Flight Center in Greenbelt, Maryland, this has never been attempted, and it is unknown if it will succeed. If it doesn’t, the Hubble telescope will be totally inoperative until the faulty computer is replaced.

Scientists have suggested a reason for Side A’s failure: The Hubble space telescope operates at very high temperature, and this could have accelerated the equipment’s decay, and so could have prolonged exposure to open space radiation.

Astronauts from the shuttle Atlantis were scheduled, over five spacewalks, to install an ultraviolet spectrograph to the Hubble telescope, as well as a new wide-field camera, a new set of gyroscopes, and repair electronic failures on the Space Telescope Imaging Spectrograph and the Advanced Camera for Surveys. This set of upgrades was to extend the Hubble’s operational life for about another five years before it was finally allowed to drop from orbit and burn in the atmosphere.

Now the mission, which was due for an October 14 liftoff, and was going to put seven astronauts in orbit for a period of 11 days will be delayed till February, maybe even April next year due to a change in objectives, as the replacement Side A formatter is prepared, and astronauts are trained in its installation.

Despite the frustration involved, Ed Weiler, associate administrator of NASA's Science Mission Directorate looks on the bright side, saying that it’s better that the formatter failed now, rather than after the repair mission.