Hubble's main camera shuts down

BALTIMORE -- The main camera on the Hubble Space Telescope, which has revolutionized astronomy with its stunning pictures of the universe, has stopped working, engineers who work on the camera said yesterday.

The Advanced Camera for Surveys, a third-generation instrument installed by a space shuttle crew in 2002, went offline Monday, and engineers are still trying to figure out what happened and how to repair it.

``It's still offline today," Max Mutchler, an instruments specialist at the Space Telescope Science Institute in Baltimore, said yesterday.

Engineers are hopeful the problem can be fixed from the ground, said Ed Campion, a NASA spokesman at Goddard Space Flight Center outside Baltimore, which is responsible for managing the Hubble.

A bad transistor could be causing the trouble. If so, a backup could be used. Another suspicion is that some of the camera's memory was disturbed by a cosmic event. That could be fixed by reloading the memory.

The camera sent messages Monday indicating power supply voltages were above their upper limits and causing it to stop working.

The loss of the camera has not shut down the telescope entirely. Other instruments are running. Hubble, launched in April 1990, needs new batteries and gyroscopes if it is to keep working beyond next year.