The POT He said the telescope went into hibernation more than a week ago when one of its three remaining gyroscopes, part of the guidance system, failed. The same device has been causing problems for months and has disrupted scientific operations.
Hubble remains safe but idle while flight controllers determine how to proceed, officials said. The space agency was scheduled to outline a path forward on Tuesday.
Hubble received six new gyroscopes during the astronauts' last visit in 2009. The devices' spinning wheels keep the telescope stable and oriented correctly by tracking Hubble's rotation and position in space.
Three gyroscopes no longer work. NASA said the 34-year-old observatory could continue making discoveries with just one or two good gyroscopes.
The space shuttle Discovery launched Hubble into orbit in 1990. Its larger and more powerful successor, the Webb Space Telescope, was launched in 2021.