Saturday 27 January 2007 at 13:34 CET, the NASA/ESA Hubble Space Telescope entered into a protective "safemode" condition most likely triggered by a short circuit in Hubble's main instrument the Advanced Camera for Surveys (ACS). (Image credit: Ball Aerospace & Technologies Corp)
Saturday 27 January 2007 at 13:34 CET, the NASA/ESA Hubble Space Telescope entered into a protective "safemode" condition most likely triggered by a short circuit in Hubble's main instrument the Advanced Camera for Surveys (ACS). ACS had, since June 2006, been running on its secondary backup electrical system.
An Anomaly Review Board has been appointed by NASA. It is being investigated whether ACS can be returned to using the primary electrical system enabling one of its parts, the Solar Blind Channel, to return to operation. The main part of ACS will most likely not be restored.
A fifth Hubble Servicing Mission (SM4) has been scheduled by NASA for "not earlier than May 2008". Options for repairing the ACS camera during this mission are being investigated.
In the meantime, Hubble will be returned to work again with the other available instruments onboard: the Near Infrared Camera and Multi-object Spectrometer (NICMOS), the Wide Field and Planetary Camera 2 (WFPC2) and the Fine Guidance Sensors (FGS'es).
A call to the astronomers using Hubble is being issued, urging them to re-plan their upcoming observing programmes to take the new situation into account. The deadline for these changed proposals for observing Cycle 16 is February 9, 2007. Out of 750 total proposals for Cycle 16, 500 were for ACS (2/3).
"ACS took over from WFPC2 as Hubble's 'workhorse' at the last Servicing Mission 3B in 2002. Although we are taking a step back, it is far from 'game over' for Hubble", says ESA's Hubble scientist Bob Fosbury.
Note: This article has been adapted from a news release issued by ESA/Hubble Space Telescope.
