Mission Status Report #87 Star Date: June 10, 2005
Caption: The FUSE satellite is seen superimposed on an ultraviolet image of the nearby galaxy M31, the Andromeda galaxy. The clumps of bluish-white are giant clusters of newly forming stars, regions of intense interest to astronomers and ideally suited to FUSE observations. (Graphic courtesy of FUSE project, JHU.)
The FUSE satellite has made steady progress toward the return to science operations over the last few weeks, after the hiatus caused by a reaction wheel failure in December 2004. (See Status Report #83.)
Since the last report, there have been several significant events in the recovery effort. Firstly, the repaired control system that works properly with less than a full complement of gyroscopes has been uplinked and tested, demonstrating that FUSE can operate in fine pointing mode and perform science observations again. The previous FUSE control system (prior to December) already worked properly with less than three gyros, but the new mode of operating with a single reaction wheel required some modifications. This is now done.
Other important developments have been on the ground support side of the project. With insights from the three-week period of test operations in late March and early April, we have been developing software tools that will be needed in the new mode of FUSE operations. These tools calculate stable regions on the sky where FUSE can point as a function of time. Selecting targets in these regions will be half the battle when we get back into science operations mode, and having efficient and accurate predictive tools will be very important. While the current tools are preliminary, they are good enough that we can use them for planning tests on orbit, which will be used to improve and/or validate these tools for use downstream.
Continued thanks to all of the FUSE Sciences Operations team, including our partners on the Mission Operations Team from Honeywell Technology Solutions, Inc., and our colleagues at Orbital Sciences Corporation, for their tremendous effort so far, and for their ongoing efforts as we improve the new control system.
Reported by: Bill Blair, FUSE Chief of Observatory Operations
Last Update: June 10, 2005