FUSE News

Status Message, January 28, 2002

Dear Colleagues,

On Thursday January 24, the mission operations team uploaded new flight software constructed by Orbital Sciences Corporation. This software provides control about three othogonal axes using the roll wheel, the skew wheel and magnetic torquer bars. The satellite is now in the fine pointing mode. Our first data, for a star near the orbit pole, shows sub-arcsecond jitter. The first spectrum was obtained Friday night and a quick look at the LiF1 channel data shows no obvious signs of photometric degradation.

The satellite has been operating autonomously since Friday evening. We are operating near the north pole of the orbit, but plan to extend the region of operation down to 30 degrees from the pole over the month of February. As the orbit is tilted at 25 degrees and precesses with a 60 day period, we expect to be able to access targets with declinations greater than +35 degrees or less than -35 degrees when we return to science operations March 1. More than two-thirds of the FUSE observing programs have accessible targets. Over the following months, we plan to extend the satellite capabilities and sky coverage.

The above paragraph is based on modeling and our first test results. In late February, after we have done a more thorough evaluation, we will write to you with a more detailed description of the satellite's near term capabilities.

We close with a word of praise for the Orbital team and the operations team at JHU. It is their ingenious ideas and long hours over the last seven weeks that have made this prompt recovery possible.

Warren Moos and George Sonneborn


The FUSE Project is managed by Johns Hopkins University's Center for Astrophysical Sciences in Baltimore, MD, for NASA's Goddard Space Flight Center. The FUSE Principal Investigator is Dr. Warren Moos, the FUSE Project Manager at JHU is Mr. J.B. Joyce, and the NASA Project Scientist for FUSE is Dr. George Sonneborn.