Number 19 March 2002


1) FUSE Science Operations have Resumed
2) Target changes for accepted, low Declination, programs
3) Observatory Programs (Supplementary Targets)
4) CalFUSE News 

1) FUSE Science Operations have Resumed

After the recent downtime due to reaction wheel failures, we are pleased to 
announce that FUSE is back in business!  In late January, new control software 
was uplinked that enabled three-axis control using two reaction wheels plus 
magnetic torquer bars. February was spent performing a combination of tests and 
science observations, and in March we have transitioned back into full time 
science mode, with occasional tests still needed to enhance our capabilities 

Our primary limitation at the moment is sky coverage, with regions above
declination +40 (or below -40) degrees available for normal scheduling during
a 60-day precessional cycle.  We are hopeful that some capability to observe
lower declinations can be developed over the coming months, but development 
and testing of these techniques will take time.

We acknowledge the work of many people at JHU, NASA/GSFC, Orbital Sciences 
Corp., and Honeywell Technical Services, Inc., who have made the FUSE recovery
a reality.  It was a real team effort!

2) Target changes for accepted, low Declination, programs

        The FUSE satellite is back on-line and performing science observations 
after the recent downtime due to reaction wheel failures. The "new FUSE" 
maintains the same scientific capabilities as before in terms of sensitivity 
and spectral resolution. However, there are aspects of operations that have 
become much more complicated and in some aspects limiting. For all users with 
unobserved targets awaiting execution, we are requesting a reassessment of 
their target selection and that they consider modifications that may be in the 
best interest of both them and the project.

        Earlier this month, notifications and details of these target changes
were distributed by the Project Scientist (George Sonneborn) and the FUSE Chief 
of Observatory Operations (Bill Blair).  The text of these messages can be found

respectively.  Many observers have already responded, and the submitted target
changes are currently being evaluated.  We expect to notify the PIs and 
implement the accepted changes in early April.  While the deadline for the 
first go-around of target changes, including possible target allocation issues, 
has passed, we would like to emphasize that we will be accepting further target 
change requests on a continuing, case-by-case basis.  There will however be a 
hiatus on target changes once the cycle 4 NRA is released this summer.

3) Observatory Programs (Supplementary Targets). 

        To help maintain high scheduling efficiency of scientific observations, 
we have instituted a class of "Observatory Programs".  These programs are made 
up of targets at high declinations that are not currently allocated to any 
approved program, but which are of scientific interest.  The Observatory 
Programs will be used to fill any gaps in the observing schedule, but only when 
no regular approved target is available. These targets will have program 
ID Z9nn.  Any data obtained for these programs will have no proprietary period 
and will be placed in the public archive immediately after processing.
        To ensure a rapid turn-around, a first set of Observatory Programs 
have been defined and implemented by the FUSE User Support Group, with the 
approval by the NASA Project Scientist.  These first programs were selected to 
provide survey data complementing existing programs, or to provide flux 
measurements of target classes where such data are lacking.
        This first set of Observatory Programs consists of 6 programs with a 
total of about 250 objects.  The six programs are aimed at: 

1) FUSE Observations of stars in the NWU HST snapshot survey, 
2) A survey of Algol binaries, 
3) A survey of White Dwarfs from the McCook and Sion Sample.
4) A survey of O-B subdwarfs.
5) A complementary sample of LMC (ISM) sightlines
6) A survey of Herbig Ae/Be stars

The FUSE web site:

contains a list of the programs with some further description, as well as the 
rules applicable to these programs and targets.  We are finalizing a page 
on the JHU web site on which we will keep an updated list of the targets 
observed under these programs.  As these observations are released immediately 
upon satisfactory processing and quality control, we note that you can also 
keep abreast of these observations by regularly searching the MAST archives for 
program IDs Z9**. 

        A number of suggestions for further Observatory Programs have already 
been received from the community.  The originators of these programs should 
expect a letter from the NASA Project Scientist in the near future finalizing 
the constraints, requirements and agreements for possible selection.

        Suggestions for additional Observatory Programs are still being 
solicited. Suggestions of programs or targets to be added to this list should 
be sent to

4) CalFUSE News 

        We expect to release v2.1 of CalFUSE, the FUSE calibration pipeline, in
early April.  This version of the code features improved background calibration 
files and a new module that stretches the bad-pixel map to account for 
time-dependent changes in the Y scale of the detector.  A number of bug fixes 
(most are minor) developed over the past few months are also included.  For 
details, please see "Introduction to CalFUSE v2.1" at

In the near future, we will begin processing all new FUSE data with 
CalFUSE v2.1.  Once that is working, we will re-process the entire FUSE data set
with the new pipeline.  We expect to upgrade the entire FUSE archive at MAST 
with data processed with CalFUSE v2.1 by the end of the year.

The Observer's Electronic Newsletter is published by the FUSE project and is 
aimed at the FUSE user community.

Editor: B-G Andersson, FUSE Guest Investigator Officer.

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.

Further information about the FUSE Guest Investigator Program can  be
obtained from:  Dr. George Sonneborn;

Retour à la page d'accueil