Number 6 March 1999


Contents:


1) Mission Status
2) FUSE Observers Advisory Committee (FOAC)
3) Target Acquisitions for Visually Bright Sources
4) Updated Web-sites 


1) Mission Status

	FUSE satellite testing is proceeding very well.  The refurbished IRUs
were reinstalled on March 8 and have been extensively tested since then.  The
results are very encouraging.  In their refurbished state they now have a
predicted lifetime of 9 years.  We are on track for March 31 shipment to KSC
with a presently planned launch on May 20.

	The UPRM ground station is now enclosed in its protective radome and
certification testing is proceeding. Recent UPRM telemetry test operations
with the Sampex satellite and the FUSE Satellite Control Center (SCC) at JHU
were successful. Additional tests with UPRM, the DSN, Hawaii/USN and the Space
Network (TDRSS) are under way.


2) FUSE Observers Advisory Committee (FOAC) formed

	The FUSE Observers Advisory Committee (FOAC) was recently established 
by NASA to advise the FUSE Project Scientist and the FUSE Project at JHU on 
issues related to the use of FUSE by the astronomical community. FOAC members 
will generally serve for at least 1 year and are asked to attend up to two 
meetings per year. The membership of the first FOAC is given in the table 
below.  The first meeting of the FOAC will be held in late April 1999.

	We hope that the FOAC will also serve as an effective advocate for the 
GI community, and GIs with any FUSE-related concerns are encouraged to express 
those concerns to the members of the FOAC. 


       Name                           Institution 
   Joel Bregman                   Univ. of Michigan 
   Jean-Michel Deharveng        LAS/Marseille 
   Steven Federman                Univ. of Toledo 
   Edward Guinan                  Villanova Univ. 
   Graham Harper                  Univ. of Colorado 
   John Hutchings                 DAO/Canada 
   Anuradha Koratkar              STScI 
   John Raymond                   Center for Astrophysics 
   Peter Wannier                  JPL 


3) Target Acquisitions for Visually Bright Sources

	In preparing for the operational phase of the mission, we have 
identified a category of target for which special care needs to be taken in 
order for target acquisitions to be successful.  We alert users to this here 
in order to provide you with an opportunity to take corrective action if you 
suspect this situation applies to any of your targets.  You may be contacted 
by a FUSE Mission Planner if we feel there is a potential problem with your
submitted program.
 
	The sources of particular concern are those that are visually bright
(V<8) but faint enough in the FUV that a FUV Peak-up acquisition may not work.
Such targets cannot be centroided in the Fine Error Sensor camera (because 
they saturate), and thus any small coordinate differences are not removed.
We need to acquire such targets using "Guide Star acq." mode, for which
the target coordinates must be specified accurately IN THE HST-GSC FRAME OF 
REFERENCE.  You could supply the best absolute coordinate in the world, but 
if that coordinate is NOT in the GSC frame of reference we could fail the
target acquisition.  
 
	Currently, such a target cannot be planned for the HIRS aperture, and 
will only work well for MDRS if the coordinate is accurate to about 1 arcsec 
with respect to the GSC system.  The problem is complicated further because 
many such targets also have significant proper motions (for which users 
should have corrected their coordinates when necessary already, but which 
adds more uncertainty in target position).  For any such target that does 
not have a confirmed accurate RELATIVE coordinate to the guide stars, the 
user may want to consider using the LWRS aperture, or placing the target 
on HOLD until the coordinate situation can be analyzed further.  Refer to
the FUSE Observers Guide on-line for further information about target 
acquisition.

4) Updated Web-sites 

	As usual, we try to keep the FUSE web sites as up-to-date as 
possible.  You will in particular notice that the GSFC site has recently been 
significantly enhanced, with both new layout and additional content.  Go 
there for programmatic schedules, preliminary information about GI budgets etc.
Updates at the JHU site include a "FUSE Launch Status" page, which allows you 
to keep up-to-date on the latest developments in the launch campaign.
Suggestions for further additions or modifications are, as always, welcome.

http://fuse.pha.jhu.edu
http://fusewww.gsfc.nasa.gov/fuse/
 

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The Observer's Electronic Newsletter is published Monthly 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. Dennis McCarthy, 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; sonneborn@stars.gsfc.nasa.gov
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