FUSE News
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/Marseilles
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/
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.