Number 36, November 2005


1)  The New FUSE Observatory:  Open for Business
2)  New Data Sets Publically Available

1)  The New FUSE Observatory:  Open for Business

	After months of development and testing of operations with a single 
reaction wheel in the control loop, the New FUSE Observatory is coming online!  
In early November, the Observatory was declared "green" and we are now giving 
new science observations priority over continued development, which will 
continue in the background.  See the latest FUSE Mission Status Report for 
more information:

	The FUSE Project, with the unanimous support of our users committee, is 
referring to FUSE as a "new" observatory because its modes of operation and 
observing capabilities and constraints are sufficiently different from those 
prior to the Dec. 2004 wheel failure, even though the scientific instrument's 
performance is the same as before.   The capabilities of the New FUSE are being 
applied to the Cycle 7 proposal review scheduled for next week.

2)  New Data Sets Publically Available

	The New FUSE Observatory largely manages the momentum of the remaining 
reaction wheel by pointing alternately in directions that spin the wheel up or 
down as needed to keep its rate of spin in the operational range.  As such, we 
need a high density of targets in the available part of the sky in order to 
perform efficient operations.  Since the Cycle 7 selections are still in 
progress, the FUSE Project Scientist has approved plans to address a near-term 
target shortage in two ways.  He has given permission to schedule additional 
observations of previous FUSE targets that are in available regions of the sky, 
and he has allowed the expansion of the "sky backgrounds" program to 
accommodate operations with the New FUSE.

	Observations of previous targets will all be scheduled under program 
IDs that begin with the letter "U". Programs U101, U102,  U103, and U104 
include approximately 300 previously observed FUSE targets above 50 degrees 
declination (north), and programs U106, U107, U108 and U109 contain 
approximately 300 targets below -50 degrees declination (south). No Magellanic 
Cloud targets are included in these programs as there are plenty of requested 
new observations in those regions.  Targets with nominal fluxes approaching the 
FUSE brightness limit have also been removed.  All U program observations are 
"plain vanilla" LWRS observations benchmarked for 8 ks.  Actual observation 
times will scale upward and downward from this value  as needed for efficient 
operations.  We have just begun observing U program targets in early November.

	The FUSE project instituted a "Sky Backgrounds" program early in the 
mission to use time during thermalization periods that would otherwise go 
unused.  These data were collected under program IDs S405 and S505. Since the 
reaction wheel failure in December 2004, we have expanded this concept to 
include additional pre-selected and randomly selected sky background pointings. 
The new program IDs S605 (north circumpolar grid) and S705 (south circumpolar 
grid) contain pre-defined circles of sky background positions at +/-60, 65, and 
70 degrees on 5 degree centers.  Programs S805 and S905 will be used for random 
positions defined by FUSE MP to assist in momentum management.  As with the 
earlier background programs, the data can have significant integration times 
and/or can build up significant integration time for those positions that are 
reobserved multiple times. In certain cases, total integrations of many 10's of 
ks are built up at a given position.  They have (and we trust they will in the 
future) provided interesting detections and constraints on faint O VI 1032 
emission at locations across the celestial sphere.  Using MAST to search for 
publications by program ID, for example reveals a number of references relating 
to the background program S405.

	Targets for these programs are available for scheduling at low priority,
and are used to help manage momentum or fill in schedule gaps only when a 
peer-reviewed target is not available in the stable region of sky.   All U and 
S program data will be archived and will go public immediately.  It is left to 
the user community to periodically visit the archive and see what has been 
observed in these programs and determine their interest. We hope that this 
creative use of the FUSE resource will pay unexpected dividends to the FUSE 
user community.  Users can reach the FUSE archive at the following URL:

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 the 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 Program Manager at JHU is Mr. Randy Ewing, and the NASA Project Scientist for FUSE is Dr. George Sonneborn.

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