FUSE Mission Status Report

Mission Status Report #39      Star Date: December 5, 2000

FUSE Completes First Year of Science Operations!

Caption: A whole YEAR of FUSE Science Observations on one plot! OK, I realize you can't read it, so click on the graphic above for a bigger version that is ALMOST legible (36 Kb jpeg)! Or, for a bigger version you can scroll around in and actually read, CLICK HERE! (But beware: 1.4 Mb jpeg!)

[Plot courtesy of FUSE mission planner Bryce Roberts.]

The graphic shows one month per horizontal line (starting with December 1999), and each line is blocked out into separate observations or activities. Even at the scale given above, you can see some interesting features, like the very busy set of observations done through the late September-early October period (when we were observing in the Magellanic Clouds), followed by some very long pointings of a faint quasar. Observations labelled with "Pxxx" are observations made for the Principal Investigator team, while those starting with "A" are are for Cycle 1 Guest Investigators. "M" programs are for calibration and alignment activities, and "Q" programs are for our French collaborators on the PI team.

(Click image above to see larger version.)


Hello World,

All continues to go extremely well on the FUSE project, with the satellite hardware behaving nominally, and ground operations at JHU going smoothly.

December 1 marked the first anniversary of official FUSE Science Operations, what we nominally called "Cycle 1." With a few days to reflect, I can summarize the results in some numbers:

  • Just over 10 million seconds of total on target exposure time, including calibration and test programs!
  • 8.9 million seconds of "science" exposure time! (This is actual observing time on science targets and does not include acquisition times or other pads.)
  • Our average science efficiency over the first year of operations was 27.2%. (Again, this is on-target science time as a percentage of wall clock time. This may sound low, but in actuality it is very good for a mission in low earth orbit, where the earth blocks our view about 60% of the time, and where time for moving between targets and performing other tasks like tests and calibration activities take time as well! This is a bit better than we expected for this first year, and we are continuing to make improvements in this area.)
  • About 1150 separate observations or activities were scheduled for the spacecraft, with pointings accomplished on over 680 unique objects in the sky!
  • Overall percentages for time usage included 61.9% PI team science time, 25.7% Guest Investigator science time, and 12.4% for all calibration and engineering-related activities.
  • About 75% of proposed Cycle 1 Guest Investigator observations were accomplished in the first year. (But Cycle 1 was intentionally over-subscribed, and many of the remaining observations are on objects with constrained visibility or for which other factors limit when the observations can be scheduled. These observations are still in the planning system and will be scheduled during the second cycle of observations, as they become available.)

As is often the case, however, the numbers don't tell the whole story. The numbers don't show the weekends worked, the midnight calls to fix some problem, or the incredible effort put forth by an extremely committed and dedicated team of scientists, engineers, and support staff to build, calibrate, and operate this satellite observatory. It is with great pride and admiration that I tip my hat to these folks, with a hearty "Congratulations!" for a job well done.

On to Cycle 2!

Reported by: Bill Blair, Chief of Observatory Operations

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