Mission Status Report #16 Star Date: August 30, 1999 NOTE: Mission Status Reports on the web page will continue roughly once a week, as events unfold.
Two views of the FUSE ground station in Puerto Rico. (Click either image to see larger version.)
High Voltage Up on Both Detectors!FUSE In-Orbit Checkout continued this week, with the high point being that we now have the high voltage ramped up on both Detector 1 and Detector 2 in the spectrograph. Both detectors are behaving normally, and the on-board logic is controlling the ramping up and down of the voltage as the spacecraft passes into and out of the high particle background "South Atlantic Anomaly" (SAA) parts of our orbit. Tests are in progress now to characterize the background levels and verify health and safety of the detectors. This is very good news indeed! Recall that each of the two detectors "sees" two of our four mirrors. Now that both detectors are up and running, we can begin with the crucial (but time-consuming) task of getting all four mirrors focused and aligned relative to each other and to the spectrograph apertures. Although other tests will be done in the same timeframe, focus and alignment will require most of our attention over the next several weeks. The last week has also seen a continuation of the problem described in last week's report with our UPRM ground station antenna (see photos above), which is our primary means of communicating with FUSE. The power outage that caused the initial problem must have damaged some piece of hardware, but the problems have been intermittant, making it very difficult to diagnose and fix. (If vou've ever had an intermittant problem with your car, you KNOW how annoying this can be! Now imagine your car is in Puerto Rico and you are working remotely from Baltimore!) Work continues by AlliedSignal technicians and by our own control center personnel to diagnose this problem and get it behind us. (And keep those hurricanes away from Puerto Rico while you're at it!) Excitement is building here on the team because, while we don't know exactly when, ONE OF THESE DAYS we are going to get starlight down all four channels and see what this baby can do! It's been a long time coming, but there is light at the end of the IOC tunnel. Reported by: Bill Blair, Chief of Mission Planning
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