Happy Birthday Stardust! FROM STARDUST PROJECT Posted: Feb. 22, 2000
There have been "storms" to sail through. The first attempt to move from gyro-stabilized control of the celestial attitude to pure star-referencing, found a software "bug" that caused the spacecraft to invoke its automatic fault protection. This placed Stardust in a "safe" mode to allow the controllers to troubleshoot and fix the problem. When the ship invokes the safing routine, it shuts down all unnecessary activities, including its telecommunication with Earth, and turns to the sun to ensure the lifeblood of solar energy floods its batteries and electronics with electricity. When it deems all is well, it sets up a plan to contact us on Earth, tell us what happened, and let us tell it what to do next. This routine, while carefully designed to protect the spacecraft, is still an "anxiety event" for the crew back on Earth. It's a bit like the feeling when your teenager is late coming home, and you get no phone call. The anxiety builds fear until the dutiful signal comes through. "I'm here!" "I'm O.K.!" Stardust and its crew have navigated three more safing events, all involving data handling by on-board software.
During this first year in space, Stardust has operated the Cometary and Interstellar Dust Analyzer (CIDA) and the Dust Flux Monitoring Instrument (DFMI). Both have worked well, but DFMI has a power supply with an oscillation. That means the crew has had to develop a way of compensating for this. Currently, the plan involves limiting its operating time and cycling it off and on. Testing of this technique will come late in the year. DFMI is currently "off." CIDA has collected data of some interest to the science team. Analysis is underway to determine if interstellar dust impacts occurred as the ship navigated "upwind" in the interstellar dust stream. With Stardust rounding the "mark" to sail back downwind toward Earth, the science team has turned the CIDA off. As Stardust turned toward home, the crew commanded Stardust to fire on-board rockets to achieve the precise course for the Earth-swingby next January. The ship performed flawlessly in completing the three required rocket burns. In addition, the sample-return capsule (SRC) housing the Aerogel collector has been unlatched. This is in preparation for deployment of the collector in late February. Deployment will mark the beginning of the attempt to "catch" interstellar particles to bring home. So, the adventure continues. It is bittersweet in that while Stardust sails on, its sister ships at Mars were lost. The trauma underscores the risks of voyaging into the unknown, attempting audaciously to know it. To know the unknown most often requires the birth pangs of failure. Earth's oceans are littered with the bones of the ships and sailors who brought us to the understanding of our planet we now enjoy. We sail its sky with the safety provided by the sacrifices of the Wrights, Lindberg, Doolittle, Yeager, Earhart, and many others. And we plunge into deep space on the shoulders of Newton, Kepler, Tsiolkovsky, Goddard, and Von Braun, with the physics of space and the fire of rockets.
I celebrate the spacecraft. I congratulate the crew. Sail on, Stardust! May the "wind" be at your back! Happy birthday! Dr. Kenneth L. Atkins |
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