Dawn to Ceres: Processors for the Protoplanet

Dawn’s mission: Ceres

Dawn was launched in 2007 by NASA/JPL and was built by Orbital Sciences becoming their first interplanetary spacecraft.  Dawns mission was to visit the two largest dwarf planets in the Asteroid belt, Vesta and Ceres.  After visiting Vesta for over a year in 2011-2012 Dawn used its ion engines to break orbit, and travel to Ceres, a journey of 2.5 years.

In the next few hours Dawn will be captured by Ceres gravity and begin orbiting it.  These protoplanets, are very interesting scientifically as they provide a look into our solar systems past.  Dawn will orbit Ceres for several years and perhaps discover what the mysterious bright spots are, among other things.  Studying a planet, even a dwarf planet, requires processing power, and for that Dawn is well equipped.

Dawn is solar powered, so power budgets are of great concern.  At 3AU (three times further from the sun then Earth) Dawns solar panels are rates at about 1300 Watts.  This has to run all the science experiments, the main computers, the comms, and most importantly the electric ion engine, which uses electricity generated from the panels to excite and eject Xenon gas at very high velocities.  Thus, power consumption is more important then raw processor power here, especially for the systems that are on most of the time.

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