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IPhone on space.

  1. Jun 14, 2011 #1
    So it seems the iPhone won the race to space. Anyways, it says that it will look for radiation effects with "single bit upsets", is memory really that sensible to radiation?
     
  2. jcsd
  3. Jun 14, 2011 #2
  4. Jun 14, 2011 #3

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    Staff: Mentor

    Absolutely, and the problem is in general getting worse as die sizes decrease. All but the very cheapest of satellites are now designed to have multiple avionics systems running in parallel. They vote on the incoming sensor data, vote on the outgoing commands, sometimes even on memory content. A computer that repeatedly steps out of line is voted off the island. This redundancy is danged expensive. It's there for a reason.

    A somewhat recent example of an SEU causing a real problem: http://www.jpl.nasa.gov/news/news.cfm?release=2010-151. The Voyager spacecraft are particularly sensitive to SEUs because they are now running in single string mode (only one active set of avionics) to conserve power.
     
  5. Jul 3, 2011 #4
    Old memory like ferite core are not, but those are massive (huge boards with a few hundred bytes) and slow. Modern memory is small and fast because it's solid state. Solid state devices are susceptible to radiation.

    Thanks for the comments and questions. I wrote SpaceLab for iOS.
     
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