NASA Finds Cause of Voyager 2 Glitch

astroengine writes "Earlier this month, engineers suspended Voyager 2's science measurements because of an unexpected problem in its communications stream. A glitch in the flight data system, which formats information for radioing to Earth, was believed to be the problem. Now NASA has found the cause of the issue: it was a single memory bit that had erroneously flipped from a 0 to a 1. The cause of the error is yet to be understood, but NASA plans to reset Voyager's memory tomorrow, clearing the error."

Comments

Re:Really?

[rew]

Certainty? I don't think so.

I think they simulated Voyager with this bit flipped and saw the same output (that is transmitted to earth).

I hope they tried to flip ALL bits, and found that only this one bit would give the results seen. If you would follow the code and find and test just a few likely places, I'd expect a few more unexpected places to give the same results.

The quick fix is to send the correct byte to the craft and hope that fixes it. If the bit has become stuck in the new position, they will have to do a remote firmware upgrade (with the code rewritten to fit the stuck-at value...) Other memory cells may have broken down in the mean time, but with a stuck-at value that is correct for the current version of the firmware, which you won't know until you try them....

Re:Just incredible!

[commodore64_love]

>>>have their infinitely "more powerful" laptop process 5% of the NYSE volume like our mainframes did, while supporting about 100K trader desks, a couple TB of tape robot storage, etc.

A laptop could do that if it had an efficient assembly-written OS (like Kolibri), rather than the bloated general purpose OSes like Windows NT or OS X. At my former company we used the equivalent of laptops (Pentium 2s) to manage, load mission data, and launch a ship full of Tomahawk missiles.