Voyager 2 Has Flipped Its Bit

May 12, 2010

I was just alerted to this story by one of the followers of this blog…  Last month Voyager 2 began returning some unusual signals.  This story is being reported by alternate news outlets as suggesting that aliens have tampered with Voyager 2.  NASA’s own take on the story is quite a bit more conventional.

I’m afraid most of my readers will be disappointed, but I feel confident a conventional explanation is the correct one.  I’ve seen something similar happen before.

As I detailed in Curiosity of Spirit, cosmic rays can have peculiar and devastating effects on electronic hardware. In most cases, like that of Spirit, a computer’s memory can be altered, perhaps even regions of it made unusable.  I remember a meeting I was pulled into at GRC in 1992 or 1993.  A recently launched military spy satellite had suddenly become effectively unresponsive.  It continued to transmit, but its responses were unintelligible, and it didn’t appear to be receiving or reacting to messages transmitted to it.  Ordinarily NASA wouldn’t be involved since it was a military project, but other agencies were apparently being cursorily queried for ideas as the satellite was soon going to miss a burn without which it might pose a risk to other satellites.

We were being asked to spend two hours brainstorming and come up with whatever we could.  Like Voyager 2 the basic protocol was still received as expected, but the contents were no longer readable. Initial theories related to a problem with the memory used to buffer the transmissions, problems with the logic boards, problems with a recent software update, etc.  The engineer who shared the office next to mine suggested something that fit the facts perfectly. “What if the encryption key was somehow changed?” A discussion followed and by the end of the meeting this became the leading theory, that a cosmic ray or some other event had bit flipped one or more bits in the encryption key used to encrypt data for Earth and decrypt data from Earth.  With the key no longer matching the key on Earth, the satellite was effectively speaking a different and incomprehensible language.  Someone relayed our guess to whoever had asked us to be involved and about two weeks later we learned that this was in fact what happened.  Apparently it was no easy task figuring out what the key had now become.  NSA was drawn into it and put their considerable resources to bear in trying different alterations of the original key to make a new key which could decode the received data.  It took them most of those two weeks, a stable of computers, and billions of combinations tested, to find the new key (which was only a handful of bits away from the original).  Once they had the new key, all communication and control was restored.

I’m pretty confident that Voyager 2 is suffering from a similar bit flip problem.

John

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