Voyager I is back from the dead

Since it began sending back unintelligable data late last year, Voyager 1 has been presumed dead, reduced to tinfoil and a radar dish floating through interstellar space.

Until this week. On Monday, JPL announced that Voyager I was back from the dead! The culprit? A broken memory chip in the flight computer. So, the team tried placing the affected code somewhere else in the main memory of Voyager I.

However, no space within the memory was large enough to store all that code! So, what was there to do? The team cut the code up into snippets, and placed them into different spots in the memory. This came with the hassle of rewriting the code to deal with all references to it in other software snippets.

This might sound easy with modern programming languages, but remember: Voyager 1 launched in 1977. Its memory probably is measured in kilobytes instead of gigabytes, and it's also written in assembly! For those of you who are unversed in programming, assembly is a language with only 2 operations: Write A to a place in the memory, and delete A from that place. Nevermind that, just dealing with the 1.5 * 10^8 milliseconds of ping that it takes to transmit signals to and from Voyager 1 is enough to make all but the most seasoned of programmers tear their hair out in frustration.

"During the coming weeks, the team will relocate and adjust the other affected portions of the FDS software. These include the portions that will start returning science data," NASA said in a press release.

The Voyager probes were launched in 1977 due to a rare alignment of the Solar System's outer planets. Voyager 1 was slingshotted right out of the Solar System and into interstellar space, while Voyager 2 was sent on a more leisurely route around Jupiter, Saturn, Uranus and Neptune. Together, these probes are still up and running, although NASA is planning to slowly shut down their systems by next year.