Thanks, Rosetta with this one further hurrah. It might be grainy and fuzzy, but it is still an excellent photo.
Thankfully, Rosetta’s compression software didn’t pack the look pixel-by-pixel, rather encoding it layer-by-layer. This meant the image might be recompiled, however with a lot of the detail missing. With 1 / 2 of the information received, the scientists were handling a compression ratio of just one:38 when compared to expected 1:20. This meant the compression was lossy, although not catastrophically lossy. Consider an MP3 having a bit rate reduced lower to 96Kb/s rather of 320Kb/s sure it may sound super shitty, but you may still write out the background music. Within the situation from the Rosetta images, this “added” compression converted to some coherent — but fuzzy — picture.
On September 30, 2015, the Rosetta spacecraft gradually drifted towards the the surface of Comet 67P/Churyumov — Gerasimenko, ending a extremely effective 12-year mission. Scientists in the European Space Agency thought they’d retrieved all Rosetta’s photos, however a re-research into the spacecraft’s final transmission has revealed your final fuzzy photo taken only a couple of ft in the surface.
Rosetta’s final image was taken a distance between 17-20m, which matches a ten-square-feet (one-square-meter) region around the comet surface. That’s pretty close! At this distance, Rosetta’s camera could not really focus (it had not been created for that), therefore the final picture could have been fuzzy to start with.
This is what happened: a pc aboard Rosetta split images into telemetry packets just before transmission to Earth. Its final image was said to be split up into six discrete packets, each composed of approximately 23,048 bytes of information. ESA scientists had only received three from the six packets, which contained just slightly above 1 / 2 of the needed total.