SternisheFan sends news of researchers who encoded an MP3, a PDF, a JPG, and a TXT file into DNA, along with another file that explains the encoding. The researchers estimate the storage density of this technique at 2.2 petabytes per gram (abstract). "We knew we needed to make a code using only short strings of DNA, and to do it in such a way that creating a run of the same letter would be impossible. So we figured, let's break up the code into lots of overlapping fragments going in both directions, with indexing information showing where each fragment belongs in the overall code, and make a coding scheme that doesn't allow repeats. That way, you would have to have the same error on four different fragments for it to fail – and that would be very rare," said one of the study's authors. "We've created a code that's error tolerant using a molecular form we know will last in the right conditions for 10 000 years, or possibly longer," said another.