Written to the chain on 07 Jan 2015, block 337,874.
The Arecibo message — the 1974 radio transmission beamed at globular cluster M13, describing human DNA, our solar system and the telescope that sent it — re-transmitted into Bitcoin in 2015. The upload includes both a coloured rendering and the original as ASCII ones and zeros. A message designed to outlast the civilisation that sent it, placed in a second medium built for the same purpose.
AtomSea and EMBII built a higher-level publishing system on top of fake-key-hash style storage. A top-level transaction acts like an index: it contains ordered transaction IDs, length markers, filenames, captions, and sometimes profile or signature metadata.
More about AtomSea-P2FKEvery byte shown here was read from these transactions. Open one in a block explorer to check it yourself.
