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No, not a CA (Cellular Automata). Instead, this is actually the Hadamard code matrix which was embedded on the NASA Mariner 9 spacecraft, launch in 1971. Mariner 9 was a NASA space orbiter that helped in the exploration of planet Mars. It was launched toward  planet Mars on May 30, 1971 from Cape Canaveral Air Force Station and reached the planet on November 13 of the same year, becoming the first spacecraft to orbit another planet — only narrowly beating Soviet Mars 2 and Mars 3, which both arrived within a month. After months of dust-storms it managed to send back the first clear pictures of the surface (for more do check on the Mariner 9 Wikipedia entry).

Hadamard codes (named after Jacques Hadamard) are algorithmic systems used for signal error detection, fault detection and correction, probably one of the first of their kind to follow the idea of an machine Artificial Intelligent self-regulation. Hadamard codes are in fact, just a special case of the more universal ReedMuller codes (here for an intro). In particular, the first order Reed–Muller codes are equivalent to Hadamard codes. Positively, without them, it would be impossible back then for Mariner 9 to arrive Mars taking stunning images like the one below (one of the first, Human eyes ever seen). Beyond the geniality of the Hadamard code as  a primeval approximation for machine self-regulation (details onto which are important for my own work), along with it’s practical utility on different fields of our current daily life, among so many other things, what strikes me, is that the Hadamard code picture above – in some instances – resembles itself one of the first photos from the red planet ever taken…


Image – Mariner 9 view of the Noctis Labyrinthus “labyrinth” at the western end of Valles Marineris on Mars. Linear graben, grooves, and crater chains dominate this region, along with a number of flat-topped mesas. The image is roughly 400 km across, centered at 6 S, 105 W, at the edge of the Tharsis bulge. North is up. (from Wikipedia)

p.s. – (disclaimer) I did play a lot over the title on this present blog post. From Hadamard, to Hada-mars, into Ada, you know, Ada Lovelace, Augusta, that terrific lovely English girl born in the 1800’s. Not my fault. In fact, they were all there onto the same space-time voyage.

[...] People should learn how to play Lego with their minds. Concepts are building bricks [...] V. Ramos, 2002.

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