About
What does the title of this blog mean? What is II-I- and what does it stand for?
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| The Pioneer Plaque: our message to the stars (from Wikimedia commons, originally designed by Carl Sagan and Frank Drake. Photograph by NASA Ames Research Centre). |
In 1972 and 73 NASA launched the Pioneer 10 and 11 spacecraft on to their journey into interstellar space. On board those spacecraft was a plaque designed by Carl Sagan and Frank Drake, now known as the Pioneer Plaque, upon which a number of pictorial messages and symbols regarding the nature of Earth and humans were etched. They were put there to serve as a label of ownership, a message to the stars and a guide to our species and home planet, in the hope that if these craft where ever recovered far in the future by an intelligent extraterrestrial civilisation, they would be able to decipher some of the mysteries surrounding the probes and their origins using the guidance that the plaque provides.
It outlines the size and shape of humans against the silhouette of the spacecraft and includes the symbol for the hyperfine transition of neutral hydrogen to act as a unit of time and length, as well as a map showing the relative position of the solar system in regards to the centre of the Milky Way Galaxy. Most poignantly however, it also includes a depiction of the solar system and the relative orbits of the planets using binary code and the orbit of Mercury for reference. In this system, the Mercury is denoted as I-I-, Venus is I–II and Earth is forever immortalised as II-I-.
I could think of no more appropriate name for this humble blog than the label for our planet, our home, that is currently attached to one of the most distant man-made objects in existence, and that may one day provide another intelligent species with some insight into our fleeting existence in this quiet corner of the universe.
About Me
I’m a PhD student at the University of East Anglia. My research focusses on the geochemical cycles of extrasolar planets and their parallels to the early Earth system. Also interested in astrobiology, planetary science, geography and evolution. My profile at Journalisted.
Contact
Would you like to contact the author of the this blog, or become one yourself? Please email: andrew.j.rushby [at] gmail.com or tweet me @andrewrushby.

Ha, very witty. And for the record, I got it.
Interesting and nicely done!
After reading about 3 more of your posts–I can see why you are in demand! Great–and rather creative, as well!
Very kind, thank you.
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