Step #11 in the Human Conquest of Space

In my previous post I talked about the magical quality of an orbit: Each time a spacecraft settles into a permanent path around a new object, humanity has taken one more step in venturing off this little blue world of ours and becoming colonizers of the universe. When the Rosetta reached Comet Churyumov-Gerasimenko on August 6 it marked the 11th celestial body we've orbited: Step #11 in the human conquest of space. Going from zero to 11 has taken just under 57 years; the anniversary of Sp