Once In All of Human History

On July 19th, for the first time in human history, Earth was photographed by two of our satellites; Cassini, in orbit around Saturn, and Messenger, orbiting Mercury.  From Saturn, we see a single dot, easily confused for any of the other lit dots in the sky, except being a bit brighter.  In the Mercury Messenger image, we see our earth-moon system as a dual planetary system.  With our outsized moon, many astronomers view us that way. 

Look well at that little spot - the bigger of the pair of dots.  Every person in your family, or my family; every person, great or small, known to history or lost to time, has lived on that dot.  Every single thought, word, or deed our species knows of took place on that little dot.  No human being has ever ventured beyond the second smaller dot in the right image.  Space-faring?  We have barely gotten off the porch.  

Click to embiggenate.  Or go here to get other sizes.