These great hollow globes of artificial super-metals, and artificial transparent adamant, ranged in size from the earliest and smallest structures, which were no bigger than a very small asteroid, to spheres considerably larger than the Earth. (Olaf Stapledon, STAR MAKER)
Wednesday, September 17, 2014
Tightening the Belt
Today's Pluto Picture of the Day is an artist conception of the Kuiper Belt, ranging from 30 astronomical units (1 AU = the distance of the Earth's orbit from the Sun) out to 50 astronautical units in depth.