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)
Saturday, April 14, 2018
Flying Over Mars
Today's Astronomy Picture of the Day is the view from 250 kilometers up courtesy of the NASA's Mars Reconnaissance Orbiter. Shadows and peaks, seasonal frost and so much to explore.