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)
Monday, June 23, 2014
Today's Astronomy Picture of the Day shows ground-based laser defense systems in action. What? What's that? Oh, never mind. Just some astronomical lasers checking the quality of "seeing".