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, March 29, 2017
Today's Astronomy Picture of the Day shows the use of lasers for image-sharpening. Anybody remember Pink Floyd under a planetarium dome with lasers?