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)
Tuesday, May 3, 2016
Today's Astronomy Picture of the Day shows auroral activity over Sweden. "Mouseover" the image to get a guide to the constellations visible in the image.