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, October 2, 2017
Today's Astronomy Picture of the Day shows two comets moving "together" in the sky. "Mouseover" the image in the link to get a constellation guide.