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)
Friday, April 22, 2016
Today's Astronomy Picture of the Day shows NGC 7635, a planetary nebula in the constellation of Cassiopeia. A wonderful Hubble Space Telescope image!