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, May 6, 2016
Eye of Cepheus
Today's Astronomy Picture of the Day shows the Iris Nebula in the constellation of Cepheus. The size of five full moons! Imagine if it were bright enough to be observed like this with the "naked" eye.