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, February 10, 2017
Deep in the Heart Nebula (IC 1805) stands a tower of gas. Today's Astronomy Picture of the Day peers inside the cluster Melotte 15 to tease out the details.