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)
Saturday, December 13, 2014
Today's Astronomy Picture of the Day shows Messier 31 in a combined image showing both the light frequencies we can see and cannot see. Ground-based and space-based equipment working together!