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, May 6, 2019
Today's Astronomy Picture of the Day is a short video depicting a flyby of Messier 51, The Whirlpool Galaxy. Imagine being able to do this for real!