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 5, 2014
Today's Astronomy Picture of the Day is a demonstration of gravitational lensing. A supercluster allows us to peek behind (and much further away!).