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, February 3, 2014
NASA's Solar Dynamics Observatory (SDO) observes our dynamic (get it) Sun. Occasionally it also observes a transit or even an eclipse, such as this recent passage of our Moon.