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)
Thursday, April 20, 2017
Today's Astronomy Picture of the Day is a series of radar images of Asteroid 2014 JO24. A "Potentially Hazardous Asteroid", it's probably prudent to collect data on this whirling bullet.