Natural History Wanderings

EarthSky reports

It’s several miles in diameter, biggest near-Earth object to pass so close in a century.

Asteroid 3122 Florence will safely pass by our planet on September 1, 2017 at over 18 times the Earth-moon distance. The asteroid will not be visible to the unaided eye. It will, however, become visible in small amateur telescopes by late August, in the course of what will become the closest encounter to Earth by this asteroid since 1890.

Read more at A really big asteroid is about to pass Earth | Astronomy Essentials | EarthSky