There’s no danger of a collision, but the space rock is large (4.4 km across) and it will be visible in small amateur telescopes during the nights around closest approach. Michael Jäger photographed the approaching asteroid from his private observatory in Weißenkirchen, Austria, on Aug. 29th

“What a fast mover,” says Jäger. “Minor planet Florence is now near Earth and shining like a star of magnitude +8 to +9.”
Named in honor of Florence Nightingale (1820-1910), “this is the largest asteroid to pass by our planet this close since the NASA program to detect and track near-Earth asteroids began,” says Paul Chodas, manager of NASA’s Center for Near-Earth Object Studies at JPL. Radar imaging is planned at NASA’s Goldstone Solar System Radar in California and at the National Science Foundation’s Arecibo Observatory in Puerto Rico. The resulting radar images could reveal surface details as small as 10 meters.

Source: Spaceweather.com