There’s a rare chance to spot a huge asteroid whizz past the Earth tomorrow on its closest encounter since 1890. Asteroid Florence is the fourth largest near-Earth asteroid (NEA) and should be visible to amateur and professional astronomers alike for the next six or seven nights, flying closest to us at a distance of about 4.4 million miles on September 1. "Florence is the largest asteroid to pass by our planet this close since the NASA program to detect and track near-Earth asteroids began." Florence spins once every 2.36 hours during which time its brightness varies by 0.2 magnitudes. “One of our principal objectives is to obtain radar images that can be inverted to estimate the 3D shape and dimensions of this asteroid,” researchers said.

Source: Forbes August 31, 2017 10:07 UTC