Free Astronomy Magazine September-October 2019

24 SMALL BODIES Every day, over 100 tons of dust and particles of interplanetary sand fall to Earth. At least once a year, a meteoroid as big as a car hits the atmosphere, generates an impressive fireball, and disintegrates before reaching the surface. Every several hundred years, a small asteroid as big as a football field impacts our planet and causes significant damage to an area of thousands of square kilometers, as happened in the Tun- guska event. When will the next impact occur? The Tunguska event, now rarer than expected SEPTEMBER-OCTOBER 2019 by Michele Ferrara revised by Damian G. Allis NASA Solar System Ambassador