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 t housands of square kilometers, as happened in the Tun-
guska event. When will the next impact occur?
The Tunguska
event, now rarer
than expected
The Tunguska
event, now rarer
than expected
by Michele Ferrara
revised by Damian G. Allis
NASA Solar System Ambassador
Tunguska 111 EN_l'Astrofilo 29/08/2019 15:43 Page 24