The Tunguska explosion could have been caused by an asteroid that still orbits the sun

On a cool summer morning in 1908, a fireball appeared over northern Siberia. Eyewitnesses described a column of blue light that moved across the sky, followed by a tremendous explosion that leveled trees across more than 2,000 square kilometers. The explosion is consistent with a large meteor strike, but to this day, no evidence of a crater has been found. Now known as the Tunguska event, its cause remains a mystery to this day.