Space.com Asteroid 2017 BX ‘Rerun’ – Earth Fly-By Explained by Astronomer | Video 25 January 2017 fborgosano Leave a comment Share: The space rock will fly within 162,252 miles (261,119 km) of Earth on Jan. 25, 2017. It is estimated to be about 30 feet in diameter. Slooh.com astronomer Eric Edelman explains. from Space.com bit.ly/2jZokUj Share: