Asteroid that missed the Earth by inches last night was so big it had a moon

USA: The asteroid which buzzed Earth last night was so massive it had its own moon. Stargazers around the world trained their telescopes and binoculars on asteroid 2004 BL86 and noticed a tiny baby moon orbiting it. 

This cute moon was just 70 metres wide meaning that Usain Bolt could gallop around it in just under seven seconds, although low gravity would make it almost impossible for the world's fastest man to stick to the surface. Its mum, a massive space rock, was a third of a mile wide and zoomed past Earth at a distance of 745,000 miles. 

If you consider the Earth is just under 8,000 miles wide and the moon is about 240,000 miles away, you will appreciate just how close this asteroid came to planet earth. A rock of similar size was responsible for killing the dinosaurs after hitting Mexico's Yucatan peninsula some 65 million years ago.

Or so we hope. NASA is currently tracking more than 11,000 asteroids - but admitted it has only found 98% of the most dangerous ones. This could mean that more than 200 asteroids could be on a collision course with earth. If the dinos didn't survive an impact, we probably won't either.
Read more at: http://www.standardmedia.co.ke/lifestyle/article/2000149434/asteroid-that-missed-the-earth-by-inches-last-night-was-so-big-it-had-a-moon

Or so we hope. 

NASA is currently tracking more than 11,000 asteroids - but admitted it has only found 98% of the most dangerous ones. This could mean that more than 200 asteroids could be on a collision course with earth. If the dinos didn't survive an impact, we probably won't either.