Watching killer asteroids (Introduction)
And a large meteorite hits Russia yesterday:-http://www.newscientist.com/article/dn23178-russian-meteor-will-teach-us-about-future-bigger-hits.html-http://phys.org/news/2013-02-meteor-shower-panic-central-russia.html-And a huge asteroid hit about 350 mya in Australia:-http://phys.org/news/2013-02-world-largest-asteroid-impact-zone.html