Published February 16, 2013, 12:00 AM
Astro Bob: 50-foot space rock hits Earth every 50-60 years
Cosmic debris rains down through the atmosphere nearly every day, accumulating at a rate of 37,000 to 78,000 tons per year. While that may sound like a lot, much of it is dust or passes unseen over the oceans.By: Bob King, Duluth News Tribune
