Every day, Earth is hit by 60 to 300 metric tons of space dust and smaller meteoroids. But sometimes, larger and more dangerous space rocks plummet to Earth, such as on June 30, 1908 when an estimated 40 meter-wide meteoroid exploded over the Tunguska, Siberia region in Russia, devastating 2000 sq. kilometers (770 square miles) … Continue reading "Watch Live 24-Hour Webcast for International Asteroid Day"