Late Heavy Bombardment - 'The Late Heavy Bombardment (commonly referred to as the lunar cataclysm, or LHB) is a hypothetical event around 4.1 to 3.8 billion years ago. During this event an extraordinary number of the impact craters on the Moon would have formed, and by inference an extraordinary large number of impacts on Earth... Extrapolating lunar cratering rates to Earth: 22,000 craters with diameters >20 km, about 40 > 1,000 km, several > 5,000 km'
Late Heavy Bomardment. Migration of giant gas planets such as Jupiter created the biggest meteor storm in our solar system's history, according to a new study. The research in the journal 'Nature Geoscience' paints the clearest picture yet of the causes of the Late Heavy Bombardment, a cosmic tempest 3.9 billion years ago, which shaped the solar system we have today.