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'
Mars Had Surprising 400-Million-Year Lull Between Giant-Impact Eras http://www.space.com/36607-mars-giant-impact-lull-late-heavy-bombardment.html?utm_campaign=crowdfire&utm_content=crowdfire&utm_medium=social&utm_source=pinterest
Leading theory for how the solar system formed just disproved! “These small probabilities raise the prospect that the giant planet instability occurred before the terrestrial planets had formed. This scenario implies that the giant planet instability is not the source of the Late Heavy Bombardment and that terrestrial planet formation finished with the giant planets in their modern configuration.” In 2005, scientists put forth the Nice Model to explain the configuration of the Solar System’s…
The Hadean, being an informal not stratigraphically defined eon, is here defined as the period from the Tellus (proto-Earth)-Theia impact (circa 4520 mya) to the end of the LHB (Late Heavy Bombardment) period,about 3800 bya. Recently, Goldblatt et al. 2010 have proposed an even earlier eon, the Chaotian,for events pertaining to the formation of the Solar System