Late Heavy Bombardment: The Great Cataclysm

The Solar System's Violent Past

The Late Heavy Bombardment (LHB) was a period of intense bombardment in the inner solar system that occurred approximately 4 billion years ago.

This bombardment left a lasting mark on the surfaces of the terrestrial planets, including Earth, Mars, Mercury, and the Moon.

Scientists believe that the LHB was caused by a combination of factors, including interactions between Jupiter and Saturn, and the gravitational influence of a passing star.

The Evidence for the LHB

The evidence for the LHB comes from several sources, including:

• The heavily cratered surfaces of the terrestrial planets
• The petrology of lunar rocks
• The presence of impact melt sheets on the Moon and Mars
• The presence of isotopic anomalies in lunar rocks

The Effects of the LHB

The LHB had a profound impact on the evolution of the terrestrial planets.

It is thought to have been responsible for:

• The formation of the Moon
• The extinction of the early Earth's oceans
• The formation of the Earth's atmosphere
• The delivery of water and organic molecules to the Earth

The Implications of the LHB

The LHB is a reminder of the violent and chaotic early days of the solar system.

It is also a reminder that the Earth is not immune to impacts from space.

The LHB should serve as a warning that we need to be prepared for future impacts, which could have devastating consequences for our planet.

**References:** * [NASA: Late Heavy Bombardment](https://www.nasa.gov/mission_pages/hubble/science/late-heavy-bombardment.html) * [Wikipedia: Late Heavy Bombardment](https://en.wikipedia.org/wiki/Late_Heavy_Bombardment) * [Scientific American: The Late Heavy Bombardment](https://www.scientificamerican.com/article/the-late-heavy-bombardment/)