SwRI Links 800-Million-Year-Old Asteroid Breakup to Inner Solar System Bombardment
Updated
Updated · ScienceDaily · Jul 19
SwRI Links 800-Million-Year-Old Asteroid Breakup to Inner Solar System Bombardment
3 articles · Updated · ScienceDaily · Jul 19
Summary
A new SwRI-led study says the breakup of the Eulalia parent asteroid about 800 million years ago could explain a major impact surge on Earth, the Moon and Mars.
Models point to the asteroid's position near Jupiter's 3:1 resonance as the trigger: about half the fragments were injected quickly into planet-crossing orbits, with another 25% drifting in over 100-150 million years.
Lunar crater ages and Apollo impact-glass samples had already suggested a bombardment spike around that time, and the Moon's relatively unchanged surface preserves that record far better than Earth.
Researchers estimate Earth would have been hit by roughly 20 large objects for every comparable impact on the Moon, though most terrestrial evidence has since been erased by tectonics, volcanism and weathering.
The timing overlaps with widespread cooling and major biological shifts on Earth, while on Mars the impacts may align with seismic upheaval and increased volcanism, making the event a target for further study.
Did a 150-million-year-long asteroid storm 800 million years ago trigger Earth's great ice age and alter the course of life?
An ancient asteroid family near a gravitational 'escape route' battered Earth for millennia. Are other such long-term threats lurking in our solar system?
The Eulalia Event: Tracing an 800-Million-Year-Old Asteroid Breakup and Its Lasting Effects on the Inner Solar System
Overview
Recent research led by the Southwest Research Institute has revealed that about 800 million years ago, a massive asteroid called the Eulalia parent body broke apart near Jupiter’s 3:1 mean-motion resonance. This breakup sent many fragments into planet-crossing orbits, causing a dramatic spike in impacts across the inner solar system. The Moon’s heavily cratered surface preserves evidence of this ancient bombardment, which likely affected Earth and Mars as well. This event, much larger than the famous Chicxulub impact, highlights how catastrophic asteroid collisions can shape planetary surfaces and influence the history of life and geology on Earth.