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Updated: Jul 21, 2026
09:44
Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System
Published on: June 5, 2014
Impact seeding and reseeding in the inner solar system.
Brett Gladman1, Luke Dones, Harold F Levison
1Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada. gladman@astro.ubc.ca
Astrobiology
|August 5, 2005
Summary
Impacts can eject microbes from Earth, potentially seeding Mars and Venus. This ejected material also returns to Earth, offering a survival refuge for early life following extinction events.
Area of Science:
- Astrobiology
- Planetary Science
- Geology
Background:
- Asteroidal and cometary impacts can liberate terrestrial material.
- Microorganisms within ejected material may survive space transit.
Purpose of the Study:
- To model the distribution of impact ejecta in the inner Solar System.
- To assess the viability of biological seeding on other planets.
- To evaluate the potential for terrestrial life to survive impacts via space refuge.
Main Methods:
- Simulations of ejecta distribution over 30,000 years.
- Calculation of material delivery rates to Earth, Mars, and Venus.
- Analysis of impact speeds and ejected mass fractions.
Main Results:
- Ejected terrestrial material disperses rapidly throughout the Solar System.
- 0.1% and 0.001% of ejecta reach Venus and Mars, respectively, within 30,000 years.
- Approximately 1% of ejected mass returns to Earth, offering a potential survival mechanism.
Conclusions:
- Impact ejecta can facilitate the biological seeding of other planets.
- Terrestrial life may have a refuge in space during catastrophic impact events.
- Early bacterial life could have survived extinction events through this mechanism.
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