4 billion years ago, during a period known as the Late Heavy Bombardment, comets and asteroids (some as large as 200 miles across) are now believed to have enhanced climate conditions of Mars through their impacts. While these climate changes weren’t permanent, they did make a huge impact according to new studies conducted by the University of Colorado.
Boulder professor Stephen Mojzsis says that if early life on Mars had been as barren and cold then as it is today, these massive impacts on the planet’s surface would have created enough heat to actually melt ice on the subsurface. These regional hydrothermal systems would have been very similar to those located in Yellowstone National Park, a park that contains chemically powered microbes. These microbes are known to be able to survive some drastic temperatures, including boiling within the hot springs.
While running water on the surface of Mars is no new discussion, these gigantic impacts could have increased the atmospheric pressure of the entire planet. This temporary change could have heated up Mars just enough to start a new dormant water cycle. If life were present at the time, professor Mojzsis states these comets and asteroids would have been very beneficial to life on the planet. There is no current evidence that can prove that life was, in fact, present.
Mojzsis’ study was conducted with the help of Oleg Abramov, a U.S. Geological Survey researcher located in Flagstaff, Arizona. Abramov was once a research scientist at Colorado University who worked under Mojzsis. They say most of the “heavy bombardment” happened just under 4 billion years ago when the then developing solar system was on the move, spinning and throwing comets, asteroids, planets and moons on a large scale. Evidence of this time is still very much alive on the surfaces of Mercury, Mars and the Moon. Large craters tell the story of this eventful time.
With the help of Abramov, Mojzsis used something called the Janus supercomputer cluster located within the Computing facility at his University to recreate the 3D models for the study. The pair viewed temperatures underneath millions of craters within their simulations to track heating and cooling and compared how impacts on Mars affected the planet when coming from varying angles and velocities. These tests, Mojzsis says, show evidence that none of the impacts would be able to keep Mars warm over the long term.
In 2009, a study conducted by Mojzsis and Abramov displayed the Late Heavy Bombardment period and its affect on planet Earth. The turmoil of the inner solar system did not have the ferocity to destroy early life on our planet; the Bombardment may have actually given a boost to present life. The world’s oceans are to thank for the safety of the planet, as they would have needed to fully boil in order to dissipate.
NASA and the John Templeton Foundation funded the new Mars study and Mojzsis was recently offered a grant of $800,000 from the Foundation for Applied Molecular Evolution. The grant was supplied to help better understand Earth in its earliest stages, as well as life’s beginning.
Mojzsis plans to collaborate with the California Institute of Technology and NASA’s Jet Propulsion Laboratory in Pasadena in May 2016 to talk about potential landing sites and research goals for a rover mission planned for Mars in 2020. These types of studies will provide valuable information about where we fit in the solar system, Mojzsis explains. His current focus is modeling similar bombardment situations on the planets Mercury and Venus. The studies will help us better understand the evolution of inner solar systems. In turn, this research will assist in understanding planets around other stars in the galaxy.
This study was published in Earth and Planetary Science Letters.