Meteorites Reveal Story Of Martian Climate

Liquid water is not stable on Mars’ surface because the planet’s atmosphere is too thin and temperatures are too cold. However, at one time Mars hosted a warm and wet surface environment that may have been conducive to life. A significant unanswered question in planetary science is when Mars underwent this dramatic change in climate conditions.

New research by Lawrence Livermore National Laboratory (LLNL) cosmochemist Bill Cassata shows that, by looking at trapped gasses in ancient Martian meteorites, the timing and effectiveness of atmospheric escape processes that have shaped Mars’ climate can be pinned down. The research appears in Earth and Planetary Science Letters.

Cassata analyzed the Martian atmospheric gas xenon (Xe, in two ancient Martian meteorites, ALH 84001 and NWA 7034. The data indicate that early in Martian history there was a sufficient concentration of atmospheric hydrogen to mass fractionated Xe (selectively removed light isotopes) through a process known as hydrodynamic escape. However, the measurements suggest this process culminated within a few hundred million years of planetary formation (more than 4 billion years ago), and little change to the atmospheric Xe isotopic composition has occurred since this time.

This differs significantly from Earth, where Xe isotopic fractionation was a gradual process that occurred throughout much of planetary history, indicating that atmospheric dynamics on the two planets diverged early in the history of the solar system.

The fact that Xe fractionation on Mars ceased more than 4 billion years ago suggests that, on Mars, the hydrogen escape flux did not exceed the threshold required to continuously fractionate atmospheric Xe, as it did on Earth, potentially because Mars did not have sufficient atmospheric water available to generate atmospheric hydrogen via photodissociation.

“These data suggest that liquid water may not have been abundant on the Martian surface since a few hundred million years after planetary formation, and therefore Mars may has been cold and dry planet for the vast majority of its history,” Cassata said.

Author: Mitch Battros

Mitch Battros is a scientific journalist who is highly respected in both the scientific and spiritual communities due to his unique ability to bridge the gap between modern science and ancient text. Founded in 1995 – Earth Changes TV was born with Battros as its creator and chief editor for his syndicated television show. In 2003, he switched to a weekly radio show as Earth Changes Media. ECM quickly found its way in becoming a top source for news and discoveries in the scientific fields of astrophysics, space weather, earth science, and ancient text. Seeing the need to venture beyond the Sun-Earth connection, in 2016 Battros advanced his studies which incorporates our galaxy Milky Way - and its seemingly rhythmic cycles directly connected to our Solar System, Sun, and Earth driven by the source of charged particles such as galactic cosmic rays, gamma rays, and solar rays. Now, "Science Of Cycles" is the vehicle which brings the latest cutting-edge discoveries confirming his published Equation.