Life could have thrived 3.5 to 4.2 billion years ago, preceding the earliest evidence of life on Earth by 500 million years.
After the planets formed in our solar system, the abundance and size of the meteorites in the solar system decreased. This gradual decline opened a window in which the conditions for the emergence and the permanence of life were right.
However, there are different ideas about when the heavy meteorites have stopped. Some scientists believe that the planets underwent a later stage of bombardment 3.8 billion years ago.
For the new study, the researchers examined the oldest known mineral grains of meteorites, which they believe originated from the southern highlands of Mars. Looking at them at the atomic level, the researchers found that the minerals were unchanged since they formed and crystallized near the Martian surface.
The grains were compared to areas on Earth and on the Moon that were hit by meteorites. More than 80% of the mineral grains were altered by extreme pressure and temperature.
The researchers believe that the samples show that heavy meteorites have ceased to hit Mars before Mineral grains were formed. This means that the surface of Mars could have been habitable even in times of abundant water.
"Huge meteorite impacts on Mars 4.2 to 3.5 billion years ago may have accelerated the release of early waters from within the planet" The Stage for Life-Forming Reactions, "said Desmond Moser, study author and adjunct professor at the Department of Earth Sciences and Geography of the Western University," This work may show good locations where samples from Mars can be sent back. "
The University's Moser-led Zircon and Accessory Phase Laboratory was critical to the study.
NASA's Mars 2020 Rover, which will launch next summer, will collect samples and stow them on the Martian surface so they can return to Earth later. Moser hopes his research will shed light on this Nnten where these samples can be collected.