Mars had a rough infancy, with giant meteorites pummeling the planet soon after its formation.
Now, an international team of researchers has found evidence that this bombardment may have ended sooner than previously expected, changing what we thought we knew about the Red Planet’s historic ability to host life — and maybe even providing evidence that Mars was inhabited before Earth was.
In a paper published Monday in the journal Nature Geoscience, researchers led by a team from Western University detail their analysis of the oldest-known Martian minerals, which were embedded in meteorites thought to have originated from the planet’s southern highlands.
The mineral grains appeared unchanged since the time of their formation, which led the researchers to conclude that the life-inhibiting meteorites likely stopped hitting Mars about 4.48 billion years ago, contradicting previous assumptions the planet was hit by a “late” phase of meteorites about 3.8 billion years ago.
Based on this new timeline, the researchers believe there was a 700-million-year period between 3.5 billion and 4.2 billion years ago when Martian life could’ve thrived — a full 500 million years before the earliest evidence of life on Earth.
READ MORE: Research resets timeline for life on Mars [Western University]
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