In a recent study published in Science Advances, an international team of researchers led by the Paris Globe Institute of Physics estimate the amount of liquid water that might have existed on Mars billions of years ago, stating the entirety of the Red Planet might have once been covered with an ocean greater than 300 meters (950 feet) deep.
"At this time, Mars was bombarded with asteroids filled with ice. It happened in the first 100 million years of the planet's evolution. Another interesting angle is that the asteroids also carried organic molecules that are biologically important for life," said Dr. Martin Bizzarro, who is a professor from the Centre for Star and Planet Formation, and a co-author on the study.
While Mars is both a cold and dry world today, things were much different billions of years ago, as oceans and volcanoes were both active across its vast surface, and possibly life.
The researchers came to their findings by examining a billion-year-old meteorite on Mars, which was possible since the Red Planet lacks the plate tectonics that are seen on Earth. This means the meteorite was a part of the original crust of Mars.
"Plate tectonics on Earth erased all evidence of what happened in the first 500 million years of our planet's history. The plates constantly move and are recycled back and destroyed into the interior of our planet. In contrast, Mars does not have plate tectonics such that planet's surface preserves a record of the earliest history of the planet," Dr. Bizzarro explained.
Sources: Science Advances
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