Mars may have supported life more recently than previously believed, says new study

A recent study from Harvard’s Paleomagnetics Lab, published in Nature Communications, reveals that Mars' magnetic field may have persisted longer than previously thought, enhancing the possibility that Mars was once habitable.

The research team suggests that Mars’ magnetic field - vital for shielding life from harmful solar radiation - may have lasted until 3.9 billion years ago, instead of the previously estimated 4.1 billion years, hinting at an extended period during which life could have thrived on the Red Planet.

Using computer simulations and modeling, the researchers examined Mars' “dynamo,” a magnetic field generated by the movement in its iron core, similar to Earth’s. By studying Martian basins, they found that many craters were likely created during a time when Mars’ dynamo was reversing polarity - a phenomenon also observed on Earth.

Sarah Steele, lead researcher at Harvard, emphasized that planetary magnetic fields offer crucial insights into the deep interiors and early histories of planets across the solar system.

This 200-million-year extension overlaps with the period when water is believed to have been abundant on Mars’ surface, as evidenced by NASA rover findings. However, the loss of a strong magnetic field ultimately left Mars vulnerable to solar winds, eroding its atmosphere and depleting its water supply, making the environment less capable of sustaining life.

While scientists continue to investigate life’s potential on Mars, another NASA study recently indicated that microbial life might find refuge beneath Mars' ice. The research proposes that sunlight penetrating shallow layers of water ice could support photosynthesis in small meltwater pools just beneath the surface.

This study, focusing on Mars’ two types of ice - frozen water and frozen carbon dioxide - considered water ice as a potential home for microbial life.