Did Mars Have Oceans, Glaciers & Freezing Temperatures 3 Billion Years Ago?

 A new study might have finally solved a Mars paradox by suggesting that the planet could have been cold while still housing a northern ocean.

The Mars 'cold and wet' paradox that has challenged scientists for decades may have finally come to an end. Evidence of Mars’ water-shaped surface suggests the planet once had an abundance of oceans, rivers, and lakes, but temperatures on ancient Mars when the sun was dimmer were below zero and would have frozen all water.

Perseverance and Curiosity rovers have looked for signs of water on Mars to answer the big question of whether there once was, and still is, life on the Red Planet. Rovers constantly encounter undeniable evidence of water, but still no evidence of life. With dried-up lake basins, cooling volcanic magma that could have only been formed while submerged in water, and even giant tsunamis, NASA has seen it all with Mars.

In a Proceedings of the National Academy of Sciences paper, a team of researchers from France, the US, and Sweden say that ancient Mars was cold and wet. The researchers managed to successfully run simulations revealing that Mars could have sustained liquid water despite cold temperatures, after modeling Mars three billion years ago during a period known as the Late Hesperian.

Northern Ocean And Southern Glaciers

Modeling simulations of Mars is not a new approach to understanding how water once flowed on the Red Planet, but the team of researchers succeeded where NASA Mars experts failed. The researches say that the problem was that previous studies were based on the assumption that, for oceans to exist, planets need to be warm like Earth. Likewise, the suggestion that a planet has no water because it is cold is another misleading assumption. Instead, the team argues that there is a third option that solves the paradox - a cold and wet planet.

In terms of how a cold planet could host liquid water without it freezing, the new models reveal that oceans can exist in these low temperatures if there is enough hydrogen in the atmosphere. If just 10 percent of the atmosphere was hydrogen sourced from volcanoes or cosmic impacts, and the rest was carbon dioxide, this would likely have created a small greenhouse effect.

Mars lost its water when it lost its magnetic field and its atmosphere was weakened by bombarding solar wind. Essentially, extreme storms and climate transferred water from the surface to the lower atmosphere and it later escaped into space. Three billion years ago, according to the simulation, the northern basins of Mars housed a massive ocean as well as a never-ending field of glaciers flowing back to the ocean.