Chilly, damp Mars may have hosted an ancient ocean

A cold, wet Mars could have supported an ocean in the northern parts of the Red Planet three billion years ago, a new study finds.

New 3D climate simulations of the planet’s ancient atmosphere and water suggest a liquid ocean once existed in the northern lowland basin of Mars. This ocean potentially persisted even when average global surface temperatures were below the freezing point of water, the peer-reviewed work suggests.