2
8
Oceans on Mars formed 300 million years earlier than first thought, according to a new study.
Research suggests the planet's water systems appeared after a series of massive volcanic eruptions permanently altered the planet's surface around 4 billion years ago.
The formation of Mars's oceans was linked to the violent rise of Tharsis, a 3,000-mile- (5,000km)-wide string of volcanoes that make up the solar system's largest volcanic system.
Tharsis likely spewed gases into the atmosphere that created a global warming or greenhouse effect, which allowed liquid water to exist on the planet.