deuterium

For many years, scientists have argued about the origin of water on Earth: available or brought by meteors.

Scientists for the first time found water molecules at the time of new Earth formation about 4.6 billion years ago under a depth of 2,900km in the ground.

Not only Mars, but Venus also had water on it. And so far, experts have found the reason why water disappears.

Mars exploration robots deploy the final equipment. Soil analysis showed organic compounds of uncertain origin.