All evidence points to Mars having had a carbon dioxide-rich atmosphere billions of years ago, but insufficient carbonates in Martian soil challenge this theory. Now, a new study using data from ...

For years, scientists have puzzled over how Mars lost the thick atmosphere it once had. That atmosphere was essential for liquid water to exist on the planet’s surface, billions of years ago.

However, about 3.5 billion years ago, Mars underwent a drastic transformation. The atmosphere thinned, temperatures dropped, and the planet lost its surface water.

For decades, scientists have puzzled over why Earth stayed warm and alive while Mars turned cold and dry. Both planets began with similar ingredients—rocky surfaces, carbon, water, and sunlight—but ...

Sometime in the past 3.5 billion years, Mars' atmosphere thinned and its water either froze or was lost to space. The question is, how did that happen?

It happens when ions are accelerated by the electric field of the Solar wind into the atmosphere of a body – like Mars – that is unprotected by a global magnetic field.

As I said earlier, there was a time when Mars probably had both water and a more friendly atmosphere. Then something happened, and the planet lost its magnetic field.

The video below shows how Mars loses atmosphere -- 25% is lost from a polar plume, while 75% of the loss occurs at the long tail.

While life on Earth was becoming more complex and diverse, Mars was also changing. Mars lost much of its atmosphere and lost all of the liquid water on its surface.

To truly understand how Mars' atmosphere has changed over the years, researchers took a closer look at nine years' worth of data. The data was captured by NASA's MAVEN, which entered a Mars-bound ...

New research suggests Mars' missing atmosphere -- which dramatically diminished 3.5 billion years ago -- could be locked in the planet's clay-covered crust. Water on Mars could have set off a ...

The warm, wet periods were driven by crustal hydration, or water being lost to the ground, which supplied enough hydrogen to build up in the atmosphere over millions of years. During the fluctuations ...