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. Today, ...

Prefer Newsweek on Google to see more of our trusted coverage when you search. Mars' missing atmosphere may be locked up in the planet's clay-rich surface, a new study by MIT geologists has suggested.

Mars wasn’t always the cold desert we see today. There’s increasing evidence that water once flowed on the Red Planet’s surface, billions of years ago. And if there was water, there must also have ...

Mars is blanketed by a thin, mostly carbon dioxide atmosphere — one that is far too thin to keep water from freezing or quickly evaporating. However, geological evidence has led scientists to conclude ...

Add Yahoo as a preferred source to see more of our stories on Google. Mars just gave up one of its oldest secrets — and it took a decade, a spacecraft, and a cosmic cannonball to catch it in the act.

(NEW YORK) — Mars is a cold, dry, desert-like planet. But billions of years ago, scientific evidence suggests that it had a thick atmosphere, which kept it warm enough to support flowing water on its ...

A key tracer used to estimate how much atmosphere Mars lost can change depending on the time of day and the surface temperature on the Red Planet, according to new observations by NASA-funded ...

A NASA rover taking rock samples on Mars has uncovered a plentiful mineral that was invisible to orbiters studying the Red Planet from space. Scientists say the discovery of siderite, a type of iron ...

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 chain ...