Mars wasn’t always the cold, rust-colored desert we see today. Billions of years ago, it may have been a blue world, wrapped in thick clouds and dotted with rivers, lakes, and oceans deep enough to cover the planet. But over time, something went terribly wrong.
Mars lost its magnetic field, its atmosphere thinned, and its water vanished into space or froze beneath the surface. Today, only dry valleys, frozen poles, and dusty skies remain as evidence of its once-lively past. In this gallery, we uncover how Mars lost its water, and what its fate might teach us about Earth’s own future. Curious? Click to know more.