From its blood-like hue to its potential to sustain life, Mars has intrigued humankind for thousands of years. Learn how the red planet formed from gas and dust and what its polar ice caps mean for life as we know it.
And find out why Mars, a planet with an iron-rich crust and trace amounts of oxygen in its atmosphere, is red. National Geographic introduces one of our closest neighbors in this Mars 101 video.
Then travel To Mars and Back In 150 Seconds, see what Mars look like 4 billion years ago, and take A Fictive Flight Above Real Mars.