海角大神

Billions of years ago, Mars was a very different place. But at some point, the strong magnetic field that protected the red planet mysteriously disappeared, allowing 鈥渟olar winds鈥� to swoop in and run amok. Scientists guess that the resulting climate change is why Mars now has such a weak atmosphere and no liquid water on the surface of the planet.

To help investigate this theory, the National Aeronautics and Space Administration (NASA) unveiled its latest mission to Mars: a satellite that will circle Earth鈥檚 neighbor and taste the upper layers of its atmosphere. Called the Mars Atmosphere and Volatile EvolutioN, or MAVEN, this spacecraft will 鈥減rovide the first direct measurements ever taken to address key scientific questions about Mars鈥檚 evolution,鈥� says Doug McCuistion, director of Mars exploration. The satellite will also double as a communications array for other missions on the planet, such as relaying information to robotic rovers on the ground.

NASA scheduled MAVEN鈥檚 blastoff for 2013 and plans for the craft to reach Mars鈥檚 orbit by the fall of 2014.