NASA's newest robotic explorer, Maven, is on its way to Mars.
The Maven spacecraft blasted off aboard an unmanned rocket from Cape Canaveral on Monday. It will take Maven 10 months to reach Mars following a journey of more than 440 million miles.
This is NASA's 21st mission to Mars since the 1960s. But it's the first one devoted to studying the Martian upper atmosphere.
Scientists want to know why Mars went from being warm and wet during its first billion years, to the cold and dry place it is today. The early Martian atmosphere was thick enough to hold water and possibly support microbial life. But much of that atmosphere may have been lost to space, eroded by the sun. Maven may solve this case of mysterious climate change.