A U.S. spacecraft has arrived at Mars to study the planet’s upper atmosphere and help scientists answer questions about how its climate has changed over time.

The craft named the Mars Atmosphere and Volatile Evolution, or MAVEN, completed a 10-month, 711 million-kilometer journey late Sunday.

It will measure the rates at which gases escape the Martian atmosphere into space.  

Bruce Jakosky, who is leading the science side of the mission, said the goal is to understand what caused significant changes to the climate on Mars during the past few billion years.

“So we’re looking at what happens at the top of the atmosphere, how the processes involving the sun and the solar wind affect the gas at the top of the atmosphere and strip it away to space.  So in essence, that’s our goal, to answer the question where did the water go, where did the carbon dioxide go?” said Jakosky.

MAVEN will take six weeks to settle into its orbit around Mars and test its instruments before beginning the one-year mission, which carries a price tag of $671 million.

There are three other spacecraft currently orbiting Mars – two American and one European. Another from India is due to arrive Wednesday.
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