Mars has welcomed a new robotic visitor from Earth.

After a 10-month journey through deep space, NASA'sMAVEN probearrived in Mars orbit late Sunday (Sept. 21), on a mission to help scientists figure out why the Red Planet changed from a relatively warm and wet place in the ancient past to the cold, arid world it is today.

MAVEN, whose name is short for Mars Atmosphere and Volatile Evolution, fired its engines in a crucial 30-minute braking burn Sunday night, slowing down enough to be captured by the planet's gravity around 10:24 p.m. EDT (0224 GMT Monday, Sept. 22). [See images from the MAVEN mission]

"Congratulations! MAVEN is now in Mars orbit," MAVEN navigation team member Dave Folta, of NASA's Goddard Space Flight Center in Greenbelt, Maryland, announced to a round of cheers from mission control.

MAVEN joins three other operational probes in Mars orbit NASA's Mars Odyssey spacecraft andMars Reconnaissance Orbiter(MRO), and the European Space Agency's Mars Express. NASA also has two rovers actively exploring the planet's surface: the golf-cart-size Opportunity and its younger, bigger cousin, Curiosity.

And Mars orbit should get even more crowded just a few days from now. India's first-ever Red Planet effort, the $74 millionMars Orbiter Mission, is due to arrive Tuesday night (Sept. 23).

The $671 million MAVEN mission blasted off as planned on Nov. 18, 2013, though not without a bit of prelaunch drama.

Liftoff preparations were frozen when the government shutdown went into effect on Oct. 1, 2013, sending ripples of anxiety through the MAVEN team and the global planetary science community. But NASA granted MAVEN an emergency exception a few days later, getting things back on track. (The shutdown ended on Oct. 17, 2013.)

MAVEN is the first NASA spacecraft dedicated to studying the upperatmosphere of Mars, NASA officials said. The mission will use MAVEN's three suites of scientific instruments to measure and characterize gas escape from the Martian atmosphere, which was once relatively thick but is now just 1 percent as dense as that of Earth at sea level.

MAVEN's observations should help scientists get a better handle on what happened to the water that flowed and sloshed across Mars billions of years ago whether it escaped into space or sank into the planet's crust, said mission principal investigator Bruce Jakosky, of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. [7 Biggest Mysteries of Mars]

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