NASA's MAVEN Enters Mars' Orbit

September 22, 2014 1:06 AM EDT

Mars explorer MAVEN entered the Red Planet’s orbit late Sunday night, beginning a yearlong journey during which scientists hope to discover what happened to the Martian atmosphere.

Mission managers at NASA’s Goddard Space Flight Center in Greenbelt, Md., received confirmation of MAVEN’s arrival at about 10:25 p.m. E.T. — about a half-hour after it began slowing down from more than 10,000 m.p.h. to enter Martian orbit.

Narration of the orbital’s entry was broadcast beginning at 9:30 p.m. from Lockheed Martin Space Systems’ mission-operations center in Littleton, Colo. It took about 12 minutes for MAVEN’s signals to travel the 442 million miles to Earth.

MAVEN – standing for Martian Atmosphere and Volatile Evolution – launched from Cape Canaveral, Fla., on Nov. 18, 2013, and it will now take six weeks to turn itself on and test its systems.

After that, the $671 million, bus-sized craft will spend one (Earth) year assessing the planet Mars’ atmosphere, in hopes of discovering how the Martian atmosphere is changing now and, in doing so, understand how it has changed over billions of years.

Scientists believe that Mars and Earth were once sister planets, both of them green and wet. But, about 4 billion years ago, their fortunes diverged: as Earth incubated life in its thick, reassuring atmosphere, it’s thought that Mars somehow lost its magnetic field. That left it vulnerable to the spray of solar particles zooming through space, and, over time, scientists say, those particles winnowed the Martian atmosphere. Its land was buffed dry and brittle and its landscape turned freezing.

MAVEN is NASA’s 10th Mars orbiter mission, three of which have failed. Three other spacecraft are in Mars’ orbit, two of which are NASA missions (the 2001 Mars Odyssey and the 2005 Mars Reconnaissance Orbiter), and one of which is a 2003 European Space Agency mission.

Two rovers, Curiosity and Opportunity, are still active on Mars’ surface. Spirit, another rover, is still on the planet, but was deactivated in 2010.

“Hello ‪@MarsCuriosity and ‪@MarsRovers! #MAVEN is looking over you. (In ‪#Spirit),” tweeted the MAVEN mission, just after arrival.

Journey to the Red Planet: MAVEN Approaches Martian Orbit

An artist concept of NASA's Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Launched in November 2013, the mission will explore the Red Planet’s upper atmosphere, ionosphere and interactions with the sun and solar wind.Lockheed Martin/NASA

MAVEN Atlas V Launch — The United Launch Alliance Atlas V rocket with NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft launches from the Cape Canaveral Air Force Station Space Launch Complex 41, Monday, Nov. 18, 2013, Cape Canaveral, Florida. NASA’s Mars-bound spacecraft, the Mars Atmosphere and Volatile EvolutioN, or MAVEN, is the first spacecraft devoted to exploring and understanding the Martian upper atmosphere. Photo Credit: (NASA/Bill Ingalls)Bill Ingalls—NASA

NASA's MAVEN spacecraft, inside a payload fairing, is hoisted to the top of a United Launch Alliance Atlas V rocket at the Vertical Integration Facility at Cape Canaveral Air Force Station's Space Launch Complex 41 on Nov. 8, 2013.Kim Shiflett—NASA

Inside the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida, engineers and technicians perform a spin test of the Mars Atmosphere and Volatile Evolution, or MAVEN, spacecraft. The operation is designed to verify that MAVEN is properly balanced as it spins during the initial mission activities.Kim Shiflett—NASA

Engineers and technicians test deploy the twin solar arrays on the Mars Atmosphere and Volatile Evolution, or MAVEN, spacecraft at the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida on Sept. 23, 2013.Kim Shiflett—NASA

Technicians install the parabolic high gain antenna onto the MAVEN spacecraft in the Payload Hazardous Servicing Facility on Aug. 9, 2013. The antenna will communicate vast amounts of data to Earth during the mission.Jim Grossmann—NASA

A crane lifts the MAVEN spacecraft inside the Payload Hazardous Servicing Facility on Aug. 3, 2013. The spacecraft was flown to Kennedy Space Center for launch processing from Buckley Air Force Base in Colorado near the Lockheed Martin facility in Littleton, Colo.Tim Jacobs—NASA

An engineer positions a sling on the MAVEN spacecraft inside the Payload Hazardous Servicing Facility. MAVEN will be prepared inside the facility for its scheduled November launch to Mars. Tim Jacobs—NASA

The MAVEN Spacecraft Has Begun Orbiting Mars on a Yearlong Quest

Journey to the Red Planet: MAVEN Approaches Martian Orbit

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