From NASA Reports
NASA In Brief -- Spacecraft orbiting Mars
Artist's concept: NASA.
NASA’s study of the red planet’s upper atmosphere began in earnest Sept. 21, when a spacecraft entered the orbit of Mars.

     NASA confirmed that after a 10-month journey the spacecraft known as Mars Atmosphere and Volatile Evolution (MAVEN) had entered the planet’s orbit. The space agency tracked MAVEN with data at the Lockheed Martin Corp. operations center in Littleton, Colorado, as well as at NASA’s Jet Propulsion Laboratory in Pasadena, California. The telemetry and tracking data were received by NASA’s Deep Space Network antenna station in Canberra, Australia.
     The spacecraft will start a six-week phase that includes maneuvering into its final orbit and testing instruments and science-mapping commands. It will then begin its one Earth-year mission -- taking measurements of the composition, structure and escape of gases in Mars’ upper atmosphere and the planet's interaction with the sun and solar wind. This is the first spacecraft dedicated to exploring the upper atmosphere of Mars.
     The primary mission includes five “deep-dip” campaigns, in which MAVEN’s orbit will be lowered from 93 miles (150 kilometers) to about 77 miles (125 kilometers). These measurements will provide a picture of where the upper and lower atmospheres meet, giving scientists a profile of the upper tier.
     To learn more about the mission, see NASA's website.  

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