NASA's 4-year-old atmosphere-sniffing Mars Atmosphere and Volatile Evolution (MAVEN) mission is embarking on a new campaign today to tighten its orbit around Mars. The operation will reduce the highest point of the MAVEN spacecraft's elliptical orbit from 3,850 to 2,800 miles (6,200 to 4,500 kilometers) above the surface and prepare it to take on additional responsibility as a data-relay satellite for NASA's Mars 2020 rover, which launches next year.
