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MESSENGER (Mercury Surface, Space Environment, Geochemistry and Ranging)

MESSENGER probe at Mercury
A NASA probe to investigate Mercury from an orbit around the planet. Successfully launched on Aug. 3, 2004, MESSENGER will make two flybys of Venus, one of Earth,and three of Mercury during a seven-year voyage that will position it for orbital insertion in 2011. During its nominal one-year science mission around the innermost planet, the probe will image the surface with a high-resolution camera, analyze the planet's surface composition with X-ray, gamma-ray, infrared, and neutron spectrometers, study the magnetic field with a magnetometer, and determine the height of features with a laser altimeter. The only previous mission to Mercury was Mariner 10 in 1974. During the Mariner 10 passes, detailed data was only collected for half of the planet's surface. MESSENGER, by contrast, will conduct an in-depth study of Mercury in its entirety. Carrying seven scientific instruments, it will provide the first images of the whole surface. The 1.2-tonne, $426m probe will carry its own sunshade to protect it from the planet's high daytime temperatures.

MESSENGER should eventually have company in orbit around Mercury. BepiColombo, a collaboration between Europe and Japan, is a twin spacecraft set for launch to the planet early in the next decade.

External site

MESSENGER Home Page (Johns Hopkins Applied Physics Laboratory)

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