This artist’s rendition shows NASA’s MESSENGER spacecraft flying by Mercury, the innermost planet
Credit: NASA/JHUAPL/Carnegie Institution of Washington
On 3 August 2004, NASA’s MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft launched from Cape Canaveral Air Force Station, for a daring mission that would take the small probe dangerously close to the surface of Mercury, to begin an unprecedented exploration of the innermost and smallest planet.
MESSENGER journeyed in space along a 7.9-billion-kilometers path that included 15 revolutions around the Sun, one Earth flyby, two Venus flybys, and three Mercury flybys, before entering Mercury orbit in March 2011.
“We have operated successfully in orbit for more than three Earth years and more than 14 Mercury years as we celebrate this amazing 10th anniversary milestone,” said MESSENGER Mission Operations Manager Andy Calloway. “The MESSENGER spacecraft operates in one of the most challenging and demanding space environments in our Solar System, and we have met that challenge directly through innovation and hard work, as exemplified by the stunning discoveries and data return achievements. Our only regret is that we have insufficient propellant to operate another 10 years, but we look forward to the incredible science returns planned for the final eight months of the mission.”
MESSENGER is only the second mission to Mercury during the whole Space Age. NASA’s Mariner 10 spacecraft flew by Mercury three times in 1974 and 1975, and obtained detailed data on nearly half the planet’s surface. MESSENGER took advantage of an innovative trajectory design, lightweight materials, and miniaturization of electronics, all developed in the three decades since Mariner 10’s voyage to Mercury.
MESSENGER Deputy Principal Investigator Larry Nittler said that the mission has rewritten scientists’ understanding of the planet “and given us plenty of surprises.” “MESSENGER observations have also shown that Mercury’s surface was shaped by volcanic activity, identified unique landforms shaped by loss of volatile materials, and confirmed the presence of large amounts of water ice protected from the Sun’s heat within permanently shadowed impact craters near the planet’s poles.
References
www.nasa.gov/