Image: Mercury's double-ring basin Rachmaninoff. Images of this basin are being featured as the planetary geomorphology images of the month on the IAG Web site.

The MESSENGER mission team has recently finished a two-week flight test to ensure that the spacecraft is ready for orbital operations. On 18 March 2011, MESSENGER will become the first spacecraft to enter into orbit about Mercury, embarking on a year-long mission to study the planet. The completion of this test provides a verification of the tools, processes, and procedures that are needed to conduct flight operations at Mercury.

The flight test took place from 17 August to 29 August. In order to force the spacecraft to rotate in space and to gather science data in a manner similar to the operations the probe will experience during the orbital phase of the mission, the ephemerides used on onboard the spacecraft had to be modified in order to “convince the spacecraft that it was in Mercury orbit.” The science team also chose this particular two-week period as the Sun and Earth geometries were similar to those MESSENGER will see during the orbital phase of the mission. Principal Investigator Sean Solomon commented, “Our entire cruise phase and even the three Mercury flybys have only been warm-ups for the main event of our mission. These two weeks of flight tests have been our dress rehearsal, to ensure that our spacecraft and our flight team are ready for opening night.”

Postdoctoral associate Christian Miller joined DTM this week. He received his Ph.D. from the MIT/ WHOI Joint Program in Oceanography in 2009. Miller’s research interests focus on the development and application of novel isotope systems to geochemical problems. A significant portion of his Ph.D. research involved the development of stable isotope analysis of Re and the identification of Re isotope variation in nature. At DTM, Miller will work on dating chondrules—some of the oldest materials in the solar system—with several radioactive chronometers. Chondrules have been dated with single decay systems before and have shown million-year variations in age. This is unexpected in light of prevailing models of solar system formation. Using several decay systems on the same chondrule will allow researchers to say with certainty that age variations are real; if they are the result of mixing of materials of different ages; or if they are recording events that occurred after the formation of the chondrule.