Development of a visible and near-infrared spectrometer for Selenological and Engineering Explorer (SELENE)

Although the Moon has been investigated from the Earth, manned Apollo program, and numerous unmanned spacecraft including latest Clementine and Lunar Prospector, unresolved issues on the origin and evolution of the Moon still exist. To find clues or hopefully answers to these issues, Japan will send, to the Moon, an orbiting spacecraft called Selenological and Engineering Explore (SELENE) equipped with a suite of state-of-the-art mission instruments. Spectral Profiler (SP) is one of the instrument onboard SELENE, and will obtain 0.5-2.6 micrometers continuous reflectance spectra of the lunar surface just below SELENE with 500 m swath. As major minerals on the Moon, pyroxene, olivine, and feldspar, have diagnostic spectral features in this spectral region, SPs spectra will provide us information on mineral/rock distributions on the Moon surface globally. Such information from SP will, in combination with other instruments, clarify elemental/compositional characteristics of the lunar surface. This will contribute so much to depict a clear picture of the origin and the evolution of the Moon. To accomplish these scientific goals, engineering issues such as performance requirements and calibration procedures were discussed intensively and comprehensively among SP scientists and engineers. And based on such discussions, the basic instrument design of SP was determined and PM development was started in FY 1998. In FY 1999 and 2000, PM testings are being conducted. FM design will start in late- 2000. In the presentation, current status of SP development will be reported together with background information on SELENE, SP, and the science of the Moon.