Mercury Mission Moves Forward
25 Jul 2003
(Source: Institute of Space and Astronautical Science)
International Joint Mercury Exploration Mission "BepiColombo" Moves to Next Stage after Review by SAC
July 25, 2003
The only direct spacecraft observation of the planet Mercury was provided by the US Mariner 10's flyby in the 1970s. Mariner 10 revealed many unexpected findings about the planet nearest the Sun, including, for example, the unexpected presence of a magnetic field and magnetospheric activities. Further investigation into those findings has been on hold for over 30 years.
The Mercury exploration working group was formed at ISAS in 1997. It developed a Japanese-initiated Mercury exploration plan the following year. In 1999, ESA (European Space Agency) proposed a joint Mercury exploration, and ISAS agreed to participate in 2000. In the same year, the BepiColombo mission was formally selected as one of ESA's cornerstone missions. The mission was formally authorized by ISAS in early 2002, following submission to and review by the Space Science Committee in 2001.
The BepiColombo mission is the first, full-fledged collaborative project by Japan and Europe with shared exploration systems. The mission is very ambitious. A total of 3 explorers (2 orbiters and 1 lander) will be sent to Mercury. For the first time, the mission will conduct a multifaceted and comprehensive observation of the magnetic field, magnetosphere, interior and surface of Mercury, the least known of all the earth-type planets. Japan will be responsible for one of orbiters, the Mercury Magnetospheric Orbiter (MMO), and ESA will be responsible for the launcher, interplanetary cruising engine, the Mercury Planetary Orbiter (MPO) and the lander (Mercury Surface Element or MSE). Japan and ESA will develop the observation instruments in competition. Observation will be planned and executed by both teams. The launch is planned for FY2010 and observation is scheduled to start in FY2014.
In response to our request to move to the research and development (PM) phase in FY2004 following fundamental research in FY2003, the Mercury Exploration Project Evaluation Subcommittee under the Planning and Evaluation Section of the Space Activities Commission (SAC) was held on June 13 and 24. Chaired by Prof. Katsuhiko Sato, University of Tokyo, the subcommittee made a full and detailed review of the BepiColombo project from many angles including: its meaning; target and priority; compatibility with the requirements of overall space science policy; development policy; validity of basic design requirements and system selection; risk management; implementation scheme; and resource allocation. To our delight, SAC approved the project for the PM phase. An earlier US mission MESSENGER (launch in 2004, start of observation in 2009) plans to study Mercury's environment, interior and surface. Our mission will observe globally Mercury's magnetic field construction. It is expected that the observation will produce significant results because it allows us to compare Mercury with Earth, and clarify the commonality and specificity of the planet's magnetosphere by precise, high-resolution observation.
We are going to commence full-scale development of the project in close collaboration with ESA, researchers in Europe and universities/research institutions in Japan. We would like to ask for the support and cooperation of all those concerned.