The longest JAXA projectOvercoming a lot of difficulties
by the international collaboration
Former Project Manager of MioHajime Hayakawa

Mercury Exploration Working Group was formed in 1997

The launch of BepiColombo is around the corner. It just reminds me that the Mercury Exploration Working Group was started on June 1997, and we designed Japanese Mercury Exploration Mission on November 1998. After then, ESA proposed a joint mission of Mercury exploration on November 1999, and ISAS wished to join the proposal on September 2000. It has been 21 years since we were involved in the Mercury exploration, and 18 years has passed from we started the BepiColombo mission. Both the ESA side and the JAXA side, most of the initial core members has already retired, and it reminds me of those days.

A group photo at the International Mercury Exploration Workshop in JAXA/ISAS (Sep. 2001)

Repeated changes of plan

We planned to launch two orbiters (MPO and MMO) and one lander (MSE) in 2010, and aimed to insert Mercury orbit in 2014 in the initial plan. However, we stopped developing the lander at an early stage due to the technical difficulties and its short lifetime, therefore, we have changed our plan to the current two orbiters’ mission. The schedule of launch and Mercury orbit insertion have also been delayed to 2012 and 2016, respectively. Even after, we repeatedly delayed the launch schedule due to technical problems, and we sometimes encountered crises that would end the mission, but we finally got over to came here. Though, Mercury orbit insertion has been planned at the end of 2025, and the science operation will be started from the beginning of 2026. If we compare the marathon, we have just reached the starting line now, and keep us on our toes.

The initial concept of the BepiColombo spacecraft. The MSE lander was included.

Overcoming a lot of difficulties

This is the first big collaboration with ESA, to provide “a spacecraft” instead of “an instrument”. At the beginning of cooperation, since we did not understand ESA colleagues well and their backgrounds, we sometimes disputed each other, and felt that it is better to smash a desk and get out the meeting. We have gradually understood what they can do and what they cannot do, and everything has gone on smoothly. After all, ESA project and MMO project were able to build a firm relationship. Actually, they have understood our claims and persuaded other departments of ESA. Still, we were sometimes surprised because of different ideas of common sense (perhaps, they were also surprised.)
Overcoming a lot of difficulties, it makes me think how far we have come. We still have a long way to go but we look forward to try to shed light on the mystery and explore brand-new findings.

Posing together with Ulrich Reininghaus, ESA Project Manager (Jun. 2015)