Japan’s space agency, the Japan Aerospace Exploration Agency (JAXA), has announced the BepiColombo mission to the planet Mercury will be launched on October 19 from French Guiana, at 22:45 local time.
The launch will take place using Arianespace’s Ariane 5 rocket, which will carry two payloads, JAXA’s Mercury Magnetospheric Orbiter known as MIO, and the European Space Agency’s (ESA) Mercury Planetary Orbiter (MPO). Both orbiters are the part of a JAXA-ESA mission to Mercury known as BepiColombo. This will be both Japan’s and Europe’s first mission to Mercury, which has only been visited by NASA’s Mariner 10 (1973) and Messenger (2004) so far.
The two spacecraft will take seven years to reach Mercury, where they will make six flybys of Mercury and conduct a year-long study of the planet. Along the way, BepiColombo will make a flyby of Earth and two flybys of Venus.
To get to Mercury, BepiColombo will use the gravities of Earth, Venus and Mercury in combination with the thrust provided by solar-electric propulsion (SEP). During the voyage to Mercury, the two orbiters and a transfer module, consisting of electric propulsion and traditional chemical rocket units, will form one single composite spacecraft.
Once the single-unit spacecraft reaches Mercury in 2025, the transfer module will be separated and the composite spacecraft will be brought to into polar orbit around the planet. When the MIO’s orbit is reached, the MPO will separate and lower its altitude to its own operational orbit.
There, MIO will study Mercury’s magnetic field, its thin atmosphere, and observer interplanetary space and shock waves near the sun. MPO, meanwhile, will chart the planet’s mineralogy and elemental composition, amongst other missions.