The European and Japanese space agencies have launched their first mission to Mercury. And, though the tiny planet closest to the sun is relatively close to Earth, it will take the BepiColumbo spacecraft seven pretty complicated years to get there.
The reason it’s going to take so long, is that getting to Mercury is problematic. It’s small and it’s close to the sun, so it orbits the sun very quickly, and any spacecraft wanting to get close to Mercury has to avoid being pulled into our star by the sun’s gravity. So, BepiColumbo will have to book it to Mercury but also put on the breaks in certain places to keep from getting pulled off course by the sun. It will therefore maneuver its way to Mercury through a series of planetary flybys (one of Earth, two of Venus and six of Mercury itself) before slipping into orbit around the first planet.
ESA’s chart to explain BepiColumbo’s journey to Mercury
BepiColumbo consists of two parts that will separate once in orbit around Mercury. The European Space Agency’s Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO), from the Japan Aerospace Exploration Agency, plus a Mercury Transfer Module (MTM) to support the MPO and MMO on their way to the little rocky world. Once in orbit, and separated in position, BepiColumbo will study Mercury’s “composition, structure, magnetic field, formation and evolution” according to space.com.
First photo snapped from BepiColumbo as it makes its way to Mercury. October 20, 2018. Pictured: extended solar arrays (right) and an insulation-wrapped sun sensor on the MTM (left).
The MPO and MMO should be in orbit around Mercury in December of 2025. The MPO will orbit the planet every 2.3 hours while the MMO will take 9.3 hours per orbit. There’s a lot to be learned there. So, everybody settle in. See you in 7 years.