The objective of this ambitious and complex mission is to explore an as yet unknown planet in order to understand its formation and evolution in a context of comparative planetology.
Le LESIA has designed and built two instrumental subsets of the probe : VIHI, a spectro-imager in the visible and near infrared designed to make a complete mineralogical mapping of the surface of Mercury, and SORBET, in charge of measuring radio waves in the plasma around Mercury.
The stakes of this near-Earth passage are crucial. This will allow the probe to decelerate and inflect its trajectory towards the Inner Solar System and Mercury. This is the first of the 9 gravitational assistances needed to bring BepiColombo to its destination. The electric propulsion used (a first for an ESA mission) will not provide enough energy to reach Mercury and multiple planetary overflights are required : 1 time Earth, 2 times Venus and 6 times Mercury.
This one and only near-Earth crossing at 12677 km from the surface will allow scientists to test and calibrate their instruments after 18 months in space. Eleven of the 16 instruments on the mission will be operational. Some will have their sight obstructed by the propulsion module. This is unfortunately the case with VIHI. But SORBET will be operational. Thus SORBET will make measurements in the magnetic environment of the Earth. Other BepiColombo instruments will even make some unprecedented measurements of the Moon in the ultraviolet and thermal infrared.
To know more
- The website Planète Mercure includes a follow-up of the mission, information about the planet and many educational resources..
- The site of the l’ESAwith the details of the overflight of the Earth.
- The press release for the launch of Bepi Colombo on 19 October 2018.