Exploration of Mercury - BepiColombo

BepiColombo

This mission to Mercury is to include two satellites: the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO). Each orbiter has a distinct purpose: the MPO is to take images of Mercury, and the MMO is to study the magnetosphere. The European Space Agency and Japan are working in conjunction on BepiColombo and will each provide one of the orbiters. The ESA will provide MPO, while Japan will provide MMO. The BepiColombo was designed with 12 specific objectives:

1. What can we learn from Mercury about the composition of the solar nebula and the formation of the planetary system?
2. Why is Mercury's normalized density markedly higher than that of all other terrestrial planets, as well as the Moon?
3. Is the core of Mercury liquid or solid?
4. Is Mercury tectonically active today?
5. Why does such a small planet possess an intrinsic magnetic field, while Venus, Mars and the Moon do not have any?
6. Why do spectroscopic observations not reveal the presence of any iron, while this element is supposedly the major constituent of Mercury?
7. Do the permanently shadowed craters of the polar regions contain sulfur or water ice?
8. What are the production mechanisms of the exosphere?
9. In the absence of any ionosphere, how does the magnetic field interact with the solar wind?
10. Is Mercury's magnetised environment characterized by features reminiscent of the aurorae, radiation belts and magnetospheric substorms observed on Earth?
11. Since the advance of Mercury's perihelion was explained in terms of space-time curvature, can we take advantage of the proximity of the Sun to test general relativity with improved accuracy?

Like Mariner 10 and MESSENGER, BepiColombo will use gravity slingshots from Venus and Earth. BepiColombo will use solar electric propulsion and then also use similar manoeuvres at the Moon, Venus, and Mercury. These techniques will slow the orbiters as they approach Mercury. It is essential to avoid using fuel to slow the orbiters as they get closer to the Sun to minimize the gravitational influence of the Sun.

BepiColombo is set for launch in August 2015. It is scheduled to enter orbit around Mercury in January 2022. It will then gather data for one, or possibly two years.