MESSENGER successfully flew by Mercury on September 29, 2009, gaining a critical gravity assist that will enable it to enter orbit about Mercury in 2011.
This mission to Mercury has been given full approval as an ESA cornerstone mission. The mission as now envisioned will consist of two modules. The Mercury Planetary Orbiter (MPO) will perform global remote sensing and radio science investigations. The Mercury Magnetospheric Orbiter (MMO) will carry the field, wave, and particle instruments in an eccentric orbit around Mercury.