The two science orbiters (the MMO and MPO) are now connected in their launch configuration and will be loaded with propellants this week.
The image is from the process of connecting the orbiters. If you want to really have a nice detailed look ESA has a high resolution image (353k) that is really worth checking out.
About the orbiters (from ESA):
MMO (Mercury Magnetospheric Orbiter)
MMO’s main science goals are to provide a detailed study of the magnetic environment of Mercury, the interaction of the solar wind with the planet, and the diverse chemical species present in the exosphere – the planet’s extremely tenuous ‘atmosphere’.
MPO (Mercury Planetary Orbiter)
The MPO will focus more on surface processes and composition, and together with MMO, will help piece together the full picture of the interaction of the solar wind on the planet’s environment and surface. Together they will watch how this interaction at the surface feeds back into what is observed in the exosphere and how that varies both in time and location – something that can only be achieved with two spacecraft in such complementary orbits.
The mission is proceeding on a time schedule that will launch on 19 October at 01:45 UT atop an Atlas V rocket from Kourou, French Guiana.
Image credit: ESA/CNES/Arianespace/Optique video du CSG – J. Odang