On August 31, 2012, NASA's Magnetospheric Multiscale (MMS) mission proved it was ready for its next steps by passing what's called a Systems Integration Review (SIR), which deems a mission ready to integrate instruments onto the spacecraft.
The MMS mission is due to launch in late 2014. It will observe a mysterious process called magnetic reconnection, which creates explosive bursts of energy and which powers a variety of space phenomena from the aurora to giant eruptions of radiation on the sun known as solar flares.
The spacecraft have been under construction, a process made all the more complex since MMS requires the building of four identical spacecraft.
The Magnetospheric Multiscale (MMS) mission is a Solar Terrestrial Probes mission comprising four identically instrumented spacecraft that will use Earth's magnetosphere as a laboratory to study the microphysics of three fundamental plasma processes: magnetic reconnection, energetic particle acceleration, and turbulence. These processes occur in all astrophysical plasma systems but can be studied in situ only in our solar system and most efficiently only in Earth's magnetosphere, where they control the dynamics of the geospace environment and play an important role in the processes known as "space weather."
For more information about NASA's MMS mission, go to: http://mms.gsfc.nasa.gov/