NASA space mission dedicated to the study of magnetic reconnection events, where magnetic fields connect and disconnect with an explosive release of energy. The mission consists of four identical spacecraft with key sensors designed to measure the space environment at rates faster than any previous mission. MMS lifted off successfully on 12 March 2015 aboard an Atlas V rocket. Science operations began in September. A month later MMS made the tightest multi-spacecraft formation ever flown in orbit—flying just 6 miles apart in a four-sided pyramid pattern. By May 2016 the four MMS spacecraft had made more than 4 000 trips through the boundaries of Earth’s magnetic field, gathering observations; the data show for the first time that magnetic reconnection is dominated by the physics of electrons. In November 2016 MMS held the Guinness World Record for highest altitude GPS fix: 43 500 miles above Earth’s surface.

An artist’s concept of the Magnetospheric Multiscale Mission (MMS) to study how magnetic fields release energy in a process known as magnetic reconnection.

Credit: NASA/Goddard/Conceptual Image Lab