Following a smooth countdown this evening NASA’s Magnetospheric Multiscale (MMS) satellites launched aboard a ULA Altas 5. The MMS mission consists of four spacecraft, that will be deployed into orbit later this evening following the second burn of the centaur, and will then begin to deploy there various instruments to allow them to measure the interaction of the magnetic structures around the planet. The four spacecraft once fully deployed will fly in a pyramid formation allowing them to produce a 3D map of the interactions.
Each spacecraft carries identical instrument suites of plasma analyzers, energetic particle detectors, magnetometers, and electric field instruments as well as a device to prevent spacecraft charging from interfering with the highly sensitive measurements required in and around the diffusion regions.
The plasma and fields instruments will measure the ion and electron distributions and the electric and magnetic fields with unprecedentedly high (millisecond) time resolution and accuracy. These measurements will enable to MMS to locate and identify the small (1-10 km) and rapidly moving (10-100 km/s) diffusion regions, to determine their size and structure, and to discover the mechanism(s) by which the frozen-in condition is broken, the ions and electrons become demagnetized, and the magnetic field is re-configured. MMS will make the first unambiguous measurements of plasma composition at reconnection sites, while energetic particle detectors will remotely sense the regions where reconnection occurs and determine how reconnection processes produce such large numbers of energetic particles.
NASA have confirmed that the four spacecraft deployed successfully following the second burn of the centaur upper stage.
Below are screen grabs of the launch