February 24, 2015 – The United Launch Alliance Atlas V rocket that will send NASA’s Magnetospheric Multiscale spacecraft into orbit is nearly fully assembled at Cape Canaveral Air Force Station’s Space Launch Complex 41.
The rocket’s first stage was installed February 6 and its two solid rocket boosters were added February 7 and February 9. The Centaur upper stage arrived at the launch complex on February 12 and was lifted into place atop the first stage.
Meanwhile, the four observatories comprising the MMS spacecraft continued their prelaunch preparations at the Astrotech Payload Processing Facility. Engineers cleaned and inspected the spacecraft’s science instruments and 32 GPS antennas, and the lower two observatories were attached to the Atlas V payload adapter. The upper two observatories then were hoisted and mated to the lower stack.
The payload fairing that will protect MMS during launch was secured around the spacecraft yesterday in advance of the overnight journey from Astrotech to the launch complex, scheduled for Thursday morning.
The MMS mission is a Solar Terrestrial Probes mission consisting of four identical spacecraft that will orbit around Earth through the dynamic magnetic system surrounding our planet, making three-dimensional measurements of its magnetosphere. The purpose of the mission is to study the microphysics of three fundamental plasma processes: magnetic reconnection, energetic particle acceleration, and turbulence.
The four identically instrumented MMS spacecraft fly in an adjustable pyramid-like formation that enables them to observe the three-dimensional structure of magnetic reconnection. This enables them to determine whether reconnection occur in an isolated locale, everywhere within a larger region at once, or traveling across space.
MMS sensors will measure charged particle velocities, as well as electric and magnetic fields, with unprecedented (milliseconds) time resolution and accuracy needed to capture the elusively thin and fast-moving electron diffusion region. MMS probes reconnection of solar and terrestrial magnetic fields in the dayside and nightside of Earth’s magnetosphere, the only natural laboratory where it can be directly observed by spacecraft.
By studying how reconnection occurs near Earth, MMS will improve our understanding of how this fundamental process works elsewhere in the universe. Magnetic reconnection also occurs on the sun and is the driver of solar flares and massive eruptions of a material called coronal mass ejections. Scientists have also theorized that magnetic reconnection may be involved with a variety of astrophysical phenomena including how high-energy cosmic rays are accelerated so fast.
Understanding reconnection could even provide clues to developing a new source of efficient, clean, sustainable energy here on Earth, as magnetic reconnection can interfere with the success of fusion energy reactors.
Each MMS observatory is in the shape of an octagon, roughly 11 feet across and 4 feet high, and built around a central cylindrical thrust tube. The majority of the science instruments and associated electronics are mounted on the underside of the top deck. The flight control hardware in installed on the upper side of the bottom deck. Each observatory is also equipped with six long electric antennas with science sensors on the end as part of the science experiments. Primary power is supplied by eight solar array panels, with a secondary battery for energy storage and use during eclipses.
The Laboratory for Atmospheric and Space Physics (LASP) in Boulder is hosting the MMS Science Operations Center (SOC), which includes science operations planning, instrument command sequence development, and science analysis support.
Additionally, science data for all MMS measurements will be hosted at LASP and centrally disseminated to the science community. LASP Director, Dan Baker, is leading the SMART (Solving Magnetospheric Acceleration, Reconnection, and Turbulence) Science Operations Center, and LASP built several key components to the MMS FIELDS investigation instruments.
The MMS satellites are currently scheduled to launch atop a United Launch Alliance Atlas V rocket from Cape Canaveral, Florida on March 12, 2015.