Radiation Belt Processes in a Declining Solar Cycle

An artist’s rendering of the twin Van Allen Probes observatories with fully deployed instruments trailing each other along a geocentric orbit (an ellipse measuring 1.1 × 5.8 Earth radii), cutting through the inner magnetosphere. Over the extended mission, the probes will quantify the processes governing Earth’s radiation belt and ring current environment as the solar cycle transitions from solar maximum through the declining phase.

An artist’s rendering of the twin Van Allen Probes observatories with fully deployed instruments trailing each other along a geocentric orbit (an ellipse measuring 1.1 × 5.8 Earth radii), cutting through the inner magnetosphere. Over the extended mission, the probes will quantify the processes governing Earth’s radiation belt and ring current environment as the solar cycle transitions from solar maximum through the declining phase.

The Van Allen Probes began an extended mission in November to advance understanding of Earth’s radiation belts.

The morning of 30 August 2012 saw an Atlas 5 rocket launch of the twin Radiation Belt Storm Probes, the second spacecraft mission in NASA’s Living with a Star program. The probes settled into an elliptic orbit that cut through Earth’s radiation belts, home to highly variable populations of energetic particles dangerous to astronauts’ health and spacecraft operation. Renamed the Van Allen Probes soon after launch, the spacecraft are equipped with instruments designed to determine how these high-energy particles form, respond to solar variations, and evolve in space environments.

During their prime mission, the Van Allen Probes verified and quantified previously suggested energization processes, discovered new energization mechanisms, revealed the critical importance of dynamic plasma injections into the innermost magnetosphere, and used uniquely capable instruments to unveil inner radiation belt features that were all but invisible to previous sensors.

Now, through an extended mission that began 1 November 2015, the Van Allen Probes will advance understanding of the dynamics of near-Earth particle radiation. The overarching objective of this extended mission is to quantify the mechanisms governing Earth’s radiation belt and ring currentenvironment as the solar cycle transitions from solar maximum through the declining phase.

The complete article thanks to EOS magazine, here: