Unbuckling the belts

The Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, will develop and operate twin NASA spacecraft to study how the sun interacts with Earth’s radiation belts.

Part of NASA’s Living With a Star Program, the Radiation Belt Storm Probes (RBSP) mission will determine how varying inputs of solar energy form or change populations of relativistic electrons and ions in the Earth’s radiation belts, the bands of charged particles trapped by Earth’s magnetic field that extend 20,000 miles around Earth.

After launch, scheduled for 2012, the RBSP spacecraft will measure the distributions of charged particles as well as the electric and magnetic fields that energise, transport or remove the particles within these belts.

Detailed design of the probes will begin this summer, after NASA selects the spacecraft’s science instruments.

According to a statement, the mission’s science results will provide the understanding needed to predict potentially hazardous space weather effects. Furthermore, observations from the spacecraft will be used to improve the characterisation of planetary space environments. Increased knowledge of the space environment and effects of space weather will permit better design and operations of new technology on Earth and in space.

“For the first time, several spacecraft will simultaneously watch activity on the sun and the reaction to that activity within Earth’s radiation belts,” said Ken Potocki, APL’s Living With a Star programs manager. “These probes will have to work in an incredibly difficult radiation environment where charging and discharging will occur, a lot like flying into an electrical storm. But our team looks forward to the engineering and design challenge. We know how important these data will be.”

Radiation Belt Storm Probes is the first project assigned to APL under a 12-year contract, awarded in December 2000, to design, develop and operate missions in the Living With a Star and Solar Terrestrial Probes programs.

The Lab’s experience in developing spacecraft to study the sun-Earth relationship includes the TIMED satellite, currently examining solar effects on Earth’s upper atmosphere, and the twin STEREO probes, which after launch this summer will begin taking the first 3D images of solar events called coronal mass ejections, which can blast billions of tons of the sun’s atmosphere into space and trigger severe magnetic storms when they collide with Earth.