The Van Allen Probes, formerly known as the Radiation Belt Storm Probes (RBSP), were two robotic spacecraft that were used to study the Van Allen radiation belts that surround Earth. NASA conducted the Van Allen Probes mission as part of the Living With a Star program. Understanding the radiation belt environment and its variability has practical applications in the areas of spacecraft operations, spacecraft system design, mission planning and astronaut safety. The probes were launched on 30 August 2012 and operated for seven years. Both spacecraft were deactivated in 2019 when they ran out of fuel. They are expected to deorbit during the 2030s. Overview NASA's Goddard Space Flight Center manages the overall Living With a Star program of which RBSP is a project, along with Solar Dynamics Observatory (SDO). The Johns Hopkins University Applied Physics Laboratory (APL) was responsible for the overall implementation and instrument management for RBSP. The primary mission was scheduled to last 2 years, with expendables expected to last for 4 years. The primary mission was planned to last only 2 years because there was great concern as to whether the satellite's electronics would survive the hostile radiation environment in the radiation belts for a long period of time. When after 7 years the mission ended, it was not because of electronics failure but because of running out of fuel. This proved the resiliency of the spacecraft's electronics. The spacecraft's longevity in the radiation belts was considered a record-breaking performance for satellites in terms of radiation resiliency. The spacecraft worked in close collaboration with the Balloon Array for RBSP Relativistic Electron Losses (BARREL), which can measure particles that break out of the belts and make it all the way to Earth's atmosphere. The Applied Physics Laboratory managed, built, and operated the Van Allen Probes for NASA. The probes are named after James Van Allen, the discoverer of the radiation belts they studied. Milestones Mission concept review completed, 30–31 January 2007 Preliminary design review, October 2008 Confirmation review, January 2009 Probes transported from Applied Physics Laboratory in Laurel, Maryland to Cape Canaveral Air Force Station in Florida, 30 April 2012 Probes launched from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida on 30 August 2012. Liftoff occurred at 4:05 a.m. EDT. Van Allen Probe B deactivated, 19 July 2019. Van Allen Probe A deactivated, 18 October 2019. End of mission. Launch vehicle On