Radio Aurora Explorer (RAX) is the first National Science Foundation sponsored CubeSat mission. The RAX mission is a joint effort between SRI International in Menlo Park, California and the University of Michigan in Ann Arbor, Michigan. The chief scientist at SRI International, Dr. Hasan Bahcivan, led his team at SRI to develop the payload while the chief engineer, Dr. James Cutler, led a team of students to develop the satellite bus in the Michigan Exploration Laboratory. There are currently two satellites in the RAX mission.
RAX (Radio Aurora Explorer) is a student-built nanosatellite for ionospheric research. It is built on a triple CubeSat structure. RAX measures the energy flow in the ionosphere, the highest part of Earth's atmosphere where solar radiation turns regular atoms into charged particles.
RAX is a Ground-to-Space Bistatic Radar Experiment. The RAX satellite acts as a receiver that picks up signals from a ground radar transmitter. These radar pulses reflect off disturbances, or space weather phenomena, in the ionosphere.
RAX 1 was launched in 2010 as a piggy-back payload on a Minotaur-4 HAPS launch vehicle. It suffered from an anomaly on the solar panels, which resulted in degradation of power generation until, after several months, RAX-1 was unable to generate power. This anomaly ultimately resulted in the premature end of the mission. Despite this early end, the RAX-1 mission still made great strides in CubeSat design, and was able to execute bistatic radar measurements that had never before been performed with a CubeSat. All other subsystems also performed well.
The team applied the lessons learned from RAX-1 to the design of a second flight unit, RAX-2, which was launched on a Delta-7920-10C through the NASA Educational Launch of Nanosatellites (ELaNa) program in October 2011. CubeSat separation occurred 98 minutes after launch, and beacons from RAX-2 were heard shortly thereafter.
Facts in Brief
Launch Date: 2011-10-28
Launch Vehicle: Delta II 7920
Launch Site: Vandenberg AFB, United States