NASA’s Interstellar Boundary Explorer (IBEX) is fully operational after the mission team successfully reset the spacecraft on March 2.
Back on February 18, IBEX experienced a flight computer reset during a planned contact and the spacecraft went into contingency mode. While fight computer resets have happened before, this time the team lost the ability to command the spacecraft during the subsequent reset recovery. The team also was unsuccessful in regaining command capability by resetting ground systems hardware and software.
Flight software still was running, and the spacecraft systems appeared to be functional. However, while uplink signals are reaching the spacecraft, commands were not processing.
To take the spacecraft out of contingency mode, the mission team performed a firecode reset (which is an external reset of the spacecraft) instead of waiting for the spacecraft to perform an autonomous reset and power cycle on March 4. The decision took advantage of a favorable communications environment around IBEX’s perigee – the point in the spacecraft’s orbit where it is closest to Earth.
After the firecode reset, command capability was restored. IBEX telemetry shows that the spacecraft is fully operational and functioning normally.
Launched on October 19, 2008, IBEX is a space mission designed to study the interaction between the solar wind and the interstellar medium, which is the gas, dust, and cosmic rays that exist in the space between stars. IBEX, a spacecraft about the size of a bus tire, uses a suite of instruments to measure energetic neutral atoms that are created at the boundary between the solar wind and the interstellar medium. These measurements help scientists better understand the structure and dynamics of the heliosphere, which is the region of space that is influenced by the solar wind. IBEX has made important discoveries about the nature of the interstellar medium and the heliosphere.