The Ionospheric Occultation Experiment (IOX) was a remote sensing satellite package that used a dual frequency Global Positioning System (GPS) receiver to measure properties of the ionosphere. IOX demonstrated remote sensing techniques for future United States Department of Defense space systems and helped to improve operational models for ionospheric and thermospheric forecasts. IOX was developed by the United States Air Force Space and Missile Systems Center and was one of four experiment packages on PicoSAT, which was launched by an Athena rocket in September 2001.
Specifications NSSDC ID: 2001-043B-02 Mission: PicoSAT 9
Further reading Straus, P. R. "The Ionospheric Occultation Experiment (IOX) on PicoSat: A GPS Occultation MIssion with an Ionospheric Focus" (PDF). OPAC-1. El Segundo, California, USA: The Aerospace Corporation. Retrieved January 28, 2023. Official Abstract University Corporation for Atmospheric Research: Further Overview of IOX and GPS Receiver August 2002 Workshop Harvard University: IOX Abstract
References This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration.