The Interstellar Boundary Explorer (IBEX) mission

The Interstellar Boundary Explorer (IBEX) is scheduled to launch in June 2008 to make the first global observations of the heliosphere's interaction with the interstellar medium. IBEX achieves these breakthrough observations by traveling outside of the Earth's magnetosphere in a highly elliptical, high-apogee orbit and taking global Energetic Neutral Atoms (ENA) images over energies from ∼10 eV to 6 keV. IBEX's orbit enables heliospheric ENA measurements by providing viewing from outside the earth's relatively bright magnetospheric ENA emissions, and is achieved by adding an IBEX-supplied solid rocket motor on top of a standard Pegasus launch vehicle. IBEX carries two very large-aperture, single-pixel ENA cameras that view perpendicular to the spacecraft's sun-pointed spin axis. Over the course of each six months, the spacecraft spin and progression of the sun-pointing spin axis in inertial space naturally lead to global, all-sky images. McComas et al. (2004) described the IBEX science background, requirements, and measurement strategies; here we summarize IBEX's measurement approach and mission. Additional information on IBEX is also available at www.ibex.swri.edu.