SwRI-Led Interstellar Boundary Explorer (IBEX) Mission Enters Implementation Phase.

SAN ANTONIO -- Just as the Voyager 2 spacecraft is approaching the edge of our solar system, Southwest Research Institute received official confirmation from NASA Headquarters to proceed into the mission implementation phase for the Interstellar Boundary Explorer (IBEX) mission. IBEX, which will provide global images of the interstellar boundary, the region between our solar system and interstellar space, is scheduled to launch in June 2008.

"We are most honored to be confirmed at a time when NASA's science program is under such intense budgetary pressure," says Principal Investigator Dr. David J. McComas, who also serves as senior executive director of the SwRI Space Science and Engineering Division. "This tremendous support really shows the importance of the IBEX science mission.

"IBEX will let us visualize our home in the galaxy and imagine how it may have evolved over the history of the solar system," McComas continued. In mid-2008, the IBEX mission will launch a pair of energetic neutral atom (ENA) "cameras" to image the interaction between the solar system and the low-density material between the stars. The Sun's hot outer atmosphere continuously evaporates into space, forming the million-mile-per-hour solar wind that creates a protective envelope around our solar system, far beyond the most distant planets. IBEX will image our solar system's previously invisible outer boundaries to discover how the solar wind interacts with the galactic medium.

"Everything we think we know about this region is from models, indirect observations and the recent single-point observations from Voyagers 1 and 2 that frankly have created as many questions as answers," says McComas. Voyager 2 may be approaching the termination shock, the outermost layer of our solar system, even sooner than expected based on when Voyager 1 crossed the region. Data suggest that the edge of the shock could be one billion miles closer to the sun in the southern region of the solar system than in the north, suggesting perhaps that the heliosphere is irregularly shaped.

"The extensive global data IBEX will collect, used in concert with the local data that the Voyager missions are sampling, will provide a much deeper understanding of the Sun's interaction with the galaxy," McComas added. "In addition to revealing many of the interstellar boundary's unknown properties, IBEX will explore how the solar wind regulates the galactic cosmic radiation from the galaxy. This radiation poses a major hazard to human space exploration of the solar system."

SwRI is partnering with Orbital Science Corporation, Los Alamos National Laboratory, Lockheed Martin Advanced Technology Center, Goddard Space Flight Center, the University of New Hampshire, the University of Bern and the Johns Hopkins University Applied Physics Laboratory. In addition, the team includes a number of U.S. and international scientists from universities and other institutions, as well as the Adler Planetarium, which is leading education and public outreach for the mission. IBEX is a NASA Explorer Program mission.

As the Southwest Research Institute-led Interstellar Boundary Explorer mission enters the implementation phase, the spacecraft and instrument designs are being completed, and prototype hardware is being built and tested. The University of Bern built these electrostatic analyzer plates to bend particle trajectories, enabling very low-background observations of the edge of our solar system.

EDITORS: More information about the IBEX mission is available from the IBEX website at http://www.ibex.swri.edu.

SwRI is an independent, nonprofit, applied research and development organization based in San Antonio, Texas, with more than 3,000 employees and an annual research volume of more than $435 million. Southwest Research Institute and SwRI are registered marks in the U.S. Patent and Trademark Office. For more information about Southwest Research Institute, please visit newsroom.swri.org or www.swri.org.