San Antonio — January 27, 2005 — NASA has chosen Southwest Research
Institute (SwRI) to lead the first mission to image the outer boundaries of
the solar system, the region separating our solar system from interstellar
space. The Interstellar Boundary Explorer (IBEX) is NASA’s next Small
Explorer. The Explorer Program develops low-cost, rapidly developed space
science investigations.

“IBEX will make the first images of the interstellar boundaries beyond our
solar system, thereby providing a first step to exploring the galactic
frontier,” says Principal Investigator Dr. David J. McComas, senior
executive director of the SwRI Space Science and Engineering Division. The
IBEX spacecraft carries a pair of energetic neutral atom (ENA) “cameras” to
image interactions between the solar wind blown out by the Sun and the
low-density material between the stars – interactions never before observed
directly. “This mission will provide a much deeper understanding of the
Sun’s interaction with the galaxy and will also address a serious challenge
facing manned exploration by studying the region that shields us from the
majority of galactic cosmic ray radiation,” McComas adds.

The Sun’s hot outer atmosphere continuously evaporates into space, forming
the million-mile-per-hour solar wind that creates a protective envelope
around the solar system, far beyond the most distant planets. IBEX will
image the solar system’s previously invisible outer boundaries to discover
how the solar wind interacts with the galactic medium.

“In addition to revealing many of the interstellar boundary’s unknown
properties, IBEX will explore how the solar wind regulates the radiation
from the galaxy,” says McComas. “This radiation poses a major hazard to
human space exploration and may have affected the formation and evolution of
life on Earth. By examining the underlying physics of our solar system’s
outer boundaries, IBEX will allow us to extrapolate the present day
conditions to those of the past and the future, and offer insight into
similar boundaries that surround other stars and stellar systems.”

To achieve this important mission, SwRI and its partners are developing a
small, lightweight spacecraft to launch from a Pegasus rocket dropped from
an airplane. The spacecraft will attain a highly elliptical orbit that
reaches 150 thousand miles above the Earth.

The IBEX payload consists of two imagers designed to detect neutral atoms
from the solar system’s outer boundaries and galactic medium. For IBEX, SwRI
is partnering with Orbital Science Corporation, Los Alamos National
Laboratory, Lockheed Martin Advanced Technology Center, NASA Goddard Space
Flight Center, the University of New Hampshire and the Applied Physics
Laboratory. The team also includes a number of U.S. and international
scientists from universities and other institutions, as well as Chicago’s
Adler Planetarium, which is leading education and public outreach for the

IBEX is expected to cost approximately $134 million and is slated to launch
around 2008. It will return global images of the interstellar interaction by
the end of the decade.

NASA’s Goddard Space Flight Center manages the Explorer Program for the
Science Mission Directorate.

Editors: More information about the IBEX mission is available from the IBEX
web site at

SwRI is an independent, nonprofit, applied research and development
organization based in San Antonio, with more than 2,800 employees and an
annual research volume of more than $399 million.