NASA Spacecraft Provides First View of Our Place in the Galaxy

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WASHINGTON -- NASA's Interstellar Boundary Explorer, or IBEX,
spacecraft has made it possible for scientists to construct the first
comprehensive sky map of our solar system and its location in the
Milky Way galaxy. The new view will change the way researchers view
and study the interaction between our galaxy and sun.

The sky map was produced with data that two detectors on the
spacecraft collected during six months of observations. The detectors
measured and counted particles scientists refer to as energetic
neutral atoms.

The energetic neutral atoms are created in an area of our solar system
known as the interstellar boundary region. This region is where
charged particles from the sun, called the solar wind, flow outward
far beyond the orbits of the planets and collide with material
between stars. The energetic neutral atoms travel inward toward the
sun from interstellar space at velocities ranging from 100,000 mph to
more than 2.4 million mph. This interstellar boundary emits no light
that can be collected by conventional telescopes.

The new map reveals the region that separates the nearest reaches of
our galaxy, called the local interstellar medium, from our
heliosphere -- a protective bubble that shields and protects our
solar system from most of the dangerous cosmic radiation traveling
through space.

"For the first time, we're sticking our heads out of the sun's
atmosphere and beginning to really understand our place in the
galaxy," said David J. McComas, IBEX principal investigator and
assistant vice president of the Space Science and Engineering
Division at Southwest Research Institute in San Antonio. "The IBEX
results are truly remarkable, with a narrow ribbon of bright details
or emissions not resembling any of the current theoretical models of
this region."

NASA released the sky map image Oct. 15 in conjunction with
publication of the findings in the journal Science. The IBEX data
were complemented and extended by information collected using an
imaging instrument sensor on NASA's Cassini spacecraft. Cassini has
been observing Saturn, its moons and rings since the spacecraft
entered the planet's orbit in 2004.

The IBEX sky maps also put observations from NASA's Voyager spacecraft
into context. The twin Voyager spacecraft, launched in 1977, traveled
to the outer solar system to explore Jupiter, Saturn, Uranus and
Neptune. In 2007, Voyager 2 followed Voyager 1 into the interstellar
boundary. Both spacecraft are now in the midst of this region where
the energetic neutral atoms originate. However, the IBEX results show
a ribbon of bright emissions undetected by the two Voyagers.

"The Voyagers are providing ground truth, but they're missing the most
exciting region," said Eric Christian, the IBEX deputy mission
scientist at NASA's Goddard Space Flight Center in Greenbelt, Md.
"It's like having two weather stations that miss the big storm that
runs between them."

The IBEX spacecraft was launched in October 2008. Its science
objective was to discover the nature of the interactions between the
solar wind and the interstellar medium at the edge of our solar
system. The Southwest Research Institute developed and leads the
mission with a team of national and international partners. The
spacecraft is the latest in NASA's series of low-cost, rapidly
developed Small Explorers Program. NASA's Goddard Space Flight Center
manages the program for the agency's Science Mission Directorate at
NASA Headquarters in Washington.

The Cassini-Huygens mission is a cooperative project of NASA and the
European and Italian Space Agencies. NASA's Jet Propulsion Laboratory
in Pasadena, Calif., provides overall management for Cassini and the
Voyagers for the Science Mission Directorate.

To view the sky map and for more information about IBEX, visit:

http://www.nasa.gov/ibex

For more information about other NASA science missions on the Web,
visit:

http://www.nasa.gov