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"We've been good at measuring charged particles, but it's a challenge for a camera to measure a neutral atom," Mšbius says. "Essentially, we're building Geordi's visor," he jokes, referring to the blind Star Trek character Geordi La Forge whose futuristic sunglasses allow him to see better than his fellow shipmates.

As the solar system moves through our galaxy, it encounters something called the interstellar medium: In it are particles released both by the explosions of novas and supernovas and the stellar winds from other stars. Our solar system travels through space in a huge magnetic bubble called the heliosphere, which serves as Earth's first line of defense from dangerous cosmic rays (the other two are the Earth's magnetic field and its atmosphere). Launched in 2008, the satellite will travel in a highly elliptical orbit that will allow it to produce the first map of the heliosphere's boundary; it will also capture neutral interstellar gas. "Now we will be getting at the real thing," says Mšbius. "We want to study the raw material out of which stars and planets are formed. It's the only place we can get our hands directly on this interstellar gas."

Beepers, Balloons and Contraband

So many graduate students have worked with astrophysicist Jim Ryan on his gamma ray and cosmic ray projects that he has a shelf full of their black hard-bound theses. The Compton Gamma Ray Observatory, launched in 1991 with four UNH-built instruments aboard, orbited Earth 51,658 times and sent back many dissertations' worth of data before NASA decided five years ago to crash the observatory, after one of its gyroscopes failed, in a remote part of the Pacific Ocean.

For those nine years, Ryan kept a beeper either on his belt or next to his bed to alert him when the observatory detected a cosmic gamma ray burst. When his beeper went off, Ryan would rush to the phone to alert astronomers before the burst disappeared. "There would be one every two to three weeks, and always in the middle of the night," says Ryan, laughing.

There are two sources of gamma ray bursts, according to Ryan. One is hypernovas, clusters of incredibly massive stars that emit an enormous burst of radiation when they die. The other is thought to come from collisions between neutron stars, which are stars that have collapsed under their own weight.

Ryan is now working on several new projects, including Groundwinds, a close-to-Earth mission that will study how wind travels in the first 15 to 18 miles of our atmosphere. Using huge balloons, the experiment will illuminate small patches of the atmosphere with short bursts of a laser, allowing telescopes on the ground to get a snapshot of the wind's speed by observing a change in color called the Doppler effect. "Our lack of knowledge of the wind on a global scale is a big limiting factor in our ability to predict weather," he says.

A neutron camera that Ryan is building for a future NASA mission turns out to have an unanticipated application for homeland security. Under a three-year, $750,000 grant from the U.S. Department of Energy, Ryan and his team are re-engineering their space-based instrument to detect contraband radioactive material at train stations, truck stops, ports and border crossings. "The neutrons coming from radioactive, fissionable material—plutonium, uranium—are all right smack in the same energy range as those we're looking to detect close to the Sun," he says. And, to locate radioactive contraband, he adds, "what you need is a sensitive, small, lightweight, low-power detector, which is just what we've been working on for the past year and a half."

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