Spring 2005

A Boon for Business: Incubator nurtures homegrown companies

Antibody Buildup: University lab explores Libby health issue

Space Man: New UM researcher probes the solar system for NASA

Core Issues: Flathead Lake research reveals secrets in sediment

Lords of the Prairie: Investigating the links among sage grouse, West Nile virus and energy development

About This Issue

Archive

Space Man
New UM researcher probes the solar system for NASA

Dan Reisenfeld

Dan Reisenfeld remembers signing up his second-grade classmates to be crew members on the S.S. Enterprise. He was to be captain, of course, and he meticulously assigned positions on the starship that were best suited to each second-grader’s individual skills.

Nobody suspected then that this Star Trek fantasy could lead to the real thing.

For the Cincinnati native grew up loving science, and, despite toying with becoming an architect or filmmaker, he studied physics at Yale and astronomy at Harvard. His thesis was titled “An Absolute Measurement of Resonance-resolved Electron Impact Excitation.” All this led to postdoctoral work at Los Alamos Laboratory in New Mexico, where he got into the business of designing actual NASA spacecraft and interpreting the data they produce.

He became an explorer — boldly going where no man had gone before.

Reisenfeld worked at Los Alamos during 1998-2004, meeting and marrying Maureen, a civil engineer. While he loved his work, he also realized he loved teaching. (He had taught at Harvard and the University of New Mexico.) And Maureen had this idea to start an orchard. So last year the Los Alamos staff scientist became an assistant professor with UM’s Department of Physics and Astronomy, and trees have been planted near Stevensville. Joshua Orion Reisenfeld was born in January.

Though the 38-year-old astrophysicist has left Los Alamos behind, the number of NASA probes he’s worked with has grown. Among them are:

Ulysses, a mission to study solar wind coming from the sun. Using Ulysses data, Reisenfeld had a “eureka moment” when he learned why helium streaming from the sun slows down compared to its hydrogen counterparts. He proved the helium encounters turbulence from ionized plasma gas in space, which slows it down. “That had been a mystery for 30 years,” Reisenfeld says.

• Genesis, an effort by NASA to collect solar wind particles and return them safely to Earth. Reisenfeld was one of four scientists to build the probe’s concentrator, which is similar in design to a reflecting telescope, but instead of gathering and concentrating light it concentrates solar ions. Alas, the Genesis parachute failed to open last September, allowing the probe to smash into the Utah desert at 200 mph. But Reisenfeld said three of four delicate wafers that gathered particles using the concentrator survived the impact completely intact, and the fourth is 85 percent intact. “So the highest-priority science was preserved,” he said.

• Cassini, a probe now exploring Saturn and its mysterious moon Titan, which is veiled beneath a thick atmosphere. Reisenfeld and fellow team members have learned the atmosphere of Titan is like a petroleum refinery, producing all kinds of complex hydrocarbon molecules such as methane and butane, as well as cyanide and formaldehyde. They’ve also discovered the density of water ions increases as one moves closer to Saturn and its rings, which are mostly H2O. In fact, the chemistry is similar to what is seen with comets. “Nobody knew that before,” he said.

• Deep Space 1, a probe that did a flyby of a comet in 2001. The probe was the first to use an ion engine, which constantly produces a tiny thrust to eventually build up vast velocity. “It’s 90 percent efficient, as opposed to a chemical engine that’s maybe 20 percent to 30 percent efficient,” Reisenfeld says. “But it takes a long time to build the velocity, so you have to be patient.” Since it was mainly an engineering mission, there was no funding to analyze the probe’s data. Reisenfeld was undeterred, however, and after submitting a series of proposals he recently was awarded $250,000 over the next three years to interpret the comet data.

• Interstellar Boundary Explorer or IBEX, a mission to map and study the edge of the solar system. Set to launch in 2008, the probe will study the termination shock, the region where the solar wind slows down to merge with interstellar space. Reisenfeld will help design IBEX-HI, an instrument that uses a large-aperture camera to detect high-energy particles coming from the edge of the solar system. Some of the actual instrument design will be done at UM.

Reisenfeld’s immediate plans call for teaching UM physics students and outfitting UM’s Montana Space Flight Prototype Facility, which will test designs for future NASA probes. One of his lab’s first tasks will be to bring in the spare mass spectrometer for Deep Space 1 and use it to characterize the flight instrument on the probe. (Mass spectrometers measure the atomic masses of ions that enter them.) Only then can the comet-flyby data be interpreted accurately.

“I have so much work coming up that it’s going to be a struggle to do it all,” he says, “but I plan to have several UM students come on board to help out.”

Rita Munzenrider, Director
University Relations
The University of Montana-Missoula
32 Campus Drive | Missoula, MT 59812
phone 406-243-2522 | fax 406-243-4520
© 2007 The University of Montana