Thousands of miles up, there's lots to be excited about for astrophysicist Donald Gurnett.
The instruments he's built over his 55-year career are offering new clues to the universe as the crafts they ride hurtle through space.
The Mars Express mission is poised to detect what happens to Mars' atmosphere when the planet travels through the tail of Comet Siding Spring. The Cassini spacecraft is on course to explore new regions of Saturn.
Perhaps most promising is Voyager I, which is beaming back data as it travels ever deeper into interstellar space.
But, as the University of Iowa semester winds down, Gurnett's focus is in Iowa City where he is teaching a course in fluid mechanics.
"What I am really working on hard is getting handouts ready for the next series of lectures," the 73-years-old physics and astronomy professor said.
At this stage of his career, which has essentially mirrored the lifespan of the modern-day space program, Gurnett could retire with a sense of righteousness most would admire. He has family and hobbies, and enough accomplishments and awards to fill a history book.
Instead of retiring, Gurnett works full time. He inspects new data sets in his office every day high up in Van Allen Hall, or scrawls complex physics equations across the chalkboard in his classroom.
"It's been that way for several years — I'll retire next year. It's not that I don't have other things to do, I really do," Gurnett said. "I just really like what I do."
Gurnett's made his mark studying radio waves and plasma waves, which in simple terms are magnetic fields of electrons and ions.
Among his achievements:
"He is really passionate about what he does," said Sharon Kutcher, an engineering coordinator at UI who's helped build countless space-bound instruments. "You'd never know he is 73 years old.
"He is so enthusiastic. He's a go-getter. I guess that's what keeps you young. It has for Don Gurnett."
Space research takes years to come to fruition, and Gurnett's early work still pays dividends.
Gurnett considers the recent discovery that Voyager I — launched in 1977 — had reached interstellar space one of the biggest milestone of his career. In September, NASA announced the 36-year-old Voyager had become the first manmade probe to leave the solar system and reach interstellar space (though some scientists this week have debated that claim).
Gurnett's team made the discovery through data collected from the cigar box-sized instrument they built 40 years earlier, and documented the edge of the solar system at more than 11 billion miles from Earth.
The discovery was based on a paper Gurnett published in 1993, that as it turns out, predicted the conditions of interstellar space.
"When you ask what the biggest event in my career (was), in the end this is it," Gurnett said. "You really have to be patient in this field."
The Voyager discovery gained international attention, and served as another example of Gurnett and Iowa's place in space exploration.
"He's one of the tops in the country. In plasma waves, he is the top," said Jim Green, the director of planetary science for NASA, which he said is the nation's top advocate for planetary research. "Not only has he done some of the fundamental work in the field, he just has a knack. He has an intuition."
Green credited Gurnett, who was the adviser on his master's thesis in the 1970s, with helping launch his career by pushing him into a fast-developing research area and by exposing him to top minds across the world.
While Gurnett helped bring Green into the field, James Van Allen did so for Gurnett.
Gurnett, a Fairfax native, has carried on the legacy of Van Allen, his predecessor and mentor who brought Iowa's space program to national prominence by discovering early in the space program that radiation belts surround Earth — the belts that now bear Van Allen's name.
Gurnett, who grew up with a love for aeronautics, had a part-time job working on radios at Collins Radio and had been studying engineering as a University of Iowa sophomore in 1958. He'd heard about Van Allen's research and walked into MacLean Hall to ask him for a job, and got it.
After graduation, Gurnett left for Stanford University and later returned to UI work with Van Allen as an assistant professor of physics in 1965.
Through the years, with Van Allen primarily focused on cosmic waves and Gurnett studying radio and plasma waves, the two have had instruments on NASA's biggest missions, such as Pioneer 10, Galileo, Explorer and Voyager.
Van Allen retired in 1985 and died in 2006, leaving Gurnett as the face of Iowa's space program.
Today, with federal funding for space exploration drying up and with Gurnett's career winding down, the question is what does the future hold for Iowa's historic space program.
Gurnett is no longer submitting proposals to NASA since he may be retired by the time the project starts yielding information. Members of his staff, such as research engineer Donald Kirchner, now submit research proposals through Craig Kletzing, a UI physics professor who studies the Van Allen Radiation Belts, among other areas.
"Don is that second generation genius that occurred at Iowa, that began with James Van Allen," Green said. "Who is the next generation? It is up to Iowa to recognize the greatness of that program and preserve it."
Students of Gurnett and Van Allen are all over the country, and it will be a matter of attracting bright minds back into the department, he said.
The UI physics and astronomy department has a job posting for a professor described as a "mid-career space physics experimentalist," and with the work of Kletzing, Kirchner, research scientist William Kurth, who also is a former student of Gurnett, and others, the program is in good shape, said Mary Hall Reno, a professor and the head of the physics department.
"That's totally our goal — to continue to have an active instrument building program," Reno said.