University of Iowa space legend Don Gurnett retires - sort of

'I want to live long enough to complete the Voyager mission'

University of Iowa Department of Physics and Astronomy professor Don Gurnett poses June 7 with a model of the Voyager I
University of Iowa Department of Physics and Astronomy professor Don Gurnett poses June 7 with a model of the Voyager I spacecraft in his office in Van Allen Hall in Iowa City. During his time at the UI, which started in 1957 when he was a 17-year-old undergraduate, Gurnett has worked under James Van Allen; founded and established the field of space plasma wave physics; and designed and built instruments for more than 35 space missions, including the Voyagers, Galileo, Cassini, Mars Express and Juno. (Jim Slosiarek/The Gazette

IOWA CITY — In his 62 years since starting his career first as a student and later as a professor at the University of Iowa, Don Gurnett collaborated on instruments for more than 35 space missions, participated in $600 million in research, published over 700 papers, taught 111 classes and helped found the field of space plasma wave physics.

Now the legendary astrophysicist has retired. But like some of the space missions, he keeps going.

“Why did I retire?” Gurnett mused during a recent interview, taking a reprieve from his computer where he was busy with a paper detailing his newest discoveries.

He still is going to his office

Gurnett’s last day came May 31 when he swapped his long-held “physics and astronomy professor” title for one bearing the “emeritus” label. But the following Monday, as usual, Gurnett arrived in his seventh-floor Van Allen Hall office, brimming with evidence of decades of achievements.

He ate his usual scrambled eggs and Cheerios for breakfast. He checked in with colleagues, collaborators and students. And he continued the interstellar work that’s characterized his career, digging into at least three projects he’s still multitasking, including writing up his newest findings from Voyager II.

Voyager II yields new findings

Gurnett has done extensive work with both Voyager I and II, NASA missions launched nearly 42 years ago to explore the solar system and study the planets. In 2012, Voyager I became the first human-made object to cross the threshold of interstellar space. Voyager II followed suit in November 2018.

Today, Voyager I soars about 145 astronomical units from Earth, farther than any spacecraft has traveled in human history. Voyager II, going a bit slower, is out 120 astronomical units. (Just one astronomical unit is equal to the mean distance from the center of the Earth to the center of the sun.)

For frame of reference, a radio signal — traveling at the speed of light — takes about 1 second to get from a spacecraft at the moon back to Earth.

“Right now we’re at 19 hours with Voyager I, for the radio signal to get to the Earth,” Gurnett said. “That’s one way.”

As for Voyager II, he said, it recently produced new significant confirmation of data from Voyager I, which he predicted and is writing up.


“The whole theory of how that all works has just been proven by our data 20 years ago,” Gurnett said. “I’m pretty proud of that.”

The Journal of Nature has agreed to consider Gurnett’s findings on the topic for publication, giving him a July 15 deadline.

“So I’m trying to get the paper done by July 1,” he said.

passion came early

Gurnett actually began phased retirement two years ago, even with at least eight instruments still collecting data in space. He was experiencing some minor health problems, which have since dissipated, and he continued to come to work daily.

“So why did I retire?” Gurnett asked.

With his 80th birthday on the horizon, Gurnett said he recently visited the doctor, who told him he had “TMB.”

“What’s that?” Gurnett asked, to which the doctor replied, “Too many birthdays.”

And while many folks retire to take up a hobby or travel, Gurnett said he was lucky enough to land in a field encompassing his passions and realizing his dreams — perhaps because his career started as a 10-year-old building model airplanes and working alongside Collins Radio engineers in Cedar Rapids.

“I want to give Collins Radio and the people who belong to that model airplane club a lot of credit — they were my mentors,” Gurnett said, reminiscing about testing model planes at the Cedar Rapids airport.

In the years since a 17-year-old Gurnett walked into famed UI physicist James Van Allen’s office in hopes of turning his experience in “radio-controlled electronics” into a job, which he did, the UI professor has established himself as an astronomical titan — traveling the world in the process.


“I have traveled so much in the course of doing all that,” Gurnett said, guessing he’s made some 300 trips over the Atlantic Ocean. “I have not counted the number, but it’s big.”

He’s seen the onion-shaped domes of St. Basil’s Cathedral on Red Square in Moscow. He’s visited the southern Croatian city of Dubrovnik, fronting the Adriatic Sea. And he was in Beijing just before the 1989 Tiananmen Square protests.

“I remember a dramatic thing about that,” he said of the space-science meeting he attended. “It was at a special hotel at the edge of Beijing, not downtown. And the reason was, the hotels downtown were all filled with people for a huge conference on how to set up a stock market. I knew at that point, man, China is changing.”

protege to mentor

Under Van Allen’s wing, Gurnett immediately — as a sophomore — got to work on major NASA endeavors, including the 1961 Injun I, the first spacecraft constructed entirely at a university.

And Gurnett has followed Van Allen’s example in his advising of 47 master’s and doctoral students who’ve completed 62 thesis projects.

“Why I was so successful in advising students is that I was building instruments on spacecrafts that go to brand-new places — first it was Earth’s orbit and later it was going to Jupiter and Saturn and Uranus and Neptune,” Gurnett said. “These were new things and that’s what I would assign my students to work on. I would try to pick out a project I would write myself.”

In fact, he said, “I can say I have mentored a lot of students where I wish I had had my name first on their papers.”

“When I say I wish that, well, I don’t,” he added. “I’m happy they were successful.”

He is “pushing me to excel,” says graduate student

The graduate student he’s advising — Sadie Elliott, 25, of St. Paul, Minn. — confirmed Gurnett’s report of giving students projects of import. Before even starting her classes in August 2016, Elliott was investigating plasma waves on Jupiter via an Iowa instrument on the Juno mission.

Nearly three years later, Elliott’s working on her fourth paper with Gurnett — who she said compels her pursuit of publication without being overbearing.


“He lets you do your own thing but also pushes me toward getting publication and getting my name out there,” she said, noting four papers in three years is a lot for any graduate student. “I wouldn’t have been able to do that without him pushing me.”

“I’ll probably keep coming to work,” Gurnett says

Although not much has changed since Gurnett officially retired, he has been formally replaced as Elliott’s adviser. He also joked about losing his long-held relatively close parking spot in the ramp attached to the John Pappajohn Business Building for one down the hill at the Iowa Memorial Union.

“So, why did I retire?” Gurnett asked again. “I don’t have a good answer for your question.”

Perhaps that’s because he hasn’t. Not really.

“I’ll probably keep coming to work, just like I normally do,” said Gurnett, whose future plans and goals continue to blur personal and professional boundaries — including one that would cap what he calls his proudest accomplishment.

“I want to live long enough to complete the Voyager mission.”

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