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Artist's depiction of New Horizons flying past Pluto with its moon Charon behind it. (Credit: NASA)

In spring 2002, Chelsey Bryant Krug flew to Colorado in search of a job.

She had just enrolled as a graduate student in aerospace engineering sciences at the 91��Ƭ������AV. She found the office of Michael McGrath, then the director of engineering at the highly regarded (LASP) at CU Boulder. He wasn’t in, so Krug left her contact info on a sheet of bright pink paper.

“He told me later that he never would have seen the note if I hadn’t used that pink paper,” Krug said.

She didn’t know it at the time, but that pink note would shape the rest of Krug’s career. It would also send the engineer, or at least her handiwork, more than 5.5 billion miles from Earth.

From 2002 to 2004, Krug joined the all-student team that developed the , a scientific instrument riding on ��������’s spacecraft. The instrument, which has since traveled to the edge of the solar system, collects and analyzes tiny grains of dust flying through space. These grains hold vital clues to understanding this dark and mysterious part of space, and the forces that shaped Earth and neighboring planets billions of years ago.

To date, the Student Dust Counter (SDC) remains ��������’s only planetary science instrument designed and built almost entirely by students. Students still operate the instrument today.

They’re celebrating a big milestone: On July 14, 2015, New Horizons completed its now-famous flyby of Pluto, capturing images of the dwarf planet in astonishing detail. To mark the 10th anniversary of the event, Krug and other current and former LASP students are reflecting on their experiences.

“What an amazing opportunity,” said Krug, who still works at LASP as the institute’s aerospace engineering production manager. “I got to touch and build the flight hardware. That doesn’t happen often.”

Over the years, more than 30 undergraduate and graduate students have worked on the Student Dust Counter. They designed its electronics, assembled its 14 dust detectors, and even managed its budget. Many of these researchers have gone on to become leading professionals at NASA, universities and aerospace companies across the country.

This historic image of Pluto from 2015 reveals a heart-shaped plain on the dwarf planet's surface known as Tombaugh Regio. (Credit: NASA)

The Student Dust Counter was named for Venetia Burney Phair, who, in 1930 at 11-years-old, suggested the name for the newly discovered Pluto. Mihály Horányi met Phair in 2006. (Credit: LASP)

It's a testament to LASP’s legacy of training the country’s next generation of space scientists and engineers, said physicist Mihály Horányi. He has served as the instrument’s principal investigator for more than two decades, overseeing the student teams that worked on the dust counter.

“These students were assigned to something unimaginable,” said Horányi, professor of physics and a LASP researcher. “This instrument has traveled more than 60 times farther from the sun than Earth, and students are in charge of making it work.”

Earth’s sandbox

Jamey Szalay was one of those students in charge of making the dust counter work. From 2011 to 2015, he served as the student lead for the instrument, the third in a series of eight graduate students who have held that title at LASP.

He also sat in an operations room at the Johns Hopkins University Applied Physics Laboratory (APL) in Maryland when the mission sent home its first images of Pluto. The mission is led by Alan Stern at the in Boulder, Colorado, and managed by NASA and APL.

“We were delightfully surprised at how complicated Pluto was,” said Szalay, now a research scholar at Princeton University. “It has wonderfully diverse terrain.”

Tiny grains of dust, many too small to see with the naked eye, pervade the solar system. These grains of dust open a window to an epoch in the history of our cosmic neighborhood billions of years ago. At the time, a giant disk of dust rich in elements like carbon and silicon circled our young sun. Over time, that matter condensed to form planetary bodies like Earth and Pluto. But to study what’s left of the dust, scientists have to collect these particles directly.

“There’s still a lot that we can learn about our own sandbox, our own solar system’s dust disk,” Szalay said. “The SDC is the only dust instrument that has ever measured the outer reaches of our solar system.”

After soaring by Pluto in 2015, the spacecraft pressed deeper into a region of the solar system known as the Kuiper Belt. This expanse of space is home to icy objects like Arrokoth, a snowman-shaped world that is about 19 miles tall.

Drawing on data from the Student Dust Counter, Szalay, Horányi and colleagues discovered that the Kuiper Belt contains several times more dust than scientists predicted. One theory suggests that these grains of dust may be made of different materials than expected.

“Not a lot of folks get to work on space instrumentation in general. Those that do often have to wait until much later in their career,” Szalay said. “To have that hands-on capability in grad school was an electric jump-start to my career.”

����Students at work

The Student Dust Counter team poses for a photo in 2003. (Credit: LASP)

Students pose with the Student Dust Counter instrument in a clean room. (Credit: LASP)

Chelsey Krug works on tests of the Student Dust Counter at a dust accelerator in Heidelberg, Germany, in 2003. (Credit: LASP)

LASP students Jamey Szalay, left, and Marcus Piquette, right, give interviews to the media during the encounter with Pluto in 2015. (Credit: LASP)

In 2015, current and former LASP students along with Alan Stern, second from left, and Mihály Horányi, middle, flash the number nine for Pluto. (Credit: LASP)

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Technicians add a plate bearing the Ralphie logo onto the IDEX instrument. (Credit: Glenn Asakawa/CU Boulder)

����LASP’s dusty legacy

The Student Dust Counter was the first instrument LASP built to collect dust in space, but it wasn’t the last. Learn about the instruments that followed in its footsteps.

CDE was one of three instruments aboard the (AIM) spacecraft, which launched in 2007 and operated until 2023. The instrument monitored how dust from space entered Earth's atmosphere.

LDEX sat on the (LADEE) spacecraft, which intentionally crashed into Earth's moon in 2014. The instrument studied dust in the moon’s extremely thin atmosphere.

��������’s mission launched for Jupiter’s icy moon Europa in 2024 and will arrive in 2031. The spacecraft carries the bucket-shaped SUDA, which will analyze the contents of icy particles soaring above the moon’s surface.

IDEX is set to launch in 2025 aboard the . The instrument will collect stardust, or the particles entering Earth’s solar system from the galaxy beyond.

Cold space

To make those kinds of jump starts a reality, Krug and the other students who built the Student Dust Counter had to get creative.

The instrument, which is about the size of a large briefcase, sits on the front of the spacecraft and includes 14 detectors about the size of a dollar bill. Each detector is made up of a metal base coated in the same material used in kitchen Saran Wrap. Every time a tiny grain of dust pings one of the detectors, the device releases a small electric current.

Horányi added that NASA didn’t go easy on the student team. Krug and her colleagues had to meet the same standards and testing requirements as with any other space instrument. The students, for example, wanted to be sure their detectors could survive in the frigid stretches of space beyond Pluto. To do that, they dunked their designs directly into liquid nitrogen.

“The instrument works as well today as it did on day one, almost 20 years after launch,” Horányi said.

In her current role at LASP, Krug works with CU Boulder’s latest crop of undergraduate and graduate students. She tries to pass on the lessons she learned from the Student Dust Counter.

“I always tell students to find a research opportunity, even if it’s just helping a professor with data entry,” she said. “You have to build up your resume to be considered for jobs in the future.”

Late-night calls

Alex Doner, a graduate student in physics at CU Boulder, is the eighth lead for the Student Dust Counter and is currently training his successor.

The job comes with a lot of sleepless nights. In his role, Doner sends the instrument commands, makes sure it’s working as expected, and downloads and analyzes its data about once a month. If anything goes wrong, he’s the first person NASA calls.

It’s an experience few graduate students ever get.

“We’re not just managing an experiment and writing a paper,” Doner said. “It’s learning a complex scientific system, mastering it, making it our own and then teaching it to another graduate student. It’s a whole life cycle of science.”

Blair Schulze, a graduate student in physics who will take over from Doner next year, sees her experiences on the dust counter setting her up for success in her future career.

“Learning these skills as a student is a huge advantage after graduation when going into any future career in spacecraft or space sciences,” she said.

The current and former students emphasize that, while students led the project, the Student Dust Counter wouldn’t be possible without Horányi’s patient teaching and leadership.

Doner added that one of his favorite parts of the job comes up during his regular calls with the New Horizons team. At the end of the call, the groups overseeing the spacecraft’s five scientific instruments confirm that their equipment is functioning as it should. For the graduate student, it still feels like something out of a Hollywood space movie.

“Every instrument says it’s a ‘go’ or a ‘no-go.’ I get to say ‘SDC is go’ every two weeks,” Doner said. “It’s always just a little bit inspiring.”