Trailblazer of the Week

Henry Eshbaugh

24 January 2025

Henry Eshbaugh’s favorite part of his job is—to paraphrase Lunar Trailblazer Co-Investigator Neil Bowles—“making the robot dance.” As a part-time PhD student at University of Oxford working with Bowles, Eshbaugh currently has his hands full with instruments, including one “robot” aboard Trailblazer.

Eshbaugh’s day-to-day work involves leading implementation of the flight software that operates Trailblazer’s Lunar Thermal Mapper instrument (LTM). As one of Trailblazer’s two science instruments, LTM is a multispectral imager that will measure infrared radiation emitting from the Moon’s surface. These measurements will simultaneously map the localized temperature and geologic composition of water-bearing areas on the Moon. To ensure success, Eshbaugh must multitask.

“I do everything from low-level device drivers for hardware, to higher-level operations like telecommand scheduling, to scripting ground-support equipment to operate LTM,” he says, adding that LTM’s codebase is “approximately 15,000 lines of MISRA C and about 2000 lines of Python.”

A large, high-reliability codebase operating a sophisticated instrument implies that “every design decision will lead you down many rabbit holes if you're not careful.” For Eshbaugh, this complexity management is the hardest part of the job.

“It takes intuition and experience to organize the software properly, and avoid architectural pitfalls that compromise the performance of the instrument,” says Eshbaugh. “Luckily, LTM is a very well-behaved unit!”

Previously, Eshbaugh worked for four years at the Space Magnetometer Laboratory at Imperial College London, where he contributed to the J-MAG instrument on the Jupiter Icy Moons Explorer (JUICE) spacecraft and the fluxgate on Solar Orbiter. He also handled the electronics design for the MAGIC magnetometer aboard RadCube, which launched to low-earth orbit in 2021 and is due to reenter this year. Eshbaugh recalls now how he never really considered a different career path other than engineering.

“I started learning to code quite young and was writing data structures in C by the time I was thirteen,” he says. “I decided to study electronics in college because I wanted to understand hardware better, and because I wanted to learn how to build my own guitar pedals. Joke’s on me—I play acoustic nowadays.”

Eshbaugh grew up south of Boston and attended Imperial College London where he graduated with an MEng in Electrical and Electronics Engineering. His thesis revolved around the application of modern digital signal processing to build spacefaring magnetometers.

“It was natural for me to gravitate towards embedded systems,” he says. “And spacefaring instruments are categorically the coolest embedded systems around.”

These days, he has been somewhat relieved of his magnetometer duties.

“Trailblazer is the first and only remote-sensing-only mission I've worked on,” says Eshbaugh. “Not having to worry about magnetic cleanliness requirements is a breath of fresh air.”

Looking ahead, he can’t wait to get work commissioning LTM.

“Working with the Trailblazer team has been a blast and an absolute pleasure,” says Eshbaugh. “And operating instrumentation at the Moon is inherently cool! Understanding how water works on other worlds starts with an investigation of our closest neighbor.”

Henry Eshbaugh is the LTM instrument Software Lead and Trailblazer of the Week!

Trailblazer of the Week is an ongoing series showcasing the diversity of experience and expertise that supports the collective determination of the Lunar Trailblazer mission.

By Emily Felder
Emily Felder is a Earth Science and Paleontology graduate student at UC Santa Barbara, former student at Pasadena City College, and Caltech intern working on science communication for the Lunar Trailblazer mission.