Erik Shirokoff, astronomer who built instruments to map the universe, 1979-2023

Remembered as patient and generous teacher and mentor

Assoc. Prof. Erik Shirokoff, a University of Chicago astronomer who built instruments to understand the earliest ages of the universe, died Jan. 26. He was 43.

Known as a generous and patient mentor and teacher, Shirokoff was a faculty member in the Department of Astronomy and Astrophysics and a senior member of the Kavli Institute for Cosmological Physics, focusing on studying the evolution of the universe and the formation of stars and galaxies.

Born on Dec. 13, 1979 in Los Angeles, California, Shirokoff’s curiosity about the world was evident from an early age, according to friends and family. He received his undergraduate degree in physics and astrophysics in 2002 and his Ph.D. in physics in 2011, both from the University of California, Berkeley. He spent three years as a postdoctoral fellow at the California Institute of Technology before joining the University of Chicago faculty in 2014.

Shirokoff specialized in developing exquisitely sensitive detectors to pick up faint signals from the early ages of the universe. He figured out a way to build superconducting detectors into large arrays which have been used to make the most precise measurements of the Cosmic Microwave Background, the 14-billion-year-old light from the period right after the Big Bang.

Most recently, Shirokoff was working to develop a new generation of detectors to do what’s known as line intensity mapping—a burgeoning field of astronomy that promises to shed new light on the underlying distribution of matter in the universe and on the first stars and galaxies to form after the Big Bang.

“Erik was a genius with detectors,” said UChicago Prof. John Carlstrom, a colleague, collaborator and friend of Shirokoff’s for many years. “His work has already resulted in enormous amounts of new science, and his contributions to next-generation spectroscopy will help open a new window on the universe. He had a vision for the future of astronomy which we will carry forward.”

‘Incredibly creative’

Shirokoff was an integral part of the collaboration that built and runs the South Pole Telescope, which maps the leftover light from the epoch right after the Big Bang, known as the cosmic microwave background. While a graduate student, he helped produce the first generation of detectors for the telescope, persevering in the face of multiple technical setbacks to build arrays by hand. In 2009, he served as part of the two-person South Pole Station “wintering over” crew—staying at the Pole to operate the telescope through the nine-month-long Antarctic winter during which no aircraft can fly in or out.

His latest generation of detectors is scheduled to be deployed at the South Pole and at the Large Millimeter Telescope in Mexico.

“Erik was a truly exceptional experimental scientist,” said Tom Crawford, a research professor in astronomy and astrophysics at UChicago and a longtime friend and colleague. “He absolutely loved being in the lab–creating things, coming with new ideas and testing them. I think he was just genuinely very curious about how things worked, from the microscopic workings of a quantum detector all the way up to how the universe itself worked.”

“He was incredibly technically creative,” said Kirit Karkare, an associate fellow at the Kavli Institute for Cosmological Physics who worked with Shirokoff as a postdoctoral researcher for years. “His was the only group working on this technology in the country - most people thought it was too hard and didn't even try.”

Shirokoff was known in the department for his generosity and support for students; for his warmth, energy, and sense of humor; and for his passion about reforming the field of science to make it more welcoming and inclusive.

“Anytime someone needed help or advice, he would immediately put down whatever he was doing and give them his full attention for however long they needed,” said Karkare. “And he was extremely outspoken about his beliefs about what was right. He was unafraid about taking actions to address pretty serious inequities that he recognized in the world.”

Shirokoff taught and mentored hundreds of students, published more than 100 papers, and received an NSF CAREER award in 2016.

“In addition to being a highly inventive scientist pushing technological boundaries and a wizard in the laboratory, Erik was a valued member of our department—as a colleague, collaborator, mentor, teacher and friend,” said Joshua Frieman, Shirokoff’s colleague and the chair of the Department of Astronomy and Astrophysics. “We miss him.”

Shirokoff's detectors are deployed in the Tomographic Ionized Carbon Intensity Mapping Experiment (TIME) installed at the Arizona Radio Observatory in 2019, and in instruments soon to be installed in the South Pole Telescope and the Large Millimeter Telescope in Mexico. He was also working to develop detectors for future NASA space-based observatories.

Outside of his research, Shirokoff was particularly passionate about music, educational outreach, and social justice, among other interests. Friends, family, and colleagues said he applied the same fervor to whatever he was doing—whether traveling across Siberia by train and foot, attending demonstrations and protests, experimenting with audio and new musical instruments, or participating in Situationist-inspired events in San Francisco.

Shirokoff died of complications resulting from a fall. He is survived by his spouse Alanna S. Radlo-Dzur, his parents Leah Shirokoff, Terry Shirokoff and their partners, and his childhood mentor Dennis Ghiatis; and is mourned by a wide community of friends and colleagues around the globe.