An example of a galaxy observed across the electromagnetic spectrum through three different telescopes to achieve a detailed view of a galaxy. Credit: Courtesy of Adam Leroy

An example of a galaxy observed across the electromagnetic spectrum through three different telescopes to achieve a detailed view of a galaxy. Credit: Courtesy of Adam Leroy

Ohio State astronomy professor Adam Leroy is the 2025 recipient of the Henry Draper Medal. 

The Henry Draper Medal, established in 1886, is awarded every four years to a researcher or pair of researchers who make significant advancements in astronomical physics, according to the National Academy of Sciences website. 

Leroy said he received the medal for his work in and studies of the interstellar medium — the material made up of gas and dust between galaxies — and its role in star formation in nearby galaxies. Using advanced technology, he has created multi-wavelength surveys and datasets that help researchers better understand cosmic origins.

“If you want to imagine where the next generation of stars or planets are coming from, they’re forming out of this material,” Leroy said.

Interstellar medium is the material behind galaxies’ wonders and visual appeal, Leroy said.

“When you take a picture of a galaxy, you see these beautiful spiral arms and a sprinkling of diamonds across a background sea of older stars,” Leroy said. “That’s all gas and dust forming stars.”

Leroy has played a leading role in the PHANGS — or Physics at High Angular Resolution in Nearby Galaxies — project, which leverages the world’s most advanced telescopes — including NASA’s James Webb Space Telescope, the Hubble Space Telescope and the Atacama Large Millimeter/submillimeter Array in the Chilean Andes — to conduct detailed surveys of nearby galaxies, according to the National Academy of Sciences’ website.

The project has been a collaborative effort, involving a global network of 150 scientists, according to the University of Oxford Department of Physics website.

Leroy said the striking details of these visual surveys not only showcase the structure of galaxies but also the interstellar medium’s role in star formation.

“This is completely insane; one of our pictures has shown up on a postage stamp in the last couple of weeks, which is nuts,” Leroy said. 

Leroy said for a long time, astronomers studied individual star-forming clouds one at a time, moving from place to place. However, because of technological advances — notably, the ALMA telescope — researchers can now study stellar nurseries with a larger scope. 

This research has allowed scientists to map the locations and properties of approximately 100,000 stellar nurseries, providing new insights into star formations in the closest 100 galaxies, according to the National Academy of Sciences.

Todd Thompson, the Allan H. Markowitz Endowed Chair in Astronomy at Ohio State, said Leroy’s contributions to the field are important and widespread.

“Adam’s always been a leading figure in gathering new, state-of-the-art data on all kinds of galaxies and their star formation,” Thompson said. “He has an incredible ability to bring in spectacular new datasets.”

Thompson said his colleagues in the Department of Astronomy, Laura Lopez and Smita Mathur, are working to incorporate X-rays into the PHANGS project.

“Laura is an expert in supernova remnants and X-ray observations, and Smita specializes in X-ray observations as well,” Thompson said. “Together, they proposed that the Chandra Space Telescope conduct a survey of all the PHANGS galaxies to analyze the hot gas within them.”

Thompson said Leroy began his journey in radio astronomy at the University of California, Berkeley, where he worked with large radio dishes and submillimeter telescopes to study molecular gases in galaxies. His career has since been marked by a commitment to integrating advanced observational data into a comprehensive picture of galactic ecosystems.

“He has consistently been a leader in incorporating data from the most advanced telescopes to get the most complete view of star formation and interstellar material,” Thompson said. 

Leroy’s ability to synthesize large amounts of complex astronomical data into a big-picture understanding of galaxy evolution has made him a leading figure in the field, Thompson said.

“He is always the person you want when discussing anything about nearby galaxies, star formation and the interstellar medium,” Thompson said. 

Leroy will be honored at an April 27 ceremony during the National Academy of Sciences’ 162nd annual meeting. Those wishing to view the ceremony remotely can register for the live stream through the National Academy of Sciences’ website.