Northwestern scientists launch projects using the Vera C. Rubin Observatory

Northwestern researchers are teaming up across departments and disciplines to meet Rubin’s various data challenges. Tjitske Starkenburg, a research assistant professor of physics and astronomy at Weinberg, and Emma Alexander, an assistant professor of computer science at the McCormick School of Engineering, will harness AI tools to study the stars and galaxies captured by LSST. Starkenburg and Alexander will build a new AI system to uncover ultra-faint wisps on the outskirts of nearby galaxies. Miller and Han Liu, the Orrington Hunt Professor of Computer Science at McCormick and professor of statistics at Weinberg, are leading a team using AI models — that have been trained on diverse data like stock market variations and weather patterns — to better predict how stars’ brightness changes over time.

Miller also will collaborate with Aravindan Vijayaraghavan, an associate professor of computer science at McCormick, to develop new AI systems that will help schedule observations for the Rubin Observatory and other surveys.

“At any given moment, there are thousands of different locations where these telescopes could be observing,” Miller said. “Determining the optimal location — and stringing together multiple consecutive optimal observations — is a complex problem that requires information about the weather, the atmosphere and past observations. New AI models will rapidly synthesize all this information to execute the best possible strategy.”

In other work, Kalogera will collaborate with Aggelos Katsaggelos, deputy director of the SkAI Institute and the Joseph Cummings Professor of Electrical and Computer Engineering at McCormick, to develop new AI models to simulate the evolution of binary stars — condensing billions of years of evolution into mere hours. By studying these simulations, Kalogera, Katsaggelos and their team will explore how stars change over the course of their lives.

Explosive discoveries await

By consistently monitoring half the night sky, LSST will capture faint and fleeting phenomena, including supernovae, which can flare up quickly and suddenly vanish. With a constant eye toward space, astronomers expect to catch more of these transient objects.

“Right now, if you add up all the existing telescopes in the world, they catch about 40,000 new supernovae every year,” Miller said. “The Rubin Observatory will discover 2,000 new explosions every night.”

After pinpointing new supernovae, Charlie Kilpatrick, a research assistant professor at CIERA, will look at images of the sky taken before the explosions. By examining stars prior to their demise, Kilpatrick seeks to understand how stars lose mass during their death throes. For the first time, LSST will provide a detailed picture of how massive stars shed their outer layers immediately before exploding — a concept that theory has struggled to explain.

The Rubin Observatory will discover 2,000 new explosions every night.”

Wen-fai Fong, an associate professor of physics and astronomy at Weinberg, also will search for rare explosions in the distant universe. By studying these explosions, Fong and her team aim to understand where heavy elements are created and to uncover direct evidence for the origins of fast radio bursts. She also notes the possibility that the Rubin Observatory might uncover entirely new types of explosions that scientists have never seen before.

“The Rubin Observatory will instantly provide the deepest map of the southern sky in history,” Fong said. “That map will help us find distant galaxies that host cosmic explosions. In the past, I’ve had to point a telescope specifically at a location of an interesting explosion, but now the Rubin Observatory will provide that information automatically. It will be a game changer particularly in finding distant galaxies that host such explosions.”