NASA’s James Webb Space Telescope has provided a groundbreaking discovery about the mysterious event of a star swallowing its own planet. Contrary to previous theories, new findings suggest that the planet’s orbit shrunk over time, bringing it closer to its demise until it was engulfed in full.
A team of astronomers led by Ryan Lau used Webb’s powerful instruments to study this rare phenomenon, known as a Target of Opportunity (ToO) observation. They targeted the star ZTF SLRN-2020, located 12,000 light-years away from Earth, which initially appeared as an optical flash and later brightened in infrared.
Webb’s Mid-Infrared Instrument (MIRI) revealed that the star was not swelling to engulf the planet as once thought, contradicting previous theories. Instead, researchers found evidence of a shrinking orbit, indicating the planet had fallen into a catastrophic process.
“We were surprised by what we saw,” said Morgan MacLeod, team member from Harvard-Smithsonian Center for Astrophysics. “The planet was slowly falling in and eventually grazing the star’s atmosphere, triggering a runaway process that led to its engulfment.”
Further analysis revealed a hot circumstellar disk of molecular gas closer to the star, with detectable molecules such as carbon monoxide. These findings provide new insights into the final fates of planetary systems, possibly including our own.
“This is a transformative discovery,” said Colette Salyk, an exoplanet researcher and co-author on the paper. “We’re only just starting to understand what happened after the planet was fully swallowed by the star.”
The James Webb Space Telescope’s Target of Opportunity programs are designed to investigate rare events like supernova explosions. With the upcoming Vera C. Rubin Observatory and NASA’s Nancy Grace Roman Space Telescope, researchers expect to add to their sample and identify future events.
This groundbreaking study provides a new understanding of celestial events and further solidifies Webb’s role as a premier space science observatory.
Source: https://webbtelescope.org/contents/news-releases/2025/news-2025-117.html