Astronomers Observe Rare Planetary Collision 11,000 Light-Years Away
Researchers have detected a rare collision between two planets around the star Gaia20ehk, providing insights into planetary formation processes.
Astronomers have observed a rare cosmic event: a collision between two planets approximately 11,000 light-years from Earth, near the constellation Puppis. The discovery was made by Anastasios Tzanidakis, a doctoral candidate at the University of Washington, who noticed unusual fluctuations in the brightness of the star Gaia20ehk while reviewing archived telescope data from 2020. The star, similar to our sun, began exhibiting unexpected dips in brightness starting in 2016, followed by significant variability around 2021. Further analysis revealed that these fluctuations were caused by massive clouds of hot dust and debris passing in front of the star, likely resulting from a violent collision between two planets in the system. This event offers valuable insights into planetary formation processes and may resemble the collision that led to the formation of Earth's moon. The findings were published on March 11, 2026, in the Astrophysical Journal Letters.