New Evidence for Massive Planetary Collision: Discovery of TOI-1853b

Astronomers have identified the Neptune-sized exoplanet TOI-1853b with unusually high density and mass, making a breakthrough discovery that suggests a major planetary collision occurred during its formation. A study by Luca Naponiero of Rome’s Tor Vergata University, published in the journal Nature, shows that these large-scale collisions removed light air and water, resulting in a mass of mostly rock. suggesting that a new planet was formed. The international research team also includes a Ph.D. Phil Carter of the University of Bristol’s Department of Physics believes the discovery provides evidence for the prevalence of giant impacts during planet formation. These collisions shed light on the diversity of planets in exoplanetary systems and advance our understanding of how planets form inside and outside our solar system. His co-author and PhD student, Jingyao Dou, explains that despite the size of Neptune, TOI-1853b is denser than steel. This anomaly can be explained by very high-energy interplanetary collisions that occur during planet formation, resulting in the removal of light elements, leaving behind dense, rock-rich planets. The research team plans to conduct further observations of TOI-1853b to detect residual atmosphere and study its composition. This discovery represents an important step in improving material models and broadening the spectrum.


– University of Bristol

– Nature (DOI: 10.1038/s41586-023-06499-2)