Produced by: Tarun Mishra Designed by: Manoj Kumar
A fourth planet, Kepler-51e, has been identified in the Kepler-51 planetary system, famous for its "super-puff" planets with ultra-low densities. The discovery, led by Dr. Jessica Libby-Roberts of Penn State and Dr. Kento Masuda of Osaka University, sheds light on variations in the transit timings of the system’s previously known planets.
Located 2,615 light-years away, the Kepler-51 system is unique due to its planets’ exceptionally low densities, often compared to cotton candy. The addition of Kepler-51e further highlights the complexity and intrigue of this system.
The discovery stemmed from an anomaly observed during a planned study of Kepler-51d with NASA's James Webb Space Telescope (JWST). Researchers noted that the planet’s transit occurred two hours earlier than expected, prompting further investigation.
The team reanalysed data from NASA’s Kepler and TESS telescopes, the Hubble Space Telescope, and ground-based observatories, including the Apache Point Observatory and Palomar Observatory. This analysis confirmed that a four-planet gravitational model best explained the transit variations.
Kepler-51e is thought to have a mass similar to the system's other planets and orbits its star in approximately 264 days. However, its radius and density remain undetermined, leaving open the question of whether it shares the "super-puff" classification.
The discovery led to slight revisions in the estimated masses of the other planets—Kepler-51b, Kepler-51c, and Kepler-51d—while maintaining their ultra-low-density status.
Kepler-51e’s orbit lies just inside the system’s habitable zone, raising possibilities of additional planets farther out. This positioning provides valuable information on gravitational interactions and the system’s overall dynamics.
The JWST continues to analyse the atmospheric composition of Kepler-51d, which may reveal more about the formation of super-puff planets. The study of Kepler-51e and its neighbouring planets is expected to deepen understanding of planetary formation and dynamics, contributing to broader explorations of habitability in distant systems.