Astronomers have discovered a new planet, Kepler-51e, in the “super-puff” system of Kepler-51. The discovery was made using NASA’s James Webb Space Telescope (JWST) and confirms that the system has at least four planets.
The three previously known planets in the system are ultra-low density “super-puffs,” meaning they have very low mass and density, similar to cotton candy. Researchers used JWST to study one of these planets but almost missed the chance when a fourth planet unexpectedly passed in front of its star two hours earlier than models predicted.
By adding a new planet, Kepler-51e, to their model, researchers explained the discrepancy. The planet has an orbit similar to that of Venus and is just inside the star’s habitable zone. Further study is needed to understand the impacts of its gravity on the other planets in the system.
The discovery was made by a team of international researchers led by Kento Masuda and John Livingston, who coordinated most of the ground-based follow-ups. The team used archival data from NASA’s Kepler space telescope, TESS, Hubble Space Telescope, Palomar Observatory telescope, and several ground-based telescopes to support their new models.
The research reveals that accounting for a fourth planet changes the expected masses of the other planets in the system, impacting inferred properties about these planets and informing how they might have formed. However, it is unclear if Kepler-51e is also a super-puff planet due to the lack of observations.
With the rest of the JWST data still being analyzed, researchers hope that further study will provide information about the atmosphere of Kepler-51d and improve understanding of the formation of these unusual ultra-low-density planets.
Source: https://phys.org/news/2024-12-webb-planet-kepler-super-puff.html