Illustration of the Kepler-51 system and its three inner planets, characterized by extremely low density. New observations from NASA's James Webb Space Telescope indicate that at least one more planet exists in the system. Credit: NASA, ESA L. Hustak, J. Olmsted, D. Player F. Summers (STScI).

Illustration of the Kepler-51 system and its three inner planets, characterized by extremely low density. New observations from NASA's James Webb Space Telescope indicate that at least one more planet exists in the system. Credit: NASA, ESA L. Hustak, J. Olmsted, D. Player F. Summers (STScI).