Astronomers collaborating with citizen scientists have discovered a Neptune-sized planet in a binary star system. TOI 4633 c, also known as Percival, orbits around a pair of stars located approximately 309 light-years away from Earth. This planet was initially detected using the transit method, which identifies planets with orbits close to their host star. However, TOI 4633 orbits unusually far from its star, taking 272 days to complete one orbit.
This discovery sets a record for the brightest known host of a transiting planet in the “habitable zone,” where conditions for liquid water to exist on the planet’s surface are optimal. Researchers also speculate the presence of a second planet in the system that completes an orbit around the star every 34 days. These findings are detailed in a paper published in the Astrophysical Journal.
Lead author Nora Eisner, a research fellow at the Flatiron Institute’s Center for Computational Astrophysics in New York City, emphasizes the significance of discovering planets in multi-star systems for a deeper understanding of planet formation. Citizen scientist Simon Bentzen, who has been involved with Planet Hunters TESS since 2018, shares his excitement about contributing to the discovery of this new system and the potential insights it could offer into planetary science.
The Planet Hunters project has engaged over 43,000 volunteers from 90 countries to assist in cataloging about 25 million objects. Upon receiving reports from 15 citizen scientists flagging a possible new planet, Eisner’s team conducted follow-up studies that confirmed TOI 4633’s existence. This discovery opens up possibilities for further exploration, such as the potential presence of a moon with a solid surface that could be conducive to finding water.
