A new planet in a binary star system has been discovered by a group of astronomers and citizen scientists. Located around 309 light-years away from Earth, the Neptune-sized planet, known as TOI 4633 c or Percival, orbits around a pair of stars. Initially detected by citizen scientists reviewing data collected by NASA’s Transiting Exoplanet Survey Satellite (TESS), the planet was observed passing in front of one of its host stars, causing a temporary dimming of the star’s light.
This discovery is unique because TOI 4633 orbits unusually far from its star, taking 272 days to complete one orbit. In addition, it is a record-breaking find as its star is the brightest known host of a transiting planet in a “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.
The lead author of the paper published in the Astrophysical Journal is Nora Eisner, a research fellow at the Flatiron Institute’s Center for Computational Astrophysics in New York City. Eisner highlights 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, expresses his excitement in contributing to the discovery of this new system and potential insights into planetary science.
Through the Planet Hunters project, TESS 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.
