A giant planet roughly 1,000 light-years from Earth has gradually disappeared from view, and astronomers believe an unseen companion is responsible. Researchers at UCLA have described the case of Toi-2535 b, a hot Jupiter that circles its star every 8.25 days, a pace far faster than Mercury's roughly 88-day orbit around the Sun.
The planet had long been tracked by NASA's TESS satellite, which watches for the slight dimming that occurs when a world passes in front of its star. Between 2019 and 2026, those transits changed in ways that puzzled the team. They began arriving early or late by as much as six hours, grew shorter, and moved closer to the edge of the stellar disk. Eventually they stopped altogether.
The explanation the researchers favor is gravitational. A second planet, likely a gas giant with at least the mass of Saturn and on a tight orbit of its own, may be pulling on the inner world and tilting its path so that it no longer crosses in front of its star from our vantage point. If that is correct, the transit could return in several decades, when the orbit has shifted back into line.
The configuration also raises questions about how such a system forms. Two giant planets packed so closely together are unusual, and the tilt of the inner orbit does not fit simple models of planets forming from a flat disk of gas and dust. The team suggests the inner planet may have migrated inward through a spiraling process, rather than being violently flung into its current position.
The findings, led by Samuel Yee, have been published in The Astrophysical Journal Letters.
Credit. Based on reporting by Gaia Mantovani for Media INAF. Is this your work? Write to us.
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