UCLA-led astronomers reported on November 9 that a giant planet about 1,000 light-years from Earth has stopped passing in front of its star from our point of view. Their study in The Astrophysical Journal Letters attributes the vanishing transits of TOI-2535 b to an orbital tilt driven by the gravity of a second, still unseen planet. The first planet itself has not disappeared.
TOI-2535 b is a hot Jupiter, a gas giant close to its host star that completes an orbit in roughly 8.25 days. Researchers followed its transits, the brief dips in starlight produced when a planet crosses its star, in observations from NASA’s TESS telescope spanning April 2019 to March 2026. A transit is visible only when the orbit lines up closely with Earth.
According to the UCLA team, those crossings arrived as much as six hours earlier or later than a regular orbital timetable predicted. They also grew shorter and shallower across the seven-year record before no transit appeared in 2026. The changing timing and shape gave the researchers evidence that the planet’s orbital plane was shifting.
The team’s calculations indicate that an unseen neighboring planet, on an orbit tilted relative to TOI-2535 b, exerts enough gravitational force to make the two orbits precess. The shift moves the hot Jupiter out of the narrow alignment needed for a transit. UCLA said precise observations with the WIYN 3.5-meter telescope in Arizona also helped establish that the known planet is Jupiter-sized and extremely hot.
The result offers a rare way to study how planets affect each other without directly seeing both worlds. UCLA researchers say the unusually strong interaction could also inform competing explanations for how hot Jupiters move inward toward their stars. They suggest that the nearby companion may favor a gradual inward migration, although the system’s formation history remains an interpretation of the data.
The researchers forecast that TOI-2535 b may cross its star again in 30 to 50 years as its orbit changes orientation; the hidden neighbor could become visible in transit sooner. Further observations could test the orbital model and reveal more about the second planet. The current finding concerns a changing viewing angle, rather than the loss of a planet.
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