Astronomers have captured the first known instance of an exoplanet disappearing from view as its orbit tilts out of alignment with Earth, driven by the gravitational pull of an unseen neighbor.
The distant world, designated TOI-2535 b, is a hot Jupiter located about 1,000 light-years away. It orbits its parent star once every 8.25 days, a velocity roughly ten times faster than Mercury’s journey around our Sun.
Identified in images captured by NASA’s Transiting Exoplanet Survey Satellite (TESS) between April 2019 and March 2026, the planet was routinely monitored by researchers as it crossed in front of its host star. During those seven years, astronomers noticed its transit schedule grew increasingly erratic, arriving up to six hours early or late.
The transits also grew progressively shorter and shallower until they failed to appear entirely in 2026.
According to research published in the Astrophysical Journal Letters, the planet has not actually vanished. Instead, gravitational interactions with an undiscovered neighboring planet have tilted the orbit of TOI-2535 b.
The two worlds interact so strongly that their orbits wobble like a spinning top, causing each to circle their sun obliquely. Samuel Yee, a 51 Pegasi b Postdoctoral Fellow at UCLA and a co-author on the study, described the system’s extreme nature.
We think of the universe as resembling clockwork, where everything is regular, but that’s not true. If there are multiple planets in a system, they can affect each other’s orbits. We know of a few systems that are like this, Samuel Yee, a 51 Pegasi b Postdoctoral Fellow at UCLA and a co-author on the study
Yee added that This is the most extreme example we’ve seen because the two planets are interacting so strongly. The planet’s orbit is tilting so quickly that its transit disappeared while we were watching.
Researchers note that the geometry responsible for the planet’s disappearance mirrors the mechanics governing eclipses on Earth. The tilt of the Moon’s orbit is a relic of its violent formation history, which resulted from a collision with the early Earth, and if the Moon’s orbit were perfectly aligned, there would be an eclipse each month, but its tilt makes eclipses less common.
The discovery also offers fresh clues regarding how hot Jupiters migrate close to their parent stars. Because standard formation models suggest these gas giants require ice to form, scientists believe they must originate further out before moving inward.
The presence of a close, interacting neighbor suggests that TOI-2535 b migrated by slowly spiraling inward rather than experiencing a violent near-collision that flung it toward the star. Yee noted that researchers may be seeing a formation channel that doesn’t happen very often but is very interesting.
Earlier coverage: New FLIP Technique Uses Machine Learning to Help JWST Find Exoplanets