A Giant Planet Vanished From NASA's View, and a Hidden Neighbor Is Why

A giant planet about 1,000 light years away has dropped out of sight in data from NASA's TESS space telescope, and astronomers now think a hidden neighbor is the reason, according to Universe Today. The planet, a hot Jupiter named TOI-2535b, did not actually vanish. Its orbit is tilting so quickly that it no longer passes in front of its star as seen from Earth.

The finding, published in The Astrophysical Journal Letters, is the first confirmed case of a planet around a single star whose transits were watched disappearing, the study's authors say.

How a planet can leave the frame

TESS finds planets by the transit method: it watches for the small dip in a star's light when a planet crosses in front of it. That only works when the orbit lines up almost edge-on with our view. The authors write that a planet is seen to transit only when its orbit is within a few degrees of that alignment, so even small changes in tilt can alter the shape of a transit.

TESS observed multiple transits of TOI-2535b over seven years. Then the signal faded. By following the planet over several years, astronomers saw that the change was gradual: both the timing and the shape of the transit shifted slowly rather than the planet disappearing at once.

The neighbor pulling on the orbit

The researchers conclude that another planet, with a mass of at least that of Saturn, is tugging on TOI-2535b and tilting its orbit. The study's corresponding author, Samuel Yee of UCLA, said the two planets are interacting so strongly that the orbit tilts fast enough for the transit to disappear while astronomers were watching.

Yee said people tend to picture the universe as regular clockwork, but planets in a system with several worlds can affect each other's orbits. He called this the most extreme example he and his colleagues have seen.

The study points to several records for this system. According to the authors, it has the largest changes in transit duration and the largest orbital tilt change ever observed for a planet orbiting a single star, with a precession period of decades, shorter than in other known systems. It also shows some of the largest variations in transit timing ever detected, and the largest ever for a hot Jupiter.

Why this system is surprising

Hot Jupiters are not expected to have close neighbors, and when they do, the neighbors are usually much less massive. Universe Today reported that TOI-2535b is one of only a handful of hot Jupiters known to have a nearby planetary companion. The likely companion here is a second short-period giant planet. In all but one of the other known cases, the companions are sub-Neptunes or super-Earths.

A pair of massive gas giants circling one star in resonance is also not something current planet-formation models predict.

Why it matters for planet hunting

The result is a reminder that a planet missing from the data is not necessarily missing from the sky. Transit surveys depend on a lucky alignment, and the study shows that alignment can be temporary. Some worlds that once showed up in survey data may later slip out of view, and others that were never seen could drift into it.

The result also arrives as TESS continues its work. Universe Today reported that, as of mid-October 2026, the mission has identified more than 8,100 candidate exoplanets, with just over 1,000 confirmed. Astronomers are also finding more planets in its archive using new machine learning techniques.

Around Prague, based on reporting by Universe Today

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