We finally know why a distant exoplanet mysteriously vanished
What's the story
The mystery of the missing exoplanet TOI-2535 b has been solved by astronomers. The planet, which is located about 1,000 light-years away from Earth, was thought to have vanished after seven years of observations with NASA's Transiting Exoplanet Survey Satellite (TESS). However, new research suggests that it hasn't disappeared at all but has instead been dragged off its orbit by an unseen neighbor.
Orbital anomalies
TOI-2535 b was thought to have vanished
TOI-2535 b, a "hot Jupiter" with 8.25-Earth day orbit, was observed by TESS from April 2019 to March 2026.
However, during these observations, astronomers noticed something strange about the planet's orbit.
Unlike other planets whose orbits are regular, TOI-2535 b often arrived six hours early or late than expected.
Then in March this year, TESS stopped detecting the dips in starlight caused by TOI-2535 b transiting across its parent star's face, making it appear as if the exoplanet had vanished.
Orbital wobble
Unseen neighbor is pulling TOI-2535 b off its orbit
The research team used TESS data to conclude that an unseen planet is pulling TOI-2535 b off its orbit.
This interaction is causing both planets in the TOI-2535 system to "wobble."
The wobble tilted TOI-2535 b out of alignment with its star, which explains why it disappeared from observations.
Samuel Yee, a team member from UCLA, explained this phenomenon by saying that "multiple planets in a system can affect each other's orbits."
Planetary formation
What does this mean for the future of TOI-2535 b?
TOI-2535 b won't be transiting its parent star for at least another 30 years. However, the hidden neighbor that is pulling on it may cross the face of the star sooner than that.
Meanwhile, scientists are trying to decode what this extreme wobbling exoplanet system says about its formation.
Hot Jupiters like TOI-2535 b are thought to form far from their stars and then migrate inward due to various processes like violent near-collisions/interactions with a protoplanetary disk around infant star.