A Giant Exoplanet is Spiraling Toward Its Star

By Space.Fan Editorial DeskSeptember 24, 2026 at 4:00 AM UTC

Astronomers found that a massive, hot planet is slowly being pulled into its host star and likely has a hidden neighbor.

Image · Space.Fan

The Drop

Scientists have been watching an extreme named TOI-2109 b. It is a giant world, much bigger and heavier than Jupiter, that orbits its faster than any other known giant . It completes a full lap around its sun in less than one Earth day. Because it is so close to its , the ’s gravity is causing the ’s orbit to slowly shrink. This process is known as orbital decay, where the inches closer to the over time. To track this, researchers used powerful space telescopes, including the James Webb Space Telescope and the Hubble Space Telescope. They measured the tiny dips in light that occur when the passes in front of its , known as transits. By comparing these observations with older data from other telescopes, they noticed the is arriving at these checkpoints a little bit early, signaling that its path is tightening. Additionally, the team discovered a repeating pattern in the timing of these transits. This rhythm suggests that the big might have a smaller, hidden neighbor nearby whose gravity is tugging on it.

Why It Matters

This discovery helps astronomers understand how giant s move and change over their lifetimes. Finding a in the act of falling toward its is very rare. By studying this, scientists can learn more about the internal secrets of s and how they interact with the massive worlds that orbit them closely.

The Catch

While the evidence for the 's movement is strong, the researchers note that they cannot be 100 percent sure it is falling into the . It is possible that some other effect, like the way our telescopes look at the system from Earth, might be causing the measurements to look like an orbital decay. Future observations will be needed to confirm exactly what is happening to this world.

Put That in Perspective

Only one other exoplanet, known as WASP-12 b, has been observed in a similar state of orbital decay. TOI-2109 b now stands as the most extreme example of this rare class of planets, providing a unique chance for researchers to test their theories about planetary migration.

Source September 24, 2026

Michael Greklek-McKeon, Julie Inglis, Nicole L. Wallack, Shreyas Vissapragada, Ian Wong, John R. T. Allen, Yayaati Chachan, Fei Dai, Guangwei Fu, Tiffany Kataria, Thaddeus D. Komacek, Johanna K. Teske

AAS Journals·10.48550/arXiv.2609.26894