About 1,200 light-years from Earth, in the constellation Auriga, a giant planet is circling its star so closely that it is being pulled apart. The world, called WASP-12b, whips around its sun once every day or so, and the star’s gravity is stretching it out of shape and stripping gas from its atmosphere. Astronomers describe it as one of the clearest known examples of a planet being consumed by the star it orbits.
A hot Jupiter on a one-day orbit
WASP-12b belongs to a category of planets known as hot Jupiters, gas giants comparable in bulk to Jupiter but orbiting extraordinarily close to their host stars. It is roughly 1.8 times the radius of Jupiter and around 1.4 times its mass, and it completes a full orbit in only about 1.1 days. That proximity bakes the planet to a temperature of roughly 4,000 degrees Fahrenheit, hot enough to glow.
The planet was identified in 2009 using the transit method, in which astronomers watch for the small, regular dip in a star’s brightness caused by a planet passing in front of it. NASA’s catalog entry for WASP-12b records these basic parameters and situates the world among the extreme close-in giants that have become laboratories for studying how planets behave under punishing stellar heat and gravity.
Stretched into the shape of an egg
Because WASP-12b sits so near its star, the gravitational pull on its near side is dramatically stronger than the pull on its far side. That difference produces enormous tidal forces, the same kind of effect that raises ocean tides on Earth but vastly amplified. Instead of remaining spherical, the planet is deformed into an elongated, egg-like shape, with its long axis pointing toward the star.
This distortion is not a cosmetic detail. Stretching the planet loosens its grip on its own outer layers, making it easier for the star to peel material away. NASA’s description of the world as an egg-shaped exoplanet ties the strange geometry directly to the ongoing loss of mass, framing the shape as a visible sign of a planet under siege.
How the star pulls the planet apart
The destruction works on two fronts. The intense heat inflates and energizes the planet’s atmosphere, causing gas to expand outward, while the star’s gravity draws that escaping material away from the planet. Rather than falling straight in, much of the lost gas forms a disk of material swirling around the star, fed continuously by the planet’s bleeding atmosphere.
Observations with the Hubble Space Telescope detected signatures of this process, including evidence that the planet’s atmosphere is being stripped and that heavy elements are present in the surrounding gas. The findings, summarized in NASA’s report on a star eating a planet, provided some of the first direct evidence that a star was actively feeding on one of its own planets rather than simply hosting it.
A countdown measured in millions of years
The rate of loss means WASP-12b has a limited future. NASA has estimated that the planet could be completely consumed within roughly 10 million years, an eyeblink by astronomical standards, where stars and planets are typically billions of years old. Some later research has argued the timeline may be even shorter, on the order of a few million years, as the planet spirals gradually inward toward its star.
Whatever the precise figure, the outcome is the same. The planet is both losing mass to the star and slowly drawing closer to it, a combination that ends with the remaining material being absorbed. WASP-12b offers a rare chance to watch that endgame in progress rather than to infer it after the fact.
Why a doomed planet is scientifically valuable
Extreme worlds like WASP-12b are useful precisely because they push physics to its limits. Studying how the planet’s atmosphere responds to relentless heat helps researchers model the behavior of gases under conditions that cannot be reproduced on Earth. The material streaming off the planet also lets astronomers analyze what a giant planet is made of, since escaping gas carries chemical fingerprints that can be measured as it crosses in front of the star.
The system additionally serves as a case study in how planetary orbits decay. Understanding the forces that drag WASP-12b toward its star informs broader questions about how common such close-in giants are, how long they survive, and what happens to the planets that migrate too near their suns. Each of these lines of inquiry benefits from having a clear, actively disintegrating example to observe.
A preview of a violent fate
WASP-12b will not survive as a planet, and its slow dismantling illustrates that planetary systems are not fixed arrangements. Worlds can migrate, collide, and, in cases like this one, be destroyed by the very star that gave them warmth and light. The process is silent and invisible to the naked eye across such distances, but the instruments trained on the system have captured a world in the act of vanishing.
For now the planet remains, distorted and shedding gas, tracing its rapid orbit around a star that is steadily reclaiming it. In the long arc of cosmic time it is already fading, a giant planet caught in a fatal embrace and being unmade piece by piece.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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