James Webb Telescope Finds — Then Loses — Giant Exoplanet Near Alpha Centauri That May Have Water
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| Illustration of a giant exoplanet near the star Alpha Centauri A observed by the James Webb Space Telescope. |
An international team of astronomers has made a surprising discovery. In 2024, the James Webb Space Telescope detected a giant exoplanet about the size of Saturn near Alpha Centauri A, one of the closest stars to Earth.
But in 2025, efforts to locate the planet again completely failed. Scientists suspect the planet temporarily “vanished” by being hidden in the glare of its star, making it invisible to Webb’s instruments.
Based on researchers’ calculations, the object could reappear in 2026 or 2027. If confirmed, it would become the closest known world located in the habitable zone—the region around a star where liquid water could exist. However, its massive size makes the likelihood of Earth-like life very low.
“The signal was extremely faint, right at the edge of the telescope’s capabilities. Any conclusions will require independent verification,” said one of the scientists involved in the study.
Alpha Centauri is a triple-star system made up of Alpha Centauri A, Alpha Centauri B, and the red dwarf Proxima Centauri.
Located just four light-years away, it’s considered a prime target for searching for planets beyond our solar system.
To observe the mysterious object, the team used Webb’s infrared instrument equipped with a coronagraph—a device that blocks starlight to reveal fainter objects nearby.
In 2027, the search will be joined by the upcoming Nancy Grace Roman Space Telescope. It’s expected to scan an area of the sky 100 times larger than Hubble with comparable resolution and will feature an experimental coronagraph for directly imaging exoplanets.
With both telescopes working together, the chances of confirming this giant planet’s existence could greatly improve, potentially opening a new chapter in the search for alien worlds.
