NASA’s James Webb Space Telescope has discovered strong evidence of a gas giant planet orbiting the star Alpha Centauri A, located just 4 light-years away from Earth. This detection is significant as it would be the closest to our home star that orbits in the habitable zone of a Sun-like star.
Alpha Centauri, comprising two Sun-like stars and a faint red dwarf star, has long been a promising target in the search for worlds beyond our solar system. The system’s proximity to Earth makes it an ideal location for scientists to study planetary systems other than our own.
The gas giant planet is believed to be approximately the mass of Saturn and orbits Alpha Centauri A at a distance between 1 to 2 times that of the Sun-Earth distance. While this discovery would mark a milestone in exoplanet imaging efforts, it’s essential to note that the presence of life on such a planet remains uncertain due to its gas giant nature.
The James Webb Space Telescope’s observations were made using its Mid-Infrared Instrument (MIRI) and involved meticulous planning, careful analysis, and extensive computer modeling. The team successfully detected an object over 10,000 times fainter than Alpha Centauri A in the star’s vicinity.
However, subsequent observations did not reveal any additional objects like the one identified in August 2024, leading researchers to conclude that their initial detection was genuine. Further studies using computer simulations and the upcoming launch of NASA’s Nancy Grace Roman Space Telescope may help confirm or refute this finding.
This breakthrough discovery highlights the potential of the James Webb Space Telescope as a tool for advancing exoplanet science and our understanding of planetary formation in chaotic environments.
Source: https://webbtelescope.org/contents/news-releases/2025/news-2025-135