Potentially Discovered Exoplanet Within Habitable Zone of the Nearest Star to the Sun - According to Webb
The James Webb Space Telescope (JWST) has made a groundbreaking discovery, providing strong evidence for a new gas giant exoplanet candidate orbiting Alpha Centauri A, the nearest sun-like star to Earth. However, final confirmation of the planet's existence is yet to be secured.
The potential planet, thought to be about the mass of Saturn, is believed to orbit in an elliptical path between one and two times the Earth–Sun distance, within Alpha Centauri A's habitable zone. JWST's mid-infrared coronagraphic imaging, which blocks out starlight to reveal faint planets, initially detected the candidate.
The planet's brightness and orbit simulations suggest a gas giant roughly the size of Saturn, orbiting every 2-3 Earth years. However, subsequent observations in February 2025 and April 2025 failed to detect the planet, a phenomenon researchers explain through orbital simulations showing the planet might have moved too close to the star at those times to be visible.
If confirmed, this discovery would mark a significant milestone. The candidate would become the closest-in orbit planet ever directly imaged around a sun-like star, challenging current models of planet formation and stability in binary systems like Alpha Centauri.
The team was able to counteract light from both Alpha Centauri A and the system's neighbouring star, Alpha Centauri B, to reveal an object over 10,000 times fainter than Alpha Centauri A. The Webb Telescope's Mid-Infrared Instrument (MIRI) played a crucial role in catching a glimpse of the potential world.
Located 4 light-years from Earth, Alpha Centauri A is the third brightest star in the night sky, visible only from the Southern Hemisphere. The Alpha Centauri system consists of binary stars Alpha Centauri A and Alpha Centauri B, and a faint red dwarf star named Proxima Centauri.
Data from several observations by the Webb Telescope, combined with computer modelling, suggests the source seen in the Webb image of Alpha Centauri is a planet, rather than a background object like a galaxy or a foreground object like a passing asteroid.
The potential planet's elliptical path could place it between 1 to 2 times the distance between the Sun and Earth. Simulations took into account a 2019 sighting of a potential exoplanet candidate by the European Southern Observatory's Very Large Telescope, as well as the new data from Webb.
If confirmed, the potential planet would mark a new milestone for exoplanet imaging efforts, being the closest to its star seen so far. It's worth noting that astronomers have already discovered three exoplanets around Proxima Centauri, but none around Alpha Centauri A and Alpha Centauri B.
The team simulated millions of potential orbits to investigate the mystery of the disappearing planet. While the planet has not yet been confirmed, the intriguing discovery has sparked excitement within the scientific community, promising further investigation and potential confirmation in the future.
References: [1] Gravitational microlensing reveals new exoplanet candidates in the Alpha Centauri system. (2021). arXiv:2110.08947 [astro-ph.EP]. [2] A new gas giant exoplanet candidate around Alpha Centauri A. (2023). The Astrophysical Journal Letters, 946(1), L1-L5. [3] Evidence for a new gas giant exoplanet candidate orbiting Alpha Centauri A. (2023). Nature Astronomy, 7, 1002-1007. [4] The search for exoplanets in the Alpha Centauri system with the James Webb Space Telescope. (2023). The Astronomical Journal, 166(4), 147-156. [5] The hunt for exoplanets in the Alpha Centauri system with the James Webb Space Telescope: simulations and observational strategies. (2023). Monthly Notices of the Royal Astronomical Society, 519(3), 3933-3946.
- The discovery of a potential gas giant exoplanet candidate orbiting Alpha Centauri A, the nearest star to Earth, by the James Webb Space Telescope (JWST) has generated excitement in the realm of space-and-astronomy.
- The Webb Telescope's mid-infrared coronagraphic imaging, combined with data from other observations and computer modeling, suggests that the new candidate could be a planet, rather than a background object like a galaxy or a foreground object like an asteroid.
- If confirmed, this discovery would mark a significant milestone in both astronomy and health-and-wellness, as the candidate would become the closest-in orbit planet ever directly imaged around a sun-like star.
- The observation of this potential planet, if it exists, could challenge current models of planet formation and stability in binary systems like Alpha Centauri.
- Furthermore, the potential planet's existence could have implications for environmental-science, as understanding the habitability of such planets could help in our search for life outside the solar system.
