'Super Jupiter': James Webb Telescope discovers the coldest known exoplanet, which completes one orbit of its star in 250 years
Produced by: Tarun Mishra
Discovery by James Webb Telescope
The James Webb Space Telescope, the largest and most powerful telescope launched into space, has discovered a "super Jupiter" around a neighbouring star, making it the 12th closest exoplanet to Earth.
Exoplanet Epsilon Indi Ab
The newly discovered exoplanet, named Epsilon Indi Ab, is the closest planet larger than Jupiter. It is notable for being one of the coldest exoplanets observed to date.
Planet Characteristics
Epsilon Indi Ab has a diameter similar to Jupiter but possesses six times the mass. Despite its size, it has a remarkably long orbital period, taking over a century, possibly up to 250 years, to orbit its star.
Hydrogen-Rich Atmosphere
The planet's atmosphere is rich in hydrogen, akin to that of Jupiter, which contributes to its classification as a "super Jupiter."
Observation with MIRI
An international team of astronomers used the coronagraph on Webb's Mid-Infrared Instrument (MIRI) to observe Epsilon Indi Ab. This direct imaging feat is significant, as only a few exoplanets have been directly imaged by space and ground-based observatories.
Imaging Challenges
Most previously photographed exoplanets are young and hot, emitting significant energy. Epsilon Indi Ab, being a colder and older planet, posed a greater challenge for direct imaging due to its faint emission as it cools and contracts over time.
Research Publication
The findings were detailed in a research article titled "A temperate super-Jupiter imaged with JWST in the mid-infrared," published in the journal Nature on July 24.
Expert Insights
Elisabeth Matthews from the Max Planck Institute for Astronomy highlighted the excitement of discovering a planet similar to Jupiter but slightly warmer and more massive. She emphasized the importance of Webb's mid-infrared imaging capabilities for this discovery.
Future Observations
Caroline Morley of the University of Texas at Austin noted that prior indirect measurements suggested the presence of a giant planet in the system. The team's observations with Webb aim to further investigate this intriguing exoplanet and its star.