6x bigger than Jupiter: NASA's Webb telescope discovers giant exoplanet
The James Webb Space Telescope (JWST) has photographed an exoplanet that is estimated to be nearly six times bigger than Jupiter. The exoplanet, named Epsilon Indi Ab, orbits a star called Epsilon Indi A, which is similar in size and age to our Sun. This system is located less than 12 light-years away from us. Jupiter is the largest planet in our solar system, boasting a radius of approximately 69,900 kilometers, which makes it about 11 times wider than Earth.
Webb's unique technique for imaging
To directly image an exoplanet, the JWST employs a piece of hardware known as a coronagraph. This device blocks the light from the star that the planet orbits, preventing it from overpowering other sources in the exosolar system. For successful imaging, planets must orbit at a significant distance from their star to be cleanly separated from the signal being blocked by the coronagraph.
Epsilon Indi Ab: One of the coolest exoplanets ever imaged
With a temperature of around 1.85-degree celsius, Epsilon Indi Ab is one of the coolest exoplanets ever directly imaged by JWST. Interestingly, it could not be detected in one area of the spectrum (3.5 to 5 micrometers), suggesting that it has high levels of elements heavier than helium and a high ratio of carbon to oxygen. Further observations are likely to be conducted to clarify why there are no emissions at these wavelengths.
Discovery aids in understanding planetary evolution
The discovery of Epsilon Indi Ab could help astronomers better understand the evolution of gas giant planets and their systems. "We were excited when we realized we had imaged this new planet," said Elisabeth Matthews, a researcher at the Max Planck Institute for Astronomy in Heidelberg, Germany. The team was able to correct previous underestimations of this super-Jupiter gas giant's mass and orbital separation with the help of JWST.
