The James Webb Space Telescope (JWST) has discovered its first exoplanet, TWA 7b, a planet that is the lightest ever directly imaged beyond our solar system. With an estimated mass of around 100 times that of Earth or 0.3 times the mass of Jupiter, TWA 7b is ten times lighter than any previously directly imaged exoplanet.
The discovery was made in the debris rings surrounding a young star called CE Antilae, located about 111 light-years from Earth. This young star is estimated to be around just a few million years old, while our sun is about 4.6 billion years old.
Astronomers were able to observe the disk of debris around CE Antilae in great detail because it was seen “pole-on” from Earth. This allowed them to see structures in the disk that appear to have been created by unseen planets and planetesimals. The JWST spotted an infrared-emitting source, which was confirmed to be a young exoplanet.
The JWST’s ability to detect infrared radiation makes it ideal for spotting young low-mass planets like TWA 7b. However, directly imaging these planets is difficult because they are drowned out by light from their parent stars. The JWST’s coronagraph technology helps block out this light, allowing the faint infrared emissions of orbiting exoplanets to be detected.
This discovery marks a significant milestone for the JWST, and it is likely that many more planets will be discovered using its capabilities. The team’s research was published in the journal Nature.
Source: https://www.space.com/astronomy/exoplanets/the-james-webb-space-telescope-has-discovered-its-1st-exoplanet-and-snapped-its-picture-image