James Webb reveals a strange bulge in an alien planet's atmosphere

Astronomers have long depicted distant exoplanets with smooth, circular outlines. But new observations reveal that the atmospheres surrounding some of these scorching alien worlds can have surprisingly uneven shapes.

Using NASA's James Webb Space Telescope (JWST), researchers have discovered that the atmosphere of WASP-17b, a giant planet roughly 1,300 light-years from Earth, extends farther outward on one side than the other. Although its overall outline remains approximately circular, its atmosphere is noticeably asymmetrical. The distortion provides new evidence of how extreme temperatures and powerful winds reshape the atmospheres of distant planets.

The discovery, published in Nature Astronomy , comes from a study jointly led by Cornell University in the United States and the University of Bristol in the United Kingdom. Researchers used an innovative technique called 'transmission strings', developed by Bristol astrophysicists Dr. David Grant and Dr. Hannah Wakeford, to investigate the planet's atmospheric structure in unprecedented detail.