Observations of Jupiter's moon Io by NASA's James Webb Space Telescope have provided new scientific discoveries. The observations were conducted in 2022 and 2023, and the related research results have been published in the Journal of Geophysical Research: Planets. Imke de Pater, professor of astronomy at the University of California, Berkeley and first author of the paper, said: "We detected [SI] during Io's eclipse for the first time in near-infrared JWST observations, and compared it with SO emission, evolving volcanic eruptions, and previous ultraviolet HST-STIS [SI] emissions."

Io is the most volcanically active body in the solar system, with more than 400 active volcanoes. Its surface features include giant lava lakes, among which Loki Patera has a diameter of about 200 kilometers. In 2022, a volcanic eruption in the Kanehekili region produced a lava flow covering approximately 4,300 square kilometers. Subsequent observations showed that the lava flow area had expanded fourfold.

The James Webb Space Telescope observations focused on Io's sulfur features. The study found that neutral sulfur atoms in Io's atmosphere do not come directly from volcanic activity, but originate from the interaction between electrons in Jupiter's magnetosphere and volcanic ejecta. At the same time, the telescope detected volcanic thermal radiation in the sulfur monoxide band, providing a new way to understand the temperature of the volcanic system.

These observations confirm long-held assumptions about Io's volcanic activity. Despite the ongoing volcanic activity, Io's atmosphere and surrounding plasma torus remain relatively stable. The study enhances the understanding of the interaction between Io and Jupiter's magnetosphere and provides a new perspective for the study of solar system bodies.