Astronomers have captured the first-ever image of a planetary aurora on Neptune, providing insights into the interaction between this distant ice giant and the solar wind. The discovery was made possible by the James Webb Space Telescope’s powerful near-infrared spectrometer.
For years, scientists were unsure if Neptune’s unique magnetic field and hazy atmosphere would allow an aurora to form. However, recent data has revealed a sky-blue glow emanating from the planet’s equator due to particle interactions in its atmosphere. This phenomenon is similar to those observed on other planets in our Solar System.
The differences between planetary auroras are striking. Earth’s display spectacular colors when particles slam into its magnetic field, while Jupiter’s auroras shine bright ultraviolet light. The study also found that Neptune’s aurora appears at the equator due to its lopsided magnetic field, rather than at the poles as seen on other planets.
Researchers used the JWST’s temperature measurements to correct earlier predictions about Neptune’s possible auroras. Colder temperatures mean fainter auroras, and this discovery offers a new tool for understanding atmosphere-magnetosphere interactions across the Solar System.
The findings are significant, as they reveal that planetary auroras can provide valuable insights into the atmospheres and magnetic fields of distant worlds, including those orbiting other stars. This research has been published in Nature Astronomy and marks an exciting step forward in our understanding of these celestial phenomena.
Source: https://www.sciencealert.com/first-ever-images-of-neptunes-eerie-glow-finally-reveal-missing-aurora