@space_telescopes

class="content__text" This new image of Saturn from the Hubble Space Telescope holds a subtle detail of great interest to ring-watchers: On the left, two dark smudges indicate the start of a new “spoke season.” In the years surrounding Saturn’s equinox—which occurs every 16 Earth-years, with the next on May 6, 2025—mysterious, temporary spoke features have been spotted in the rings. They can appear light or dark against the rings, depending on the illumination and viewing angle. Closer to the equinox, their appearance is expected to become more frequent and distinct. So far scientists have been unable to explain the spokes, which have a slightly different rotation rate than the rings themselves. In the next several years, Hubble’s Outer Planet Atmospheres Legacy (OPAL) program will be used to confirm or refute theories about the spokes, the most popular being that they result from interaction between the planet’s magnetic field and the solar wind, levitating ring particles to create the spoke features. #Hubble #Saturn #SaturnRings #SolarSystem #spokes Credit: NASA, ESA, STScI, Hubble OPAL program; image processing: Alyssa Pagan (STScI). ALT TEXT: Planet Saturn with bright white rings and multi-colored main sphere. Spoke features on the left side of the rings appear like faint gray smudges against the rings’ bright backdrop, about midway from the planet to the rings' outer edge. Above the rings plane, the planet's bands are shades of red and orange, with brighter yellow nearer the equator.

February 12, 2023