Since their discovery by NASA's Voyager mission in the 1980s, temporary "spoke" features across Saturn's rings have fascinated scientists, yet eluded explanation. They have been observed in the years preceding and following the planet's equinox, becoming more prominent as the date approaches.

Saturn's upcoming autumnal equinox of the northern hemisphere on May 6, 2025, means that spoke season has come again. NASA's Hubble Space Telescope will be on the job studying the spokes, thanks to time dedicated to Saturn in the mission’s ongoing Outer Planet Atmospheres Legacy (OPAL) program. Are the smudgy features related to Saturn's magnetic field and its interaction with the solar wind, as prevailing theory suggests? Confirmation could come in this spoke season, as scientists combine archival data from NASA's Cassini mission with new Hubble observations.