Credit: NASA, ESA, A.Simon (GSFC), A. Pagan (STScI)

NASA’s Hubble Space Telescope has observation time devoted to Saturn each year, thanks to the Outer Planet Atmospheres Legacy (OPAL) program, and the dynamic gas giant planet always shows us something new. This latest image heralds the start of Saturn’s “spoke season” with the appearance of two smudgy spokes in the B ring, on the left in the image.

The shape and shading of spokes varies—they can appear light or dark, depending on the viewing angle, and sometimes appear more like blobs than classic radial spoke shapes, as seen here. The ephemeral features don’t last long, but as the planet’s autumnal equinox approaches on May 6, 2025, more will appear. Scientists will be looking for clues to explain the cause and nature of the spokes. It’s suspected they are ring material that is temporarily charged and levitated by interaction between Saturn’s magnetic field and the solar wind, but this hypothesis has not been confirmed.

Provider: Space Telescope Science Institute

Image Source: https://hubblesite.org/contents/news-releases/2023/news-2023-005

Curator: STScI, Baltimore, MD, USA

Image Use Policy: https://www.stsci.edu/copyright