Saturn’s “spoke season” is a fascinating phenomenon that happens on its rings. These spokes are mysterious, dark, radial features that appear on Saturn’s rings, resembling the spokes of a wheel. They show up when Saturn’s equinox is approaching, which is about every 15 Earth years.

Scientists think they might be caused by Saturn’s magnetic field interacting with ring particles, but they’re still not entirely sure.

It’s one of those cool space mysteries that keeps astronomers scratching their heads and looking up in awe.