About once a decade, mysterious dark and light structures, "spokes," appear on the largest of Saturn's rings. Their nature remains a complete mystery, but recently the Hubble telescope recorded the beginning of another "spokes" season. Now astronomers will follow them with special attention.
In the ring system of Saturn's brightest and widest - ring B. Back in the 1970s, astronomers noticed that from time to time it begins to appear "spokes" - the radial structure, slightly lighter or darker than the ring itself, which appear and disappear in a matter of hours. They are observed for several years, reaching a maximum during the local equinoxes, spring and summer, and then disappear.
The closest of them will come to Saturn May 6, 2025, and the Hubble Space Telescope has already noticed the onset of the next "season of spokes. It is told in a new article by American astronomers, published in the journal Geophysical Research Letters. According to Amy Simon (Amy Simon) and her co-authors, scientific program Hubble OPAL, which is dedicated to studying the atmospheres of distant planets in the solar system, will allow a closer look at this mysterious phenomenon.
In fact, the nature of the "spokes" of the B ring remains unclear. Until now it is impossible even to predict the moment at which they begin to appear or "dissolve" finally. As Amy Simon noted, "it is also impossible to know in advance exactly when the first thunderstorm of the rainy season will happen. It is not known whether such "spokes" occur in other rings of Saturn and in rings around other planets. Perhaps the new Hubble observations will help to answer these questions and finally explain why these things happen.
Some hypotheses explain the appearance of "spokes" with collisions of the B ring with micrometeorite clouds. However, the more popular version that connects them with the magnetic field of Saturn. The magnetosphere of the giant planet is not only strong, but also erratic. Probably, during certain periods of orbital motion due to complex interactions with the solar wind it directly affects ring B. This may cause magnetization of the smallest particles of the ring, causing them to rise above or descend below its plane.