Credit: NASA, ESA, STScI, Amy Simon (NASA-GSFC)Levitated Dust Takes a Carousel Ride Around the Giant RingworldThough Saturns unusual-looking “cup deal with” features were first kept in mind by Galileo in 1610, it would be another 45 years before they were described by Christiaan Huygens as a disk surrounding Saturn. Credit: NASA, ESA, STScI, Amy Simon (NASA-GSFC)Hubble Space Telescope Watches Spoke Season on SaturnThis picture of Saturn was taken by NASAs Hubble Space Telescope on October 22, 2023, when the ringed planet was approximately 850 million miles from Earth. Hubble continues observing Saturn each year as the spokes go and come.”The leading theory is that spokes are tied to Saturns effective magnetic field, with some sort of solar interaction with the magnetic field that offers you the spokes,” stated Simon. In this setup, the solar wind may more strongly damage Saturns tremendous magnetic field, enhancing spoke formation.Planetary scientists believe that electrostatic forces generated from this interaction levitate dust or ice above the ring to form the spokes, though after numerous decades no theory perfectly predicts the spokes.
This picture of Saturn was taken by NASAs Hubble Space Telescope on October 22, 2023, when the ringed planet was roughly 850 million miles from Earth. Hubbles ultra-sharp vision exposes a phenomenon called ring spokes.Saturns spokes are short-term features that turn in addition to the rings. Their ghostly look just persists for 2 or three rotations around Saturn. During active periods, freshly-formed spokes continually add to the pattern. Credit: NASA, ESA, STScI, Amy Simon (NASA-GSFC)Levitated Dust Takes a Carousel Ride Around the Giant RingworldThough Saturns unusual-looking “cup deal with” features were first kept in mind by Galileo in 1610, it would be another 45 years before they were explained by Christiaan Huygens as a disk surrounding Saturn. Subsequently, ground-based telescopes could just distinguish four distinct concentric rings, identified A, B, C, and D. Not till the 1980s did NASAs 2 Voyager probes fly by Saturn to photo thousands of concentric curls. An even larger surprise to Voyager researchers were dark, radial spoke-like patterns in the ring airplane that went and came as they revolved around Saturn.Over the previous three years, the Hubble Space Telescope has gotten where the Voyagers have left off. Hubbles ultra-sharp vision is the next best thing to being there. Hubble follows the ring spoke “merry-go-round” every year. Its believed the dark spokes are dust particles electrostatically levitated above the ring airplane. They appear to alter in abundance with Saturns seven-year-long seasons. And, this might be connected to changes in Saturns electromagnetic field, as it is battered by the solar wind.This is an annotated version of the image above. Credit: NASA, ESA, STScI, Amy Simon (NASA-GSFC)Hubble Space Telescope Watches Spoke Season on SaturnThis image of Saturn was taken by NASAs Hubble Space Telescope on October 22, 2023, when the ringed planet was around 850 million miles from Earth. Hubbles ultra-sharp vision exposes a phenomenon called ring spokes.Saturns spokes are transient functions that turn in addition to the rings. Their ghostly look only continues for 2 or 3 rotations around Saturn. Throughout active periods, freshly-formed spokes continuously contribute to the pattern.In 1981, NASAs Voyager 2 very first photographed the ring spokes. NASAs Cassini orbiter likewise saw the spokes throughout its 13-year-long objective that ended in 2017. Hubble continues observing Saturn every year as the spokes go and come. This cycle has actually been captured by Hubbles Outer Planets Atmospheres Legacy (OPAL) program that began nearly a years back to annually keep an eye on weather changes on all 4 gas-giant outer planets.Hubbles crisp images reveal that the frequency of spoke apparitions is seasonally driven, initially appearing in OPAL information in 2021 but only on the morning (left) side of the rings. Long-lasting tracking reveal that both the number and contrast of the spokes vary with Saturns seasons. Saturn is tilted on its axis like Earth and has seasons lasting around seven years.”We are heading towards Saturn equinox, when we d expect maximum spoke activity, with higher frequency and darker spokes appearing over the next few years,” stated the OPAL program lead researcher, Amy Simon of NASAs Goddard Space Flight Center in Greenbelt, Maryland.This year, these ephemeral structures appear on both sides of the planet concurrently as they spin around the giant world. They look small compared with Saturn, their length and width can extend longer than Earths size!”The leading theory is that spokes are tied to Saturns powerful magnetic field, with some sort of solar interaction with the electromagnetic field that gives you the spokes,” said Simon. The world and its rings are less slanted away from the Sun when its near the equinox on Saturn. In this setup, the solar wind might more strongly batter Saturns enormous magnetic field, enhancing spoke formation.Planetary scientists think that electrostatic forces produced from this interaction levitate dust or ice above the ring to form the spokes, though after several decades no theory completely forecasts the spokes. Continued Hubble observations may ultimately help solve the mystery.The Hubble Space Telescope is a job of worldwide cooperation between NASA and ESA. NASAs Goddard Space Flight Center in Greenbelt, Maryland, handles the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, carries out Hubble and Webb science operations. STScI is run for NASA by the Association of Universities for Research in Astronomy, in Washington, D.C.