This photo of Saturn was taken by NASA’s Hubble Space Telescope on , when the ringed planet was about 850 million miles from Earth. Hubble’s razor-sharp vision reveals a phenomenon called ring spokes.
Saturn’s spokes are temporary features that rotate with the rings. Their ghostly appearance only lasts for two or three revolutions around Saturn. During the active period, newly formed spokes continually add to the pattern.
Floating Dust rides a merry-go-round around a huge ring world
However Saturn
Its unusual-looking “cup-handle” feature was first noted by Galileo in 1610, but it took another 45 years before it was described by Christian Huygens as a disk surrounding Saturn. Ground-based telescopes were then able to identify only four unique concentric circles, labeled A, B, C, and D. It could not be identified until the 1980s. NASA
The two Voyager spacecraft will fly close to Saturn and photograph thousands of concentric ringlets. An even bigger surprise for Voyager scientists was the dark, radial, spoke-like pattern on the ring’s surface that moved back and forth as it orbited Saturn.
Over the past 30 years, hubble space telescope Voyager picked up where it left off. Hubble’s ultra-clear vision is the next best thing to being there. Hubble follows a “merry-go-round” of ring spokes every year. The black spokes are believed to be dust particles suspended by static electricity above the ring surface. They seem to vary richly depending on the seasons of Saturn’s seven years. And this may be related to changes in Saturn’s magnetic field, which is influenced by the solar wind.
Hubble Space Telescope observes Saturn’s ‘spokes season’
This photo of Saturn was taken by NASA’s Hubble Space Telescope on , when the ringed planet was about 850 million miles from Earth. Hubble’s razor-sharp vision reveals a phenomenon called ring spokes.
Saturn’s spokes are temporary features that rotate with the rings. Their ghostly appearance only lasts for two or three revolutions around Saturn. During the active period, newly formed spokes continually add to the pattern.
In , NASA’s Voyager 2 took the first photo of a ring spoke. NASA’s cassini The orbiter also sighted spokes during its 13-year mission, which ended in 2017.
Hubble continues to observe Saturn every year as its spokes come and go. This cycle is captured by Hubble’s Outer Planet Atmospheric Legacy (OPAL) program, which was launched nearly a decade ago to annually monitor weather changes on all four gas giants.
Hubble’s clear images show that the frequency of the spokes’ appearance is seasonal, and they appeared in the OPAL data for the first time in , but only on the morning (left) side of the ring. Long-term monitoring has shown that both the number and contrast of spokes change with Saturn’s seasons. Saturn’s axis is tilted like Earth’s, and its seasons last about seven years.
“We’re heading towards the Saturn equinox, when the spokes are expected to be at their most active, and will remain active for several years to come,” said Amy Simon, OPAL program principal scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We expect higher frequencies and darker spokes to appear.” .
This year, these ephemeral structures will appear on both sides of the Earth simultaneously, rotating around the giant world. Although it appears small compared to Saturn, its length and width can extend to more than Earth’s diameter.
“The leading theory is that the spokes are connected to Saturn’s strong magnetic field, and that the Sun is somehow interacting with that field to create the spokes,” Simon said. As Saturn approaches its vernal equinox, Saturn and its rings tilt less away from the Sun. In this configuration, the solar wind could hit Saturn’s massive magnetic field even harder, promoting spoke formation.
Planetary scientists believe that the electrostatic forces generated by this interaction cause the dust and ice to float above the ring, forming the spokes, but even after decades, no theory can fully predict the spokes. . Continued Hubble observations may ultimately help solve the mystery.
The Hubble Space Telescope is an international cooperative project between NASA and ESA. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts science operations for Hubble and Webb. STScI is operated for NASA by the Association of Universities for Astronomical Research in Washington, DC.
Source: scitechdaily.com
