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Astronomers have long believed that Saturn distinctive ring It formed around the same time as the planets, early in the solar system about 4.5 billion years ago. The assumption is that serious challenge from 2019 analysis Much of the data collected by NASA’s Cassini spacecraft suggests that the rings are only 10 to 100 million years old, or just a blink of an eye on the cosmic timescale. A new analysis of data on how much dust is accumulating on the ring confirms a controversial finding, according to a report. new paper It was published in Science Advances.
“In a way, the question that started with James Clerk Maxwell has come to an end.” Co-author Sascha Kemp said:, an astronomer at the University of Colorado, Boulder. In 1610 Galileo observed the rings for the first time, but his telescope was too crude to confirm that they were real rings. He described them as “Saturn’s Ears” because they looked like his two smaller planets on either side of Saturn. Galileo was baffled when the “ears” disappeared in 1612 as the Earth passed through the ring plane, and was even more baffled when they reappeared the following year.
Christopher Wren suspected that Saturn had rings in 1657, but Christian Huygens pushed him aside and published a paper in 1659 suggesting that the rings were separated from Saturn. system saturnium, also mentioned the discovery of Saturn’s moon Titan. Robert Hook noticed a shadow on the ring. By 1675, Giovanni Cassini discovered that the ring was a series of smaller rings with gaps between them. More than a century later, Pierre-Simon Laplace mathematically proved that rings in solids are unstable. Maxwell determined that the “ring” must consist of many small particles, all independently orbiting Saturn, confirmed by observations in 1859. We now know that those particles are composed almost entirely of water ice.
The space age has made it possible to send probes to explore the solar system, and Pioneer 11, Voyager 1, and Voyager 2 have all returned increasingly detailed images of ringed planets.And in 1997 NASA Cassini spacecraft, a joint venture with the European Space Agency to explore Saturn, its moons and its ring system. Cassini spent 13 years orbiting the gas giant, and just for that, it provided stunning images of unprecedented resolution and many scientific insights, including evidence such as: So-called “ring rain” Upon falling to Earth, the ring could gradually disappear within 100 million years.
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Among the instruments on board Cassini is a space dust analyzer, whose data show that the ring is slowly but steadily being contaminated by a mixture of rock dust and other organic compounds, most of which are from the Kuiper belt. It was shown to come from micrometeorites. “Think of the ring like the carpet in your house.” Kempf said.. “If you have a clean carpet, then you just have to wait. Dust accumulates on the carpet, and so do the rings.” Water ice in Saturn’s rings is 4.5 billion years old. Related to this is one of the arguments about young age, which is surprisingly bright and pure for a putative structure. It should be darker because of the accumulated dust layer.
During its epic “grand finale” in 2017, Cassini performed 22 dives between Saturn and its rings, allowing scientists to extract the masses of both before the rover died violently in the gas giant’s atmosphere. I was able to decide. This Cassini data was used as a reference for research by Luciano Yel of Sapienza University in Rome and his co-authors. 2019 paper Because it allows us to know the amount of soot on the tree rings, its rate of fall, and the age of the dust. The researchers concluded that the rings appeared at a time when dinosaurs were still roaming the Earth, not 100 million years ago. This vivid detail has garnered thousands of headlines and helped cement the concept in the public imagination. They also found that Saturn’s B ring is large enough to dilute falling dust, which would explain the relative purity of the ice particles.
The result is met with skepticism Some people think so, given the many uncertainties. Among the skeptics was Aurélien Clida, a planetary scientist at the Côte d’Azur Observatory. announced an objection to Aiel other. It was published later that year in Natural Astronomy. To explain the lack of dust accumulation on the rings, Clida suggested that some sort of planetary ‘scrubber’ might preferentially remove dust from the rings through ring rain. . Cassini’s data showed that this rain contained only 24% ice for him, while the ring itself was 95% ice for him. Crida discovered a possible candidate for this scrubbing mechanism in a 2017 paper by Kemp’s group (published in the same issue of Science), noting the presence of nanoparticles coalescing from the main rings flowing into Saturn. bottom.
