Cassini measured the rain using two separate instruments. Crida said that perhaps the ice ejected by micrometeoroid impacts tends to reattach itself to the rings, while the ejected pollutants rain out. Becker conjectures that pollution is being preferentially ejected by impacts, regardless of whether the ice is reattaching itself in this manner.
But no one knows for sure. What if, said Crida, the pollution argument is correct? What if the rings have always been exposed to an unchanging influx of cosmic dust, and the rings are million years old at most? Then we would have to explain how the rings formed so recently, which is a tricky prospect. First, we have no idea what created the rings, so assigning them an origin story at any point in time is difficult. But no such mission is forthcoming.
The typical thickness of the rings is only about 10 meters. But their own stories are also riddled with uncertainties, from their origins to their ages. A model , using the current positions of the moons to peer backward through time, suggests that the present system of rings and inner moons could have been created when a pair of midsize moons smashed into each other about million years ago.
While the past is unclear, the future seems more certain. The rings may look permanent, but the opposite is true. When scientists add this to the material detected by Cassini, they estimate that the rings will disappear completely in million years. Aurorae occur when charged particles spiral into a planet's atmosphere along magnetic field lines. On Earth, these charged particles come from the solar wind. Cassini showed that at least some of Saturn's aurorae are like Jupiter's and are largely unaffected by the solar wind.
Instead, these aurorae are caused by a combination of particles ejected from Saturn's moons and Saturn's magnetic field's rapid rotation rate.
But these "non-solar-originating" aurorae are not completely understood yet. Introduction Saturn is the sixth planet from the Sun and the second-largest planet in our solar system. Namesake Namesake The farthest planet from Earth discovered by the unaided human eye, Saturn has been known since ancient times.
Potential for Life Potential for Life Saturn's environment is not conducive to life as we know it. Size and Distance Size and Distance With a radius of 36, A 3D model of Saturn, the ringed gas giant planet. This page showcases our resources for those interested in learning more about Saturn and Titan.
Saturn and Titan Resources. JPL's lucky peanuts are an unofficial tradition at big mission events. Full Moon Guide: October - November A new paper details how the hydrological cycle of the now-dry lake at Jezero Crater is more complicated than originally thought. This year, the minimum extent of Arctic sea ice dropped to 1. The lander cleared enough dust from one solar panel to keep its seismometer on through the summer, allowing scientists to study three big quakes. Researchers will use Webb to observe 17 actively forming planetary systems.
Scientists found evidence that an area on Mars called Arabia Terra had thousands of "super eruptions" over a million-year period. Full Moon Guide: September - October Perseverance successfully collected its first pair of rock samples, and scientists already are gaining new insights into the region. Data received late Sept. That's the distance from the Earth to the Moon! But the rings are as little as meters feet thick.
They range from particles too tiny to see to "particles" the size of a bus. Scientists think they are icy snowballs or ice covered rocks. Artist's concept of Cassini diving between Saturn and its innermost ring. The Cassini spacecraft arrived at Saturn in July It orbited Saturn for 13 years, studying Saturn, its rings, and its moons much more thoroughly than the earlier spacecraft could.
As heavenly bodies converge, many ask: Is the Star of Bethlehem making a comeback? By Jove! Saturn pairs up with Jupiter to create "Christmas Star" on winter solstice.
The Star of Bethlehem: Can science explain what it really was? Cosmos: Origin and Fate of the Universe. Astronomy's Moon Globe. Galaxies by David Eicher. Astronomy Puzzles.
Jon Lomberg Milky Way Posters. Astronomy for Kids. Sign up. Table of Contents Subscribe Digital Editons. A chronicle of the first steps on the Moon , and what it took to get there. The Magazine News Observing. Photos Videos Blogs Community Shop. Sign up!
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