Since Saturn was smaller than Jupiter, it cooled down more quickly. Astronomers think that once its outer atmosphere reached about 15 K, helium condensed into droplets that fell towards its core.
The friction from these droplets heated up the planet to the point that it gives off roughly 2. The solar wind swept away lighter elements, such as hydrogen and helium, from the closer regions, leaving only heavy, rocky materials to create terrestrial worlds.
But farther away, the solar winds had less impact on lighter elements, allowing them to coalesce into gas giants such as Saturn.
In this way, asteroids , comets , planets, and moons were created. The composition of Saturn is almost completely the light gas hydrogen, with a significant part of it also composed of helium. Small traces of other elements exist in Saturn's atmosphere , as well. In order to capture these gases, Saturn needed to form its massive core quickly.
The massive core could then gravitationally capture the lighter elements before solar winds swept them away. Like Jupiter, Saturn is made mostly of hydrogen and helium. Its volume is times greater than that of Earth. Winds in the upper atmosphere reach 1, feet meters per second in the equatorial region.
In contrast, the strongest hurricane-force winds on Earth top out at about feet, or meters, per second. These superfast winds, combined with heat rising from within the planet's interior, cause the yellow and gold bands visible in the atmosphere. Saturn's ring system is the most extensive and complex in the solar system, extending hundreds of thousands of kilometers from the planet.
They also found "braided" rings, ringlets, and "spokes," dark features in the rings that circle the planet at different rates from that of the surrounding ring material. Material in the rings ranges in size from a few micrometers to several tens of meters, and the size and structure of the rings are partly a product of the gravitational influenceof several of Saturn's moons, known as "shepherd moons.
Saturn has 52 known natural satellites , or moons, and there are probably many more waiting to be discovered. Saturn's largest satellite, Titan, is a bit bigger than the planet Mercury. Titan is the second-largest moon in the solar system; only Jupiter's moon Ganymede is bigger. Titan is shrouded in a thick, nitrogen-rich atmosphere that might be similar to what Earth's was like long ago.
Further study of this moon promises to reveal much about planetary formation and, perhaps, about the early days of Earth. Saturn also has many smaller "icy" satellites. From Enceladus, which shows evidence of recent and ongoing surface changes, to Iapetus, with one hemisphere darker than asphalt and the other as bright as snow, each of Saturn's satellites is unique.
Though Saturn's magnetic field is not as huge as Jupiter's, it is still times as powerful as Earth's. Saturn, the rings, and many of the satellites lie totally within Saturn's enormous magnetosphere, the region of space in which the behavior of electrically charged particles is influenced more by Saturn's magnetic field than by the solar wind.
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. Like many, he considers it fortunate that humanity and the rings coexist — giving us plenty of opportunity to argue about the secrets they hold. This article was reprinted on Wired.
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