Saturn is not the only planet to have rings, but none are as spectacular or as complex as Saturn's. Saturn also has dozens of moons. From the jets of water that spray from Saturn's moon Enceladus to the methane lakes on smoggy Titan , the Saturn system is a rich source of scientific discovery and still holds many mysteries. The farthest planet from Earth discovered by the unaided human eye, Saturn has been known since ancient times. The planet is named for the Roman god of agriculture and wealth, who was also the father of Jupiter.
Saturn's environment is not conducive to life as we know it. The temperatures, pressures, and materials that characterize this planet are most likely too extreme and volatile for organisms to adapt to.
While planet Saturn is an unlikely place for living things to take hold, the same is not true of some of its many moons. Satellites like Enceladus and Titan, home to internal oceans, could possibly support life.
With a radius of 36, If Earth were the size of a nickel, Saturn would be about as big as a volleyball. From an average distance of million miles 1. One astronomical unit abbreviated as AU , is the distance from the Sun to Earth. From this distance, it takes sunlight 80 minutes to travel from the Sun to Saturn.
Saturn has the second-shortest day in the solar system. One day on Saturn takes only Its axis is tilted by This means that, like Earth, Saturn experiences seasons.
Saturn is home to a vast array of intriguing and unique worlds. From the haze-shrouded surface of Titan to crater-riddled Phoebe, each of Saturn's moons tells another piece of the story surrounding the Saturn system. Currently, Saturn has 53 confirmed moons with 29 additional provisional moons awaiting confirmation.
Saturn's rings are thought to be pieces of comets, asteroids, or shattered moons that broke up before they reached the planet, torn apart by Saturn's powerful gravity. They are made of billions of small chunks of ice and rock coated with other materials such as dust. But cosmic clues hidden deep within the rings caused some Cassini scientists to massively revise this figure. They emerged no more than million years ago, back when dinosaurs roamed Earth. He and other skeptics have pointed out that there are a lot of potential problems with the argument, from the physics of the ring pollution to the origins of the rings themselves.
The rings were named alphabetically in the order they were discovered. In response to the hypothesis, Crida co-authored a commentary for Nature Astronomy , published in September, that presented a litany of uncertainties.
The dinosaurian age of the rings is an eye-catching claim, said Crida, but it circumvents an uncomfortable reality: Too many uncertainties exist to permit any firm estimate of the age of the rings. Proponents of the younger age stand by their work. We know the age of the Earth because we can use the decay of radioactive matter in rocks to work out how old they are.
Planetary geologists have done the same for rocks from the moon and Mars. That means age estimates have to be based on circumstantial evidence. That evidence, in part, comes from dust. Think of the icy rings as resembling a field of snow: After a pristine start, soot from afar gradually pollutes it. In order to estimate the age of the snow, scientists have to measure the rate at which soot is falling, as well as the total amount of soot already there.
Most of this material is being delivered by micrometeoroids from the Kuiper belt, a distant source of icy objects beyond the orbit of Neptune. To uncover the total mass of cosmic soot in the rings, researchers then had to weigh the rings themselves.
The rings of Saturn may be iconic, but there was a time when the majestic gas giant existed without its distinctive halo. In fact, the rings may have formed much later than the planet itself, according to a new analysis of gravity science data from NASA's Cassini spacecraft. The findings indicate that Saturn's rings formed between 10 million and million years ago.
From our planet's perspective, that means Saturn's rings may have formed during the age of dinosaurs. The conclusions of the research — gleaned from measurements collected during the final, ultra-close orbits Cassini performed in as the spacecraft neared the end of its mission — are the best answer yet to a longstanding question in solar system science.
The findings were published online Jan. Saturn formed 4. There have been clues that its ring system is a young upstart that attached to Saturn years afterward. But how long afterward? To figure out the age of the rings, scientists needed to measure something else: the mass of the rings, or how much material they hold.
Even given their mass, some researchers expect they would have dissipated away and argue for a young age. Based on this information, some researchers estimate that the rings are much younger: somewhere in the range of , to 1 billion years. But there are some additional concerns.
After all, what if the rings are old and formed with the planet, but researchers are simply overestimating how quickly they should dissipate? It may seem like an unsolvable problem, but astronomers have hope. A tiny telescope beyond Saturn might trump giant telescopes near Earth. Seeing the Great Conjunction. 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.
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