Saturn: Quick Facts
Planetary Properties of Saturn
Orbital Semimajor Axis: 9.54 Astronomical Units (1,427 Million Kilometers)
Orbital Eccentricity: 0.054
Perihelion: 9.02 Astronomical Units (1,349 Million Kilometers)
Aphelion: 10.05 Astronomical Units (1,504 Million Kilometers)
Mean/Average Orbital Speed: 9.65 Kilometers Per Second
Sidereal Orbital Period: 29.42 Years (Tropical)
Synodic Orbital Period: 378.09 Days (Solar)
Orbital Inclination to the Ecliptic: 2.49 Degrees
Greatest Angular Diameter (As Viewed From Earth): 21”
Overall Mass: 5.68 x 1026 Kilograms (95.16 of Earth’s Overall Mass, if Earth = 1)
Equatorial Radius: 60,268 Kilometers (945 of Earth’s Equatorial Radius, if Earth = 1)
Mean/Average Density: 0.687 Kilograms Per Meter Cubed (0.125 of Earth’s Average Density, if Earth = 1)
Surface Gravity: 10.4 Meters Per Second Squared (1.07 of Earth’s Surface Gravity, if Earth = 1)
Escape Speed/Velocity: 35.5 Kilometers Per Second
Sidereal Rotation Period: 0.45 Days (Solar)
Axial Tilt: 26.73 Degrees
Surface Magnetic Field: 0.67 of Earth’s Magnetic Field (Assuming Earth = 1)
Magnetic Axis Tilt (Relative to Rotation Axis): 0.8 Degrees
Overall Surface Temperature: 97 Kelvin (-285.07 Degrees Fahrenheit)
Number of Moons: 62 in Total (18 Moons that are at least 10 kilometers in diameter)
Quick Facts About Saturn
Quick Fact #1: The planet Saturn is the sixth planet in our solar system, as well as the most distant planet that can be seen with the naked eye. Saturn is the second largest planet in our solar system (after Jupiter), and is composed primarily of gases which include methane, helium, hydrogen, ammonia, and ethane, to name only a few. Despite the planet’s massive size, it is actually the least dense planet in our solar system, at only 0.687 kilograms per cubic meter.
Quick Fact #2: In addition to being a very large planet, Saturn is also exceptionally flat when compared to other planets in the solar system. Due to its rapid rotation, the planet takes on a “flattened” appearance, particularly along the equatorial regions. To put Saturn’s rotational speed into perspective, one day on the planet is equal to ten hours and fourteen minutes (the second shortest day cycle for any planet in the solar system).
Quick Fact #3: Scientists have discovered 62 moons that orbit Saturn (so far). Most of these moons are quite small. However, Saturn’s moon, “Titan,” is quite large (the second largest in the solar system). Because only four spacecraft have visited Saturn so far, scientists remain uncertain as to how many planets Saturn actually has. NASA’s Cassini spacecraft is the last orbiter to pass by the gas giant in recent years. As such, it is likely that additional moons will be discovered in the years and decades that lie ahead.
Quick Fact #4: Perhaps the most well-known feature of the Saturn is its extensive ring system that stretches more than 120,000 kilometers away from the planet itself. The rings are incredibly thin, at only 20 meters thick, and are composed primarily of ice and dust. Astronomers remain uncertain as to how the rings around Saturn originated. Some scientists believe that the ring-system is quite old (perhaps 4.54 billion years old). Others, however, speculate that the rings may have formed a lot more recently. Regardless of their age, however, scientists believe that the rings were created primarily by a moon-like object that was destroyed by the gravitational pull of Saturn.
Quick Fact #5: Scientists believe that Saturn’s interior is similar to Jupiter’s composition, and have divided the planet into three different layers. The innermost layer is believed to be a solid core that is surrounded by a layer of liquid hydrogen. Scientists believe that the outer layers are composed primarily of molecular hydrogen.
Additional Fun Facts About Saturn
Fun Fact #1: Saturn was named after the Roman god, who was also the father of Jupiter. Scholars believe that the planet was first discovered by the Assyrians during the eight-century BC. During the early 1600s, Galileo became the first astronomer to observe Saturn’s ring-system; although, at the time he believed them to be large moons orbiting the planet. It wasn’t until 1655 that the Dutch astronomer, Christian Huygens, was able to categorically reject this hypothesis with the use of a higher-resolution telescope. Huygens not only discovered that Saturn possessed an intricate ring-system, but was also able to discover Saturn’s largest moon, Titan.
Fun Fact #2: Ironically, scientists have discovered that Saturn gives off more energy than it receives from the Sun. Scientists believe this is the result of gravitational compression, and the large quantity of helium that is found within Saturn’s atmosphere.
Fun Fact #3: Although Saturn has one of the fastest days of any planet in the solar system, it takes nearly 29.4 years for it to complete one orbit around the Sun. The Assyrians were one of the first civilizations to recognize the planet’s slow movement, and nicknamed Saturn “Lubadsagush,” which means “oldest of the old.”
Fun Fact #4: Saturn has some of the fastest winds in the solar system. These strong winds have been measured at speeds of nearly 1,800 kilometers per hour (approximately 1,100 miles per hour). Even the most powerful storms on Earth pale in comparison to the winds experienced on Saturn. Only the planet Neptune has winds that exceed that of Saturn.
Fun Fact #5: Similar to Jupiter’s “Great Red Spot,” Saturn also possesses spots around its poles that are believed to be giant storm systems. The largest spot currently hovers over Saturn’s south pole, and is believed to be a giant storm similar to that of a hurricane.
Fun Fact #6: Although scientists have ruled out the possibility of life on Saturn (due to its extreme atmosphere), astronomers believe that one of the planet’s moons, known as Enceladus, could possess lifeforms due to the presence of liquid water beneath its surface. Scientists became aware of this following NASA’s Cassini flyby. The orbiter discovered numerous ice geysers on Enceladus that were ejecting water vapor around the moon’s southern pole; indicating the presence of large amounts of water beneath its surface. If this is true, scientists believe that the liquid forms of water may also possess life.
“Saturn itself is a giant planet, and there’s much to be gained by investigating its meteorology and studying its magnetic field.”— Carolyn Porco
Quotes About Saturn
Quote #1: “Saturn itself is a giant planet, and there’s much to be gained by investigating its meteorology and studying its magnetic field.” -- Carolyn Porco
Quote #2: “Every type of ring behavior we have seen around Jupiter, Uranus, or Neptune can be found in orbit around Saturn. And Saturn’s ring system offers the greatest promise of understanding processes in operation within all disk systems, not just those found around planets.” -- Carolyn Porco
Quote #3: “As a planetary system, Saturn holds the greatest promise for answering questions that have a far broader scientific reach than Saturn itself.” -- Carolyn Porco
Quote #4: “I still remember the first time I pointed the telescope at the sky and I saw Saturn with the rings. It was a beautiful image.” -- Umberto Guidoni
Saturn's Ring System
Saturn’s rings are the most recognizable feature of the large gas-giant. The rings span from 6,630 kilometers to 120,700 kilometers (4,120 to 75,000 miles, respectively) away from Saturn’s equatorial zones. Scientists believe that the rings are composed primarily of ice, rock, and dust. Although some scientists believe that the rings formed from the debris of a destroyed moon, a secondary hypothesis suggests that the rings may have resulted from leftover nebular material (the same material that resulted in the formation of Saturn as a planet).
Two of Saturn’s moons, Pandora and Prometheus, are known collectively as “Shepherd Moons” as their orbit helps to maintain the circular pattern of the planet’s ring-system, and prevents dust and ice from spreading further away from the rings themselves. Altogether, Saturn has four primary groups of rings, along with three more faint groups of rings (each of which are separated by divisions).
Do you believe that Saturn's moon, Enceladus, contains life?
In closing, Saturn remains one of the most fascinating objects to observe in our solar system, given its complex structure, unparalleled beauty, and its intricate collection of rings and moons. As more and more spacecraft, probes, and orbiters are launched to study the planet in the years and decades to come, it will be interesting to see what new information can be learned about the planet, its origins, and function within our solar system. What secrets does Saturn continue to hold? Does its moons contain lifeforms not yet seen on Earth? Finally, and perhaps most importantly, what can Saturn tell us about the origins of our solar system, galaxy, and universe at large?
Wikipedia contributors, "Saturn," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/w/index.php?title=Saturn&oldid=877108056 (accessed January 14, 2019).
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© 2019 Larry Slawson