The modern astronomy has gifted us with the great pleasure of knowing our far-off planetary neighbors with more details than ever before. Whether it’s Jupiter’s intimidating Great Red Spot or Saturn’s mesmerizing planetary rings, we now have much better understandings of outer planets in our solar system than anytime else in the entire human history staring from the ancient Babylonians and Chinese.
Today we will reveal much more about the planet Saturn, possibly more than you may know. For starters, Saturn is the second largest planet in our solar system and sixth from the Sun. It is named after the Roman god of agriculture. In many ways, Saturn is similar to Jupiter, but there are many more things about Saturn that you should know. Here are some of the facts about about Saturn.
First Known Observation: By the Ancient Babylonians
Equatorial Diameter: 120,536 km
Orbital Period: 29.5 years
Satellites or Moons: 62 Known Moon
Mass: 5.6834×1026 kg
Density: 0.687 g/cm3
Surface Gravity: 10.44 m/s2
Image Courtesy: NASA
Do you Know that almost 1,600 Saturn can Fit inside the Sun? Now that you know, can you guess how many Earths can fit inside the Sun? The answer is roughly 1.3 million Earths.
14. Chemical Composition
Just like its gaseous neighbor Jupiter, Saturn also has a small rocky core surrounded by mainly hydrogen and Helium. Its inner core is much denser than most of the planets in our solar system with the mass as much as 22 times higher than that of the planet Earth.
Despite the fact that most of its atmosphere is composed of hydrogen and helium, a large amount of Saturn’s mass is actually not in gaseous phase. Traces of other gases like methane, ammonia, hydrogen deuteride and ethane are also found in its atmosphere similar to Jupiter.
13. Physical characteristics
Saturn is the second largest planet in our solar system only after Jupiter. While it has one-eighth of the total density of the Earth, its mass is more than 95 times of the Earth’s and 90 times of its radius. The planet is perhaps famous for its distinguishable, and complex ring system.
Yellow and orange bands of different shades on Saturn’s atmosphere is due to the ultra-fast winds along with the planetary heat flowing in its upper atmosphere. Right now nearly 62 moons are identified orbiting around the planet of which 53 are officially named.
12. Rotation & Orbit
The estimated distance between the Sun and Saturn is about 9AU or 1.4 billion in kilometers. Compared to the Earth, it takes about 29.5 years to complete one rotation around the Sun. Saturn has the second fastest rotation (on its axis) after Jupiter completing one in every 10 hours and 30 minutes. There is a slight difference of several minutes in this rotational speed due to the phenomena of differential rotation which is effective on the planet.
11. It’s Visible in the Night Sky
With a bond albedo of 0.342, Saturn is the fifth brightest the farthest planet we can see with our bare eyes, while telescopes are needed to observe some of its features such as its planetary rings. The far reaches of Saturn are the limit of human eyes. Many times over the course of a year, the planet presents itself slightly brighter than the star Antares.
10. The Planet Was Well Known to the Ancient Babylonians
Saturn has been known to humans since the prehistoric times. The ancient Babylonians were probably the first to observe and record its movements. Early Greeks to their god Cronus while the Romans dedicated the planet to Saturnus, their god of agriculture after which the planet was named. One of the first scientific calculations of its Orbit was performed by Ptolemy when Saturn was in opposition.
9. Saturn is the flattest planet
Saturn is perhaps the flattest planet (near the poles) in the solar system and that’s due to its very low density and relatively higher rotational speed. The planet takes a peculiar shape of a spheroid, which is much flattened at the poles.
8. Bands of Clouds
Image Courtesy: NASA
Saturn’s atmosphere exhibits a banded pattern similar to Jupiter’s, but Saturn’s bands are much fainter and are much wider near the equator. The nomenclature used to describe these bands is the same as on Jupiter. Saturn’s finer cloud patterns were not observed until the flybys of the Voyager spacecraft during the 1980s. The top layers are mostly ammonia ice. Below them, the clouds are largely water ice. Below are layers of cold hydrogen and sulfur ice mixtures.
7. Saturn’s Magnetic Field is Weaker than Earth’s
Unlike Jupiter, Saturn’s magnetic field is much simpler and symmetric in shape. Near its equator, the strength of its magnetic field is around 0.2 Gauss, which is weaker than that of the Earth’s and about one-twentieth that around the planet Jupiter. It is believed that the magnetic field around the planet is generated by the currents from the liquid metallic-hydrogen layer near its core. Even though weak, its magnetosphere is effective in deflecting solar winds coming from the Sun.
6. It’s Second Largest Moon Rhea
Rhea was first discovered by Giovanni Cassini during his observation of Saturn in 1672. It is the second largest moon of Saturn and ninth largest in the entire solar system. Back in 2005, scientists hypothesized the existence of a small ring system, which, if proven will make Rhea the first natural satellite to have its own ring system. But numerous observations done by NASA’s Cassini spacecraft on the icy moon resulted in nothing.
Then again in 2010, NASA revealed the discovery of a weak exosphere around the moon for the first time. This exosphere is mainly composed of carbon dioxide and oxygen in a ratio of 2 to 5. Scientists believe that the oxygen present in the moon’s atmosphere is a result of radiolysis of water ice by the ions present Saturn’s magnetosphere. While the source of carbon dioxide is rather not clear, but its maybe due to some organics present in Rhea’s surface.
5. Eerie Sounds of Saturn’s Radio Transmission
Saturn has been long known as a prominent source of radio emissions in our solar system. But in 2002, Cassini spacecraft detected mysterious radio emissions originated from Saturn’s poles for the first time from about 380 million kilometers from the planet. According to NASA, these eerie sounds are somehow closely related to the auroras near the poles of the planet. These radio emissions were only audible to human ears after they were downsized by the factor of 44.
4. Saturn’s Moon Titan
Titan is the second largest moon in our solar system after Jupiter’s Ganymede and it’s the largest of all 62 known moons of Saturn. Titan is not just larger than most of the moons, but it also outsize Mercury, the smallest planet revolving around the Sun. Due to its special characteristics, Titan is sometimes classified as a planet-like moon.
Its dense Nitrogen-rich atmosphere is somehow similar to that of our Earth. In 2004, data collected by the Cassini spacecraft indicated that the moon might be “super-rotator“, where the atmosphere rotates at much faster rates than the surface. It also features a vortex near its south pole.
3. Cloud Patterns and Vortexes
Saturn’s rather famous hexagon cloud pattern was first detected in 1981 by the two Voyager probes and was again visited by NASA’s Cassini spacecraft in 2006. The enormity of Saturn’s hexagon can be estimated by the fact that each of its sides is approximately 14,000 km long and rotates once in a period of 10 hours 39 minutes and 24 seconds.
Saturn also has a giant vortex near its south pole which was first observed by the Hubble space telescope, but various data shows that it is not a strong polar vortex nor any kind of standing wave like the one on the north pole. According to NASA, this polar vortex may have been there for the last few billion years. There is a second vortex inside the northern hexagon.
2. Saturn’s Iconic Rings
From Jupiter to Neptune, all of the gas giants in our solar system have rings, but Saturn’s are the brightest and significant of all. Although they were first discovered by Italian genius Galileo Galilei in the early 1600s, the first detailed study of these rings was made by Christiaan Huygens in 1655. He also discovered of Saturn’s largest moon Titan. Saturn’s rings stretch from about 6,600 km to 120,700 km from its equator. They are predominantly composed of water with small traces of tholin and amorphous carbon.
1. Recent Researches and Explorations
900 million miles far, Earth shines bright among the many stars. Image Courtesy: NASA
We were able to get close-up images of Saturn for the first time in 1979, when NASA’s Pioneer 11 reached within less than 22,000 km of the planet. That encounter revealed presence of a strong magnetic field and also two of its outer rings. Then the planet was again visited by the Voyagers in 1980-81, and this time we were able to get better images of the gas giant. The probes also discovered some of its new moons.
After the Voyagers, Cassini was the only space probe, which studied the planet in detail. Before its demise, Cassini was able to collect tons of valuable data like the liquid water deposits on Saturn’s Enceladus and detailed images of Phoebe, one of its moons and Titan. In the case of Titan, it was able to take some unique images of lakes and mountains on that moon for the first time.