Planet Saturn

The planet Saturn is the second largest in the solar system. It is the sixth in order from the sun. It is named after the Roman god of agriculture. Because it is the farthest planet we can see with the 'naked eye' in the night sky, for a long time, scientists thought it was the last planet.

Like Neptune and Jupiter, it has no solid surface. The atmosphere consists mainly of hydrogen and helium. Since it has no solid surface, it is called a gas giant, along with Jupiter, Uranus, and Neptune. It is much farther away from the sun than Earth. Earth orbits the sun at 93,000,000 miles. Saturn moves around the sun at 887,000,000 miles. Saturn's largest storms appear in its northern hemisphere every twenty to thirty years. They appear as white spots. The strongest one was in 2011. It spread all over the planet.

There is a wide band of rings around Saturn. They stretch across 298,000 miles. Galileo observed them first in 1610 using the newly invented telescope. He thought that they might be moons on either side of the planet. In the 1650's, Christiaan Huygens realized that what they saw were rings.

The rings are brighter than the planet. They are particles that orbit the planet. Saturn's gravity prevents them from joining to form a moon. Probably the pieces are the remains of a small moon or asteroid from years ago. Small moons are found in the gaps between the rings.

Three rings can be seen from Earth. They are called A, B, and C. Giovanni Cassini saw the gap between rings A and B in 1675. More rings have been discovered recently. D ring is the closest one to Saturn. E, F, and G are farther away since they are beyond A. The bits which make up the rings range in size from giant boulders to small grains. In 2009, a new ring was discovered. It is the largest one in the solar system.

These bits and pieces in the rings are made of ice the color of dirty water. Each particle follows its own orbit. They all rotate around the planet's equator. These icy particles make it easy to see the rings because they reflect sunlight. As the planet orbits the sun, a different view of Saturn appears. It orbits the sun every twenty-nine and one-half years. As it moves in its orbit, more and more of the southern hemisphere is seen.

Saturn has 62 moons. The bigger ones orbit close to the planet. The smallest moons orbit up to 15,000,000 miles away. Titan is the biggest moon. It was discovered by Christiaan Huygens in the 1650's. It is the second largest in the solar system and bigger than the planet Mercury. It is the only moon in the solar system which has liquid seas and lakes. Its three large seas are close to its north pole. Its atmosphere appears as orange-red clouds.

The Cassini spacecraft began exploration to Saturn in 1997. It studied the planet and its moons. It returned to Earth in September 2017. The spacecraft sent its Huygens probe to land on Titan in 2005. Much of the information gained from over twenty years of studies and measurements will help scientists when the Europa Clipper launches in the 2020's.

The Europa Clipper mission will study Jupiter and its moon Europa and use the information gathered in studying Saturn and its moon Titan. Interest is building up in sending out a mission to study Saturn's atmosphere also.