Most of the planets revolve around the sun counter-clockwise though some of them have an erratic or steep tilt to their orbits. Even those that have a steeper tilt tend to maintain elliptical orbits. For example Pluto’s orbit sometimes places it between Uranus and Neptune. Mercury’s orbit is only seven degrees tilted on its elliptical plane.
Uranus
There are 27 satellites orbiting Uranus which are in turn surrounded by a ring system. Of the regular satellites five are more than 450 kilometers in diameter. Their small diameters and low densities suggest they are icy bodies. There are also moons that orbit Uranus but are not as large as Titania. Despite its small size Uranus is one of the most distant planets in the solar system.
Unlike other planets Uranus’ axis of rotation is almost entirely oriented in a polar direction. Its poles are located opposite to Earth’s equator. The rings of Uranus can be seen both face and edge-on and there are 13 known rings. Uranus has 27 known moons and its central rocky core takes up approximately 20% of the planet’s radius. Temperatures on the planet are similar to those found on Earth.
Venus
Earth and Venus are close neighbors but you may not know that Venus takes almost two-and-a-half years to complete one full rotation. The distance between the two planets is approximately 67 million miles which is almost one-fifth of the distance between Earth and Mars. As a result Venus has one of the least-eccentric orbits of any planet. Its orbit deviates from a perfect circle by one part in 150. The planet Venus is also the smallest of the planets and its period is roughly two and a half Earth days.
The planet Venus rotates around the Sun in a counterclockwise direction relative to the star. But at some point it flipped its axis 180 degrees. While Venus rotates in the same direction its appearance is reversed if you view it from Earth. The flip may have been caused by strong atmospheric tides or friction between the core and mantle of Venus. In any case the process has reshaped the planet.
Earth
The Earth revolves around the Sun in an elliptical orbit or a circle with a constant velocity perpendicular to the Sun’s gravitational pull. Without the Sun the Earth would travel in a straight line but the gravitational pull of the Sun forces the planets out of their natural orbits. This is how Earth travels in space – a circle. In a way Earth is similar to a star as it completes one revolution around the Sun every 365 days.
The Sun’s gravitational pull keeps the planets in predictable orbits around the sun. At certain times of the year the Earth is angled roughly 90 degrees from the plane of its orbit. This difference in angle is what allows the Earth to have the seasons it does. The bright parts of Earth get warmer and the dark parts receive colder temperatures. Because of this variation in light availability the seasons are based on the difference in the amount of sunlight that is available on the Earth’s surface.
Jupiter
How does Jupiter revolve around the Sun? Jupiter and the sun both revolve around the barycenter or the center of mass of two bodies. Jupiter and the sun move through space together but their distances are much different. Jupiter is a little over three times the mass of Earth while the latter is ten times the mass of the entire solar system. However both bodies do orbit the sun and their gravity is the same.
Earth and Jupiter both revolve around the sun and both planets wobble when close to their respective barycenters. Jupiter pulls on Earth nearly equal to its pull. While Jupiter wobbles on the Sun it rotates around the sun almost as fast as the Earth does. The moon on the other hand orbits the Earth once every month. The Earth is approximately 30 times farther from Jupiter than the Moon. In addition to this Earth has a slightly smaller mass than Jupiter.
Saturn
One of the most intriguing phenomena about Saturn is its six-sided jet stream. This phenomenon was first observed by the Voyager I spacecraft and has now been confirmed by the Cassini mission. It spans an area of about 20000 miles is made up of 200-mph winds and features a massive rotating storm at the center. Scientists believe that this phenomenon is the result of collisions between the planet’s charged particles and hydrogen in its atmosphere.
The precise rotation period of Saturn is difficult to measure because it is not a solid object. However there are cloud patterns that trace a series of periods. Clouds near the equator rotate at the fastest rate while those at the poles rotate slowly around 30 minutes per day. From this data scientists have calculated that Saturn’s day is equal to 10.5 Earth hours which is half the duration of Earth’s day.
Pluto
The planet Pluto revolves around the Sun and is the tenth largest object in our solar system. It is home to five moons the largest of which is Charon which is approximately 750 miles in diameter and 12 percent of Pluto’s mass. The two moons that have been discovered so far are Hydra and Nix. The Hubble Space Telescope has already captured photographs of the moons Pluto has in the past.
The name Pluto was first ascribed to the ninth planet in our solar system. In fact Pluto is the smallest planet in the Solar System being only about two-thirds the size of Earth’s moon. In fact scientists even attempted to reclassify Pluto as a comet in 1999. However on August 24 2006 the official classification of Pluto was changed to dwarf planet. This created a new category of objects that orbit the Sun.
Neptune
The number of moons of Neptune depends on the materials found at the place. The Kuiper Belt where Neptune lives is filled with rotating objects. These objects create essences which later become comets or icy organisms. Neptune is surrounded by at least twelve moons. Several of these moons are too small to have atmospheres. Therefore most of the moons orbit Neptune in close proximity.
As part of its orbit Neptune’s atmosphere is divided into latitudinal bands. These bands move around the planet at speeds up to 600 m/s. The resulting winds are among the fastest in the solar system. Although it’s impossible to predict when Neptune will experience a storm scientists can expect some turbulence. Voyager a spacecraft that flew by Neptune in 1989 detected atmospheric turbulence.
Saturn’s moons
There are 24 known moons of Saturn. Most are named after the Titans from Greek mythology. The moons orbit Saturn in a prograde manner not greatly inclined to the equatorial plane. They consist of seven major moons four trojan moons two moons that orbit within gaps in Saturn’s rings and two unnamed satellites. The largest moon Titan orbits near the center of Saturn’s ring system while the smaller moon Rhea is the smallest. Besides Titan the moons orbit within gaps between the rings. The moons orbit in a prograde fashion and in some cases in retrograde motion.
Titan is the largest moon of Saturn and it is the second largest in the Solar System after Pluto. Titan has a dense atmosphere composed mostly of nitrogen with a trace of methane. The atmosphere obscures the surface of Titan and its temperature is -289degC or -178degF. Hyperion is the largest irregular-shaped moon of Saturn. Its surface temperature fluctuates and its rotational period is variable.
Pluto’s moons
Charon the largest moon of Pluto has a synchronous orbit around Pluto. That means it never rises or sets on Pluto’s surface. It also rotates on its axis once for each Pluto orbit. That synchronous rotation allows Charon to cast shadows in places where the Sun cannot reach it. Pluto’s other four moons are irregularly shaped and rotate quickly and they do not appear to face the Sun.
The newest discoveries make it possible to discover details about distant stars and planets including other moons that orbit Pluto. In a computer simulation scientists have pinpointed the masses of two moons orbiting Pluto. If this happens it will lead to information about distant stars and planets that orbit two stars as it does with Pluto. In a few years NASA’s New Horizons spacecraft will be even closer to the Pluto system.
