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What Are Our Planets: Online Definitive Guide

The word planet comes from the Greek word “planetes,” which means “planet.” In ancient times, people believed that planets were deities. Although the concept of a deity has since changed, our planets remain wandering the night sky. Planets need to be big enough to force themselves to a spherical shape and have enough mass that it cleared out similar sized objects in its orbit. This mass is referred to as the mass of the planet.


It’s not hard to understand why Jupiter is considered the fifth planet from the sun. With an atmosphere so thick, it could contain about 1,300 Earths. Its Great Red Spot resembles an enormous eye. Jupiter’s swirls and spots are caused by massive storms, and its prevailing winds are up to 335 miles per hour near the equator. Learn more about the different kinds of storms and spots on Jupiter.

The atmosphere of Jupiter is composed of hydrogen and helium, and it is fairly dense. This atmosphere makes the planet look like it is striped. Despite the massive size of Jupiter, its atmosphere is the same as that of the Sun. It is thought to have a rocky core deep beneath its “surface” and is very hot due to gravitational compression. Because of this, the atmosphere is too cold to support fusion reactions that would convert Jupiter into a star.

The magnetic field of Jupiter is attributed to liquid metallic hydrogen. The moon Io emits large quantities of sulfur dioxide that forms a gas torus on its orbit and becomes ionized in Jupiter’s magnetosphere. These gases cause a plasma sheet in the planet’s equatorial plane, deforming Jupiter’s dipole magnetic field. This phenomenon is similar to that of Earth’s superbolts, but it may be more complicated than what is believed.


Saturn is the least dense of all the planets in our solar system, so if it were a puddle, it would float. The planet gives off more energy than the Sun, so its atmosphere must be extremely hot. It has seven named rings, each one containing thousands of ringlets. Saturn’s day lasts approximately ten Earth hours. A spacecraft flying past the planet would experience a pressure of a billion tons, but could not land on the surface.

The visible features of Saturn rotate at different rates depending on their latitude. As a result, they are classified into different rotation periods. In fact, the visible features of Saturn rotate at different rates, as do the other planets. The rings are largely depleted, and will probably become inactive in about 100 million years. A spacecraft passing through Saturn will likely pass through these rings before the planet runs out of material to add to its atmosphere.

Besides the rings, Saturn has at least seven other moons that orbit the gas giant. Its largest, Titan, is a slightly larger moon than Mercury. Its atmosphere is overwhelmingly nitrogen-rich, which is why it is the second largest moon in our solar system after Jupiter’s moon Ganymede. Unlike Mercury, Titan is covered in a thick atmosphere that is ten times thicker than Earth’s.


You may have heard about the odd day-night cycle on Uranus. The planet is 98 degrees tilted to the sun, causing it to experience seasons with an odd day-night cycle. At the equator, Uranus experiences 42 years of day and night and the opposite for its poles. It also has a dark side that heats up dramatically after about 40 years and is the source of violent storms. There is currently no known reason as to why Uranus experiences such extremes in weather.

The icy outer layer of Uranus is made of 80% fluid. Because the outer layer of Uranus lacks a solid surface, it’s enveloped in a thick, gaseous atmosphere. The atmosphere of Uranus is similar to that of Jupiter and Saturn, but contains more “ices” than the inner portions. Uranus’ atmosphere is composed mostly of molecular hydrogen, helium, and water, with traces of atomic helium and a small amount of methane.

Besides the surface temperature, Uranus also has many moons. There are 27 known satellites of Uranus. These are the smallest among the giant planets, but their total mass and atomic mass is relatively small. Five of these satellites stand out in particular: Titania, Ariel, Umbriel, and Alexander Pope. Despite its size, these satellites still show us many interesting facts about Uranus.


The eighth planet in our solar system, Neptune is the fourth gas giant planet. It is about 2.8 billion miles from the Sun. The planet’s rotation is nearly 19 hours long, and it takes 165 years to make one orbit around the sun. Neptune is made mostly of hydrogen and helium. The atmosphere is made up of hydrogen and helium, and the planet has 14 known moons.

Because of its far distance from the sun, Neptune’s atmosphere has few chances of warming up. As a result, Neptune’s atmosphere is extremely cold and its winds can reach up to 1,500 miles per hour (around 2,400 km/h). These winds are believed to be responsible for the largest dark storm ever recorded in the solar system, which was large enough to cover the Earth. It moved westward at a speed of 750 mph.

Today, it is unclear how exactly Neptune formed. Scientists think that the planet was born in a disk of material in the early solar system, but there wasn’t enough material to form it. Therefore, Neptune was formed at a distance 30 times greater than Earth was when it was formed. This distance probably happened to result in the formation of Neptune because it would have evaporated too much of the water on it. Studying Neptune’s formation may also help scientists understand what conditions were like in the early solar system.


Earth is the third planet from the Sun and the fifth largest in the solar system. It is one of only two places in the universe that is known to harbor life. The name Earth derives from the Old English and Germanic words for land and ground. Later, it came to mean planet itself. It is also the only planet to be named after no other god or goddess. It is a rocky terrestrial planet with active crust and oceans covering 70% of its surface.

The surface of the Earth is composed of many elements, chief among them oxygen and silicon. Other elements found in Earth’s atmosphere include magnesium, aluminum, nickel, and iron. The Earth’s outer layer is made of silicate and basaltic rocks and extends 18 miles (30 km) below the surface. The planet’s core is composed of a massive mountain range, called the mid-ocean ridge.

The formation of the solar system began from a spinning cloud of dust and gas. The dense center of the solar nebula became very hot and formed the sun. Other objects in the solar system continued to revolve around the sun. Some of them collided and stuck together, forming asteroids, planets, and moons. The Earth itself took billions of years to develop, and it has three layers.


A recent debate has erupted over whether Pluto is one of our planets or a dwarf planet. It was downgraded from a planet to a dwarf planet by the International Astronomical Union (IAU) in 2006. This decision was widely opposed, as it made science look arbitrary and undermined public trust in scientists. Regardless of whether it is correct or incorrect, it was a difficult decision for planetary scientists to make.

The 2006 resolution on the status of Pluto is a significant step forward. Pluto was classified as a planet before modern discoveries were made possible by the development of technology. Although the decision to declassify Pluto is an important step forward, there are many debates regarding whether it belongs in our solar system. For instance, a famous American President once ate an opossum, and his supporters made Teddy Bear-like figures of him.

While Pluto was considered a planet by the IAU when it was discovered in 1930, this was later changed when scientists discovered that it shared its orbit with other objects in the Kuiper Belt. Today, it is classified as a dwarf planet. In addition to Pluto, it sits alongside Eris, Ceres, Haumea, and Makemake. Unlike its bigger cousins, the planets in the Kuiper Belt are populated by comets, asteroids, and other space debris. The Kuiper Belt contains more than 3,000 objects that are more or less similar to Pluto than other planets in the Solar System.