Our Solar System


Our solar system consists of the Sun, eight planets, the Asteroid belt, and the Kuiper belt. Originally, we had nine planets. But Pluto didn’t meet the proper requirements that a planet must have to be classified as a planet. So it’s no longer considered to be an actual planet. Planets as small as Pluto, are now known as Dwarf planets. As of now, there are 5 Dwarf planets. The four inner planets are called terrestrial planets and the four outer planets are called gas giants.

The Sun

The Sun is by far the largest object in our Solar System. It holds 99.8 % of the entire mass of our Solar System. The Sun is an ordinary Star, just like billions of other ones in the Universe. The Sun is classified as a normal main-sequence G2 Star. The Sun is composed of 70 % Hydrogen and 28 % Helium. Everything else (metals) amounts to less than 2 %. The Sun has been shining for about 4.6 Billion years, and it will continue to do so for about another 5 Billion year. Or until it runs out of Hydrogen to burn. The Sun has eight planets and many smaller objects orbiting it.

Key Details:

* Diameter: 1, 390, 000 KM

* Mass: 1.989e30 KG

* Temperature: 5800 K (Surface) 15, 600, 000 K (Core)


Mercury is the closest planet to the Sun. It’s also the eighth largest. Due to Mercury’s short distance from the Sun, temperatures get fairly high on Mercury. Mercury has an extremely thin atmosphere. It has a lot of atoms flying off it’s surface by the Solar Wind. Mercury has no Moons.

Mercury has been visited by two space-crafts. NASA, recently in 2004, launched a new space-craft to Mercury. It will send back much higher quality images, than the old space-crafts did. Mercury has a very weak magnetic field. It’s strength is about 1 % of Earth’s. It takes Mercury only 88 days to make a complete orbit around the Sun.

Key Details:

* Orbit: 57, 910, 000 KM (0.38 AU) from the Sun

* Diameter: 4, 880 KM

* Mass: 3.30e23 KG


Venus is the second planet from the Sun, and the sixth largest. Venus is the most brightest object in the sky. (Not including The Sun or the Moon). Venus is also called Earth’s sister planet, at times, due to the two planets close similarities. Venus does not have any Moons.

There are very strong winds raging on the cloud tops of Venus. It’s believed, that at one time Venus had liquid water on it’s surface. But all the water has now boiled away. Venus is very dry now. Venus also has several active volcanoes on it’s surface. It takes Venus 225 Earth days to complete an orbit around the Sun.

Key Details:

* Orbit: 108, 200, 000 KM (0.72 AU) from the Sun

* Diameter: 12, 103, 6 KM

* Mass: 4.869.24 KG


Earth is the third planet from the Sun. It’s also the fifth largest. Earth has been divided into several layers, which have distinct chemical and seismic properties (depth in kilometers). Earth only has one Moon, but NASA has placed their own artificial satellites to orbit Earth. One of the most interesting things about Earth is that it’s the only known Planet in which water can exist in liquid form. 71 % of Earth’s surface is covered with water. Thanks to Earth’s rich atmosphere, Earth is full of life. You can almost find life anywhere.

Earth is the only planet, whose name does not derive from Greek/Roman mythology. In the “ancient times” Earth was considered to be the center of the Universe. All these beliefs were brought to rest in the late sixteenth century by Copernicus. It was then proved, that Earth is a regular planet, orbiting a star. Just like billions of other ones in the Universe.

Key Details:

* Orbit: 227, 940, 000 KM (1.52 AU) from the Sun

* Diameter: 6, 794 KM

* Mass: 3.4219e23 KG


Mars, also known as the “red planet”. Is the forth planet from the Sun. It’s also the seventh largest. Early in Mars history, it was very similar to Earth. The very first space-craft to visit Mars was Mariner 4. It sent back detailed pictures to NASA. The pictures confirmed that Mars doesn’t have any life on it. However, evidence was found that millions of years ago, Mars could’ve supported life. Before the pictures were received, many people (even scientists) believed that Mars might have living creatures on it. But all those beliefs were brought to rest. Evidence from the pictures that NASA received from their space-crafts, also shows that Mars could’ve had liquid water on it’s surface in the past.

If Humans are to ever in-habit another planet, then the biggest candidate is Mars. Not only have we found evidence of previous life their, but Mars isn’t very far from us either. U.S.A is planning a man mission to Mars sometime in 2040. The entire trip to Mars, and back would take us about 2 and a half years. (Traveling at today’s modern speed). This is without mentioning the risks and dangerous factors of the trip. Mars has two moons.

Key Details:

* Orbit: 227, 640, 000 KM (1.52 AU) from the Sun

* Diameter: 6, 794 KM

* Mass: 6.4219e23 KG


Jupiter is the fifth planet from the Sun. It’s by far the largest planet in our Solar System. Jupiter is more than twice as massive as all the other planets in our Solar System combined.

The “great red spot” is a massive storm that’s been raging on Jupiter for more than 300 years, now. The storm is so huge, it can hold up to two Earth’s in it. Some scientists are starting to think that the great red spot might become a permanent feature of Jupiter. Jupiter is 1300 times more larger than Earth. Jupiter is also the fourth brightest object in the sky. Jupiter has a mind rattling 63 Moons. There could still be more.

Due to Jupiter’s strong gravitational pull (massive size) it has a strong influence on each of the planets, orbits around the Sun. Jupiter has been visited by several space-crafts. The space-craft “Galileo” orbited Jupiter for eight consecutive years. Sending back important pictures, and information regarding Jupiter, back to NASA.

Key Details:

* Orbit: 778, 330, 000 KM (5.20 AU) from the Sun

* Diameter: 142, 984 KM (Equatorial)

* Mass: 1.900e27


Saturn is the sixth planet from the sun, and it’s the second largest. Saturn is the least dense of all the planets in our Solar System. Saturn has been visited by many space-crafts. The most fascinating feature of Saturn, is it’s rings. There are four main groups of rings and three fainter, narrower groups of rings. Saturn’s rings are very thin. The origin of Saturn’s rings is completely unknown.

Saturn radiates more energy into space, than it receives from the Sun. Saturn has 34 known Moons. Scientists believe there could be more. But they can only speculate. Saturn and Jupiter are composed of similar chemicals. Which is why the two, are so alike.

Key Details:

* Orbit: 1, 429, 400, 000 KM (9.54 AU) from the Sun

* Diameter: 120, 536 KM (Equatorial)

* Mass: 5.68e26 KG


Uranus is the seventh planet from the Sun, and it’s the third largest. Uranus has only been visited by one space-craft. But that one space-craft, answered many questions related to Uranus, and a lot more. The space-craft confirmed that Uranus does have 21 Moons. Uranus is some times pronounced the wrong way. The wrong way to pronounce it is “your anus”, the proper way to pronounce it is “yoor a nus”.

Uranus is the first planet to be discovered in modern times. Uranus has very dark rings. Which makes it fairly difficult to see them. Uranus is sometimes barely visible on a very clear night. It can be easily spotted with binoculars, though. Unlike Saturn and Jupiter, Uranus is mostly composed of rocks and various ices.
Key Details:

* Orbit: 2, 870, 990, 000 KM (192.218 AU) from the Sun

* Diameter: 51, 118 KM (Equatorial)

* Mass: 8.683e25 KG

Asteroid Belt

The Asteroid belt is the region of the Solar System located between the orbits of Jupiter and Mars. Many irregular shaped bodies, known as asteroids, or minor planets. Reside within the Asteroid belt. The very first object of the Asteroid belt was discovered in 1801. Now known as Ceres.

Kuiper Belt

The Kuiper belt is a disk-like shaped region beyond the orbit of Neptune. It’s roughly 30-50 AU from the Sun. It’s very similar to the Asteroid belt. Being home to many small icy bodies, minor planets, and dwarf planets. The former planet, Pluto lies within the Kuiper belt.