The only planetary system that is known to man is our solar system. It is made up of nine planets. The nine major planets in our solar system are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. There are also many other minor planets, which are also in our solar system, but they are unimportant compared to the nine major planets.
Mercury, which is the planet that is closest to the sun, is the first and smallest of the inner planets. It is speculated that the heat from the sun made it impossible for the gases present to become part of the planetary formation. The surface of Mercury is extremely hot. It is approximately 470 degrees Celsius on the surface and is thought to be even hotter at the two hot spots. These hot spots are on opposite ends of the equator. It is the heat of the surface that makes it impossible for Mercury to have any type of atmosphere. Mercury orbits the sun once every 88 days and has a true rotation period of 58.6 days.
Venus is the second closest planet to the sun and is said to be the most closely resembles to Earth in size, density, and distance from the sun. Most scientists know Venus as the sister planet to the Earth. It is called this because it closely resembles the Earth’s mass, density and diameter. The only thing different is that Venus is shrouded in thick clouds that completely hide the surface of the planet. The surface temperature is also much warmer than that of Earth. Venus completes one revolution around the sun in 224.7 days. This makes the Venusian day equal to 117 earth days. It is thought that this slow rotation may be the reason why Venus has no magnetic field. The atmosphere of Venus is made up of 98% carbon dioxide and 2% Nitrogen. This atmosphere also has the presence of helium, neon and argon.
Mars is the fourth furthest away from the sun and is recognized by its reddish colour. Mars is also very much like the Earth. More than any other planet in the solar system, Mars has...
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