Harshvardhan Exploring Space

       The sun is the star at the center of the solar system. It is nearly a perfect sphere of hot plasma, heated to incandescence by nuclear reaction in its core, radiating the energy mainly as visible light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.34 million kilometers or 109 times as that of the Earth. Its mass is about 330000 times that of the Earth and accounts for about 99.86% of the total mass of the Solar System. Roughly three quarters of the sun mass consists of Hydrogen, the rest is mostly Helium with much smaller quantities of heavier elements, including Oxygen, Carbon, Neon and Iron.

  Neptune is the eighth planet from the Sun Mass of Neptune is 1.024x10 26 kg . Neptune is 4.4765 billion kms away from the Sun. It completes one revolution in 165 years and one rotation is 16 hours . It is one of the gaseous giants of our solar system. Neptune is inferior to Uranus and exterior to Saturn. Voyager 2 was the spacecraft that marked the beginning of Neptune exploration in 1989. Neptune is named after the Roman god of sea, Poseidon .

Saturn is the sixth planet in our Solar System Saturn completes one revolution in 29.457 Earth years . Mass of Saturn is 5.683 x 10 26 Kg . It is 1.4946 billion kms away from the Sun. It has visible rings and therefore sometimes referred to as the most beautiful planet. So far it has 82 known moons . It is a gaseous giant that contains crystals of Ammonia in upper atmosphere and hydrogen and helium. It is the least dense planet in the Solar System, that means if we can find a reservoir of water large enough, Saturn could float in it. It has second fastest winds , with Uranus leading the chart. It is the second largest planet after Jupiter.

Jupiter is the fifth planet from the Sun. Jupiter is the largest planet of our Solar System. It is also called a gas giant . Jupiter completes one revolution in 11.86 years. Mass of Jupiter is 1.898x10 27 Kg . Jupiter is 778.5 million kms away from the Sun. Jupiter has 79 moons . Jupiter completes one rotation in 0.41 Earth days. It is inferior to Saturn, Uranus and Neptune while exterior to the others. Jupiter is named after the principal Roman God, Zeus . 

Pluto is considered as a dwarf planet since 2006. Mass of Pluto is 1.30900 x 10 22 Kg. Distance of Pluto from the Sun is 39.5 astronomical units . Pluto completes one revolution in 248 years . It was discovered by Clyde Tombaug in 1930 . Pluto is extremely cold as it receives very less sunlight. International Astronomical Union decided on the below criterion to call an astronomical object a planet: Its gravity should be enough to give it a round shape It should orbit around the sun Its path should be clear Pluto fails to get full marks in the above as its orbit is not clear, there are five known objects that are sometimes categorised as its satellites and sometimes as individual dwarf planets.

Venus is the second brightest object in the night sky. It is 67 million miles away from the Sun. Sometimes it is called the morning or the evening star. Romans named Venus after their goddess of love and beauty . Venus is sometimes called Earth's sister as it is comparable in size and gravity. It is also the hottest planet in our Solar System. Venus rotates much more slowly than Earth does, so a day on Venus lasts for 243 Earth days . Venus rotates in the opposite direction as compared to Earth. Venus is inferior to Earth and exterior to Mercury . Venus revolves around the Sun in 224 Earth days.