As it has been stated our solar system has nine planets. Mercury is the planet which is close to sun and also is the smallest one (excluding Pluto). Mercury rotates on its own axis is 58.65 days. However, to complete one revolution it requires 88 days. Mercury can be seen from earth as an evening star after sunset or morning star before dawn.

Venus is the one of the highest planet in the solar system. Venus is known as the evening stat in popular terms. Venus is mostly seen in eastern side in morning and in western direction during evening time. Since, mercury and Venus are closest to sun; they are the hottest planet in the solar system.

Mars is known as the red planet it is visible from earth. This planet has iron oxide which is red in colour. Therefore, the name is red planet. Mars also has two small satellites which are named as Phobos and Deimos.

Jupiter is the biggest and largest planet of solar system. The total mass of Jupiter is about 71% of total mars of the planets. The volume of Jupiter is one and half times of all other planets combined. It has a close atmosphere of earth like hydrogen, methane, ammonia, water etc. Jupiter has major 10 satellites which has names like: –

  1. Europe
  2. Ganymede
  3. Lo
  4. Callisto
  5. Adrastea

Another planet, Saturn is nine times larger than earth. This is second largest planet in solar system. It is a close ally to Jupiter. The density of Jupiter is some or less than that of water which is around 0.69. Saturn is said to have around 17 satellites. Out of these 17, the major ones are: –

  1. Titan
  2. Enceladus
  3. Mimas
  4. Lapetus
  5. Dione etc.

Saturn has spectacular system of rings which is around 100 feet nick. This is composed of various kinds of ripping and operating bands etc.

Earth, the only planet where life sustain is old about 45 thousand million years. The shape of the earth resembles a globe (almost spherical) which is compressed on the pole sides. The earth is bulky around the equator. An equator is an imaginary line that divides the earth is two equal spheres, namely northern and southern hemisphere. In technical terms the shape of the earth is called an oblate spheroid or an oblate ellipsoid. The equatorial diameter of earth is measured about 12,755 km. The polar diameter of our planet is around 12,714 km. Earth has two motions, one around the sun which is revolution and the other, on its axis, known as rotation. The revolution is however annual. The earth rotates on its axis once an around 24 hours whereas the revolution completes in 365.25 days. This revolution is the cause of season change in the world. If one determines the velocity of rotation on earth axis, he should consider the distance of the place from equator. The rotational velocity of the poles is zero. The greatest velocity of earth is found at the equator which is about 1700 km per hour. Since, earth revolves around in an elliptical orbit, therefore the distance between the earth and the sun keeps changing. The minimum distance measure is 14700,000 km. This minimum distance is on the day January 3 which determine the earth in perihelion mode and the maximum is around July 4 (15200,000 km). This phase is known as aphelion. Perihelion means ‘peri’ meaning surrounding or around and ‘helios’ meaning the sun. Aphelion means ‘apo’ meaning away or far off and ‘helios’ meaning the sun. Therefore, these represent closest and distant from the sun.