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Uranus


Uranus is one of the smaller gas giants in our solar system, but it is still large enough to hold 64 planets the size of Earth.

For thousands of years mankind believed that there were only five planets in the solar system. But the astronomer William Herschel discovered Uranus in 1781. Uranus orbits the Sun more than twice as far as Saturn at a distance of about 287 crore kms. Uranus takes 84 Earth years to complete a single revolution around the Sun. Uranus has a distinct blue-green appearance, probably because of the concentration of methane in its upper atmosphere. It has a diameter of roughly 51,800 kilometers.

Uranus has a core composed of silicate rock and metals. The most abundant elements in Uranus' atmosphere are hydrogen and helium. Its atmosphere also contains methane and other hydrocarbons Like the other gas planets, Uranus has bands of clouds that blow around rapidly. But they are extremely faint Uranus has been visited by only one spacecraft, Voyager 2 on Jan 24 1986. Most of the planets spin on an axis nearly perpendicular to the plane of the ecliptic. But Uranus' rotational axis is almost parallel to the plane of its orbit. So it rotates on its side. Because of this, its poles are sometimes pointed almost directly at the Sun. This gives it unusually long seasons. As the planet follows its 84 year orbit around the Sun, each pole has 42 years of continuous sunlight followed by 42 years of darkness.

Uranus has eleven known rings which contain dark, boulder-sized particles.

Uranus has 21 named moons. Unlike the other bodies in the solar system which have names from classical mythology, Uranus' moons take their names from the writings of Shakespeare and Pope. Some of these moons are less than 100 kilometers wide and black as coal