January 23, 2014

Planets in Solar System

Nine Planets in Order

Author: nitin.p070


Sun is at the centre of our solar system. Our solar system is nearly five billion years old. It contains nine planets in order ( now it is eight), a handful of so called dwarf planets and more than 170 moons, and dust, gas and thousands of asteroids and comets all orbiting around the central Sun. Now let us discuss the Nine planets in Order.

MERCURY: Mercury is the closest planet to Sun. With pluto's demotion to dwarf planet, it becomes the smallest planet of Solar System. Mercury's elliptical orbit takes the small planet as close as 29 million miles (47 million kilometers) and as far as 43 million miles (70 million kilometers) from the sun. If one could stand on the scorching surface of Mercury when it is at its closest point to the sun, the sun would appear almost three times as large as it does when viewed from Earth. Temperatures on Mercury's surface can reach 800 degrees Fahrenheit (430 degrees Celsius). Because the planet has no atmosphere to retain that heat, nighttime temperatures on the surface can drop to -280 degrees Fahrenheit (-170 degrees Celsius).

VENUS : Venus and Earth are similar in size, mass, density, composition, and distance from the sun. There, however, is where the similarities end. Venus is covered by a thick, rapidly spinning atmosphere, creating a scorched world with temperatures hot enough to melt lead and a surface pressure 90 times that of Earth. Because of its proximity to Earth and the way its clouds reflect sunlight, Venus appears to be the brightest planet in the sky.

EARTH; Earth, our home planet, is the only planet in our solar system known to harbor life. All of the things we need to survive are provided under a thin layer of atmosphere that separates us from the uninhabitable void of space. Earth is made up of complex, interactive systems that are often unpredictable. Air, water, land, and life—including humans—combine forces to create a constantly changing world that we are striving to understand. Viewing Earth from the unique perspective of space provides the opportunity to see Earth as a whole. Scientists around the world have discovered many things about our planet by working together and sharing their findings.

Facts of Nine Planets:

Some facts are well known. For instance, Earth is the third planet from the sun and the fifth largest in the solar system. Earth's diameter is just a few hundred kilometers larger than that of Venus. The four seasons are a result of Earth's axis of rotation being tilted more than 23 degrees.

MARS: The Red Planet ,Mars is a small rocky body once thought to be very Earth like. Like the other terrestrial planets—Mercury, Venus, and Earth—its surface has been changed by volcanism, impacts from other bodies, movements of its crust, and atmospheric effects such as dust storms. It has polar ice caps that grow and recede with the change of seasons; areas of layered soils near the Martian poles suggest that the planet's climate has changed more than once, perhaps caused by a regular change in the planet's orbit.

JUPITER: The most massive planet in our solar system, with four planet-size moons and many smaller satellites, Jupiter forms a kind of miniature solar system. Jupiter resembles a star in composition. In fact, if it had been about eighty times more massive, it would have become a star rather than a planet. On January 7, 1610, using his primitive telescope, astronomer Galileo Galilei saw four small "stars" near Jupiter. He had discovered Jupiter's four largest moons, now called Io, Europa, Ganymede, and Callisto. Collectively, these four moons are known today as the Galilean satellites.

SATURN: Saturn was the most distant of the five planets known to the ancients. In 1610, Italian astronomer Galileo Galilei was the first to gaze at Saturn through a telescope. To his surprise, he saw a pair of objects on either side of the planet. He sketched them as separate spheres and wrote that Saturn appeared to be triple-bodied. In 1659, Dutch astronomer Christiaan Huygens, using a more powerful telescope than Galileo's, proposed that Saturn was surrounded by a thin, flat ring. In 1675, Italian-born astronomer Jean-Dominique Cassini discovered a "division" between what are now called the A and B rings. It is now known that the gravitational influence of Saturn's moon Mimas is responsible for the Cassini Division, which is 3,000 miles (4,800 kilometers) wide.

URANUS: Once considered one of the blander-looking planets, Uranus has been revealed as a dynamic world with some of the brightest clouds in the outer solar system and 11 rings. The first planet found with the aid of a telescope, Uranus was discovered in 1781 by astronomer William Herschel. The seventh planet from the sun is so distant that it takes 84 years to complete one orbit. It appears bluish green in dim sunlight.

NEPTUNE: The eighth planet from the sun, Neptune was the first planet located through mathematical predictions rather than through regular observations of the sky. (Galileo had recorded it as a fixed star during observations with his small telescope in 1612 and 1613). Nearly 2.8 billion miles (4.5 billion kilometers) from the sun, Neptune orbits the sun once every 165 years. It is invisible to the naked eye because of its extreme distance from Earth.

PLUTO: The world was introduced to dwarf planets in 2006, when petite Pluto was stripped of its planet status and reclassified as a dwarf planet. The International Astronomical Union (IAU) currently recognizes two other dwarf planets, Eris and Ceres.What differentiates a dwarf planet from a planet? For the most part, they are identical, but there's one key difference: A dwarf planet hasn't "cleared the neighborhood" around its orbit, which means it has not become gravitationally dominant and it shares its orbital space with other bodies of a similar size.

These nine planets in order are and the property of these nine planets are explained above. Out of these nine planets, our planet " The Earth" is the only planet where life is possible. Now scientists are conducting experiments to find out whether any possibility of life in any other planet other than our own planet " Earth".

Of these nine planets, Venus is the brightest planet and closest to our Earth. We can see this planet Venus in naked eye itself. Mercury and Pluto are forming the extreme points in our Nine planets in order.

Article Source: http://www.articlesbase.com/science-articles/nine-planets-in-order-6356087.html

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