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Old Thursday, June 11, 2009
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Default Members of Solar System

Solar System
The solar system is made up of the sun, its planets, satellites, asteroids, meteoroids, and comets. Each of these bodies are held to each other by the force of gravity.

Members of Solar System

Members of the solar System includes the Sun and everything that orbits it like planets, their satellites, asteroids, comets, interplanetary gas and dust. The sun is by far the most largest part of the solar system, the other principal members of the solar system are the major planets.

A star that is the basis of the solar system and that sustains life on Earth, being the source of heat and light.

The sun is a medium sized star which is the center of the solar system. Its gravitational pull holds the planets, comets, etc. orbiting about it. It is the closest star to the earth at about 93,000.000 miles away. It is about 865,000 miles in diameter. Without the heat and light of the sun, there would not be life on earth. Solar energy is used by green plants for photosynthesis. The sun appears larger than the other stars because it is the nearest star to the earth. The sun is about 870,000 miles or 1,400,000 kilometers in diameter, and its volume is about 1,300,000 times that of the earth. Its mass is almost 700 times the total mass of all the bodies in the solar system and 332,000 times that of the earth. The sun's gravity is almost 28 times that of the earth.
The sun's surface is called the photosphere where its temperature is about 6,000 degrees Celsius. However, the temperature at its surface is about 6,000 degree Celsius however at core it is 15,600,000 degree celsius.

The planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The planets orbiting nearer the sun than the earth are called inferior planets; those whose orbits are larger are called superior planets.
The planets move almost in circular elliptical orbits based on the force of gravity. The sun's gravitational pull is the most powerful gravitational force in the solar system. The other heavenly bodies have a much smaller gravitational force on one another called perturbations.
The planets orbit the sun in the same counterclockwise direction. A planet's year is the time required for it to complete one full orbit around the sun. This is referred to as the planet's revolution. All the planets rotate about their own axes as they revolve around the sun,
The planets are grouped according to their physical properties.
Terrestrial Planets:
The inner planets Mercury, Venus, Earth, and Mars are called the terrestrial which means earthlike planets. They are dense and small in size. They have solid, rocky crusts and interiors of metal. Except for Mercury, they have gaseous atmospheres from which lighter elements have escaped because of the low gravitational force.
Jovian Planets:
The Jovian planets which include Jupiter, Saturn, Uranus, and Neptune all have great volume and mass but relatively low density i.e. thickness. Most of the nine major planets have one or more moons.

Mercury is the nearest planet to the sun. It is around 36 million miles (58 million km) from the sun and takes 88 days for Mercury to orbit the Sun.
It has a diameter of about 3,000 miles or 4,800 kilometers. Its density or thickness of the materials that make it up is similar to that of the earth. It is very small so it has less of a gravitational pull on other space objects. Small amounts of carbon dioxide have been detected on its atmosphere. Its rotation on its axis is equal to 59 earth days. This results in periods of daylight and night of 90 earth days.
Temperatures during the day get as high as 800 degrees Fahrenheit or 450 degrees Celsius. Night temperatures are thought to get as low as -300 degrees Fahrenheit or -180 degrees Celsius.

Venus is the second planet from the sun. It is about .67 million miles or 107 million kilometers from the sun. Venus' year equals about 225 days and is the amount of time it takes Venus to orbit around the sun. It comes closer to the earth than any other plane.
It is covered with a thick layer of clouds and has a surface temperature of 890 degrees Fahrenheit or 476 Celsius. The cloud layer holds in the heat and keeps the planet much hotter than the earth. The thick atmosphere made up mainly of carbon dioxide, with a slight amount of water vapor and a bit of nitrogen and other elements. Venus rotates on its axis 243 earth days . The temperature is very similar on the lit (daytime) and unlit (nighttime) parts of the planet.

Earth is the third planet from the sun and the fifth largest planet of the solar system and the only planet definitely known to support life. The distance from the earth to the sun is around 93 million miles. The force of gravity has molded the earth into a sphere. It is slightly flattened at the poles and bulges at the equator. The earth's diameter is around 7,926 miles or 12,760 kilometers and the polar diameter 7,900 miles or 12,720 kilometers. The circumference at the equator is around 25,000 miles or 40,000 kilometers. The surface of the earth is divided into dry land and oceans, the dry land takes up around 57.5 million square miles or 148.9 million square kilometers, and the oceans around 139.5 million square miles or 361.3 million square kilometers. The earth is surrounded by a band of gases called the atmosphere which is mostly nitrogen and oxygen.
It rotates or turns from west to east about a line called its axis. The period of one complete rotation is a day. Because of the rotation of the earth we experience day and night. It revolves about the sun once every 365 1/4 days which is a year. The path of this revolution, the earth's orbit, is an oval in shape. This means the earth is closer to the sun in January than it is in July.
The change in seasons is caused by the tilt of the earth on its axis. When the northern end of the earth's axis is toward the sun, the most direct rays of sunlight fall in the Northern Hemisphere. This causes its summer season. At the same time the Southern Hemisphere has winter since it is then receiving indirect rays. Halfway between, in spring and in autumn, there is a time called the equinox when all parts of the earth have equal day and night. When the northern end of the earth's axis is tilted away from the sun, the least direct sunlight falls on the Northern Hemisphere which causes winter.

Mars is the fourth planet from the sun, with an orbit next in order beyond that of the earth.
Mars is red in appearance due to oxides in its crust and is easiest to see opposite the sun. Furthermore it has a diameter of 4,200 miles or 6,800 kilometers, just over half the diameter of the earth, and its mass is only 11% of the earth's mass.
Mars has a very thin atmosphere made up of carbon dioxide, with some nitrogen and argon and it has an extreme day-to-night temperature range, resulting from its thin atmosphere, from about 80 degrees Fahrenheit 27 degrees Celsius at noon to about -100 degrees Fahrenheit or -73 degrees Celsius at midnight the high daytime temperatures are only present at less than 3 feet or 1 meter above the surface.
This planet has hot spots under the crust. This may explain volcano activity thought to be on Mars. There is evidence that Mars may have been warmer several billion years ago and that there may have been lakes, rivers, etc. that would have worn away the surface of Mars. It also has seasons like the earth. This shows up in the areas of the poles where there are thin polar caps that get smaller during Mars' summers and whiter and bigger during It's winters.
Mars is about 141 million miles 228 million kilometers from the sun. It orbits the sun in 687 days, which makes its year twice as long as ours or two of our years. A Mars day or time of rotation on its axis is just about the same as an earth day in length - about 24 hours.
Mars has two moons discovered. The innermost, Phobos, and the outer moon, Deimos.

Jupiter is the fifth planet from the sun and largest planet of the solar system.
Its orbit is about 484 million miles or 778 million kilometers from the sun. It orbits the sun every 12 years. In order from the sun it is the first of the Jovian planets so they have a thick atmosphere.
Jupiter has a diameter of 88,800 miles or 143,000 kilometers, Its mass is 318 times that of the earth and about 2 1/2 times the mass of all other planets combined.
The atmosphere of Jupiter is made up mostly of hydrogen, helium, methane, and ammonia. The atmosphere seems to have a number of light and dark bands parallel to its equator.
Jupiter has no solid rock surface. One theory is that there is a gradual transition from the outer ammonia clouds to a thick layer of frozen gases and finally to a liquid or solid hydrogen mantle. Beneath that Jupiter probably has a core of rocky material with a mass 10 - 15 times that of the earth.
Jupiter's day is about 10 hours. This rotation causes a polar flattening. The temperature ranges from about -190 degrees Fahrenheit or -128 degrees Celsius for the visible surface of the atmosphere, to 9F (-13C) at lower cloud levels. Certain regions reach as high as 40F (4C) at still lower cloud levels near the equator. Jupiter gives off four times as much heat as it gets from the sun. This heat emission may contribute to a slow contraction of this planet.
There are sixteen moons that orbit Jupiter. Europa, Ganymede, and Callisto.A second group is made up of the four innermost moons of Metis, Adrastea, Amalthea, and Thebe. The final group consists of the eight moons with orbits outside that of Callisto: Leda , Himalia , Lysithea , Elara , Ananke , Carme , Pasiphae, and Sinope . in addition Jupiter has three rings.

Saturn is the sixth planet from the sun. Its distance from the sun is around 886 million miles or 1.43 billion kilometers , almost twice that of Jupiter. It takes Saturn about 29 1/2 years to orbit or revolve around the sun.
Saturn is covered with a thick atmosphere made up of hydrogen and helium.. Saturn's temperature is believed to be about -270 degrees Fahrenheit or -168 degrees Celsius.
Saturn's day is about 10 and one half hours. This rapid rotation makes the largest polar flattening among the planets.
Saturn is the second largest planet in the solar system. Saturn's diameter is around 75,000 miles 120,000 kilometers. Its volume is more than 700 times the volume of the earth and mass is about 95 times that of the earth although less dense, making it lighter than water. It has five rings and eighteen known moons. Pan, Atlas, Prometheus, Pandora, Epimetheus, Janus, Mimas, Enceladus, Tethys, Telesto, Calypso, Dione, Helene, Rhea, Titan, Hyperion, Iapetus, and Phoebe. More than a dozen others have been thought to exist.

Uranus is the seventh planet from the sun. It is around 1.78 billion miles or 2.87 billion kilometers and orbits the sun every 84 years.
Uranus has a diameter of around 32,000 miles or 47,000 kilometers, four times that of the earth, and a mass or weight is about 15 times that of the earth. In addition it has a thick atmosphere of hydrogen, helium, and methane. Uranus' day is around 18 hours.
Its temperature is about -330 degrees Fahrenheit or -200 degrees Celsius,
Uranus has twenty moons and 11 rings.

It is the eighth and currently the last planet of solar system. It is about about 3 billion miles or 4.5 billion kilometers from the sun. It orbits the sun about 165 years. During short periods, the orbit of Pluto tilts in such a way that Neptune is sometimes further from the sun than Pluto which formerly was considered as a planet.
Neptune has a diameter of about 30,700 miles or 49,000 kilometers, nearly four times that of the earth. Its mass is about 17 times the earth's mass. It is much like Uranus as it has a thick atmosphere of hydrogen, helium, methane, and ammonia and a rapid period of rotation.
Neptune's atmosphere has zones like Jupiter's and giant storm systems that look like dark spots on its surface. Its temperature is similar as well i.e. -350 degrees Fahrenheit or -212 degrees Celsius. Furthermore Neptune has eight moons and a ring system made up of three bands.

A comet is a natural heavenly body made up of dust and gases that moves in an orbit around the sun. Comets can be spotted for varying amounts of time from the earth.

A comet far from the sun is made up of a thick solid body bodies called the nucleus. As it approaches the sun the nucleus becomes wrapped by a bright reflection of dust and gases called the coma. As it approaches the sun a tail which can flare out away from the sun as much as 100 million miles or 160 million kilometers In length appears.
Near the sun a comet can change a great deal in size and shape. The comas of comets vary widely in size, some being as large as planets. However, the nucleus, which makes up virtually all a Calmat's mass or weight, is much smaller. Comets lose particles and brightness with each time it passes near the sun. Some of these pieces move around the Calmat's orbit as a stream of meteoroids. When the earth passes through this path, a meteor shower is seen.
There are also very small comets only up to 40 feet or 12 meters wide. It is thought that as many as 43,000 reach the earth each day and break up at altitudes of 60015,000 miles or 95024,000 kilometers.

Last edited by Last Island; Thursday, June 11, 2009 at 06:50 PM.
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Old Thursday, June 11, 2009
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A goOd effort,but there r total 8 members of solar system,according to new realities of modern research.Dear, pluto is no more member.ASPIRANT SHOULD ALWAYS ABREAST HIMSELF OF NEW DEVELOPMENTS.HOWEVER GOOD EFFORT.
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Old Thursday, June 11, 2009
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