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Solar System |
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Topics |
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Contents |
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Sun
Moon
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto
Comet
Meteor
Asteriods |
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What is Solar System ? |
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The Earth is not the only planet to orbit the Sun. Eight other spinning planets are also in orbit. The nearest is Mercury, which is only 58,000,000km from the Sun. It takes 88 days to complete one orbit. The furthest is normally Pluto, which is on average 5,900,000,000km from the Sun. Part of Pluto's orbit lies within that of Neptune. Pluto takes nearly 248years to orbit the Sun. All natural objects which orbit the Sun make up the pulling power of the Sun. Force such as this is called gravity. |
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Exploring the Solar System |
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Some astronomers think that there may be a tenth planet on the edge of the Solar System. This is because gravity from an unknown source, as well as from Pluto, is tugging at the orbit of Uranus and Neptune. Could this be planet X ? It is more likely that the source of gravity is a star outside the Solar System than another planet.
There are still many mysteries in the Solar System. Today, astronomers have a better chance than ever of solving them. They have fine observatories and radio telescopes on Earth, as well aw telescopes and rays detectors in space. They can land humans on other worlds to set up experiments. In future years astronauts will be sent to Mars.
Spacecraft without people on board, called probes, will examine asteroids and the planet Pluto. Probes have already crossed Solar System, studying comets and photographing planets. Pioneer 10 was the first to leave the Solar System and head for the stars.
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Home |
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