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SkyTour - The Planets

Cygnus Lyra

The word "planet" means "wanderer" because the planets, unlike most of the other "stars" whose positions remain fixed, wander from night to night. A fixed star that is part of a constellation will remain night after night, year after year at the same spot in the constellation. But the planets gradually, night after night change their position. This apparent change of position is because both the planet and the Earth are orbiting around the Sun and their relative position is constantly changing so the planet gradually appears to move around the sky. But even planets do not wander freely about. Since all the planets, including the Earth, are in a common plane around the Sun, the planets are always near an imaginary line drawn through the sky called the ecliptic. The constellations found along the ecliptic are the constellation of the Zodiac.

The Planets

Mercury is the closest planet to the Sun which makes it very difficult to see since it's rarely above the horizon during the night.

Venus is the third brightest object in the sky after the Sun and the Moon. It's also quite close to the Sun, so can only been seen around sunrise and sunset. Although Venus never rises very high in the sky, at times it can be seen late enough after sunset or early enough before sunrise to be in total darkness and is then very easy to spot. Venus is also called the morning or evening star.

Earth is a beautiful water rich planet and the only place in the Universe that we are absolutely sure contains beings that can look up and gaze at the sky.

Mars, depending on where it's in its orbit can vary greatly in brightness. Its color is distinctively red.

Jupiter is the largest planet and can easily be seen with the naked eye. With a telescope, or possibly even binoculars, you can observe 4 of its largest Moon change patterns as they orbit the giant planet.

Saturn is both smaller than Jupiter and much farther away so it is not nearly as bright, but still is easily visible to the naked eye. Of course Saturn is known for its rings which are among the most extraordinary and beautiful objects in our Solar System. You'll need a small telescope to see them well.

Uranus is just visible to the naked eye under ideal conditions, if you know exactly where to look.

Neptune is only visible through a telescope.

Pluto is a dwarf planet and only visible through a fairly large telescope.

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