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Phenomena > Stars & Constellations

Stars & Constellations

Stars | Constellations


Stars are big balls of very hot gases such as hydrogen, helium, oxygen, and nitrogen. Stars can contain other elements too, such as iron and clacium. Stars shine by converting the hydrogen into helium, release a lot of energy in the form of heat and light, this works much like the hydrogen bomb, or the atom bomb.

The sun is the most important star to humans because it is so close to the Earth. The sun supplies Earth with the light and energy it needs to sustain human life.

Because the sun is so close to the Earth, it is hard for humans to observe it without special equipment; if humans look directly into the sun it will damage the eyes. Other stars are much further away and are easier for humans to look at.

The North Star (Polaris): The North Star marks the earth's north pole. Polaris appears about halfway up the sky to the north, the elevation above the horizon equal to the observer's latitude. The pole itself, about which Polaris goes, marks true north, the fundamental direction for inhabitants of the northern hemisphere that defines the others, east, west, and south. Polaris also marks the end of the handle of the Little Dipper, the prominent figure of Ursa Minor. Polaris has the common reputation of being the brightest star in the sky. The sun at noon marks the meridian, making it possible to identify due north or south.

Many navigators, particularly the Vikings, relied on the North Star while at sea.

Sirius: Sirius is the brightest star in the sky. Sirius is part of the constellation Canis Major, which looks like a dog in the sky. Sirius takes the form of the dog's nose in that constellation.That is why Sirius is commonly known as the Dog Star.

The Egyptians called Sirius "Sothis." The realized that Sirius's first helical rising occured just before the flooding of the Nile. A helical rising is when an object in the sky reappears after a period of absence; its first appearance occurs in the morning before the rising of the sun. Because of this, the Egyptians based their calendar on the rising of Sirius in the sky.

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Click here for solar cycle image
View the North Star and Sirius and the constellations they are part of. [enlarge]

Navigate using the stars, like the Wayfinders of Oceania and the Vikings. Keep time with the Stars like the Ancient Egyptians.

"If you stood still in one place all day long, you could tell what time it was by your shadow." Learn about how the solar cycle helps humans to keep time."

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