The Big Dipper is one of the brightest and most recognizable asterisms (group of stars)
in the sky. This group of seven stars is located within the constellation Ursa Major in the night sky. and can be easily obserbed throughout the year, except fall, when it
lies low on the horizon. The group of stars in the Big Dipper forms part
of the circumpolar stars, named so because they remain near Polaris throughout the
year, therefore, they´re visible most of the times. Because the Big
Dipper is easily seen in the northern sky, it has been mentioned in the
tales of ancient cultures. Explorers and travelers often use the Big
dipper as a navigation aid.
The Big Dipper was used in ancient times as a navigation aid by sailors and other travelers. It was probably due to its brightness and to the fact that it is circumpolar to Polaris, the North Star. Depending on your location, circumpolar stars might be directly overhead for those living in the northern latitudes, and will remain visible throughout the entire year. The proximity of the Big Dipper to Polaris provides a major starting point from where to locate other stars in the sky. Indeed, Polaris is one of the major points from where to start searching stars, asterisms or constellations in the sky.
The Big Dipper, which is not a constellation by itself, forms part of the constellation of Ursa Major, and is composed of seven stars, with Dubhe, Merak, Phecda and Megrez, forming the bowl, and Alioth, Mizar and Alkaid forming the handle. While five of the stars of this asterism remain fixed within its group, the two stars at both ends, Dubhe and Alkaid are moving towards each other, and in 50,000 years from now, they will constitute the bowl of the new Big Dipper, while Phecda and Merak will become the handle.
For people living in the northern hemisphere, the Big Dipper is easily recognisible if just gazing at night sky on a clear night. The seven stars on the Big Dipper can be used to guide you into finding other stars and constellations. Polaris can be found extending an imaginary line from Merak to Dubhe, then extending these two stars distance five times straght ahead.
An imaginary line from Megrez to Phecda and about eight times that distance ahead leads to Regulus in the constellation of Leo. Another line from Megrez to Dubhe and continuing approximately seven times that distance leads to Capela in Auriga. Following the curve formed by Mizar and Alkaid leads to Arcturus in Bootes and continuing a bit further, in the same curved direction, one finds Spica in Virgo. A diagonal line from Phecda to Dubhe and stretching it to about 8 times its distance leads to Cassiopeia, easily recognisible for its five stars, forming the letter w.
Using this technique of drawing imaginary lines from star to star, it´s easy to navigate around the night sky. You may also use other asterisms or single stars to locate objects in the sky; for example, using Orion, one can locate Taurus, The Pleiades, Canis Minor, Sirius; gemini and other stars.
The Big Dipper has been known since ancient times. In the Bible, the Big Dipper is mentioned as the seven stars in Amos 5:8. In Hindu astronomy, it was known as Sapta Rishi, which means the seven great sages. In Mongolia it is known as the seven gods. In the British Isles, it is known as the Plough, although in Ireland, it is most referred as the Starry Plough. In Native American mythology, the bowl was considered as a giant bear, and the handle was a group of warriors chasing the bear.
The Big dipper never disappears from sight at latitudes of 40 degrees or more in the northern skies, and this asterism is portrayed on the Alaskan state flag, as well.
The Big Dipper was used in ancient times as a navigation aid by sailors and other travelers. It was probably due to its brightness and to the fact that it is circumpolar to Polaris, the North Star. Depending on your location, circumpolar stars might be directly overhead for those living in the northern latitudes, and will remain visible throughout the entire year. The proximity of the Big Dipper to Polaris provides a major starting point from where to locate other stars in the sky. Indeed, Polaris is one of the major points from where to start searching stars, asterisms or constellations in the sky.
The Big Dipper, which is not a constellation by itself, forms part of the constellation of Ursa Major, and is composed of seven stars, with Dubhe, Merak, Phecda and Megrez, forming the bowl, and Alioth, Mizar and Alkaid forming the handle. While five of the stars of this asterism remain fixed within its group, the two stars at both ends, Dubhe and Alkaid are moving towards each other, and in 50,000 years from now, they will constitute the bowl of the new Big Dipper, while Phecda and Merak will become the handle.
For people living in the northern hemisphere, the Big Dipper is easily recognisible if just gazing at night sky on a clear night. The seven stars on the Big Dipper can be used to guide you into finding other stars and constellations. Polaris can be found extending an imaginary line from Merak to Dubhe, then extending these two stars distance five times straght ahead.
An imaginary line from Megrez to Phecda and about eight times that distance ahead leads to Regulus in the constellation of Leo. Another line from Megrez to Dubhe and continuing approximately seven times that distance leads to Capela in Auriga. Following the curve formed by Mizar and Alkaid leads to Arcturus in Bootes and continuing a bit further, in the same curved direction, one finds Spica in Virgo. A diagonal line from Phecda to Dubhe and stretching it to about 8 times its distance leads to Cassiopeia, easily recognisible for its five stars, forming the letter w.
Using this technique of drawing imaginary lines from star to star, it´s easy to navigate around the night sky. You may also use other asterisms or single stars to locate objects in the sky; for example, using Orion, one can locate Taurus, The Pleiades, Canis Minor, Sirius; gemini and other stars.
The Big Dipper has been known since ancient times. In the Bible, the Big Dipper is mentioned as the seven stars in Amos 5:8. In Hindu astronomy, it was known as Sapta Rishi, which means the seven great sages. In Mongolia it is known as the seven gods. In the British Isles, it is known as the Plough, although in Ireland, it is most referred as the Starry Plough. In Native American mythology, the bowl was considered as a giant bear, and the handle was a group of warriors chasing the bear.
The Big dipper never disappears from sight at latitudes of 40 degrees or more in the northern skies, and this asterism is portrayed on the Alaskan state flag, as well.
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