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The Big Dipper (Reference to Locate Stars in the Night Sky)
How Often Do You Watch the Night Sky?
The Big Dipper as a Navigation Aid
The Big Dipper is an asterism composed of seven stars; Alkaid, Mizar, Megrez, Allioth, Phecda, Merak and Dubhe, which lies in the northern hemisphere night sky. This asterism is circumpolar, meaning that it is located close Polaris, the northern star. The Big Dipper and other asterims, such as Cassiopeia never set from sight to the north hemisphere observers and they are always visible during clear night skies.
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 they remain low on the horizon. Since this asterism is and has been mentioned by different cultures, it is normally mentioned in tales.. Explorers and travelers often use the Big dipper as a navigation tool to guide them.
How the Big Dipper was Imagined by Ancient Cultures
Germany____________ Great Wagon
Ireland and Birtain_______ Plough
India _______________Seven Great Sages
Indonesia ____________Canoe stars
China ____________A wall; seven Gods
American Indians ______ Bear
Navigation Aid (The Big Dipper)
The Big Dipper was utilizad in ancient times and in recent times, as well, as a navigation aid by sailors, explorers, conquerors. In recent times, this asterism results of great help for campers and open country goers. The Big Dipper can be easily observed with the naked eye, but a telescope will allow you to observe other objects, such as Messieur Objects (M51, M63, M106, M94) and other galaxies. and planetary nebulas.
For people living in the northen hemisphere, the Big Dipper may be located just above their head, depending on your location. For those living in the northern latitudes, it may remain visible throughout the entire year; however, for most people living above 40° latitude, this asterism will be observable.
Big Dipper and Polaris
The proximity of the Big Dipper to Polaris makes provides the perfect starting point from where start you exploration of the starry night sky. The first hing that one sees on a clear night in the direction of tthis asterims is a goup of seven stars that are aligned as if forming the figure of a shopping cart, with a long handle.
If you look around, this group of stars are aligned in a rectangular form, giving shape to straight lines if one were connecting them with lines. The imaginary connections could allow us to locate other stars and constellations in the sky. The easiest method to do these connections is to draw them on paper and then compare it to the starry night sky.
The Big Dipper is not a constellation, but, forms part of the constellation of Ursa Major, and it contains seven stars; Dubhe, Merak, Phecda and Megrez, which give shape to the bowl, and Alioth, Mizar and Alkaid forming the handle. All of these stars can be used to locate other objects in the sky.
A Schetch of the Big Dipper and Circumpolar Stars and Asterisms
How to Find Polaris?
Polaris, the northern star, can be found by extending an imaginary line from Merak to Dubhe, then, displacing this line five times the distance between these stars. Another imaginary line from Megrez to Phecda and about eight times that distance between these stars leads to Regulus, one of the brighesdt stars, in the constellation of Leo.
Another line from Megrez to Dubhe and continuing approximately seven times that distance leads to Capela in Auriga. Drawing a curved line from Mizar to Alkaid and extending it for about six times ahead leads to Arcturus in Bootes; continuing a bit further, in the same curved direction, one gets to Spica in Virgo. A diagonal line from Phecda to Dubhe and stretching it to about 8 times its distance leads to Cassiopeia, which can be easily recognizable for its five stars, that form the letter W.
The Big Dipper as a Starting Point
Technique for Locating Stars
Using this technique of drawing lines from star to star on paper and then comparing it to the night sky, results effective for navigating around the night sky. You may also use other objects, such as asterisms or single stars to locate other stars in the sky; for example, utilizing Orion as the point of departure, one can locate Taurus, The Pleiades, Canis Minor, Sirius; gemini and other celestial objects.
The Big Dipper Throughout Histtory
Throughout history, amy cultures have been able to observe the Big Dipper and for this reason, it is mentioned in various writings, In the Bible, the Big Dipper is mentioned as the seven stars in the pasage of Amos 5:8. In Hindu astronomy, it was known as Sapta Rishi, which means the seven great sages and each star is named after one of them
In Mongolia it was 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 seen as a giant bear, and the handle represented a group of warriors going after the bear. This asterism is portrayed on the Alaskan state flag, too.
Stars that Form the Big Dipper
Distance 101 Light years
Distance 78 light years
Distance 58 lighht years
Distance 84 light years
Distance 79 light years
Distance 124 light years
The Big Dipper Above 40° North Latitudes
The Big dipper never disappears from sight at latitudes of 40 degrees or more in the northern skies, given there is clear skies. A full moon will diminish visibility; however, you may be able to view the Big Dipper from behind a building, mountain or in between a group of trees.