Have binoculars? Test your eyesight by looking at the second star again. Look closely, and you may see two stars, which have been called the Horse and Rider. According to the Greeks, the second star is one of the Pleiades sisters, who left her six sisters over in Taurus when she married. Interestingly, from spectroscopic evidence it is known that Mizar A and Mizar B are each double stars as well, although these pairs are not resolvable by existing telescopes.
Likewise, the constellation of Orion the Hunter [see image below] can be used as a sign post for the southerly viewed sky. While Orion is not a circumpolar constellation, it does however dominate the sky when looking toward the south in North America from winter through spring.
It can be used much like the Big Dipper stars are used to find other objects of interest in that part of the night sky. Image Source: Stellarium Move cursor over image to see asterism outline. Finding other constellations using the Big Dipper If you can find the big dipper in the sky, you have a starting point for identifying many other stars. Send emails to: webmaster fortworthastro. A companion star to Alcor was discovered in , when astronomers using adaptive optics on the inch Hale Telescope at the Palomar Observatory saw an unfamiliar source of light next to the star.
Adaptive optics corrects the focus to adjust for changes in the atmosphere, allowing for a clearer picture. Some Native American legends say the bowl of the Big Dipper is a bear and the stars of the handle are three warriors chasing it. In the United Kingdom and Ireland, it is called the Plough. That idea may have arisen from an old Nordic constellation that was believed to represent a wagon or chariot belonging to the chief god, Odin, said Tom Kerss, an astronomer at the Royal Observatory Greenwich.
In Danish, the constellation was called "Karlsvogna," which means "Charles' wagon" in English. Some 19th-century texts refer to the Plough by that name, he said. In other cultures, the asterism is a ladle China, Japan and Korea , a cleaver northern England , a cart Germany and Hungary , a saucepan the Netherlands , a salmon net Finland and a coffin Saudi Arabia.
The Big Dipper serves as a pointer to other locations in the sky. The rule is, spring up and fall down. The appearance of the Big Dipper changes from season to season. In autumn, it rests on the horizon in the evening. In winter evenings, the handle appears to be dangling from the bowl. In spring, it is upside down in the evening hours, and in summer the bowl leans toward the ground.
The asterism serves as a guide to a number of bright stars, too. Following the line further leads to Spica , also one of the brightest stars in the sky , located in the constellation Virgo. Two of the stars marking the cup of the Big Dipper lead the way to Polaris , the North Star, and another pair of stars, Megrez and Phecda, point the way to Regulus , the brightest star in Leo and also one of the brightest stars in the night sky, and also to Alphard , the brightest star in Hydra constellation.
The line from Megrez to Dubhe points the way to Capella in Auriga constellation , and one drawn from Megrez to Merak leads to Castor in Gemini when extended by about five times the distance between the two stars.
In about 50, years, the stars of the Big Dipper will be at different locations, which will result in the asterism changing shape and facing the opposite way.
Still, as most of the stars that form the asterism all except Alkaid and Dubhe are members of the Ursa Major Moving Group, which means that they share common motion through space, the asterism will not look significantly different. The pattern will be present even , years from now, but the shape of the handle, with Alkaid marking the tip, and the end of the bowl marked by Dubhe, will appear slightly different. The Big Dipper rotates around the north celestial pole, and always points the way to the North Star.
Since the Little Dipper is not quite as prominent in the sky as its larger neighbour, it is easier to use the stars of the Big Dipper to find both the North Star and true north. To find Polaris , follow the line from the Pointer Stars , Merak and Dubhe, to the first bright star along the same line. That is the North Star. Merak and Dubhe are the stars that mark the end of the bowl of the Big Dipper. They are called the Pointer Stars because they point the way to Polaris and true north.
The Big Dipper is associated with a number of different myths and folk tales in cultures across the world. In eastern Asia, it is known as the Northern Dipper. Of the stars nearest to our Sun, about half are known to be in multiple systems two or more stars.
These systems reveal a great deal of information. Because of their interactions, astronomers can determine the gravitational pull exerted by the companions and calculate the mass of the individual stars.
Polaris is helpful to astronomers in another way; it is a variable star. Polaris pulsates, a change we detect as a pattern of dimming and brightening. This pulsation helps astronomers calculate celestial distances. Why Doesn't Polaris Move?
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