The
Twenty-Seventh star in the Nautical Almanac is Dubhe, "The Back (of the
Great Bear)". It was formerly known as Ak, "The Eye." It forms the top
forward end of "the ladle" of the Big Dipper, the more famous asterism
that forms a "saddle" atop Ursa Major, The Great Bear (the rather
complicated relationship between The Big Dipper and The Great Bear can
be seen in the second picture).
Scientifically, Dubhe is known as Alpha Ursa Majoris, though it is not the brightest star in The Great Bear. It is a First Magnitude star, though the dimmest of the class.
The Big Dipper itself is often called Ursa Major. It is also known as The Plough, and sometimes The Sickle. The constellation plays an important role in the mythologies of most peoples as part of a hunting legend or a berserker legend. Dubhe itself is associated with the Egyptian cat goddess Bast, and is a Behenian star which astrologically gives safety to sojourners. Dubhe is the official star of the State of Utah. Along with Merak, which lies below it in the sky, Dubhe is one of the Guardian Stars or Guide Stars that point directly at Polaris.
Dubhe is a binary star (or possibly a trinary or quarternary). It lies 125 light years from Earth. It has 4.25 times the mass of the Sun. It has 30 times the radius of the Sun. It is a red-orange giant that is beginning to burn the iron at its core at a relatively cool 7600 degrees F. but it is 300 times as bright as the Sun. It's age is not known, but it is far along in its stellar life.
Scientifically, Dubhe is known as Alpha Ursa Majoris, though it is not the brightest star in The Great Bear. It is a First Magnitude star, though the dimmest of the class.
The Big Dipper itself is often called Ursa Major. It is also known as The Plough, and sometimes The Sickle. The constellation plays an important role in the mythologies of most peoples as part of a hunting legend or a berserker legend. Dubhe itself is associated with the Egyptian cat goddess Bast, and is a Behenian star which astrologically gives safety to sojourners. Dubhe is the official star of the State of Utah. Along with Merak, which lies below it in the sky, Dubhe is one of the Guardian Stars or Guide Stars that point directly at Polaris.
Dubhe is a binary star (or possibly a trinary or quarternary). It lies 125 light years from Earth. It has 4.25 times the mass of the Sun. It has 30 times the radius of the Sun. It is a red-orange giant that is beginning to burn the iron at its core at a relatively cool 7600 degrees F. but it is 300 times as bright as the Sun. It's age is not known, but it is far along in its stellar life.
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