Identifying and Understanding the North Star

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"Identifying and Understanding the North Star"
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In order to identify and fully appreciate the North Star we need to understand it, yet in order to understand it we need to be able to accurately identify it. A dilemma of sorts for many, excluding dedicated astronomers whose lives have been spent quietly wrapped around these little mysteries of the North Star that has dogged society throughout the years. Is it possible to do both simultaneously? That depends...

Over the years the North Star has fascinated everyone because it does not seem to move in the sky. Early cultures have developed folklore and legends to explain this unknown phenomenon, developed by those with little astronomy knowledge or more knowledgeable astronomers.

One of the most fascinating myths is of the Native American culture which explains why the North Star does not appear to move. According to the legend, a very young man by the name of Na-Gah desired to impress his father by climbing the tallest cliff he could find. On a very exhausting and dangerous journey, he eventually finds himself on the peak of the highest mountain which looked down on surrounding mountains.

As time goes by, the father of Na-Gah becomes worried as he does not hear from his son. One day he sees him on top of the high mountain. As the boy cannot come down, the father turns Na-Gah into a star rather than allow his son to suffer, to be seen and honored of all living things throughout eternity.

As science has developed and became more available, the star Polaris or North Star has been found as a fascinating binary star system. The North Star is easy to locate because of its northern location as the brightest star toward the end of the little dipper's handle. More technically, its line of direction has been a 5,000-year moving process from the star Thuban, or Alpha Draconic (in the Draco constellation), toward the bright star Polaris within one-degree. This is also known as the Alpha Ursae Minoris in the constellation Ursa Minor.

Sailors and travelers have used the North Star to navigate for centuries, charting navigation routes and determining true astronomic latitude, as it was thought to be a steady and solitary point of light. More technically, Internet searches will bring up the fact that " the celestial poles change as the axis of the Earth moves, traveling with the earth's precessional motion.

The north celestial pole assumes different positions relative to the constellation. As this process goes on, different stars will become the North Star." Technology facts themselves cannot be changed, regardless which website it is on, but they can be added to with theories changing on a steady basis. Unique as it is, Thuban became the North Star approximately 5,000 years ago but five thousand years from now it will be Alpha Cephei. Another seven thousand years will cause the North Star to become Vega, while another nine thousand years the North Star will return as Thuban.

For the first time ever NASA's Hubble Space Telescope has photographed a close companion to Polaris. This telescope has pointing capabilities which are superb, allowing scientists and astronomers to view the universe in high detail. The images sent back to Earth have not disproved the "sailor's myths" of its navigational powers but instead has added to it. What has been discovered by the Hubble is that the North Star is a triple star system, not just one beacon of light. The close proximity of the stars to each other triples its brightness for Earth viewers, at a distance of 430-light years from Earthor a separation of two billion miles.

NASA and astronomers are moving onward to another goal since this recent Hubble discovery, which is to obtain Polaris's accurate mass. This will require the measurement of the motion of the North Stars' companion. The reason this is so important is because it is the nearest Cepheid variable star. Not an unusual process, Cepheid is used many times because of its brightness variations. The distances of galaxies and the expansion of the universe are measured with it in order to understand evolution and its intrinsic physics makeup.

More about this author: Nancy Houser

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