The stars and constellations in the night sky appear to rotate around the North Star throughout the year. A common misconception about the North Star is that it is the brightest star in the sky, but that is not true. Polaris, or commonly known as The North Star is located almost directly above the North Celestial Pole, marking the way due north. Polaris is not the brightest star in the night sky. However, it is easily located making it a reliable gauge of North for travelers without a compass.
As you travel northward, Polaris climbs higher in the sky. If you go as far north as the North Pole, Polaris will appear directly overhead. As you travel south, Polaris drops closer to the northern horizon.
From the equator, Polaris sinks to the horizon and cannot be seen from the South of the equator. In the Northern Hemisphere, finding Polaris means you know the direction north. Even when the full moon obscures the sky, the North Star is relatively easy to see. The following video provides a basic overview of how to locate the North Star. Polaris is easy to find if you can first locate the Little Dipper , Ursa Minor.
Its extreme closeness to the far more brilliant Polaris A explains why it went unseen for so long. Exactly where you see Polaris in your northern sky depends on your latitude.
From New York it stands 41 degrees above the northern horizon, which also corresponds to the latitude of New York. Since 10 degrees is roughly equal to your clenched fist held at arm's length, from New York Polaris would appear to stand about "four fists" above the northern horizon.
At the North Pole, you would find it overhead. At the equator, Polaris would appear to sit right on the horizon. So if you travel to the north, the North Star climbs progressively higher the farther north you go.
When you head south, the star drops lower and ultimately disappears once you cross the equator and head into the Southern Hemisphere. And always keep this fact in mind: Polaris is more accurate than any compass.
A compass is subject to periodic variations and can only show you the direction of the lines of the strongest magnetic force for a particular spot and for a particular time. But even Polaris isn't positioned exactly due north. Only about 0.
In case you're wondering, 0. Aside from the North Star the two stars at the front of the Little Dipper's bowl are the only ones readily seen. Unfortunately, latitude alone is insufficient to pinpoint a location on the surface of the earth.
Lines of constant latitude circle the earth parallel to the equator. With only latitude in hand, an individual knows just that he or she is on a particular "latitude circle. Although many cultures succeeded in making long ocean voyages using only the stars, weather and currents, the "longitude problem" plagued sailors for millennia and remained unsolved until the invention of a clock that could keep accurate time while a ship rolled, pitched and yawed on the sea circa Furthermore, Polaris is not an absolute guide to measuring latitude on the earth for Northern Hemisphere observers.
In addition to the daily hour rotation cycle, the axis of the earth precesses in a conical motion. Thus, the projection of the earth's axis traces a circle in the northern and southern sky with a period of 26, years. The location of the North and South Celestial Pole is defined by projecting the axis of the earth onto the celestial sphere; consequently, as the axis changes position, so, too, does the "North Star.
Similarly, in 12, years the star Vega in the constellation Lyra will be the North Star. Some stars travel a great distance over the course of the night.
Polaris is different. Because it's so close to the celestial pole, it traces out a very small circle over 24 hours. So Polaris always stays in roughly the same place in the sky, and therefore it's a reliable way to find the direction of north. It would appear directly overhead if you stood at the north pole, but farther south, it indicated the direction of north. Locating Polaris is easy on any clear night.
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