While the parade of constellations continue to introduce themselves in the east, pass over and bid farewell in the west, there is always a bunch in the north that won’t go away. Not that we want them to; centered on the North Star, six constellations continually circle, never dropping below the horizon, as seen from mid-northern latitudes.

While the parade of constellations continue to introduce themselves in the east, pass over and bid farewell in the west, there is always a bunch in the north that won’t go away. Not that we want them to; centered on the North Star, six constellations continually circle, never dropping below the horizon, as seen from mid-northern latitudes.


The North Star, otherwise referred to as Polaris or by (thankfully) very few as Alpha Ursae Minoris, is a star in the right place at the right time. Some have the mistaken idea that the North Star is specially bright. Actually, it is a common star, which happens to be located very near where the North Celestial Pole is found.


This is the imaginary spot on the sky where the axis of Earth’s rotation points. An imagined line right through the South Pole, Earth’s center and the North Pole, aims right at this spot, located within one degree of Polaris.


In fact, the North Star hasn’t always enjoyed this status or attention. The Earth has an excruciatingly slow wobble as it spins. Each wobble takes approximately 25,800 years to go once around, meaning in that time span, the North Celestial Pole makes a complete circle on the northern sky. This is known as “Precession of the Equinoxes.” Through the millennia, different stars have been associated as the “North Star.” When the Egyptians were making their pyramids, the star Thuban in the constellation Draco the Dragon was the North Star. That was about 5,000 years ago.


Around 3000 A.D., the naked-eye star Gamma Cephei (Alrai) in Cepheus the King, will be closer to the North Celestial Pole than Polaris. Will our descendants change the names of the stars so Gamma Cephei becomes the new Polaris?


Meanwhile, we celebrate our North Star, which our forefathers actually used to help guide them in their travels. There was a time when it wasn’t just a Boy Scout or Girl Scout lesson, but a necessary thing to know, especially if you lived in the countryside and might be out at night.


It is also very useful for determining your latitude north of the equator; the top of my home of Wayne County, Pa., is at +42 degrees North Latitude. From that line, the North Star is very near +42 degrees above the north horizon. It is straight overhead (at the zenith) at the North Pole.


The star marks the end of the “handle” of the Little Dipper, a star group known officially by another name - Ursa Minor, the Little Bear. Generally, the Greek alphabet was used to designate constellation stars in order of their brightness. Thus, Polaris, being the brightest star in Ursa Minor, is labeled Alpha, for the first letter in the Greek alphabet.


Polaris is very nearly 2nd magnitude (+1.97 and slightly variable). A small telescope will show that Polaris is a double star, with a fainter companion star very close by. Polaris is about 434 light years from the sun.


The celestial poles differ with each planet in the solar system. From Mars, the bright star Deneb in Cygnus the Swan is close enough to be considered the “North Star.”


Alas, there is no recognized “South Star” in the southern hemisphere, there being no bright stars close by the South Celestial Pole - at least not yet.


Full moon is on April 17.


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Keep looking up!