The image above is of the circumpolar constellation Ursa Minor or "The Little Dipper" as it is commonly known, which was listed by Ptolemy as apart of his list of 48 constellations. The second magnitude star Polaris, which marks the north celestial pole at this time but will later shift location, is clearly visible at the center of left hand side. Although it is not the brightest star in the night sky (it is actually the 48th brightest), it is the brightest star of its neighbors in this photo and it is the brightest Cepheid variable star. Cepheid variable stars like Polaris are important to Astronomers because a relationship exists between their absolute magnitude and pulsation period that enables us to determine their distances and therefore, the distances to other galaxies!
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