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Since the Little Dipper (technicallycalled Ursa Minor) is not one of the brightest constellations in the sky, it may be
difficultto locate from urban areas. Ifthis is the case, use the two end stars in the bowl of the Big Dipper (the pointer
stars). Draw an imaginary line throughthem toward the Little Dipper. They point to Polaris (see Figure 6-5). The
positionof the Big Dipper changes during the year and throughout the course of the night (see Figure 6-5). Whenthe
Big Dipper is low in the sky (i.e., near the horizon), it may be difficult to locate. During these times, look for
Cassiopeia (see Figure 6-6). Observers in the southern hemisphereare not as fortunate as those in the northern
hemisphere. The stars around the south celestial pole are not nearly as bright as those around the north. The closest
starthat is relatively bright is Sigma Octantis. This star is just within naked eye limit (magnitude 5.5) and lies about 59
arcminutes from the pole.
Thenorth celestial pole is the point in the northern hemisphere around which all stars
appearto rotate. The counterpart in the southernhemisphere is referred to as the south
celestialpole.
Definition
Figure6-6
Thetwo stars in the front of the bowl of the Big Dipper point to Polaris which is less than
onedegree from the true (north) celestial pole. Cassiopeia,the “W” shaped constella tion,
ison the opposite side of the pole from the Big Dipper. TheNorth Celestial Pole (N.C.P.)
ismarked by the “+” sign.