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Since the Little Dipper (technically called Ursa Minor) is not one of the brightest constellations in the sky, it may be
difficult to locate from urban areas. If this is the case, use the two end stars in the bowl of the Big Dipper (the pointer
stars). Draw an imaginary line through them toward the Little Dipper. They point to Polaris (see Figure 6-5). The
position of the Big Dipper changes during the year and throughout the course of the night (see Figure 6-5). When the
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 hemisphere are 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
star that is relatively bright is Sigma Octantis. This star is just within naked eye limit (magnitude 5.5) and lies about 59
arc minutes from the pole.
The north celestial pole is the point in the northern hemisphere around which all stars
appear to rotate. The counterpart in the southern hemisphere is referred to as the south
celestial pole.
Definition
Figure 6-6
The two stars in the front of the bowl of the Big Dipper point to Polaris which is less than
one degree from the true (north) celestial pole. Cassiopeia, the “W” shaped constellation,
is on the opposite side of the pole from the Big Dipper. The North Celestial Pole (N.C.P.)
is marked by the “+” sign.