Figure B1-1.1 Angles and Angular Measure (a) Angles are measured in degrees (°). There are 360° in a complete circle and 90° in a right angle. For example, the angle between the vertical direction (directly above you) and the horizontal direction (toward the horizon) is 90°. The angular diameter of the full moon in the sky is about ½°. (b) The seven bright stars that make up the Big Dipper can be seen from anywhere in the northern hemisphere. The angular distance between the two “pointer stars” at the front of the Big Dipper is about 5°. (c) The four bright stars that make up the Southern Cross can be seen from anywhere in the southern hemisphere. The angular distance between the stars at the top and bottom of the cross is about 6°.