Your hand held at arm's length is a convenient instrument for estimating the angular separation of objects in the night sky.

Practice this technique on the stars of the Southern Cross and the Pointers. Approximate angular distances between selected stars are given on the photo. The red circle represents the view through 10 x 50 binoculars with a 6.5° fov.

Note: the Moon is approximately half a degree across - equivalent to a pea balanced on the tip of one's thumb.