The Northern Cross

Take a closer look at Deneb, the northernmost and faintest star in the Summer Triangle. Off to the south, or the right, of Deneb are three stars. The middle star is labeled Sadr in the chart above. Farther to the south, or right, is the fainter star Albireo.

These stars make up what is known as the Northern Cross. Deneb marks the top of the cross. Sadr is at the intersection of the arms of the cross, and Albireo is at the bottom of the cross.

Deneb to Albireo spans 22°. If you hold your outstretched hand at arm's length against the sky, the width from your thumb to your little finger covers about 25°. The Northern Cross should fit within your outstretched hand.

References:

Constellation Cygnus
Star Science in the Autumn Sky