δ Cygni


Delta Cygni is a triple star system in which companion B orbits the primary every 827.6 years:
      AB: 2.9, 6.3; 225, 2.5" (blue-white/yellow).
      AC: 2.9, 12.0; 67, 63" (orange)

Delta Cygni will become the North Star in about 11,500 years, and will remain so for about 400 years.

Two degrees northwest of delta is the open cluster NGC 6811.
      NGC 6811 is about 3600 light years away.
      It may be a billion years old; it has an apparent magnitude of 6.8
      Over a thousand stars are in the cluster, the most visible being equal-magnitude bluish-white stars.
      In binoculars the cluster is a hazy area; in small telescopes the cluster is resolvable.
     Two planets have been discovered in the cluster (Kepler 66b and Keplet 67b).

With delta centred, move about one and a half fields southeast until gamma Cyg is centred. Click on gamma Cygni on the map to continue.

All files associated with The Constellations Web Page are
1998-2014 by Richard Dibon-Smith.