77 Cygni

Above the horizon. Circumpolar today

Alt: 3.99° Az: 346.54° Direction: North-North-West

77 Cygni is a double hypergiant star of spectral class A0 in the constellation of Cygnus.

77 Cygni visual magnitude is 5.69. Because of its faintness, 77 Cygni is visible to the naked eye only from locations with very dark skies, while it is not visible at all from skies affected by light pollution.

DSS2 image of 77 Cygni. The red arrow shows the motion of 77 Cygni during the next 10000 years (3.50 arcmin in Right Ascension and 0.50 arcmin in declination);

Celestial Coordinates

Apparent

Right Ascension 21h 43m 24s

Declination +41° 11’ 38”

Hour Angle 10h 48m 06s

Sidereal Time 08h 31m 30s

J2000

Right Ascension 21h 42m 22s

Declination +41° 04’ 37”

Galactic Coordinates

Galactic Longitude 88.84°

Galactic Latitude -8.96°

Finder Chart

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Finder chart for 77 Cygni.

Magnitude, Color, Spectral Class

Color ⬤

Magnitude 5.69

Class Hypergiant

Absolute magnitude 0.40

Spectral Type A0V

Color Index (B-V) 0.01

Temperature 10002K

The red dot in the diagram below shows where 77 Cygni is situated in the Hertzsprung–Russell diagram.

H-R diagram showing the position of 77 Cygni. Attribution: Richard Powell / CC BY-SA

Star System Properties

77 Cygni is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the 77 Cygni double sysyem:

Main star magnitude 5.69

Secondary star magnitude 5.89

Magnitude difference 0.2

Separation 0.1 arcsec

Distance, Radial Speed, Proper Motion

77 Cygni is distant 372.15 light years from the Sun and it is moving towards the Sun at the speed of 25 kilometers per second.

Distance (parsec) 114.16

Distance (light year) 372.15

Radial Speed -25 km/s

Proper Motion RA 0.021 arcsec/y

Proper Motion Dec 0.003"/y

Alternative Designations

Flamsteed designation 77 Cygni

Henry Draper Catalogue HD206644

SAO Catalogue SAO51207

Hipparcos Catalogue HIP107162

Durchmusterung Catalogue BD+40 4615

Visibility from Your Location

77 Cygni is circumpolar and transits at 06:10 UTC (altitude: 79.7°)

Set Location

Other stars in Cygnus