HR7777

HR7777 is a variable main-sequence star in the constellation of Cygnus.

HR7777 visual magnitude is 6.45. Because of its reltive faintness, HR7777 should be visible only from locations with dark skyes, while it is not visible at all from skyes affected by light pollution.

The table below summarizes the key facts about HR7777:

Color of HR7777 ⬤

Magnitude of HR7777 6.45

Class Main-sequence

VISIBILITY RIGHT NOW HR7777 is above the horizon from Greenwich, United Kingdom edit_location_alt. Altitude: 75°.

Celestial coordinates and finder chart of HR7777

HR7777 is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of HR7777 are provided in the following table:

Right Ascension J2000 20h 18m 49s

Declination J2000 +46° 19’ 22”

Galactic Longitude 82.82°

Galactic Latitude 5.8°

Constellation Cygnus

The simplified sky map below shows the position of HR7777 in the sky:

Simplified finder chart for HR7777.

Visibility of HR7777 from your location

Location: Greenwich, United Kingdom edit_location_alt
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

HR7777 is circumpolar and transits at 03:49 UTC (altitude: 84.8°)

Digitized Sky Survey image of HR7777

The image below is a photograph of HR7777 from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of HR7777 is -0.005 arcsec per year in Right Ascension and 0.01 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

DSS2 image of HR7777. The red arrow shows the motion of HR7777 during the next 10000 years (-0.83 arcmin in Right Ascension and 1.67 arcmin in declination);

Distance of HR7777 from the Sun and relative movement

HR7777 is distant 2,650.41 light years from the Sun and it is moving towards the Sun at the speed of 9 kilometers per second.

Distance (parsec) 813.01 pc

Distance (light year) 2,650.41 ly

Heliocentric radial velocity -9 km/s

Proper Motion RA -0.005 arcsec/year

Proper Motion Dec 0.01 arcsec/year

Spectral properties of HR7777

HR7777 belongs to spectral class B2 and has a luminosity class of V corresponding to a main-sequence star.

Absolute magnitude -3.10

Spectral Type B2V

Color Index (B-V) -0.13

Temperature of HR7777 12103K

The red dot in the diagram below shows where HR7777 is situated in the Hertzsprung–Russell diagram.

H-R diagram showing the position of HR7777. Attribution: Richard Powell / CC BY-SA

Alternative designations of HR7777

Henry Draper Catalogue HD193536

SAO Catalogue SAO49462

Hipparcos Catalogue HIP100142

Durchmusterung Catalogue BD+45 3139

General Catalogue of Variable Stars V1773 Cyg

In Evidence

Other stars in Cygnus