51 Ophiuchi

51 Ophiuchi is a variable main-sequence star in the constellation of Ophiuchus.

51 Ophiuchi visual magnitude is 4.81. Because of its moderate brightness, 51 Ophiuchi should be easily visible from locations with dark skyes, while it can be barely visible, or not visible at all, from skyes affected by light pollution.

The table below summarizes the key facts about 51 Ophiuchi:

Color of 51 Ophiuchi ⬤

Magnitude of 51 Ophiuchi 4.81

Class Main-sequence

VISIBILITY RIGHT NOW 51 Ophiuchi is above the horizon from Greenwich, United Kingdom [change]. Altitude: 11°.

Celestial coordinates and finder chart of 51 Ophiuchi

51 Ophiuchi is situated close to the celestial equator, as such, it is at least partly visible from both hemispheres in certain times of the year. Celestial coordinates for the J2000 equinox as well as galactic coordinates of 51 Ophiuchi are provided in the following table:

Right Ascension J2000 17h 31m 24s

Declination J2000 -23° 57’ 46”

Galactic Longitude 2.52°

Galactic Latitude 5.34°

Constellation Ophiuchus

The simplified sky map below shows the position of 51 Ophiuchi in the sky:

Simplified finder chart for 51 Ophiuchi.

Visibility of 51 Ophiuchi from your location

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

Today's 51 Ophiuchi rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 114.0° RISE 2:22

Max altitude: 14.6° TRANSIT 6:06

Azimuth: 246.0° SET 9:49

RIGHT NOW 51 Ophiuchi is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of 51 Ophiuchi

The image below is a photograph of 51 Ophiuchi 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 51 Ophiuchi is 0.004 arcsec per year in Right Ascension and -0.027 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

DSS2 image of 51 Ophiuchi. The red arrow shows the motion of 51 Ophiuchi during the next 10000 years (0.67 arcmin in Right Ascension and -4.50 arcmin in declination);

Distance of 51 Ophiuchi from the Sun and relative movement

51 Ophiuchi is distant 426.14 light years from the Sun and it is moving towards the Sun at the speed of 12 kilometers per second.

Distance (parsec) 130.72 pc

Distance (light year) 426.14 ly

Heliocentric radial velocity -12 km/s

Proper Motion RA 0.004 arcsec/year

Proper Motion Dec -0.027 arcsec/year

Spectral properties of 51 Ophiuchi

51 Ophiuchi belongs to spectral class B9 and has a luminosity class of V corresponding to a main-sequence star.

Absolute magnitude -0.77

Spectral Type B9V

Color Index (B-V) 0

Temperature of 51 Ophiuchi 10125K

The red dot in the diagram below shows where 51 Ophiuchi is situated in the Hertzsprung–Russell diagram.

H-R diagram showing the position of 51 Ophiuchi. Attribution: Richard Powell / CC BY-SA

Alternative designations of 51 Ophiuchi

Flamsteed designation 51 Ophiuchi

Henry Draper Catalogue HD158643

SAO Catalogue SAO185470

Hipparcos Catalogue HIP85755

Durchmusterung Catalogue CD-2313412

General Catalogue of Variable Stars 9037

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Other stars in Ophiuchus