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public LocationGreenwich, UK
TimezoneEurope/London
Sunrise: 4:43 
Transit: 13:01 
Sunset: 21:18
wb_twilight   (Nautical Twilight)   What's Visible Now?
All Constellations » Ophiuchus » 

73 Ophiuchi

Above the horizon.  Rise: 18:33 | Tran: 0:51 | Set: 7:13
Altitude: 33.3°   Azimuth: 226.2°   Direction: South-West

73 Ophiuchi is a variable and multiple main-sequence star of spectral class F2 in the constellation of Ophiuchus.

73 Ophiuchi visual magnitude is 5.73. Because of its faintness, 73 Ophiuchi 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.

Celestial coordinates and finder chart of 73 Ophiuchi

Finder chart 73 Ophiuchi star
Simplified finder chart for 73 Ophiuchi.

73 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 73 Ophiuchi are provided in the following table:

18h 09m 33s
+03° 59’ 35”
31.72°
11.13°
Ophiuchus
Image of 73 Ophiuchi star
DSS2 image of 73 Ophiuchi. The red arrow shows the motion of 73 Ophiuchi during the next 10000 years (6.33 arcmin in Right Ascension and -1.17 arcmin in declination);

Key facts about 73 Ophiuchi

5.73
Main-sequence

and has a luminosity class of V corresponding to a main-sequence star.

2.19
F2V
7044K

The red dot in the diagram below shows where 73 Ophiuchi is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of 73 Ophiuchi. Attribution: Richard Powell / CC BY-SA

73 Ophiuchi star system properties

73 Ophiuchi 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 73 Ophiuchi double sysyem:

5.73
6.93
1.2
0.3 arcsec

Distance of 73 Ophiuchi from the Sun and relative movement

73 Ophiuchi is distant 166.16 light years from the Sun and it is moving towards the Sun at the speed of 17 kilometers per second.

50.97 pc
166.16 ly
-17 km/s
0.038 arcsec/year
-0.007 arcsec/year

Alternative designations of 73 Ophiuchi

73 Ophiuchi
SAO123187
SAO123187

Visibility of 73 Ophiuchi from your location

Today's 73 Ophiuchi rise, transit and set times from Greenwich, UK are the following (all times relative to the local timezone Europe/London):

Azimuth: 86.0°
Max altitude: 42.5°
Azimuth: 274.0°