σ Ophiuchi (sigma Ophiuchi)
σ Ophiuchi is a variable bright giant star in the constellation of Ophiuchus.
σ Ophiuchi visual magnitude is 4.34. Because of its moderate brightness, σ Ophiuchi should be easily visible from locations with dark skies, while it can be barely visible, or not visible at all, from skies affected by light pollution.
The proper motion of σ Ophiuchi is 0.004 arcsec per year in Right Ascension and 0.007 arcsec per year in Declination and the associated displacement for the next 100000 years is represented with the red arrow.
Key facts about σ Ophiuchi
σ Ophiuchi (sigma Ophiuchi) is below the horizon from Greenwich, United Kingdom.
Altitude: -31.9°
Azimuth: 336.8°
Direction: North-North-West
Celestial coordinates and finder chart of σ Ophiuchi
σ 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 σ Ophiuchi are provided in the following table:
The simplified sky map below shows the position of σ Ophiuchi in the sky:
Visibility of σ Ophiuchi from your location
Location: Greenwich, United Kingdom
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London
Today's σ Ophiuchi (sigma Ophiuchi) rise, transit and set times from Greenwich, United Kingdom are the following (all times relative to the local timezone Europe/London):
Distance of σ Ophiuchi from the Sun and relative movement
σ Ophiuchi is distant 1,172.66 light years from the Sun and it is moving towards the Sun at the speed of 27 kilometers per second.
Spectral properties of σ Ophiuchi
σ Ophiuchi belongs to spectral class K2 and has a luminosity class of II corresponding to a bright giant star.
The red dot in the diagram below shows where σ Ophiuchi is situated in the Hertzsprung–Russell diagram.
