Your Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:49  
clear_day Transit: 12:50  
SunsetSet: 18:50 south
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All Constellations » Serpens » 

σ Serpentis (sigma Serpentis)

Altitude: 17.9°   Azimuth: 247.9°   Direction: West-South-West

σ Serpentis is a hypergiant star in the constellation of Serpens.

σ Serpentis visual magnitude is 4.82. Because of its moderate brightness, σ Serpentis 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 σ Serpentis:

4.82
Hypergiant

σ Serpentis (sigma Serpentis) is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 17.9°
Azimuth: 247.9°
Direction: West-South-West

Celestial coordinates and finder chart of σ Serpentis

σ Serpentis 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 Serpentis are provided in the following table:

16h 22m 04s
+01° 01’ 45”
14.78°
33.22°
Serpens

The simplified sky map below shows the position of σ Serpentis in the sky:

Finder chart σ Serpentis (sigma Serpentis) star
Simplified finder chart for σ Serpentis (sigma Serpentis).

Visibility of σ Serpentis from your location

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

Today's σ Serpentis (sigma Serpentis) rise, transit and set times from Greenwich, United Kingdom edit_location_alt are the following (all times relative to the local timezone Europe/London):

Azimuth: 89.0°
Max altitude: 39.5°
Azimuth: 271.0°

Digitized Sky Survey image of σ Serpentis

The image below is a photograph of σ Serpentis 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 σ Serpentis is -0.155 arcsec per year in Right Ascension and 0.05 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of σ Serpentis (sigma Serpentis) star
DSS2 image of σ Serpentis. The red arrow shows the motion of σ Serpentis during the next 1000 years (-2.58 arcmin in Right Ascension and 0.83 arcmin in declination);

Distance of σ Serpentis from the Sun and relative movement

σ Serpentis is distant 89.17 light years from the Sun and it is moving towards the Sun at the speed of 50 kilometers per second.

27.35 pc
89.17 ly
-50 km/s
-0.155 arcsec/year
0.05 arcsec/year

Spectral properties of σ Serpentis

σ Serpentis belongs to spectral class F0 and has a luminosity class of V corresponding to a hypergiant star.

2.64
F0V
7217K

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

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

Alternative designations of σ Serpentis

σ Serpentis
(sigma Serpentis)
50 Serpentis
SAO121540
SAO121540