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: 4:52  
clear_day Transit: 12:55  
SunsetSet: 20:59 south
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Breakng! newly discovered Supernova 2023ixf in the Pinwheel Galaxy is the closest supernova observed in the latest decade. It can become bright enough to be visible by amateur astronomers. Check out information and detailed finder chart.
All Constellations » Libra » 

ο Librae (omicron Librae)

ο Librae is a double hypergiant star in the constellation of Libra.

ο Librae visual magnitude is 6.3. Because of its reltive faintness, ο Librae 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 ο Librae:

ο Librae (omicron Librae) is above the horizon from Greenwich, United Kingdom edit_location_alt. Altitude: 18°.

Celestial coordinates and finder chart of ο Librae

ο Librae 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 ο Librae are provided in the following table:

15h 21m 01s
-15° 32’ 53”

The simplified sky map below shows the position of ο Librae in the sky:

Finder chart ο Librae (omicron Librae) star
Simplified finder chart for ο Librae (omicron Librae).

Visibility of ο Librae 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 ο Librae (omicron Librae) 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: 105.5°
Max altitude: 23.0°
Azimuth: 254.5°
ο Librae (omicron Librae) is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of ο Librae

The image below is a photograph of ο Librae 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 ο Librae is 0.024 arcsec per year in Right Ascension and 0.026 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of ο Librae (omicron Librae) star
DSS2 image of ο Librae. The red arrow shows the motion of ο Librae during the next 10000 years (4.00 arcmin in Right Ascension and 4.33 arcmin in declination);

Distance of ο Librae from the Sun and relative movement

ο Librae is distant 178.04 light years from the Sun and it is moving far from the Sun at the speed of 5 kilometers per second.

54.61 pc
178.04 ly
5 km/s
0.024 arcsec/year
0.026 arcsec/year

Spectral properties of ο Librae

ο Librae belongs to spectral class F0 and has a luminosity class of III corresponding to a hypergiant star.


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

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

ο Librae star system properties

ο Librae is a visual double star which can be observed with binoculars or small telescopes. The table below shows key information about the ο Librae double sysyem:

44.4 arcsec

Alternative designations of ο Librae

ο Librae
(omicron Librae)