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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:54  
clear_day Transit: 12:49  
SunsetSet: 18:43 south
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All Constellations » Eridanus » 

51 Eridani

Altitude: 14.6°   Azimuth: 113.6°   Direction: East-South-East

51 Eridani is a multiple hypergiant star in the constellation of Eridanus.

51 Eridani visual magnitude is 5.23. Because of its reltive faintness, 51 Eridani 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 51 Eridani:


51 Eridani is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 14.6°
Azimuth: 113.6°
Direction: East-South-East

Celestial coordinates and finder chart of 51 Eridani

51 Eridani 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 Eridani are provided in the following table:

04h 37m 36s
-02° 28’ 23”

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

Finder chart 51 Eridani star
Simplified finder chart for 51 Eridani.

Visibility of 51 Eridani 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 51 Eridani 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: 92.5°
Max altitude: 36.0°
Azimuth: 267.5°

Digitized Sky Survey image of 51 Eridani

The image below is a photograph of 51 Eridani 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 Eridani is 0.042 arcsec per year in Right Ascension and -0.061 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of 51 Eridani star
DSS2 image of 51 Eridani. The red arrow shows the motion of 51 Eridani during the next 10000 years (7.00 arcmin in Right Ascension and -10.17 arcmin in declination);

Distance of 51 Eridani from the Sun and relative movement

51 Eridani is distant 97.02 light years from the Sun and it is moving far from the Sun at the speed of 21 kilometers per second.

29.76 pc
97.02 ly
21 km/s
0.042 arcsec/year
-0.061 arcsec/year

Spectral properties of 51 Eridani

51 Eridani belongs to spectral class F0 and has a luminosity class of V corresponding to a hypergiant star.


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

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

51 Eridani star system properties

51 Eridani is a visual double star which can be observed with the help of small or medium telescopes. The table below shows key information about the 51 Eridani double sysyem:

80 arcsec

Alternative designations of 51 Eridani