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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:55  
clear_day Transit: 12:49  
SunsetSet: 18:41 south
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All Constellations » Delphinus » 

Aldulfin - ε Delphini (epsilon Delphini)

Altitude: 37.7°   Azimuth: 235.0°   Direction: South-West

Aldulfin, also designated as ε Delphini (epsilon Delphini), is a variable giant star in the constellation of Delphinus.

Aldulfin visual magnitude is 4.03. Because of its moderate brightness, Aldulfin 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 Aldulfin:


Aldulfin - ε Delphini (epsilon Delphini) is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 37.7°
Azimuth: 235.0°
Direction: South-West

Celestial coordinates and finder chart of Aldulfin

Aldulfin 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 Aldulfin are provided in the following table:

20h 33m 12s
+11° 18’ 11”

The simplified sky map below shows the position of Aldulfin in the sky:

Finder chart Aldulfin - ε Delphini (epsilon Delphini) star
Simplified finder chart for Aldulfin - ε Delphini (epsilon Delphini).

Visibility of Aldulfin 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 Aldulfin - ε Delphini (epsilon Delphini) 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: 78.7°
Max altitude: 49.8°
Azimuth: 281.3°

Digitized Sky Survey image of Aldulfin

The image below is a photograph of Aldulfin 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 Aldulfin is 0.013 arcsec per year in Right Ascension and -0.022 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of Aldulfin - ε Delphini (epsilon Delphini) star
DSS2 image of Aldulfin. The red arrow shows the motion of Aldulfin during the next 10000 years (2.17 arcmin in Right Ascension and -3.67 arcmin in declination);

Distance of Aldulfin from the Sun and relative movement

Aldulfin is distant 358.64 light years from the Sun and it is moving towards the Sun at the speed of 19 kilometers per second.

110.01 pc
358.64 ly
-19 km/s
0.013 arcsec/year
-0.022 arcsec/year

Spectral properties of Aldulfin

Aldulfin belongs to spectral class B6 and has a luminosity class of III corresponding to a giant star.


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

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

Alternative designations of Aldulfin

ε Delphini
(epsilon Delphini)