Your guide to the Solar System and the night sky
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🌎  Observing from: Greenwich, United Kingdom [change]
🌅 Sunrise: 6:43  ☀️ Transit: 13:03  🌅 Sunset: 19:24

Algedi - α2 Capricorni (alpha2 Capricorni)

Algedi, also designated as α2 Capricorni (alpha2 Capricorni), is a multiple giant star in the constellation of Capricornus.

Algedi visual magnitude is 3.57. Because of its moderate brightness, Algedi 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 Algedi:

3.57
Giant
Algedi - α2 Capricorni (alpha2 Capricorni) is below the horizon from Greenwich, United Kingdom [change].

Celestial coordinates and finder chart of Algedi

Algedi 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 Algedi are provided in the following table:

20h 18m 03s
-12° 32’ 40”
31.1°
-24.81°
Capricornus

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

Finder chart Algedi - α2 Capricorni (alpha2 Capricorni) star
Simplified finder chart for Algedi - α2 Capricorni (alpha2 Capricorni).

Visibility of Algedi from your location

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

Today's Algedi - α2 Capricorni (alpha2 Capricorni) rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 102.5°
Max altitude: 26.0°
Azimuth: 257.5°
Algedi - α2 Capricorni (alpha2 Capricorni) is below the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of Algedi

The image below is a photograph of Algedi 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 Algedi is 0.064 arcsec per year in Right Ascension and 0.004 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of Algedi - α2 Capricorni (alpha2 Capricorni) star
DSS2 image of Algedi. The red arrow shows the motion of Algedi during the next 10000 years (10.67 arcmin in Right Ascension and 0.67 arcmin in declination);

Distance of Algedi from the Sun and relative movement

Algedi is distant 108.63 light years from the Sun

33.32 pc
108.63 ly
0.064 arcsec/year
0.004 arcsec/year

Spectral properties of Algedi

Algedi belongs to spectral class G8 and has a luminosity class of III corresponding to a giant star.

0.96
G8III
4892K

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

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

Algedi star system properties

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

3.57
3.97
0.4
377.7 arcsec

Alternative designations of Algedi

Algedi
α2 Capricorni
(alpha2 Capricorni)
6 Capricorni
SAO163427
SAO163427