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🌎  Greenwich, United Kingdom [change]

Gacrux - γ Crucis (gamma Crucis)

Gacrux, also designated as γ Crucis (gamma Crucis), is a variable and multiple giant star in the constellation of Crux.

Gacrux visual magnitude is 1.63, making it the 23th brightest star in the sky. Thanks to its high brightness, Gacrux is clearly visible when observed from locations with dark skyes, and should be also quite easily visible from light polluted areas.

The table below summarizes the key facts about Gacrux:

1.63
Giant
Gacrux - γ Crucis (gamma Crucis) is below the horizon from Greenwich, United Kingdom [change].

Celestial coordinates and finder chart of Gacrux

Gacrux is situated south of the celestial equator, as such, it is more easily visible from the southern emisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of Gacrux are provided in the following table:

12h 31m 09s
-57° 06’ 47”
300.17°
5.65°
Crux

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

Finder chart Gacrux - γ Crucis (gamma Crucis) star
Simplified finder chart for Gacrux - γ Crucis (gamma Crucis).

Visibility of Gacrux from your location

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

Gacrux - γ Crucis (gamma Crucis) is currently not visible from Greenwich, United Kingdom [change]

Digitized Sky Survey image of Gacrux

The image below is a photograph of Gacrux 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 Gacrux is 0.023 arcsec per year in Right Ascension and -0.262 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of Gacrux - γ Crucis (gamma Crucis) star
DSS2 image of Gacrux. The red arrow shows the motion of Gacrux during the next 1000 years (0.38 arcmin in Right Ascension and -4.37 arcmin in declination);

Distance of Gacrux from the Sun and relative movement

Gacrux is distant 87.89 light years from the Sun and it is moving far from the Sun at the speed of 21 kilometers per second.

26.96 pc
87.89 ly
21 km/s
0.023 arcsec/year
-0.262 arcsec/year

Spectral properties of Gacrux

Gacrux belongs to spectral class M3 and has a luminosity class of III corresponding to a giant star.

-0.52
M3III
3663K

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

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

Gacrux star system properties

Gacrux 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 Gacrux double sysyem:

1.63
6.73
5.1
110.6 arcsec

Alternative designations of Gacrux

Gacrux
γ Crucis
(gamma Crucis)
SAO240019
SAO240019