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Gamma Crucis

Proper NameGacrux
Bayer DesignationGamma Crucis
Flamsteed NumberNone
HR (BSC)4763
Right Ascension12h 31m 10s
Declination-57° 6' 48"
Distance89 light years
27 parsecs
MagnitudeApparent: +1.6 to +1.7
Absolute: -0.6 to -0.5
Spectral ClassM4 Red Giant
Optimum VisibilityApril (Usually visible from southern latitudes)
NotesThe third brightest of the stars that make up Crux the Cross, the red colouration of Gacrux contrasts against the three blue stars that make up the Cross' other three arms. There is indirect evidence that Gacrux has a white dwarf companion, though this companion has yet to be directly observed.

Imagery provided by Aladin sky atlas

Relative Galactic Position of Gacrux

The Galactic position and direction of Gacrux relative to Earth's Sun. Note that, at this extreme scale, the two stars are effectively in the same place.

The crowning star of the Southern Cross is Gacrux or Gamma Crucis, 89 light years (27 parsecs) from Earth. This is a red giant star, indicating that it is reaching the end of its stellar lifespan. It is a binary (that is, it has an less luminous and smaller companion star), and is also variable - its brightness changes over time.


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