Southern Cross

Southern Cross

With the lack of a significant pole star in the southern sky (Sigma Octantis is closest to the pole, but is so faint as to be useless for the purpose), two of the stars of Crux (Alpha and Gamma, Acrux and Gacrux respectively) are commonly used to mark south. Following the line defined by the two stars for approximately 4.5 times the distance between them leads to a point close to the Southern Celestial Pole.

Lens : 50mm
Exposure Time : 5 minutes + 1 with diffuse filter
Camera: Canon 10D
Date : August 2006
Guiding : Telescope piggyback
Location : Kaituna, Masterton