The celestial poles

wait a little ... and watch the animation below !

Clotilde

 

Southern Cross

 

Crux, commonly known as the Southern Cross, is a constellation you can only see in the southern hemisphere sky. It is very easy to find even though it's the smallest of all 88 modern constellations. The animation above shows the night sky in Reunion Island. Every picture was taken with one-minute intervals, starting at 15:45 to 16:00 (universal time coordinated). 

The Southern Cross appears in red in the first photo and you can see its movement in the gif.

 

Evana and Inès.

How to find the celestial south pole ?

 

With the Southern Cross (Crux): We can extend the straight line between α of Centaur(closest     star to the Earth) and α of Cir ( brightest star of the compas constelletion) until the straight       line between α Apus and δ Octans. And the point where the two straight lines cross them, is   the closest point of the celestial south pole. You can see the crossing between the two              straight lines on the picture below.                                                                                                                              

 

                                                                                                                           Mélissa.