Grus constellation Optical image of the constellations Grus the crane and Piscis Austrinis the southern fish North is at top The body of the crane is formed by the orange star at upper centre Beta Gruis Al Nair Alpha Gruis is just to its right The bright star at upper centre is Fomalhaut Alpha Piscis Austrini in the southern fish At lower left is the bright star Achernar Alpha Eridani in the constellation Eridanus the river This blue giant star is the ninth brightest star in the sky and lies around light years from Earth These southern constellations are best seen in spring from the southern hemisphere