Astronomy Picture of the Day . ... Gradually change the focus of the camera lens during the exposure, and you could end up with a dramatic picture like this one where the out-of-focus portion of the trail shows off the star's color . In this case, the subject is one of the most famous constellations in the night sky, Crux , the Southern Cross. ... Publications with keywords: Crux - Southern Cross - star trail . Publications with words: Crux - Southern Cross - star trail . ...