These star trails were photographed in south Texas at 30 degrees north latitude. Orion is in the center, as in the previous image. Latitude explains why these trails are slanted. Near the equator, in East Africa, stars in the eastern sky trail directly up and over your head. At higher latitudes, as here, you are tilted with respect to the rotating "sphere" of the sky. At either pole the stars would go around the horizon. This sky is blue, photographed with the same lens as the previous image and on the same emulsion (Provia 100), processed by the same photo lab.
© Gregory G. and Mary Beth Dimijian