An abbreviated star trails shot using about 50 exposures. The multi-colored background light must be from Las Vegas, over 100 miles away. Because of this ambient light, the star trails don’t look as pronounced as when it is completely dark out. When you combine 50 exposures, you are combining the light from each as well. The boldest and brightest streak is Sirius, the brightest object in our night sky besides the Moon, other planets and our Sun.