Surprising Cloud Above Stargazers

From the photographer: “Just before my outdoor presentation at the annual Nightfall Star Party at the Palm Canyon Resort in Borrego Springs, CA, the southwestern sky lit up in a weird glow. We found out it was from a Trident II (D5) missile test launch from an Ohio-class submarine of the coast of San Diego, and was seen for many hundreds of miles. By the time I ran to the car to get my camera, however, the light had subsided and all that remained at 7:08 p.m. was this blue glow over the telescope field.” © Dennis Mammana