Russian photographer Maxim Korotchenko happened to catch these curious formation on the night sky over the city of Astrakhan, on June 7, 2012. The unusual glow, like the northern lights, hung over the city for about half and hour before fading away. The serpentine trail is likely to be caused by the test launch of a ballistic missile "Topol".
Sometimes when the weather, the time and the light is just about right, rocket launches can leave spectacular trails over the sky. It’s called twilight phenomenon.
Twilight phenomenon is produced when unburned particles of missile or rocket propellant and water left in the vapor trail of a launch vehicle condenses, freezes and then expands in the less dense upper atmosphere. The exhaust plume, which is suspended against a dark sky is then illuminated by reflective high altitude sunlight, which produces a spectacular, colorful effect when seen at ground level. The phenomenon typically occurs with launches that take place either 30 to 60 minutes before sunrise or after sunset when a booster rocket or missile rises out of the darkness and into a sunlit area, relative to an observer's perspective on the ground.
This phenomenon usually produces a cloud of green, blue, white and rose colored hues which takes on a corkscrew appearance as it is whipped around by wind currents. It is seen within two to three minutes after a launch has occurred. Depending on weather conditions, it could remain in the sky for up to half an hour before dispersing.
Apparently, missile launch over populated cities is common in Russia. Here is another series of spectacular twilight phenomenon captured at an unknown location in Russian in 2011.