Space Shuttle Discovery being chased by the International Space Station
The right-hand streak of light is from the last visible pass of the Space Shuttle Discovery (STS-133) over Southern California. The left-hand streak of light is from the International Space Station, which was trailing the Shuttle by approximately 45 seconds. There is also a pulsed light streak in the upper left-hand corner of the picture from a passing airplane.
This was created by stacking eight 30-second exposures in GIMP. The gaps in the streaks are as a result of the brief recycle time between frames.