This is a combination of 16 exposures of 4 minutes each with a Nikon D300 and a Sigma 500mm f/4.5 lens. It was taken on a clear, dry and transparent night at Harrington Beach State Park in Lake Church, Wisconsin. I used a Losmandy G11 mount and guided with an Imaging Source DMK-31 firewire camera and PHD guiding software, using a Macbook. The images were layered and processed in Photoshop CS3.