Object: Rho Ophiuchi Nebulae Complex
Date: 6/07/08, ~12-1am CST
Location: Texas Star Party - near Fort Davis, TX.
Guiding: Camera was mounted side by side on a G11 mount with a TV85 refractor guided using an ST10.
Camera: Modified Canon 350XT using a Canon 100mm lens stopped to f/3.5
Exposure: 14 x 5 minutes, ISO800
Processing: Registered and stacked (Sigma Clipped Median) in ImagesPlus. Final levels and curves in PS. 
Comments: Why is the sky near Antares and Rho Ophiuchi so colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark. Antares, a red supergiant and one of the brighter stars in the night sky, lights up the yellow-red clouds on the left. Rho Ophiuchi lies at the center of the blue nebula on the right. The distant globular cluster M4 is visible just above Antares, and to the left of the red cloud engulfing Sigma Scorpii. (Comments from APOD website.)

© Dave Dockery 2008