Object: Rho Ophiuchi Nebulae Complex
Date: 6/02/08, ~12:30 -2am 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 200mm lens stopped to f/3.5
Exposure: 20 x 5 minutes, ISO800
Processing: Registered and stacked (Sigma Clipped Median) in ImagesPlus. Final levels and curves in PS. 
Comments: The many spectacular colors of the Rho Ophiuchi (oh'-fee-yu-kee) clouds highlight the many processes that occur there. The blue regions shine primarily by reflected light. Blue light from the star Rho Ophiuchi and nearby stars reflects more efficiently off this portion of the nebula than red light. The Earth's daytime sky appears blue for the same reason. The red and yellow regions shine primarily because of emission from the nebula's atomic and molecular gas. Light from nearby blue stars - more energetic than the bright star Antares - knocks electrons away from the gas, which then shines when the electrons recombine with the gas. The dark regions are caused by dust grains - born in young stellar atmospheres - which effectively block light emitted behind them. The Rho Ophiuchi star clouds, well in front of the globular cluster M4, are even more colorful than humans can see. The clouds emits light in every wavelength band from the radio to the gamma-ray. (Comments from APOD website.)

© Dave Dockery 2008