Rho

Featuring the bright, red supergiant star Antares, the Rho Ophiuchi (oh'-fee-yu-kee) cloud complex is one of the most vibrant and colorful nebulas in space and the closest star-forming region to the solar system. The many spectacular colors of the Rho Ophiuchi 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.

 

Located approximately 460 light-years away from Earth, the interstellar clouds of gas and dust that make up Rho Ophiuchi contain emission nebulas that are rich with red, glowing hydrogen gas and blue reflection nebulas that reflect starlight from their surroundings.

 

 

Originally, astronomers believed the dark-brown regions in the cloud complex were areas in space where there were no stars, but it was later discovered that dark nebulae actually consist of clouds of interstellar dust so thick it can block out the light from the stars beyond.

 

 

Sony a7RII

SMC Pentax-A 645 150mm f/3.5

Vixen Polarie Star Tracker

 

74 Light frames

ISO 2500, 150mm, 60s at f/3.5

34 Dark Frames

62 Flat Frames

116 Bias Frames

 

Thanks to Andrew Klinger for stacking the images in PixInsight.

Processed in Capture One Pro and Adobe Photoshop

Imaged at Texas Astronomy Society’s Dark site in Atoka, Oklahoma.

Done