Antares - Rho Ophiuchi area

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About this Image

This area around the yellow supergiant Antares, some 700 times larger in diameter than the Sun, is one of the most colorful ones in the sky.
The supergiant red Antares (Alpha Scorpii) in the upper part of this image is embedded in dust, showing the same color, superimposed by faint red glow from ionized Hydrogen.
In the lower part of the image lies the star Rho Ophiuchi embedded in the blue reflection nebula and dust (IC 4604).
The star in the red region on the left side is Sigma Scorpii; just left of Antares is the globular cluster M 4. Within the dense dark dust lanes young stars are born, visible in the far IR. The distance to Antares is approx. 520 light years.
North is down.


Technical Details
Optics

Canon 200mm EF L lens fully open at f/2.8

Mount AP-400 GEM
Camera SBIG STL-11000M at -25C, internal filter wheel
Filters Astronomik HaLRGB
Date May 23, 2006.
Location Hakos/Namibia
Sky Conditions mag 6.5, good transparency, temperature 8 C,
Exposure Ha:L:R:G:B= 70:100:60:40:60 min (5 min subs for L, other 10-minutes)
all 1x1.
Processing Image aquisition in Maxim DL 4.5; Image calibration and preprocessing in CCDStack;
Photoshop: curves, color balance;