Astronomy Picture of the Day

Explanation: A dramatic study in contrasts, this colourful skyscape features stars, dust, and glowing gas in NGC 6914. The complex of nebulae lies some 6,000 light-years away, toward the high-flying northern constellation Cygnus and the plane of our Milky Way Galaxy. With foreground dust clouds in silhouette, both reddish hydrogen emission nebulae and dusty blue reflection nebulae fill the 1/2 degree wide field. The view spans nearly 50 light-years at the estimated distance of NGC 6914. Ultraviolet radiation from the massive, hot, young stars of the extensive Cygnus OB2 association ionize the region's atomic hydrogen gas, producing the characteristic red glow as protons and electrons recombine. Embedded Cygnus OB2 stars also provide the blue starlight strongly reflected by the dusty clouds. Constructed as a two-panel mosaic, the image was processed to bring out both bright and dim colours and detailed structures.