M4 with Alniyat Nebulosity: A diversity of stunning deep sky objects is summoned in this image: A bright star, a Globular Cluster and emission, reflection and dark nebulae.

The bright star in the left part of the image is Alniyat or Sigma Scorpii. Its powerful radiation excites the hydrogen gas in its neighbourhood to glow in the red H-alpha spectral line thus creating the beautiful emission nebula. In addition the radiation is reflected from dust particles generating an intense blue nebulosity around the star.The dark patches e.g. in the lower left corner are dark nebulae where the light cannot pentrate the dust clouds.

In the lower right is the Globular Cluster M4. quite close to the red super giant star Antares. With a distance to us of approx. 7000 LY it is one of the closest of all Globular Clusters.

See also the Hi-Res version, ecpecially for a closer inspection of M4.
For a wide-field mosaic of the Antares region see here.