This region of the sky looks like it contains a comet when viewed in binoculars. In this view the "comet" is seen to be made up of stars and star clusters. The star cluster NGC 6231 forms the “head” of the comet; the large open cluster Trumpler 24 forms the tail. While cataloged as separate clusters, these stars are physically associated and formed out of the same massive nebula only 6-8 million years ago. The collection is roughly 6,000 light years from Earth. The red nebulosity is from emission nebula IC4628.
Details
Early morning of 2011-03-02 at La Ensenada lodge, Costa Rica.
Very clear night with excellent seeing, 25 deg C, no wind.
Astrotrac mounted f/6 80mm Orion refractor with modified Canon T1i camera.
Exposure - 21 light and 40 dark frames at ISO 400 for 120s each.
Processing in Images Plus and Photoshop.