APOD: 2026 September 21 – Cocoon Nebula Wide Field
APOD Science APOD APOD: 2026 September 21 –… Today’s APOD Archive Submissions Index Search Calendar RSS Education About Discuss APOD Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. Cocoon Nebula Wide Field Explanation: When does a nebula look like a comet? In this crowded starfield covering over two degrees within the high-flying constellation of the Swan ( Cygnus ), the eye is drawn to the Cocoon Nebula. A compact star forming region, the cosmic Cocoon punctuates a nebula bright in emission and reflection on the lower right, with a long trail of interstellar dust clouds to the left, making the entire complex appear a bit like a comet . Cataloged as IC 5146 , the central bright head of the nebula spans about 10 light years , while the dark dust y tail spans nea...
