APOD: 2026 October 2 – The Complete Sharpless Catalog: 313 Nebulas

Today's APOD presents the entire Sharpless Catalog of H II Regions—313 objects—in a single image, inviting viewers to zoom in and explore. It includes familiar objects such as the Eagle (Sh2-49), Heart (Sh2-190), and Orion (Sh2-281) Nebulas. Despite the catalog's name, it contains more than the glow of ionized hydrogen that defines H II regions: it also includes planetary nebulas, such as the Medusa Nebula (Sh2-274), and supernova remnants, such as the Spaghetti Nebula (Sh2-240).

Astrophotographer Bing Xin captured the objects from the dark skies of Eastern China and Inner Mongolia. He used narrowband filters that primarily capture light from ionized hydrogen and oxygen, along with red-green-blue filters. Each object required 2 to 6 hours of exposure, and completing the entire catalog took around 800 hours.

The APOD asks viewers which object is their favorite. It also notes that APOD's email for image submissions has changed, directs readers to APOD Submissions, and says tomorrow's picture is 'just Curiosity.' The image is dated October 2, 2026, credited to Bing Xin, with authors and editors Keighley Rockcliffe, Robert Nemiroff, Jerry Bonnell, and Cecilia Chirenti; it is a service of ASD at NASA/GSFC, NASA Science Activation, and Michigan Tech. U.