NGC 6559 is a star-forming region located at a distance of about 5000 light-years from Earth, in the constellation of Sagittarius, showing both emission (red) and reflection (bluish) regions. NGC 6559 is relatively small at only a few lightyears across. The nebula is found within Sharpless 29, an irregular H II region.
References
External links Media related to NGC 6559 at Wikimedia Commons NASA Astronomy Picture of the Day: Three Nebular in Narrow Band (2 November 2007) — one of the three nebulae shown was NGC 6559 NASA Astronomy Picture of the Day: Stars, Dust and Nebula in NGC 6559 (2 August 2009) NGC 6559 Archived 2015-07-16 at the Wayback Machine