NGC 6590

NGC 6590 is commonly listed as a small reflection nebula in Sagittarius, although catalog cross-identifications around NGC 6590 and NGC 6595 can make descriptions inconsistent. It is often shown near the reflection nebula NGC 6589 and the red emission nebula IC 1284.

Many deep-sky catalogues cross-identify NGC 6590 with NGC 6595 and also give names such as IC 4700 or LBN 43 for the same region. If you are checking a star chart, use the coordinates as well as the catalog number because NGC 6589 is a different nearby reflection nebula.

Some observing catalogues list its apparent size at roughly 4 by 3 arcminutes and its brightness near magnitude 7, but the nebula is diffuse. A dark sky and a telescope in the 6 to 8 inch range can make the surrounding haze easier to detect than a bright city sky.

The history is not clean because older observations were assigned different catalogue numbers. Current cross-identification notes connect John Herschel's 1830 observation, Lewis Swift's 1885 observation, and later NGC and IC entries, so attributing NGC 6590 simply to Truman Safford in 1883 can be misleading.