NGC 6520
Open cluster in the constellation Sagittarius
title: "NGC 6520" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["open-clusters", "sagittarius-(constellation)", "ngc-objects"] description: "Open cluster in the constellation Sagittarius" topic_path: "general/open-clusters" source: "https://en.wikipedia.org/wiki/NGC_6520" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary Open cluster in the constellation Sagittarius ::
::data[format=table title="Infobox open cluster"]
| Field | Value |
|---|---|
| name | NGC 6520 |
| image | [[File:The Starry Dandelion and the Cosmic Gecko NGC 6520 (gemini-20070806-ngc6520gem-clnflattrim).tiff |
| caption | NGC 6520 and dark nebula Barnard 86 |
| credit | |
| epoch | J2000 |
| constellation | Sagittarius |
| ra | |
| dec | |
| dist_ly | 1605.0 pc |
| appmag_v | 7.6 |
| size_v | |
| radius_ly | |
| mass_msol | |
| age | 178 Myr |
| notes | |
| names | Cr 361, Mel 187 |
| :: |
| name = NGC 6520 | image = [[File:The Starry Dandelion and the Cosmic Gecko NGC 6520 (gemini-20070806-ngc6520gem-clnflattrim).tiff|300px]] | caption = NGC 6520 and dark nebula Barnard 86 | credit = | epoch = J2000 | constellation = Sagittarius | ra = | dec = | dist_ly = 1605.0 pc | dist_pc = | appmag_v = 7.6 | size_v = | radius_ly = | mass_msol = | age = 178 Myr | notes = | names = Cr 361, Mel 187
NGC 6520 is an open cluster of stars in the southern constellation of Sagittarius, about 4° to the east of the Galactic Center. With an apparent visual magnitude of 7.6 and an angular size of , it can be viewed with binoculars or a small telescope. Just to the west of this cluster is the dark nebula Barnard 86, dubbed the Ink Spot. Both features are viewed against the dense stary background of the Large Sagittarius Star Cloud. This cluster is located at a distance of approximately 1605.0 pc from the Sun.
This is a young open cluster of stars with age estimates yielding a values of million years. However, the presence of stars with a spectral class of B4 and B5 suggest a much younger age of 60 million years. The estimated mass of this cluster is . The cluster and the nearby dark nebula Barnard 86 have radial velocities that differ by , and hence may be unrelated.
Two type 2 chemically peculiar stars and two Lambda Bootis candidates have been found among the members. Polarization measurements of the cluster members suggests that there are three closer dust layers partially obscuring the view from the perspective of the Earth.
Gallery
File:NGC 6520 and Barnard 86.jpg|Star cluster NGC 6520 and dark nebula Barnard 86 within the Large Sagittarius Star Cloud File:NGC 6520 map.png|Map showing the location of NGC 6520 File:NGC 6520 (noao-n6520calvert).jpg|Kitt Peak image
References
::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::