# Messier 18

> Open cluster

**Wikidata**: [Q11370](https://www.wikidata.org/wiki/Q11370)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Messier_18)  
**Source**: https://4ort.xyz/entity/messier-18


## References

1. SIMBAD
2. VizieR
3. On Structural Properties of Open Galactic Clusters and their Spatial Distribution. Catalog of Open Galactic Clusters
4. [Messier 18](http://messier.seds.org/m/m018.html)
5. Freebase Data Dumps. 2013
6. A RAVE investigation on Galactic open clusters
7. Astrophysical parameters of Galactic open clusters
8. The orbits of open clusters in the Galaxy
9. Proper motions of the optically visible open clusters based on the UCAC4 catalog