# Ring Nebula

> planetary nebula in the constellation Lyra

**Wikidata**: [Q13969](https://www.wikidata.org/wiki/Q13969)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Ring_Nebula)  
**Source**: https://4ort.xyz/entity/ring-nebula


## References

1. SIMBAD
2. VizieR
3. [Messier 57](http://www.messier.seds.org/m/m057.html)
4. Spectroscopic investigation of old planetaries. III. Spectral types, magnitudes, and distances
5. Freebase Data Dumps. 2013
6. The binary fraction of planetary nebula central stars – I. A high-precision, I-band excess search
7. Gaia Data Release 2
8. Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Radial velocities: The Wilson-Evans-Batten catalogue