# DH Hydrae

> RR Lyrae variable star in the constellation Hydra

**Wikidata**: [Q88987173](https://www.wikidata.org/wiki/Q88987173)  
**Source**: https://4ort.xyz/entity/dh-hydrae


## References

1. SIMBAD
2. Observations of Southern RR Lyr stars
3. Gaia Data Release 3
4. Probing the outer galactic halo with RR Lyrae from the Catalina surveys
5. General Catalogue of Variable Stars, 3rd ed.
6. Gaia Data Release 2
7. VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
8. Broadband UBVRCIC Photometry of Horizontal‐Branch and Metal‐poor Candidates from the HK and Hamburg/ESO Surveys. I
9. The Tycho-2 catalogue of the 2.5 million brightest stars
10. Gaia Early Data Release 3
11. On the Use of Field RR Lyrae as Galactic Probes. III. The α-element Abundances
12. On the Use of Field RR Lyrae as Galactic Probes. II. A New ΔS Calibration to Estimate Their Metallicity