# Q66639275

> astrophysical X-ray source in the constellation Hydra

**Wikidata**: [Q66639275](https://www.wikidata.org/wiki/Q66639275)  
**Source**: https://4ort.xyz/entity/q66639275


## References

1. SIMBAD
2. Source
3. The Tycho-2 catalogue of the 2.5 million brightest stars
4. Gaia Data Release 2
5. VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
6. Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system
7. The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ∼14 000 F and G dwarfs
8. ROSAT All-Sky Survey Faint Source Catalogue
9. New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s)