# 21 Leonis

> star in the constellation Leo

**Wikidata**: [Q66481592](https://www.wikidata.org/wiki/Q66481592)  
**Source**: https://4ort.xyz/entity/21-leonis


## References

1. SIMBAD
2. VizieR Online Data Catalog: Henry Draper Catalogue and Extension, published in Ann. Harvard Obs. 91-100 (1918-1925)
3. The Tycho-2 catalogue of the 2.5 million brightest stars
4. VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
5. Gaia Early Data Release 3
6. Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
7. Gaia Data Release 2