Jishui
HR 2930 · HIP 37265 · ο Gem
👁️ Naked-eye
📋 A written introduction is coming — for now this page shows official values only.
Star
- Apparent magnitude
- 4.9 mag
- Parallax
- 19.61 mas → about 166.3 light-years away
- Spectral type
- F3III
- Right ascension
- 114.7914°
- Declination
- 34.5843°
- Designation
- HR 2930
- Bayer designation
- ο Gem
- HIP number
- 37265
- IAU name adopted
- 2019-12-17
- Name language
- Chinese
- Name origin (IAU)
- traditional Chinese single star asterism: translations of the term are "Bilgewater", "a store of water to make wine", or "accumulated water (held in by dikes for future use)". It refers to a faint star in Gemini or Perseus that is idenfied differently by modern authors. Sun and Kistemaker (1997) from Han sources and Sun Shuwei (Stellarium) from a medieval source both suggest o Gem while Xu et al. (2000) identify lambda Persei.
Source:IAU Working Group on Star Names · checked 2026-11-02 ↗ESA Hipparcos Catalogue (ESA Gaia Archive) · checked 2026-11-03 ↗
Related
Constellation
In everyday life
- Light from this object takes about 166 years to reach Earth — the light you see tonight left around AD 1860 (official distance ÷ speed of light).
- At magnitude 4.9 it is bright enough for the naked eye (limit about 6) — look from somewhere dark.
- Declination 34.6° — it rises above the horizon in Seoul (37.6° N), so it is visible from Korea in the right season.
Worked out from this object's official values.