Alhena
HR 2421 · HIP 31681 · γ Gem
👁️ Naked-eye
📋 A written introduction is coming — for now this page shows official values only.
Star
- Apparent magnitude
- 1.92 mag
- Parallax
- 29.84 mas → about 109.3 light-years away
- Spectral type
- A0IV
- Right ascension
- 99.428°
- Declination
- 16.3993°
- Designation
- HR 2421
- Bayer designation
- γ Gem
- HIP number
- 31681
- IAU name adopted
- 2016-07-20
- Name language
- Arabic
- Name origin (IAU)
- Applied in recent times from the pre-Islamic Arabian lunar mansion name al-bana, possibly meaning "the Mark on the Neck of a Camel," for γ and ξ Gem, or alternatively for γ, ξ, η, μ, and v Gem.
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 109 years to reach Earth — the light you see tonight left around AD 1917 (official distance ÷ speed of light).
- At magnitude 1.9 it is bright enough for the naked eye (limit about 6) — look from somewhere dark.
- Declination 16.4° — 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.