Gomeisa
HR 2845 · HIP 36188 · β CMi
👁️ Naked-eye
📋 A written introduction is coming — for now this page shows official values only.
Star
- Apparent magnitude
- 2.89 mag
- Parallax
- 20.17 mas → about 161.7 light-years away
- Spectral type
- B8Vvar
- Right ascension
- 111.7877°
- Declination
- 8.2893°
- Designation
- HR 2845
- Bayer designation
- β CMi
- HIP number
- 36188
- IAU name adopted
- 2016-07-20
- Name language
- Arabic
- Name origin (IAU)
- From the pre-Islamic Arabian surname al-ghumaisa', "the Little Bleary-eyed One ('with a filthy fluid in the corner of the eye')," for α CMi. Wrongly transferred to β CMi in recent times. The original significance of the surname is unknown. Perhaps as an attempt to explain the significance of al-ghumaisa', as well as that of the surname al-<abur, "the One Having Crossed Over [a river, etc.]," for α CMa, an Arabic fable developed associating these and other equally enigmatic star names. According to one version of the fable, al-ghumaisa and ai-'abur were sisters, and their brother was suhail (α Car). Suhail, in turn, was the suitor of al-jauza' (the feminine pre-Islamic Arabian figure in place of Orion). In coitus, suhail broke the spine of al-jauza', thus killing her, after which suhail fled south. He was followed by his sister al-'abur who "crossed over" the Milky Way (where the two stars now lie in the southern sky). Meanwhile suhail's second sister, al-ghumaisa, was left alone north of the Milky Way, weeping, until her "eyes became bleary." (The pre-Islamic Arabian name for α CMa was al-shi'ra, of unknown meaning. Apparently it was developed into a dualis form, al-shi'rayan, to accomodate both α CMa and α CMi, with the aforementioned "surnames" distinguishing the two.)
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 162 years to reach Earth — the light you see tonight left around AD 1864 (official distance ÷ speed of light).
- At magnitude 2.9 it is bright enough for the naked eye (limit about 6) — look from somewhere dark.
- Declination 8.3° — 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.