Cebalrai
HR 6603 · HIP 86742 · β Oph
👁️ Naked-eye
📋 A written introduction is coming — for now this page shows official values only.
Star
- Apparent magnitude
- 2.75 mag
- Parallax
- 39.85 mas → about 81.8 light-years away
- Spectral type
- K2III
- Right ascension
- 265.8681°
- Declination
- 4.5673°
- Designation
- HR 6603
- Bayer designation
- β Oph
- HIP number
- 86742
- IAU name adopted
- 2016-08-21
- Name language
- Arabic
- Name origin (IAU)
- Applied in recent times from its pre-Islamic Arabian name kalb al-ra'i, "the Shepherd's Dog" (in other traditions α Her and 28/29 Cep are given the same name). This dog, together with the shepherd (marked by α Oph), and the two lines of stars enclosing the Pasture, and all the dim stellar sheep in that portion of the sky (al-ghanam or al-aghnam for the sheep), seem to form a complete group of pre-Islamic Arabian figures.
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 82 years to reach Earth — the light you see tonight left around AD 1944 (official distance ÷ speed of light).
- At magnitude 2.8 it is bright enough for the naked eye (limit about 6) — look from somewhere dark.
- Declination 4.6° — 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.