Rasalhague
HR 6556 · HIP 86032 · α Oph
👁️ Naked-eye
📋 A written introduction is coming — for now this page shows official values only.
Star
- Apparent magnitude
- 2.07 mag
- Parallax
- 67.13 mas → about 48.6 light-years away
- Spectral type
- A5III
- Right ascension
- 263.7336°
- Declination
- 12.56°
- Designation
- HR 6556
- Bayer designation
- α Oph
- HIP number
- 86032
- IAU name adopted
- 2016-07-20
- Name language
- Arabic
- Name origin (IAU)
- Applied with various spellings since medieval times, from its name for the Arabic Almagest period ra's al-ḥawwa', "the Head of the Serpent Collector."
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 49 years to reach Earth — the light you see tonight left around AD 1977 (official distance ÷ speed of light).
- At magnitude 2.1 it is bright enough for the naked eye (limit about 6) — look from somewhere dark.
- Declination 12.6° — 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.