| Identification Data |
| Common Name | Rasalhague |
| Constellation | Ophiuchus |
| Star Name | 55alp Oph |
| Skymap Number | 17340172 |
| Henry Draper (HD) Number | 159561 |
| Harvard Revised (HR) Number | 6556 |
| SAO Number | 102932 |
| Durchmusterung (DM) Number | BD+12 3252 |
Washington Double Stars (WDS) Number
|
|
| Positional Data |
| Position and Proper Motion (PPM) Number | 133563 |
| Right Ascension (RA) J2000 | 17h 34m 56.070s |
| Declination (Dec) J2000 | +12° 33' 36.125" |
| Position Uncertainty | 0.0119s |
| Proper Motion in RA (J2000)/cos(Dec) | +0.00752 |
| Proper Motion in Dec (J2000) | -0.222666 |
| Radial Velocity | +012.6km s-1 |
| Trigonometric Parallax | +0.06984s |
| Trigonometric Parallax Uncertainty | 0.00088s |
| GCI Unit Vector in X (J2000) | -0.106539 |
| GCI Unit Vector in Y (J2000) | -0.970237 |
| GCI Unit Vector in Z (J2000) | 0.217462 |
| Galactic Longitude | 35.90° |
Galactic Latitude
| 22.57°
|
| Observational Data |
| Observed Visual Magnitude (V) | 2.09 |
| Derived Visual Magnitude | |
| Derived Visual Magnitude or Observed Visual Magnitude Uncertainty | 0.003 |
| Observed B Magnitude | 2.28 |
| Observed B-V Colour | +0.190 |
| Observed B Magnitude or (B-V) Magnitude Uncertainty | 0.004 |
| Observed U Magnitude | |
| Observed U-B Colour | |
| Observed U Magnitude or (U-B) Magnitude Uncertainty | |
| Observed Photovisual Magnitude | 2.1 |
| Observed Photographic Magnitude | |
| Morgan Keenan (MK) Spectral Type | A5III |
| One-Dimensional Spectral Class | A5 |
| Position Angle | |
| Year of Observation | AD |
