| Identification Data |
| Common Name | Shedir |
| Constellation | Cassiopeia |
| Star Name | 18alp Cas |
| Skymap Number | 400067 |
| Henry Draper (HD) Number | 3712 |
| Harvard Revised (HR) Number | 168 |
| SAO Number | 21609 |
| Durchmusterung (DM) Number | BD+55 139 |
Washington Double Stars (WDS) Number
| 00405+5632
|
| Positional Data |
| Position and Proper Motion (PPM) Number | 25578 |
| Right Ascension (RA) J2000 | 0h 40m 30.440s |
| Declination (Dec) J2000 | +56° 32' 14.392" |
| Position Uncertainty | 0.0046s |
| Proper Motion in RA (J2000)/cos(Dec) | +0.00609 |
| Proper Motion in Dec (J2000) | -0.032266 |
| Radial Velocity | -003.9km s-1 |
| Trigonometric Parallax | +0.01427s |
| Trigonometric Parallax Uncertainty | 0.00057s |
| GCI Unit Vector in X (J2000) | 0.542803 |
| GCI Unit Vector in Y (J2000) | 0.096950 |
| GCI Unit Vector in Z (J2000) | 0.834245 |
| Galactic Longitude | 121.42° |
Galactic Latitude
| -6.30°
|
| Observational Data |
| Observed Visual Magnitude (V) | 2.25 |
| Derived Visual Magnitude | |
| Derived Visual Magnitude or Observed Visual Magnitude Uncertainty | 0.002 |
| Observed B Magnitude | 3.43 |
| Observed B-V Colour | +1.175 |
| Observed B Magnitude or (B-V) Magnitude Uncertainty | 0.002 |
| Observed U Magnitude | |
| Observed U-B Colour | |
| Observed U Magnitude or (U-B) Magnitude Uncertainty | |
| Observed Photovisual Magnitude | 2.5 |
| Observed Photographic Magnitude | |
| Morgan Keenan (MK) Spectral Type | K0-IIIa |
| One-Dimensional Spectral Class | K0 |
| Position Angle | 275 |
| Year of Observation | 1934. AD |
