| Identification Data |
| Common Name | Yildun |
| Constellation | Ursa Minor |
| Star Name | 23del UMi |
| Skymap Number | 17320068 |
| Henry Draper (HD) Number | 166205 |
| Harvard Revised (HR) Number | 6789 |
| SAO Number | 2937 |
| Durchmusterung (DM) Number | BD+86 269 |
Washington Double Stars (WDS) Number
|
|
| Positional Data |
| Position and Proper Motion (PPM) Number | 3067 |
| Right Ascension (RA) J2000 | 17h 32m 13.000s |
| Declination (Dec) J2000 | +86° 35' 11.258" |
| Position Uncertainty | 0.0060s |
| Proper Motion in RA (J2000)/cos(Dec) | +0.01180 |
| Proper Motion in Dec (J2000) | +0.054066 |
| Radial Velocity | -007.6km s-1 |
| Trigonometric Parallax | +0.01785s |
| Trigonometric Parallax Uncertainty | 0.00048s |
| GCI Unit Vector in X (J2000) | -0.007201 |
| GCI Unit Vector in Y (J2000) | -0.059105 |
| GCI Unit Vector in Z (J2000) | 0.998226 |
| Galactic Longitude | 119.29° |
Galactic Latitude
| 28.24°
|
| Observational Data |
| Observed Visual Magnitude (V) | 4.35 |
| Derived Visual Magnitude | |
| Derived Visual Magnitude or Observed Visual Magnitude Uncertainty | 0.002 |
| Observed B Magnitude | 4.38 |
| Observed B-V Colour | +0.032 |
| 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 | 4.4 |
| Observed Photographic Magnitude | |
| Morgan Keenan (MK) Spectral Type | A1Vn |
| One-Dimensional Spectral Class | A0 |
| Position Angle | |
| Year of Observation | AD |