| Identification Data |
| Common Name | |
| Constellation | Canis Major |
| Star Name | 30tau CMa |
| Skymap Number | 7180189 |
| Henry Draper (HD) Number | 57061 |
| Harvard Revised (HR) Number | 2782 |
| SAO Number | 173446 |
| Durchmusterung (DM) Number | CD-24 5176 |
Washington Double Stars (WDS) Number
| 07187-2457
|
| Positional Data |
| Position and Proper Motion (PPM) Number | 252114 |
| Right Ascension (RA) J2000 | 7h 18m 42.480s |
| Declination (Dec) J2000 | -24° 57' 15.707" |
| Position Uncertainty | 0.0086s |
| Proper Motion in RA (J2000)/cos(Dec) | -0.00013 |
| Proper Motion in Dec (J2000) | +0.003767 |
| Radial Velocity | +040.4km s-1 |
| Trigonometric Parallax | +0.00102s |
| Trigonometric Parallax Uncertainty | 0.00071s |
| GCI Unit Vector in X (J2000) | -0.305283 |
| GCI Unit Vector in Y (J2000) | 0.853701 |
| GCI Unit Vector in Z (J2000) | -0.421896 |
| Galactic Longitude | 238.19° |
Galactic Latitude
| -5.54°
|
| Observational Data |
| Observed Visual Magnitude (V) | 4.40 |
| Derived Visual Magnitude | |
| Derived Visual Magnitude or Observed Visual Magnitude Uncertainty | 0.002 |
| Observed B Magnitude | 4.23 |
| Observed B-V Colour | -0.166 |
| 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 | O9Ib |
| One-Dimensional Spectral Class | Oe5 |
| Position Angle | 75 |
| Year of Observation | 1960. AD |
