Star · B3V
40 Tau
40 Tau is a main-sequence star of spectral type B3V in the constellation Taurus, 722.2 light-years from the Sun.
| Other names | HIP 18957 |
|---|---|
| Constellation | Taurus |
| Distance | 722.2 light-years (221.4 pc) |
| Apparent magnitude | magnitude 5.32 |
| Absolute magnitude | magnitude −1.41 |
| Spectral type | B3V |
| Surface temperature | 11,250 K |
| Luminosity | 526 L☉ |
| Radius | 6.04 R☉ |
| Mass | 5.44 M☉ (estimated) |
| Right ascension (J2000) | 4h 03m 44.6s |
| Declination (J2000) | +5° 26′ 08″ |
| Space velocity (relative to the Sun) | 13.5 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.32). Visible from the whole Northern Hemisphere and south to latitude 85° S. It stands highest at midnight in November, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1304. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 13 million years.
The Sun seen from there
From a planet around 40 Tau, the Sun would look like a star of magnitude 11.56, in the direction where our sky has the constellation Ophiuchus. It would be invisible to the naked eye.
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.