alf Tau planetary system
alf Tau is an orange main-sequence star of spectral type K5 III approximately 66.6 light-years from Earth (20.43 parsecs). It hosts 1 confirmed exoplanet.
Host star
- Name
- alf Tau
- Spectral type
- K5 III
- Effective temperature
- 4,055 K
- Mass
- 1.13 M☉ (solar masses)
- Radius
- 45.10 R☉ (solar radii)
- Distance
- 20.43 pc (66.6 ly)
- Hipparcos catalog
- HIP 21421
Confirmed planets (1)
| Planet | Class | Mass (M⊕) | Radius (R⊕) | Period (d) | Distance (AU) | Eq. temp (K) | Discovered |
|---|---|---|---|---|---|---|---|
| alf Tau b | Neptune-like | 2056.36 | 12.70 | 628.96 | 1.4600 | — | 2015 |
The planets in detail
alf Tau b is a Neptune-like world with about 12.70 Earth radii and 2056.36 Earth masses. It orbits alf Tau at 1.4600 AU with a 629-day year, and no published equilibrium temperature. It was confirmed in 2015 via radial velocity (Doppler) measurements.
Discovery
The single planet in the alf Tau system was confirmed in 2015 using radial velocity (Doppler) measurements. Detection facilities: Multiple Observatories.
Observing from Earth
Exoplanets cannot be resolved visually with amateur telescopes — the host star's glare is overwhelming and even space-based direct imaging requires sophisticated coronagraphs. What you can observe is the host star itself at right ascension 68.9802°, declination 16.5092°. Use the 3D orrery above to inspect orbital geometry, planetary scale, and the habitable-zone overlay — the orbits are computed from the published Keplerian elements and animate at user-controlled time rates.
