HD 18438 planetary system
HD 18438 is a cool red dwarf of spectral type M2.5 III approximately 731 light-years from Earth (224.15 parsecs). It hosts 1 confirmed exoplanet.
Host star
- Name
- HD 18438
- Spectral type
- M2.5 III
- Effective temperature
- 3,860 K
- Mass
- 1.84 M☉ (solar masses)
- Radius
- 88.47 R☉ (solar radii)
- Distance
- 224.15 pc (731 ly)
- Hipparcos catalog
- HIP 14417
Confirmed planets (1)
| Planet | Class | Mass (M⊕) | Radius (R⊕) | Period (d) | Distance (AU) | Eq. temp (K) | Discovered |
|---|---|---|---|---|---|---|---|
| HD 18438 b | Neptune-like | 6674.40 | 12.10 | 803.00 | 2.1000 | — | 2023 |
The planets in detail
HD 18438 b is a Neptune-like world with about 12.10 Earth radii and 6674.40 Earth masses. It orbits HD 18438 at 2.1000 AU with a 2.2-Earth-year orbit, and no published equilibrium temperature. It was confirmed in 2023 via radial velocity (Doppler) measurements.
Discovery
The single planet in the HD 18438 system was confirmed in 2023 using radial velocity (Doppler) measurements. Detection facilities: Bohyunsan Optical Astronomical Observatory.
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 46.5318°, declination 79.4186°. 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.
