Star · M2.5 III
HD 18438
HD 18438 is a subgiant star of spectral type M2.5 III in the constellation Cepheus, 768.0 light-years from the Sun. It is orbited by 1 confirmed exoplanet(s).
| Other names | HIP 14417 |
|---|---|
| Constellation | Cepheus |
| Distance | 768.0 light-years (235.5 pc) |
| Apparent magnitude | magnitude 5.49 |
| Absolute magnitude | magnitude −1.37 |
| Spectral type | M2.5 III |
| Surface temperature | 3,860 K |
| Luminosity | 929 L☉ |
| Radius | 88.5 R☉ |
| Mass | 1.84 M☉ |
| Age | 5.5 billion years |
| Metallicity [Fe/H] | -0.40 |
| Right ascension (J2000) | 3h 06m 07.8s |
| Declination (J2000) | +79° 25′ 07″ |
| Space velocity (relative to the Sun) | 57.6 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.49). Visible from the whole Northern Hemisphere and south to latitude 11° S. North of latitude 11° N it never sets.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1258. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 14 million years.
The Sun seen from there
From a planet around HD 18438, the Sun would look like a star of magnitude 11.69, in the direction where our sky has the constellation Apus. It would be invisible to the naked eye.
Planets
- HD 18438 b 803-day orbit · 12.1 R⊕
Stellar parameters from the NASA Exoplanet Archive; position and brightness from the HYG / AT-HYG catalogue.