Star · O6
λ Cep
λ Cep is a supergiant star of spectral type O6 in the constellation Cepheus, 2,773 light-years from the Sun.
| Other names | HIP 109556 |
|---|---|
| Constellation | Cepheus |
| Distance | 2,773 light-years (850.3 pc) |
| Apparent magnitude | magnitude 5.05 |
| Absolute magnitude | magnitude −4.60 |
| Spectral type | O6 |
| Surface temperature | 8,230 K |
| Luminosity | 6,380 L☉ |
| Radius | 39.3 R☉ |
| Mass | 11.1 M☉ (estimated) |
| Right ascension (J2000) | 22h 11m 30.6s |
| Declination (J2000) | +59° 24′ 52″ |
| Space velocity (relative to the Sun) | 90.4 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.05). Visible from the whole Northern Hemisphere and south to latitude 31° S. North of latitude 31° N it never sets. It stands highest at midnight in August, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around 748 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 49 million years.
The Sun seen from there
From a planet around λ Cep, the Sun would look like a star of magnitude 14.48, in the direction where our sky has the constellation Carina. 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.