Star · K2I
47 Cyg
47 Cyg is a supergiant star of spectral type K2I in the constellation Cygnus, 3,710 light-years from the Sun.
| Other names | HIP 101474 |
|---|---|
| Constellation | Cygnus |
| Distance | 3,710 light-years (1,137 pc) |
| Apparent magnitude | magnitude 4.61 |
| Absolute magnitude | magnitude −5.67 |
| Spectral type | K2I |
| Surface temperature | 3,660 K |
| Luminosity | 70,500 L☉ |
| Radius | 661 R☉ |
| Mass | 2.2 M☉ (estimated) |
| Right ascension (J2000) | 20h 33m 54.2s |
| Declination (J2000) | +35° 15′ 03″ |
| Space velocity (relative to the Sun) | 30.1 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 4.61). Visible from the whole Northern Hemisphere and south to latitude 55° S. North of latitude 55° N it never sets. It stands highest at midnight in July, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around 1685 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 66 million years.
The Sun seen from there
From a planet around 47 Cyg, the Sun would look like a star of magnitude 15.11, in the direction where our sky has the constellation Pyxis. 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.