Star · G8V
Kepler-397
Kepler-397 is a main-sequence star of spectral type G8V in the constellation Cygnus, 3,160 light-years from the Sun. It is orbited by 2 confirmed exoplanet(s).
| Constellation | Cygnus |
|---|---|
| Distance | 3,160 light-years (969.0 pc) |
| Apparent magnitude | magnitude 16.36 |
| Absolute magnitude | magnitude 6.43 |
| Spectral type | G8V |
| Surface temperature | 5,310 K |
| Luminosity | 0.421 L☉ |
| Radius | 0.767 R☉ |
| Mass | 0.844 M☉ |
| Age | 5.3 billion years |
| Metallicity [Fe/H] | -0.24 |
| Right ascension (J2000) | 19h 43m 34.6s |
| Declination (J2000) | +42° 22′ 50″ |
| Space velocity (relative to the Sun) | 23.7 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 16.36. Visible from the whole Northern Hemisphere and south to latitude 48° S. North of latitude 48° 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 1135 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 56 million years.
The Sun seen from there
From a planet around Kepler-397, the Sun would look like a star of magnitude 14.76, in the direction where our sky has the constellation Puppis. It would be invisible to the naked eye.
Planets
- Kepler-397 b 22.3-day orbit · 2.46 R⊕
- Kepler-397 c 135-day orbit · 6.18 R⊕
Stellar parameters from the NASA Exoplanet Archive; position and brightness from the HYG / AT-HYG catalogue.