Star · M3
Gl 817
Gl 817 is a main-sequence star of spectral type M3 in the constellation Capricornus, 59.7 light-years from the Sun.
| Other names | HIP 104059 |
|---|---|
| Constellation | Capricornus |
| Distance | 59.7 light-years (18.3 pc) |
| Apparent magnitude | magnitude 11.45 |
| Absolute magnitude | magnitude 10.14 |
| Spectral type | M3 |
| Surface temperature | 3,880 K |
| Luminosity | 0.0248 L☉ |
| Radius | 0.348 R☉ |
| Mass | 0.38 M☉ (estimated) |
| Right ascension (J2000) | 21h 04m 53.4s |
| Declination (J2000) | −16° 57′ 32″ |
| Space velocity (relative to the Sun) | 194.4 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 11.45. Visible from the whole Southern Hemisphere and north to latitude 73° N. South of latitude 73° S 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 the year 1966. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.1 million years.
The Sun seen from there
From a planet around Gl 817, the Sun would look like a star of magnitude 6.14, in the direction where our sky has the constellation Cancer. It would be visible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- Gl 819A 4.35 light-years
- Gl 819B 4.40 light-years
- WISEA J211456.86-180519.0 5.03 light-years
- CWISE J205701.64-170407.3 5.88 light-years
- Gl 800B 6.43 light-years
- Gl 800A 6.43 light-years
- 2MASSI J2104149-103736 7.29 light-years
- Gl 830 7.95 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.