Star · M1
Gl 642
Gl 642 is a main-sequence star of spectral type M1 in the constellation Ophiuchus, 65.5 light-years from the Sun.
| Other names | HIP 82694 |
|---|---|
| Constellation | Ophiuchus |
| Distance | 65.5 light-years (20.1 pc) |
| Apparent magnitude | magnitude 10.75 |
| Absolute magnitude | magnitude 9.24 |
| Spectral type | M1 |
| Surface temperature | 3,940 K |
| Luminosity | 0.0528 L☉ |
| Radius | 0.493 R☉ |
| Mass | 0.479 M☉ (estimated) |
| Right ascension (J2000) | 16h 54m 12.1s |
| Declination (J2000) | +11° 54′ 53″ |
| Space velocity (relative to the Sun) | 89.4 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 10.75. Visible from the whole Northern Hemisphere and south to latitude 78° S. North of latitude 78° N it never sets. It stands highest at midnight in June, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1961. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.2 million years.
The Sun seen from there
From a planet around Gl 642, the Sun would look like a star of magnitude 6.34, in the direction where our sky has the constellation Eridanus. It would be visible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- GJ 3984 4.87 light-years
- GJ 3990 6.88 light-years
- WISE J172134.46+111739.4 7.69 light-years
- GJ 1203 7.73 light-years
- GJ 3998 8.55 light-years
- HIP 84195 9.40 light-years
- SDSS J163022.92+081822.0 10.3 light-years
- Gl 627B 10.3 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.