Star · M3
Gl 257B
Gl 257B is a supergiant star of spectral type M3 in the constellation Puppis, 26.2 light-years from the Sun.
| Constellation | Puppis |
|---|---|
| Distance | 26.2 light-years (8.04 pc) |
| Apparent magnitude | magnitude 11.70 |
| Absolute magnitude | magnitude 12.17 |
| Spectral type | M3 |
| Surface temperature | 2,980 K |
| Luminosity | 0.0212 L☉ |
| Radius | 0.548 R☉ |
| Mass | 1.2 M☉ (estimated) |
| Right ascension (J2000) | 6h 57m 47.4s |
| Declination (J2000) | −44° 17′ 27″ |
| Space velocity (relative to the Sun) | 44.9 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 11.70. Visible from the whole Southern Hemisphere and north to latitude 46° N. South of latitude 46° S it never sets. It stands highest at midnight in January, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 2000. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 465 thousand years.
The Sun seen from there
From a planet around Gl 257B, the Sun would look like a star of magnitude 4.36, in the direction where our sky has the constellation Lyra. It would be visible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- Gl 257A 0.04 light-years
- 2MASS J07290002-3954043 3.32 light-years
- WISE J071322.55-291751.9 8.16 light-years
- Gl 318 10.9 light-years
- GJ 1088 11.2 light-years
- Gl 293 11.3 light-years
- WISE J064723.23-623235.5 11.4 light-years
- WISEPC J075946.98-490454.0 11.6 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.