Star · G2I
GJ 3107
GJ 3107 is a supergiant star of spectral type G2I in the constellation Cetus, 20,000 light-years from the Sun.
| Other names | HIP 7993 |
|---|---|
| Constellation | Cetus |
| Distance | 20,000 light-years (6,146 pc) |
| Apparent magnitude | magnitude 11.93 |
| Absolute magnitude | magnitude −2.01 |
| Spectral type | G2I |
| Surface temperature | 5,780 K |
| Luminosity | 593 L☉ |
| Radius | 24.3 R☉ |
| Mass | 5.63 M☉ (estimated) |
| Right ascension (J2000) | 1h 42m 39.1s |
| Declination (J2000) | −24° 37′ 40″ |
| Space velocity (relative to the Sun) | 167.0 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 11.93. Visible from the whole Southern Hemisphere and north to latitude 65° N. South of latitude 65° S it never sets. It stands highest at midnight in October, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 20 thousand years ago. At that time Homo sapiens was spreading out of Africa; there was no farming yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 356 million years.
The Sun seen from there
From a planet around GJ 3107, the Sun would look like a star of magnitude 18.77, in the direction where our sky has the constellation Boötes. 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.