Star · G2V
GJ 4021B
GJ 4021B is a main-sequence star of spectral type G2V in the constellation Draco, 79.6 light-years from the Sun.
| Constellation | Draco |
|---|---|
| Distance | 79.6 light-years (24.4 pc) |
| Apparent magnitude | magnitude 14.70 |
| Absolute magnitude | magnitude 12.76 |
| Spectral type | G2V |
| Surface temperature | 5,780 K |
| Luminosity | 7.28 × 10⁻⁴ L☉ |
| Radius | 0.0269 R☉ |
| Mass | 0.0819 M☉ (estimated) |
| Right ascension (J2000) | 17h 38m 40.2s |
| Declination (J2000) | +61° 14′ 03″ |
| Space velocity (relative to the Sun) | 6.9 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 14.70. Visible from the whole Northern Hemisphere and south to latitude 29° S. North of latitude 29° 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 1946. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.4 million years.
The Sun seen from there
From a planet around GJ 4021B, the Sun would look like a star of magnitude 6.77, in the direction where our sky has the constellation Dorado. It would be invisible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- WISE J173623.03+605920.2 4.56 light-years
- WISEPA J171717.02+612859.3 6.23 light-years
- WISEPA J172844.93+571643.6 6.74 light-years
- GJ 9582B 6.84 light-years
- GJ 9582A 6.86 light-years
- WISE J173859.27+614242.1 7.17 light-years
- 36 Dra 8.00 light-years
- GJ 4037 10.00 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.