Star · M1
GJ 9721A
GJ 9721A is a main-sequence star of spectral type M1 in the constellation Aquarius, 93.6 light-years from the Sun.
| Other names | HIP 104383 |
|---|---|
| Constellation | Aquarius |
| Distance | 93.6 light-years (28.7 pc) |
| Apparent magnitude | magnitude 9.45 |
| Absolute magnitude | magnitude 7.16 |
| Spectral type | M1 |
| Surface temperature | 4,410 K |
| Luminosity | 0.229 L☉ |
| Radius | 0.819 R☉ |
| Mass | 0.691 M☉ (estimated) |
| Right ascension (J2000) | 21h 08m 45.5s |
| Declination (J2000) | −4° 25′ 37″ |
| Space velocity (relative to the Sun) | 11.9 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 9.45. Visible from the whole Southern Hemisphere and north to latitude 86° N. 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 1932. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.7 million years.
The Sun seen from there
From a planet around GJ 9721A, the Sun would look like a star of magnitude 7.12, in the direction where our sky has the constellation Hydra. It would be invisible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- GJ 9721B 0.00 light-years
- 11 Aqr 6.34 light-years
- GJ 4187A 9.79 light-years
- SDSS J204749.61-071818.3 10.8 light-years
- HIP 102203 11.6 light-years
- 2MASSW J2130446-084520 12.8 light-years
- HIP 102115 13.2 light-years
- HIP 103150 13.7 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.