Star · B8II
21 Aql
21 Aql is a bright giant star of spectral type B8II in the constellation Aquila, 683.3 light-years from the Sun.
| Other names | HIP 94477 |
|---|---|
| Constellation | Aquila |
| Distance | 683.3 light-years (209.5 pc) |
| Apparent magnitude | magnitude 5.14 |
| Absolute magnitude | magnitude −1.47 |
| Spectral type | B8II |
| Surface temperature | 11,110 K |
| Luminosity | 543 L☉ |
| Radius | 6.29 R☉ |
| Mass | 5.49 M☉ (estimated) |
| Right ascension (J2000) | 19h 13m 42.7s |
| Declination (J2000) | +2° 17′ 37″ |
| Space velocity (relative to the Sun) | 10.8 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.14). Visible from the whole Northern Hemisphere and south to latitude 88° S. It stands highest at midnight in July, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1343. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 12 million years.
The Sun seen from there
From a planet around 21 Aql, the Sun would look like a star of magnitude 11.44, in the direction where our sky has the constellation Monoceros. 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.