Nebula
Sh2-54
H II region
A cloud of ionised hydrogen (H II region): a stellar nursery glowing in the ultraviolet light of the young, hot O and B stars inside it. The distance follows from the gas’s radial velocity and the Galaxy’s rotation curve (kinematic method).
| Type | Nebula |
|---|---|
| Constellation | Serpens |
| Distance | 2,430 pc (7.9 thousand ly) · estimated |
| Diameter | 20.9 ly |
| WISE name | G018.669+01.965 |
| Catalogue status | Known H II region |
| Source | WISE H II Catalog v3.0 |
| Right ascension (J2000) | 18h 17m 53.7s |
| Declination (J2000) | −11° 44′ 28″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 78° N. South of latitude 78° S 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 7,926 years ago. At that time the first farming villages were being founded; there was no writing yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 141 million years.