Planetary nebula
A 78
Planetary nebula
A shell of gas thrown off by a dying Sun-like star, glowing in the ultraviolet light of the hot core at its centre. Within a few tens of thousands of years it will disperse and fade from view.
| Type | Planetary nebula |
|---|---|
| Constellation | Cygnus |
| Distance | 1,630 pc (5.3 thousand ly) |
| Diameter | 2.8 ly |
| Central star | V 13.2 · O5fek |
| Expansion speed | 27 km/s |
| PN G name | PN G081.2-14.9 |
| Source | Strasbourg–ESO PN Catalogue |
| Right ascension (J2000) | 21h 35m 29.5s |
| Declination (J2000) | +31° 41′ 45″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 58° S. North of latitude 58° N it never sets. 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 5,316 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 94 million years.