Planetary nebula
A 77
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. The distance is a statistical estimate, uncertain by 30–50 %.
| Type | Planetary nebula |
|---|---|
| Constellation | Cepheus |
| Distance | 1,280 pc (4.2 thousand ly) · estimated |
| Diameter | 0.8 ly |
| Central star | V 15.7 |
| Expansion speed | 8 km/s |
| PN G name | PN G097.5+03.1 |
| Source | Strasbourg–ESO PN Catalogue |
| Right ascension (J2000) | 21h 32m 10.7s |
| Declination (J2000) | +55° 52′ 46″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 34° S. North of latitude 34° 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 4,175 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 74 million years.