Planetary nebula
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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 | Cygnus |
| Distance | 2,300 pc (7.5 thousand ly) · estimated |
| Diameter | 0.8 ly |
| Central star | V 21.1 |
| PN G name | PN G068.6+01.1 |
| Source | Strasbourg–ESO PN Catalogue |
| Right ascension (J2000) | 19h 59m 17.7s |
| Declination (J2000) | +31° 55′ 18″ |
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 July, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 7,502 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 133 million years.