Planetary nebula
NGC 40
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 | Cepheus |
| Distance | 620 pc (2.0 thousand ly) |
| Diameter | 0.5 ly |
| Central star | V 11.6 · WC 8 |
| Expansion speed | 29 km/s |
| PN G name | PN G120.0+09.8 |
| Source | Strasbourg–ESO PN Catalogue |
| Right ascension (J2000) | 0h 13m 01.0s |
| Declination (J2000) | +72° 31′ 20″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 17° S. North of latitude 17° N it never sets. It stands highest at midnight in September, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 4. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 36 million years.