Asteria — interactive night sky map
NGC 40 is a planetary nebula in the constellation Cepheus with an apparent magnitude of 11.9, spanning about 1 arcminutes. A telescope is needed to observe it.
It is best placed in the evening sky around September. It is visible from the whole northern hemisphere and from southern latitudes down to about 17°S. It is circumpolar (never sets) north of latitude 17°N.