Deep-Sky Object

Protoplanetary Nebula

The brief stage before a planetary nebula forms.

A short-lived (a few thousand years) phase when an evolved star's ejecta is illuminated only in reflected light, before the core ionises the shell.

Overview

A short-lived (a few thousand years) phase when an evolved star's ejecta is illuminated only in reflected light, before the core ionises the shell.

See also