Little Ghost Nebula

Lore & Background

The Little Ghost Nebula was discovered by William Herschel in 1784. It is described as round and planet-shaped, and relatively faint. The nebula's central star is a white dwarf with a spectral type of [WO3], indicating a spectrum similar to an oxygen-rich Wolf–Rayet star. An analysis of Gaia data suggests that the central star may be a binary system, though it was monitored by the Kepler space telescope and found not to be variable. The nebula's main ring structure is about a light-year across, and its glow comes from ionized oxygen (blue), hydrogen (green), and nitrogen (red).

Reader's Guide

The Little Ghost Nebula is significant as a planetary nebula that illustrates the late stages of stellar evolution, where a dying star sheds its outer layers and ionizes them. Its central star's [WO3] spectral type places it among oxygen-rich Wolf–Rayet stars, a rare and hot class. The possibility that it is a binary system, suggested by Gaia data, adds to its interest for studies of stellar interactions. The nebula's non-variability as observed by Kepler provides a baseline for understanding its central star's stability. It should not be confused with the Ghost Nebula (Sh2-136) or the Ghost Head Nebula (NGC 2080). A notable event occurred on 15 June 2011, when the nebula was occulted by the Moon during a total lunar eclipse visible over Northeast Africa, Arabia, South Asia, and the northern Indian Ocean.

Did You Know?

• Its central star has a spectral type of [WO3], similar to an oxygen-rich Wolf–Rayet star.
• The nebula's main ring is about one light-year across.