Object Analysis

The Skull Nebula (NGC 246) is a planetary nebula located in the constellation Cetus. It is roughly 1,600 light-years away. It earned its nickname from the arrangement of three stars near its center and the patchy, mottled appearance of its gas, which creates a face-like silhouette.

The central star is a white dwarf, but it is actually part of a triple star system—a rarity for planetary nebulae. The interaction between these stars and the expanding shell of gas helps explain the nebula's slightly asymmetrical and "holey" appearance.

In a telescope, the nebula appears as a faint, circular glow. One side of the "skull" is notably sharper than the other; this is because the nebula is plowing through the interstellar medium, creating a "bow shock" that compresses the gas on the leading edge.