Pinwheel nebula

A pinwheel nebula is a class of Wolf–Rayet nebula in the shape of a pinwheel.

Wolf–Rayet nebulae

Main article: Wolf–Rayet nebula

Animation of WR 104's pinwheel nebula

Some Wolf–Rayet stars are surrounded by pinwheel nebulae. These nebulae are formed from the dust that is spewed out of a binary star system. The stellar winds of the two stars collide and form two dust lanes that spiral outward with the rotation of the system.^[1]

The first such nebula, located around WR 104, was discovered using the Keck Observatory in 1999.^[2] The discovery of a second, WR 98a, established pinwheel nebulae as a distinct class of nebula.^[1]

Pinwheel Galaxy

M101, better known as the Pinwheel Galaxy, was historically known as the Pinwheel Nebula^[3][4] before Edwin Hubble realized that many spiral shaped nebulae were actually 'island universes' or what we now call galaxies.^[5]