The Ghost Nebula - vdB 141

The molecular cloud

The Ghost Nebula is catalogued as vdB 141 in Sydney van den Bergh's Catalog of Reflection Nebulae, created in 1966. Other designation of the nebula is Sh2-136 in the Sharpless catalogue. The cloud is located in the constellation of Cepheus, more precisely at the very edge of the molecular cloud complex called the Cepheus Flare, approximately 1200 light years from the Sun. The cloud is being illuminated by a few bright stars in the vicinity. Without those stars the whole cloud complex would be dark and observable only as it absorbs the light coming from stars in its background. The central part of the nebula with the ghost-like features is about 2 light years across.  The core of the dark patch on its right is collapsing due to its own gravity forming a Bok globule, identified as CB 230 (Clemens & Barvainis catalog of Bok globules, 1988).

Bok globules and CB 230

Bok globules are dense collapsing clouds of cosmic dust and gas, named after Dutch-American astronomer Bart Bok who observed them first. Bok globules are known to be some of the coldest objects in the universe. Within these globules star formation may take place, like in the case of CB 230.

In the right side of the cloud conical outflows can be observed. These outflows are originated deep in the cloud, where two stars are being in the early stages of formation. Their apparent separation is about 10", and they are formed from the same initial core. They have different masses, but their evolutionary stage is the same. These two forming stars are blowing the dust and gas around them, creating the outflows.