© CTIO/NOIRLab/DOE/NSF/AURA
The Dark Energy Camera (DECam) has captured an ominous and ghostly hand reaching from the Milky Way from a distant edge-on spiral galaxy. But despite its nickname, ‘God’s Hand’, there’s nothing supernatural about this structure – yet that doesn’t make it any less awe-inspiring. God’s Hand is actually a cometary globule officially known as CG 4. It is located around 1,300 light years from Earth within our Milky Way and is seen in the constellation of Puppis. Cometary globules are a hard-to-detect subclass of so-called Bok globules, which are isolated and dense clouds of gas and dust surrounded by hot, ionised material.
Despite their name, cometary globules have nothing to do with comets. The moniker actually comes from the fact that these nebulae have had material dragged away from them, creating a long tail that resembles the characteristic tail of a comet. Cometary globules remain somewhat mysterious because the cause of their structure hasn’t yet been definitively determined. Scientists hypothesise that the structure of cometary globules could be created by stellar winds that flow from the hot, massive stars surrounding them, or from the supernovae that occur when these stars die.