Looking like a giant Exogorth or Space Slug from The Empire Strikes Back leaping out of an asteroid to devour the Millennium Falcon, this object is more commonly known as a "cometary globule" hence its more familiar name of CG4 and it is composed of dust and inonised gas. The Milenium Falcon here is in fact the distant galaxy ESO 257-19 and is many millions of light years further away.
It is also referred to as the Hand of God sometimes and I recon it's a very cool lookin object
Giant Space Slug
Full Frame
Galaxy ESO257-19
Mike
I'm sure there are a few other shapes in there too.....
like the sand worms from Arrakis in Dune and the Doomsday Machine from Star Trek