Stellar cocoon CRL 618
In this image singly ionised sulphur is shown in red, green represents neutral hydrogen, the blue-green colour comes from neutral oxygen and blue light is continuum light seen through a so-called Strvmgren y filter. The full extent of the nebula is 12 arcseconds from tip to tip.
The original Hubble observations were obtained in 1998 by Susan R. Trammell from University of North Carolina, and were turned into a colour image by the Hubble European Space Agency Information Centre at European Southern Observatory, Munich and A.G.G.M. Tielens from the Kapteyn Astronomical Institute in the Netherlands.