Mark H
"This bubble-like emission nebula, known as Thor's Helmet, is approximately 30 light-years across and located in the Constellation Canis Major at a distance of about 15,000 light-years. We don't know what caused the bubbles and arcs in NGC 2359, but the main culprit is the massive Wolf-Rayet star located slightly left from the image center." - Mark H from Bookmarklet
"Wolf-Rayet stars are massive, highly luminous stars that continually shed material in a stellar wind -- which commonly form bubbles in the interstellar medium. But the unusual structure of the NGC 2359 arcs indicate something more complex is going on. Experts wonder if the star is moving supersonically? Or, is there another energetic star in the vicinity? Only about 300 Wolf-Rayet stars are known to exist. NASA experts think that very massive stars become Wolf-Rayet stars just before they explode as supernova though no one has yet seen such a star explode. " - Mark H
I see a giant snail - Steve C, Team Marina