A Wolf-Rayet Bubble Nebula surrounds a Wolf-Rayet star. There are different types of WR-nebula, based on their formation mechanism: regions nebulae bubbles hydrogen voids and shells (may be assoc. The nebula shown is a 'wind-blown bubbles' type
“ This is a deep image of the Sword of Orion - the three stars that make up the weapon hanging off the belt of this famous celestial hunter. The image showcases the amazing mix of physical and optical.