NGC 6888 - Crescent Nebula, is a cosmic bubble about 25 ly across, blown by winds from its central, bright, massive star. NGC 6888's central star is classified as a Wolf-Rayet star (WR 136). NGC 6888 is about 5000 ly away in the constellation Cygnus.
Wolf-Rayet Nebula is a nebula which surrounds a Wolf-Rayet star. There are different types of WR-nebula, based on their formation mechanism: 1.HII regions 2.ejecta-type nebulae 3.wind-blown bubbles 4.neutral hydrogen voids and shells (may be associated gas). The nebula shown is a 'wind-blown bubbles' type.
M20 / NGC 6514: Trifid Nebula. This nebula is in Sagittarius. Its name means 'divided into three lobes.' The object is an unusual combination of an open cluster of stars; an emission nebula; a reflection nebula and a dark nebula. Distance to Earth: 5200 ly