... 15.09.2009 . ... Credit: Daniel L pez , IAC Explanation: NGC 6888, also known as the Crescent Nebula, is a cosmic bubble about 25 light-years across, blown by winds from its central, bright, massive star. ... NGC 6888's central star is classified as a Wolf-Rayet star (WR 136). The star is shedding its outer envelope in a strong stellar wind , ejecting the equivalent of the Sun's mass every 10,000 years. ... Found in the nebula rich constellation Cygnus, NGC 6888 is about 5,000 light-years away. ...