Astronomy Picture of the Day . Close Up of the Bubble Nebula . ... 18.11.1998 . ... Credit: Hubble Heritage Team ( AURA / STScI / NASA ) Explanation: It's the bubble versus the cloud. NGC 7635, the Bubble Nebula , is being pushed out by the stellar wind of massive central star BD+602522. ... The cloud is able to contain the expansion of the bubble gas, but gets blasted by the hot radiation from the bubble's central star. ... Publications with keywords: HII region - emission nebula . ...