Science. 1985 Jun 21;228(4706):1389-95. doi: 10.1126/science.228.4706.1389.
Young stellar objects of both high and low luminosity emit energetic jets or winds of material that are often highly collimated and often bipolar. Near the stars, turbulent swept-up gas is observed in the emission of interstellar molecules such as carbon monoxide, and small, bright regions of water maser emission and the nebulous bright patches known as Herbig-Haro objects appear to be participating in the outflows. There are striking changes in chemical abundances associated with the attendant shocks. Probably every star goes through this phase, which may mark the end of its period of accretion.
年轻的高、低光度恒星都会发射出高能物质射流或物质风，这些射流通常具有高度的准直性，并且经常呈现双极形态。在恒星附近，可以观察到星际分子（如一氧化碳）的发射中存在被激波扫过的气体的湍动，并且小而亮的水脉泽发射区和被称为赫比格-哈罗天体的朦胧亮斑似乎都参与到了外流过程中。与伴随的激波相关的化学丰度存在显著变化。可能每颗恒星都要经历这个阶段，这可能标志着它吸积阶段的结束。
