"The pillars are composed of cool molecular hydrogen and dust that are being eroded by photoevaporation from the ultraviolet light of relatively close and hot stars. The leftmost pillar is about four light years in length. The finger-like protrusions at the top of the clouds are larger than our solar system, and are made visible by the shadows of evaporating gaseous globules (EGGs), which shields the gas behind them from intense UV flux. EGGs are themselves incubators of new stars. The stars then emerge from the EGGs, which then are evaporated.Image credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA), via Wikipedia.