Edit this for grammatical errors, and make it grammatically sound and free of errors.
To put it simply, ecosystems are environments that have the ability support or sustain life. Earth's ecosystem consists of living organisms and composition of the atmosphere. In a way the cycle of life is somewhat similar to matter in the galaxy. Our galaxy has the "same characteristics that we associate with ecosystems if we view it on appropriately large scales of distance and time" (p. 6) The star-gas cycle, or star formation is comparable to the biological life cycle. Stars are born and eventually die out leading to formation of new stars. Star formation is dependent upon the element composition of clouds, thus certain conditions are required for stars to be born. The term ecosystem can be applied to discussion of galaxies, it is related and already discussed as galactic ecosystems and ecology.