Origin of life

It still is a challenge for scientists and philosophers to define life, since the definition must include all life we are familiar with, but at the same time not exclude life forms that might be fundamentally different from life we know on earth.

Life can be defined as:

• A network of regulatory mechanisms (negative feedbacks) inferior to the potential of expansion and reproduction (positive feedback).

• Matter that can reproduce itself and evolve as survival dictates.

• Living things that produce and maintain without help.

• Living things that are themodynamic systems and have an organized molecular structure.

NASAs definition states that life is a self sustained chemical system capable of undergoing Darwinian evolution.

• Yes, extraterrestrial life could be possible.

• Terrestrial life (latin: Terra = Erth) mean all parts of life that toke place on the earth.

• Sufficient quantities of carbon and the other major life-forming elements, along with water, may enable the formation of living organisms on other planets with a chemical make-up and temperature range similar to that of Earth.

• Terrestrial planets, such as Earth, are formed from "stardust" in a process that allows for the possibility of other planets having formed with compositions similar to Earth’s.