Claim: Pluto is in the universe.

Abiogenesis -LRB- British English : -LSB- ˌeɪˌbaɪoʊˈdʒɛnᵻsᵻs , _ - ˌbaɪə - -RSB- , -LSB- - en - ˌbiːoʊ - , _ - ˌbiːə - -RSB- -RRB- , biopoiesis , \ \ or informally , the origin of life , is the natural process by which life arises from non-living matter , such as simple organic compounds . Abiogenesis is studied through a combination of paleontology , laboratory experiments and extrapolation from the characteristics of modern organisms , and aims to determine how pre-life chemical reactions gave rise to life on Earth .   The study of abiogenesis can be geophysical , chemical , or biological , with more recent approaches attempting a synthesis of all three . Life itself is dependent upon the specialized chemistry of carbon and water and is largely based upon five different families of chemicals . Lipids are fatty molecules comprising large chemical chains of hydrocarbons and play an important role in the structure of living cell membranes , actively and passively determining the transport of other molecules into and out of cells . Carbohydrates are sugars , and as monomer units can be assembled into polymers called polysaccharides , such as cellulose , the rigid chemical of most plant cell walls . Nitrogenous bases are organic molecules in which the amine group of nitrogen , combined with two hydrogen atoms , plays an important part . Chlorophyll is based upon a porphyrin ring derived from amine monomer units , and is important in the capture of the energy needed for life . Nucleic acid monomers are made from a carbohydrate monosaccharide a nitrogenous base and one or more high energy phosphate groups . When joined together they form either the unit of inheritance , the gene , made from DNA or RNA , which translates the genetic information into protein structures . The monomer unit of a protein is usually one of 20 amino acids , comprising an amine group , a hydrocarbon , and a carboxylic acid . Through a condensation reaction , in which the carboxylic acid of one amino acid is linked to the amine of another with removal of a water molecule , a peptide bond is formed . Polymers of amino acids are termed proteins and these molecules provide many catalytic metabolic functions for living processes . Any successful theory of abiogenesis must explain the origins and interactions of these five classes of molecules .   Many approaches to abiogenesis investigate how self-replicating molecules , or their components , came into existence . It is generally thought that current life on Earth is descended from an RNA world , although RNA-based life may not have been the first life to have existed . The classic Miller -- Urey experiment and similar research demonstrated that most amino acids , the basic chemical constituents of the proteins used in all living organisms , can be synthesized from inorganic compounds under conditions intended to replicate those of the early Earth . Various external sources of energy that may have triggered these reactions have been proposed , including lightning and radiation . Other approaches -LRB- `` metabolism-first '' hypotheses -RRB- focus on understanding how catalysis in chemical systems on the early Earth might have provided the precursor molecules necessary for self-replication . Complex organic molecules have been found in the Solar System and in interstellar space , and these molecules may have provided starting material for the development of life on Earth .   The panspermia hypothesis alternatively suggests that microscopic life was distributed to the early Earth by meteoroids , asteroids and other small Solar System bodies and that life may exist throughout the Universe . It is speculated that the biochemistry of life may have begun shortly after the Big Bang , 13.8 billion years ago , during a habitable epoch when the age of the universe was only 10 to 17 million years . The panspermia hypothesis proposes that life originated outside the Earth , not how life came to be .   Nonetheless , Earth remains the only place in the Universe known to harbour life , and fossil evidence from the Earth informs most studies of abiogenesis . More than 99 % of all species of life forms , amounting to over five billion species , that ever lived on Earth are estimated to be extinct . The age of the Earth is about 4.54 billion years ; the earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago , and possibly as early as the Eoarchean Era , after geological crust started to solidify following the molten Hadean Eon . In May 2017 , evidence of the earliest known life on land may have been found in 3.48-billion-year-old geyserite and other related mineral deposits -LRB- often found around hot springs and geysers -RRB- uncovered in the Pilbara Craton of Western Australia . However , there have been a number of discoveries that suggested the earliest appearance of life on Earth was even earlier in time . Currently , microfossils within hydrothermal vent precipitates dated from 3.77 to 4.28 billion years old found in Quebec , Canada may be the oldest record of life on Earth , suggesting `` an almost instantaneous emergence of life '' after ocean formation 4.4 billion years ago . According to biologist Stephen Blair Hedges , `` If life arose relatively quickly on Earth ... then it could be common in the universe . ''