The Miller and Urey experiment (or Urey–Miller experiment) was an experiment

Experiment

An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...

 that simulated hypothetical conditions thought at the time to be present on the early Earth

Early Earth

The "Early Earth" is a term usually defined as Earth's first billion years, or gigayear. On the geologic time scale, the "early Earth" comprises all of the Hadean eon , as well as the Eoarchean and part of the Paleoarchean eras of the Archean eon.This period of Earth's history, being its earliest,...

, and tested for the occurrence of chemical origins of life

Abiogenesis

Abiogenesis or biopoesis is the study of how biological life arises from inorganic matter through natural processes, and the method by which life on Earth arose...

. Specifically, the experiment tested Alexander Oparin's and J. B. S. Haldane

J. B. S. Haldane

John Burdon Sanderson Haldane FRS , known as Jack , was a British-born geneticist and evolutionary biologist. A staunch Marxist, he was critical of Britain's role in the Suez Crisis, and chose to leave Oxford and moved to India and became an Indian citizen...

's hypothesis that conditions on the primitive Earth favored chemical reactions that synthesized organic compound

Organic compound

An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

s from inorganic precursors. Considered to be the classic experiment on the origin of life

Abiogenesis

Abiogenesis or biopoesis is the study of how biological life arises from inorganic matter through natural processes, and the method by which life on Earth arose...

, it was conducted in 1952 and published in 1953 by Stanley Miller

Stanley Miller

Stanley Lloyd Miller was an American chemist and biologist who is known for his studies into the origin of life, particularly the Miller–Urey experiment which demonstrated that organic compounds can be created by fairly simple physical processes from inorganic substances...

 and Harold Urey

Harold Urey

Harold Clayton Urey was an American physical chemist whose pioneering work on isotopes earned him the Nobel Prize in Chemistry in 1934...

 at the University of Chicago

University of Chicago

The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...

.

After Miller's death in 2007, scientists examining sealed vials preserved from the original experiments were able to show that there were actually well over 20 different amino acids produced in Miller's original experiments.