Aliens inferred

Abstract

The discovery of extraterrestrial (ET) life would be a revelation of scientific and cultural magnitude that rivals Darwin's theory of evolution and Copernicus's hypothesis that the Earth revolves around the Sun. But while conjecture about the existence of ET life predates industrialism, it is only within the past century or so that technology has developed to the point where humans can add empirical observations to centuries of wondering. With rapid advancements in biological, chemical, and technological science, discovering ET life could be within reach. However, investigations of other planetary environments are still on the edge of technological capability and researchers may need to rely on indirect signs of life to make a detection. These signs may be difficult to interpret. This thesis surveys some of the main techniques and technologies that researchers currently use or are developing to search for alien life. It also teases out some limitations and ambiguity inherent in contemporary data interpretation.