The study of astrobiologists tries to explore the issue of the existence of extra-terrestrial life in the universe. As part of their job, they want to inquire into the nature of environment suitable for life beyond the Earth. To conduct their research in relevant field, they apply knowledge of different fields like biology, chemistry, geology, atmospheric science, oceanography, astronomy and aeronautical engineering. Research on astrobiology has significant role on the planning of space missions conducted by space agencies. In order to detect life beyond solar system, they endeavour to find out earth like planets and conduct in depth analysis on their atmospheric composition. The study of the origin of life on earth is an important segment of an astrobiologist’s profession. They try to explore the development process of various planets and their habitable condition with the help of their knowledge of biological and information sciences. The study of microorganisms plays a dominant role in astrobiology. These microorganisms are important for evolutionary research work. In their quest for possibility of life on other planets, astrobiologists interpret scientific data to construct hypotheses for further research. Listed below is information about the life and works of some renowned astrobiologists from all over the world.