Space biology

(biology) A term for the various biological sciences and disciplines that are concerned with the study of living things in the space environment.

Collectively, the various biological sciences concerned with the study of organisms and their components when exposed to the environment of space (or of a spacecraft beyond the immediate influence of Earth and its atmosphere). Space biology studies include all the biological science disciplines, such as molecular, cellular, developmental, environmental, behavioral, and radiation biology; physiology; medicine; biophysics; and biochemistry. Space biology encompasses both basic and applied sciences, and focuses on using space research to understand and resolve biological problems on Earth, as well as alleviating or preventing the deleterious physiological changes associated with space flight or habitation in non-Earth environments. See also Space.

As crewed space flight developed, medical research focused on the health and well-being of astronauts, which was paramount. This medical research has historically been included in the area of aerospace medicine. From these research efforts, directed at survival of living systems in the space environment, has evolved the broader discipline of space biology, which uses the space environment to gain an understanding of basic biological processes. See also Aerospace medicine.

Space biology considers all of the inherent physical factors of the space environment and their effects on living organisms: (1) factors due to the environment of space, such as radiation and reduced pressure; (2) factors due to the flight dynamics of spacecraft, including acceleration, weightlessness, and vibration; (3) factors due to the environment of the spacecraft, such as air composition, atmospheric pressure, toxic materials, noise, and confinement; and (4) factors due to the environment on nonterrestrial bodies, such as the level of gravity, composition of soil, and temperature extremes. Of these factors, only weightlessness and space radiation are unique to the space environment, but the effects of the other factors must be considered and mimicked in ground-based or flight controls when conducting space biological experiments. In addition, space experiments must take into consideration the physical effects of weightlessness on the environment surrounding and supporting the organisms. For example, neither gases nor liquids behave in a space environment as they do under the conditions found on Earth, as sedimentation, buoyancy, and convection do not occur in a weightless environment. See also Acceleration; Weightlessness.