biosatellite

A biosatellite is a satellite designed to carry out biological experiments in space. Its payloads typically include living organisms such as microorganisms, plants, and small animals, together with equipment needed to monitor physiology, development, and behavior in microgravity and exposure to space radiation. The objective is to understand how spaceflight alters biology and to apply findings to human space travel, biotechnology, and life-support design.

History: The first American biosatellite program ran in the late 1960s, with missions Biosatellite I, II and III, which studied basic physiological and developmental responses of organisms in orbit. Concurrently, the Soviet Union developed the Bion program beginning in the 1970s, conducting longer-duration experiments with a range of organisms to investigate reproduction, growth, and adaptation in space.

Payloads and methods: Biosatellites carry habitats, incubators, telemetry, and autonomous life-support or environmental-control systems for the experiments. Data collected include growth rates, genetic expression, immune responses, radiation effects, and tissue changes, enabling comparisons between space and terrestrial conditions.

Legacy and current status: In later decades, many biological experiments moved to space stations or ground-based simulations, reducing the use of dedicated biosatellites. Nevertheless, some small, dedicated missions continue to fly to study specific biological questions, and the term remains in use to describe satellites used for space biology experiments.