Loading and Retrieval

Space life sciences experiments often require that research subjects be installed in the spacecraft in a precisely timed manner. For instance, if germination of plant seeds is to occur in space, or embryos are to undergo a particular stage of cell division, they must be in a specific stage of development at the time of launch. If the launch is delayed because of inclement weather or a system malfunction, research subjects frequently must be unloaded from the spacecraft and a fresh group of subjects installed once a new launch time is set. To accommodate such an eventuality, researchers must have several backup subject groups, in varying stages of development, prepared for flight.

In order to prepare the spacecraft itself for launch, all payloads, including those accommodating live research subjects, must be integrated into the spacecraft as early as several months before launch. Only critical items, such as the subjects themselves, can be loaded up to several hours prior to launch. Installation of habitats with living organisms may require special handling, depending on the structure and orientation of the spacecraft. Installation of research subjects into the Space Shuttle, which is oriented vertically during the prelaunch period, can involve lowering the organisms in their hardware units through a tunnel into the holding racks in the Spacelab or SpaceHab (Figure 3-09).

Figure 3-09. Biological specimens and perishable items may be loaded in the Space Shuttle middeck or pressurized module only a few hours before launch. When it is necessaiy to install scientific samples and specimens in the module, it can be entered through a vertical access kit. Source ESA.

Because organisms begin to readapt to Earth's gravity immediately upon landing, dissection and tissue preservation in orbit or quick access postflight is critical to the value of the science. Organisms can be removed from manned spacecraft such as the Space Shuttle within a few hours after touching down. Removal from the unmanned Foton Biosatellite occurs several hours postflight because mission personnel must first locate, and then travel to, the landing site. Transport from the spacecraft to ground laboratories may be time-consuming when the biosatellite lands some distance away from Moscow. In such instances, a temporary field laboratory is set up at the landing site to allow scientists to examine the subjects before readaptation occurs. The issue of postflight readaptation highlights the value of inflight data and tissue collection.

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