PubMed1992
Even the short period (6-7 min) of real microgravity during Sounding Rocket (SR) flights has provided important basic new information about the influence of the lack of gravity on particular developmental processes. However some of the reports also clearly revealed the need of an increased number of larger samples per experiment. The SR provides a very appropriate way for testing of specific flight hardware designed for experiments on long-duration missions. It was stated that the number of flight opportunities should be extended, in order to keep scientists interested in the performance of Space experiments. To this end ESA and USSR have started to collaborate in the BIOKOSMOS-9 Mission with the aim of continuing that collaboration in the future, to provide additional unmanned flight opportunities with a duration of 10-14 days. The reports on experiments performed on Biokosmos-9 showed that such missions can be a very useful extension of flight opportunities, although several of the experimental conditions should be improved. In comparison with the 1988 COSPAR meeting, the material presented at the 1990 COSPAR Session on Developmental Biology showed considerable progress in methodology: the more descriptive phase is over, the period of the actual microgravity-experiments has started, and cell- and molecular biological approaches are increasingly applied. It also became clear that in experiments with relatively small cells (plant cells, human A431 epidermoid carcinoma cells and lymphocytes) the experimental results from flight experiments were often identical to those obtained in simulated microgravity. When applicable to the biological systems involved, users should more often consider the application of such Earth-based methods, that is not only in preparation of a real Space experiment. Finally, it was emphasized that some of the results from earlier experiments, which were assumed to demonstrate real microgravity effects, might have only seemingly been due to the microgravity conditions. Instead, they could have been caused secondarily by factors such as the lack of convection in surrounding media. It is important to test this possibility in future experiments.