Specialists of the Russian Academy of Sciences' Institute of Medical and Biological Problems have failed to determine the cause and time of death of five geckos, test subjects traveling aboard the Foton-M4 research spacecraft, head of the institute's biological systems of human life support laboratory and supervisor of the Foton-M project's biological dimension Vladimir Sychev said.
"It is hard to say why they died. Probably, it could have been the influence of zero gravity or something else. Geckos stayed alive in a ground experiment with the same parameters, so we can presume it was not the environment, the temperature, the humidity or the atmospheric composition but some specific factor of the space flight [that killed the geckos]," he told Interfax-AVN.
"We can only guess what factors that could have been. Anything could have happened. It could have been zero gravity, the radiation factor or stress. It is hard to tell. We have no reasonable ideas," Sychev added.
There is no unanimity about the time of the geckos' death either. It was believed at first that they died a day or two before the landing but the post-mortem proved differently. At the same time, the geckos did not die several weeks before the landing either because their tails accumulating nutrients did not lose weight, the scientist said.
A video of the flight could have helped determine the cause and time of the geckos' death but it stopped working during the third week of the flight. "The only equipment that failed was the video camera. We saw the last video on August 5," Sychev said.
The scientist said the Foton-M4 mission was successful even though all the geckos had died.
"Here are the flight results: every experiment but the geckos' one was successful. With all the drawbacks, the mission was remarkably successful and even broke a record - not a single research spacecraft had been on a 42-day mission before," he said.
Foton-M4 landed in the Orenburg region at 1:18 p.m. on September 1, having spent 42 days in orbit. It appeared that all the five geckos (four males and a female) died. The spacecraft was also carrying fruit flies, microorganisms and seeds of higher plants, which survived the flight.
The geckos' postmortem showed they had been eating normally at first but then something happened to the spacecraft, temperatures dropped and they stopped eating. Yet it was presumed they died because of a pressure surge, not because of low temperatures or starvation.
Sychev told Interfax-AVN earlier that the loss of fruit flies would have been a great loss for the scientists. "The fruit fly experiment has enormous importance. There will be profound research based on genome analysis methods and understanding of gene expression. Up to three generations of fruit flies were born during the Foton mission," the project supervisor said.
All rights reserved by Rossiyskaya Gazeta.