Several geckos are at risk of a rude return to earth after Russia lost control of a research satellite testing the effect of weightlessness on the small lizards' sex lives.
Russia's Progress space firm confirmed Thursday that the Foton-M4 satellite was not responding to commands from the ground to start its onboard engine and lift it to a higher orbit.
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However the company said in a statement that all other systems on the satellite, which was launched on July 19, were operating normally and information from the scientific experiments was being transmitted to the ground.
"The equipment which is working in automatic mode, and in particular the experiment with the geckos is working according to the program," said Oleg Voloshin, a spokesman of Russia's Institute of Medico-Biological Problems, which is running the experiment.
The two-month mission is monitoring by video how well the geckos sexually reproduce in space, according to the Institute's website.