New Delhi: During a spacewalk outside the International Space Station (ISS) under the Russian program, Russian cosmonauts took samples with cotton swabs from the station’s external surface, probing places where the accumulation of fuel wastes were discharged during the engines’ operation or at places where the station’s surface is more obscure.

These samples were sent back to Earth for examination.

Now, Russian cosmonaut Anton Shkaplerov has revealed that somehow, the samples contain living bacteria. While they are being studied on Earth, they don't pose any sort of danger, Shkaplerov told Russian news agency TASS.

“It turns out that somehow these swabs reveal bacteria that were absent during the launch of the ISS module. That is, they have come from outer space and settled along the external surface. They are being studied so far and it seems that they pose no danger,” the Russian astronaut said.

Some terrestrial bacteria also survived on the space station’s external surface, though they had remained within a space vacuum for three years. In addition to that, they underwent sharp swings in temperature from minus 150 to plus 150 degrees Celsius, he noted.

The bacteria entered the space station through tablet Pcs and various other materials that are placed aboard the ISS for long periods to study their behavior in outer space.

Shkaplerov will be the head of the next space station crew, which is set to take off to the world’s sole orbiter on December 17.