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ISS experiment exposes biological limits in space

Amy Tyndall, News reporter
Jan 3, 2015, 17:38 UTC

Sen—As popular as wearable cameras are nowadays, it is unlikely that the average person will be able to capture an image quite as impressive as this below.

Taken with the helmet camera of Oleg Artemyev, the photograph shows the Russian cosmonaut on a precarious spacewalk outside the International Space Station (ISS) last August during the installation of ESA's EXPOSE-R2 facility which gives 46 organisms a front-seat view of the Earth as they hurtle through space.


Image taken by Oleg Artemyev with his helmet cam, as he carries out EVA-39 to install the EXPOSE-R2 facility and BOSS experiment on 18 August 2014. Image credit: Roscosmos.

The EXPOSE facilities were designed by ESA to subject a variety of biological and chemical samples to the conditions associated with the vacuum of space and to record the incoming data, with the aim of seeing how organisms react to the harsh conditions of spaceflight in the long term. 

Along with fellow cosmonaut Alexander Skvortsov, Artemyev carried out EVA-39 on 18 August 2014 to mount EXPOSE-R2 onto the side of the ISS and install its first experiment, BOSS (Biofilm Organisms Surfing Space). The BOSS experiment, led by Dr P. Rettberg of the German Aerospace Centre (DLR), consists of 46 species of bacteria, fungi and arthropods, and was launched on a Progress supply ship to the ISS back in July 2014.

Earth's atmosphere acts as the first line of defence for life on the surface, filtering out the harshest radiation and protecting us from the surrounding vacuum. This means that the only way to know the full extent of the effect that space has on biological and chemical components, and whether they can survive at all, is to send them there and test their limits. Each sample has been duplicated or triplicated to ensure that the viewed results are real and not an anomalous one-off.

As the samples are exposed any water or gas they contain is removed by the vacuum, and the surrounding temperature will vary between –12°C and 40°C depending on where the Station is in its orbit around the Earth. However, some samples will not be fully subjected to the emptiness of space: according to ESA, EXPOSE also has special compartments that recreate the martian atmosphere by letting in some sunlight and retaining slight pressure.

“The martian sections allow us to investigate to what extent terrestrial life can cope with the extreme conditions on the Red Planet. We hope they will contribute to the discussion about the possibility of life on Mars," ESA project scientist for EXPOSE, René Demets, explained on the ESA website.


The EXPOSE-R2 facility showing its sample-containing compartments that will be fully exposed to outer space until February 2016. Image credit: Roscosmos.

During EVA-40 on 22 October 2014, cosmonauts Maksim Viktorovich Surayev and Alexander Samokutyaev removed the cover of the BOSS experiement that protected the samples.

This meant that the organisms were now fully exposed for the next 18 months to the vacuum, changing temperatures and UV radiation of outer space, with scientists eagerly awaiting the results back on Earth.