BIOMEX Mission: Exploring Mars in Low Earth Orbit

BIOMEX Logo. Image courtesy DLR.

In their quest to understand life's potential beyond Earth, astrobiologists study how organisms might survive in numerous environments, from the surface of Mars to the ice-covered oceans of Jupiter's moon, Europa.

For now, Earth is our only example of an inhabited planet, and studying the limits of habitability on Earth is a major component of astrobiology research.

For this reason, scientists collect data from places on our planet where life is pushed to the absolute limits of adaptability, from the Antarctic to the Arctic, and from smoldering thermal vents to highly acidic rivers.

But locations like the Antarctic Dry Valleys or deep-sea vents in the Pacific aren't the only places in which astrobiologists study life as we know it.

Low Earth orbit provides an opportunity to observe Earth-life in the harsh conditions of space.

In the early hours of July 24th, 2014, a new astrobiology experiment began its journey from the Baikonur Cosmodrome in Kazakhstan to the International Space Station (ISS).

BIOMEX (Biology and Mars Experiment) launched onboard a Russian Progress cargo spacecraft and is one of four experiments that make up the EXPOSE-R2 facility, which will be mounted on the exterior of the ISS Zvezda module.

Just six hours after launch, the cargo ship successfully docked with the ISS.

Life on the Station
BIOMEX contains twelve different experimental packages that are designed to help determine life's potential on Mars.

The Institute of Planetary Research at the German Aerospace Center (DLR) is coordinating BIOMEX, but the project involves 25 participating institutions from around the world.

BIOMEX contains numerous chambers that are filled with biomolecules and organisms that include bacteria, archaea, algae, fungi, lichens and mosses.

Replicate samples spread across the compartments are subjected to a range of environmental conditions.

Some samples of each biomolecule or organism are embedded in a simulant Mars soil (ranging from just a single layer of soil to multiple layers), and other samples are left on their own to face the space environment without protection.

Various filters are also being used on the sample chambers to test exposure to different levels of radiation.

By doing this, scientists are able to simulate the solar radiation present at the martian surface. Some of the sample chambers are even pumped full of a simulated Mars atmosphere that is rich in carbon dioxide and pressurized to replicate conditions on Mars.

"To gain real insights into the behaviour of biomolecules within a martian environment, we have to check the different parameters we might encounter on Mars," explained Dr. Jean-Pierre Paul de Vera of the German Aerospace Center (DLR) and the principle investigator for BIOMEX.

"This means we will approach - as much as possible on the ISS - martian conditions, including extreme temperature regimes, martian atmosphere by using Mars-like gases in the compartments of EXPOSE-R2, and the radiation regime, which we can never simulate in the labs on Earth."

The samples will spend up to one and a half years outside the space station, and the organisms inside will be monitored with temperature sensors and dosimeters, which monitor radiation exposure.

The goal is to see how exposure to these varied environmental pressures affects the survival of the organisms and the stability of important cellular components like membrane lipids, pigments, proteins and DNA.

The results of BIOMEX will help astrobiologists understand whether or not these biological materials can cope with conditions in the space environment and on Mars, and if being buried in martian soil might aid in their survival.