Team:UNIK Copenhagen/Mars
Why go to Mars?
“Either we’re a multi-planet species and out there exploring the stars, or we are a single-planet species waiting around for some eventual extinction event.”
- Elon Musk
Curiosity has always been a driving factor in human exploration. In the video below, Christina argues why the future of human exploration should take place in the vastness of space.
Challanges facing moss on Mars
Temperature
Since temperature fluctuates on all areas of Mars, it is vital for the survival of our moss that we test its ability to survive scathing changes in temperatures. In order for a moss to survive on the surface of Mars, it will have to be able to survive a wide range of conditions not normally encountered on earth. One of these is wildly fluctuating temperatures. Just as on Earth, the temperatures on Mars vary with the seasons. At the Equator, the warmest month (October) usually doesn’t get much hotter than 4°C, while the coldest month (March) usually gets up to around -23°C. Unlike on Earth, however, these seasonal variations pale in comparison with the variations observed in the day-to-day cycle. Between the heat of day and the chill of night, it is not unusual to see fluctuations on the order of 60°C - 80°C. In October, for instance, while the hottest average day temperature is the aforementioned 4°C, the coldest average night temperature is a teeth-rattling -73°C.
Mars surface temperature at night
Atmosphere[1]
The atmosphere of Mars has changed drastically during the planet’s history. The atmosphere has become thin which has caused the pressure to drop dramatically causing liquid water to become unstable. The cause of the loss of martian atmosphere is still unexplained and puzzles astronomers all over the world.
The martian atmosphere contains a much larger amount of carbon dioxide than on earth, at around 95.9%. The other abundant gases include oxygen (1.45%), Argon (0.0193%) and Nitrogen (0.0189%), as well as traces of carbon monoxide, neon and xeon.
UV-light [2]
Due to the loss of atmosphere there is almost no ozone layer on mars which means that there is very little protection from UV radiation from the sun. UV radiation on Mars is anywhere 200-400 nm and has a high intensity. This can be extremely harmful to any life forms present on Mars.Pressure
Due to the loss of martian atmosphere a few billion years ago the pressure on Mars has also dropped. The pressure on Mars is now 600 pc which is only about 0.1% of the pressure on earth. However the pressure may also vary by as much as 25%.
Soil Composition
The Martian surface is covered with sand, dust rocks and boulders. The reddish hue of Mars comes from iron minerals in the soil formed billions of years ago when Mars climate was warm and wet. However now the martian climate is cold and dry and rusting now happens due to superoxides that form when the dust is exposed to UV light.
However scientists also believe that a lot of water and carbon dioxide is frozen inside the ice caps on Mars. There is also a large amount of olivine on the surface of Mars, which is a mineral that is prone to weathering.
Mars Chamber [1]
Imagine being able to visit Mars on earth. With a press of a button you can change any variable, simulate any possible situation, and predict the future of Mars missions. This is not science fiction, but is achieved in the Mars Environmental Chamber at the Niels Bohr Institute.
The experiments are carried out in a so called Mars-chamber available at the University of Copenhagen under the research group ‘StarPlan’. The chamber consists of two units inside of each other: The outer unit is a big glovebox, which is accessed through an airlock which can be evacuated so that no unwanted atmospheric gasses (or moisture) can get in. Only the airlock is evacuated; the glovebox itself can handle a slightly reduced pressure, but usually a pressure (N2) is maintained inside, which is slightly higher than the outside pressure (in order to minimize the risk of leakage).
The chamber is designed to handle samples in an inactive gas (f.ex. N2 or Argon) before a sample from here is placed in a vacuum-chamber (the inner unit), which can be evacuated, supplied with a low-pressure Mars-like atmosphere (mainly CO2) and possible be heated, cooled, or irradiated by UV-light. The chamber cannot handle experiments of reduced or no gravity and also magnetic fields are difficult if the field has to be powerful or span a large volume.
Aim of Mars Chamber experiment:
Our aim is to test the survivability of moss by changing the following variables to simulate their presence on Mars:
Experiment protocols
Pressure
Samples are prepared under Optimal Growth Conditions™.
Samples are collected at t=(24)n hours, where n = 0 .. 7 Consider how the pressure and atmospheric conditions might stress moss growth. (It requires CO2 and O2 , but if the pressure drops too low it might not be able to harness such gasses for metabolism and photosynthesis.
Atmospheric composition
Samples are prepared under Optimal Growth Conditions™.UV radiation
The goal is to test whether moss can survive the radiation it will receive on the surface of Mars.To set up radiation experiment, we set up Optimal Growth Conditions™ for the moss, but alter the radiation the moss will receive. This is done in the Mars Chamber, where we introduce a UV source, and vary the distance of the moss to the lamp, producing a UV gradient.
Samples are collected at t=(24)n hours, where n = 0 .. 7
Conclusion
While we did not carry out these experiments due to time pressure and our main focus being the temperature variable which could not be tested in the Mars Chmaber, we will strongly suggest that next year's team carry out the experiments. The Mars Chamber is highly equipped to simulate the martian environment and the other variables that come into play when evaluating whether or not moss could survive on Mars.
References:
[1] Kajtar, Rita (2014).Mars Environmental Chamber for Simulation of
Weathering Processes on Mars. Unpublished master's thesis, University of Copenhagen
[2] http://tomatosphere.org/teachers/mars-environment