Space Exploration

Red Earth – can life grow on Mars?

Exploring Martian soil and NASA’s ‘Spuds in Space’

February 20th 2015 | Montana | Christopher Beddow


Photograph by NASA

In the year 2000, the National Aeronautics and Space Administration (NASA) supported a project called Spuds in Space, where simulated Martian soil called JSC Mars-1 and potato seedlings were transported off the earth on the space shuttle Atlantis.

The idea was to see if the crop would grow in a combination of alien soil and the artificial atmosphere of a space shuttle. The potato would theoretically provide food while also, along with other possible plants, initiating the natural process of cleaning the air from carbon dioxide. This was a small experiment, initiated with the help of middle school students in potato-famous Idaho; its repercussions, however, could emerge decades later in real Martian soil.

The potato has evolved to grow on earth only in certain conditions. Like any plant it has its native environment, as well as a range of regions where it has been successfully introduced. Mars may not be Antarctica or the Sahara Desert, but despite having abundant topsoil it still has more extreme variables than anywhere on earth – more solar radiation, a different atmospheric content, and lower atmospheric pressure. The Spuds in Space project was designed to find out whether or not the potato could be grown in Martian soil with human-controlled conditions such as protection from radiation, adjusted pressure, and an artificial atmosphere. With these measures in place, the only remaining question is whether or not Mars’s red soil itself would capable of nourishing a potato just as well as a field outside of Idaho Falls. The answer lies in an examination of the makeup of Martian soil.

Martian soil

Instruments onboard the Viking lander began collecting information about Martian soil after reaching Mars in the summer of 1976. Over two decades later, the Sojourner lander of the Mars Pathfinder also reached the Martian surface and gathered more up to date readings. In 1998, researchers at NASA’s Johnson Space Center began to develop JSC Mars-1 soil after determining its properties were very similar to the soil near the famous Hawaiian volcano Mauna Kea. This soil is tephra, a layer of volcanic ash which has been an integral part of agriculture in many regions of the world including Polynesia and Iceland.

However, Martian soil can vary greatly in its composition, and it is not all tephra. JSC-1 Mars corresponds very likely to the brightest red areas of the Martian surface. Meanwhile, many other properties of the soil are unknown. Since 2008, it has continued to be tested for nutrients, acidity, and other properties that shape how it may interact with organic compounds and biological organisms. The essential ingredients for life appear to be a combination of these organic compounds – that is, chemical compounds containing carbon with both water and heat. While the surface of Mars is known to reach up to 20 degrees centigrade, the sort of heat involved in biogenesis is more akin to something found in a volcanic environment. Water, meanwhile, was not known to exist on Mars until very recently when the Curiosity rover confirmed that in some places it was notably abundant in the soil.

The low heat on Mars suggests that life may not form on a whim, but what if it were indeed introduced in the form of an already existing Earthly seed? Indeed, there is a possibility that the potato, among other plants, could be grown on Mars if the conditions are compatible.

Photograph by Bryan Versteeg

Atmospheric pressure would have to be controlled much like the pressure in the cabin of an airliner, most likely using a greenhouse-like structure. Plants grow poorly in low pressure areas like that on Mars, even if they are given an earth-like atmospheric content and are protected from high levels of radiation. Providing additional water, whilst difficult, would be made much more convenient if it becomes possible to collect it at volume on Mars itself.

Agricultural prospects

The solution to the potato question, then, lies in engineered adaptation. Explorers to the Americas found that, just like in modern experiments with Martian soil, many of their crops did not comply well with the new environment despite having rich soil. Failure to predict which crops would thrive brought the risk of starvation, but also forced adaptation on the part of humans. Luckily, many were able to experiment with local crops as well as new forms of agriculture often learned from natives. With Mars, modern technology presents the novel approach of modifying plants on a genetic level to adjust to lower pressures rather than undergoing trial and error like in the past. This could serve to eliminate the need for excessive water use and may even pave the way for further modifications involving the types of atmospheric gases a plant can tolerate and the amount of radiation it can withstand – although that is pure speculation at this point in time.

Viking settlers in Iceland triggered a process of ecological changes that lasted until the 20th Century, leaving much of the island’s surface as barren as Mars itself. After NASA’s own Viking landers reached Mars, we have begun a new era of exploration that, this time, comes with a degree of ecological caution as we consider not only the romance of human presence on Mars but the sustainability of such an endeavour. To survive without costly and life-or-death dependency on our home, a human settlement on Mars would most certainly need to develop self-sufficiency in the long term.

Future spuds

Fundamentally, the great promise of the Spuds in Space concept and the research that has come in the nearly two decades following is that humanity is taking careful steps to understand the importance and opportunity of agriculture beyond our planet. Experiments with JSC-1 Mars soil have found that potatoes, among other edible plants, can indeed be grown if the environment is controlled.

There may be no life to be found on Mars just yet, but it appears to be only a matter of time before we set foot onto its surface and, quite literally, seek to take root in a new, red earth.