For the first time in humankind’s history of space exploration, one of the most critical components of our planet will make the trip beyond our atmosphere – dirt. Soil from Earth just hitched a ride to the International Space Station, making it the first time natural, unmodified dirt has been to space.
Growing plants in space has become a fairly commonplace occurrence over the past couple of decades, with Russian astronauts eating plants grown in space since around 2003. American astronauts aboard the ISS first ate a crop of Red Romaine lettuce back in 2015. Along with dozens of other experiments, we know for a fact that edible food can be grown in space. However, it’s only been done using hydroponic systems, engineered growth media, and highly modified mineral soils. According to Morgan Irons, a doctoral student in soil and crop sciences at Cornell, this will be the first time scientists have ever studied natural Earth soil in space. Another soil sample from Germany as well as a sample containing biochar from the company bio365 are included in the ISS delivery.
The big question researchers want to answer is how gravity impacts natural soil, which is filled with its own ecosystem of fungi, bacteria, and a wealth of other microorganisms. According to Irons, the study aims to “understand the impact of gravity on fungal and microbial systems in the context of soil aggregate stability.” Soil aggregates consist of particles that bind to one another for carbon sequestration, nutrient retention and soil aeration. Aggregation is considered a soil-health indicator that depends on fungal and microbial adhesives to bind mineral and organic matter.
Johannes Lehmann, professor of soil science in the College of Agriculture and Life Sciences and principal investigator of the project, calls it “a bit of a nerdy historic moment.” The work is part of NASA’s plan to discover methods for growing vegetables in space is part of a larger effort. The space agency hopes to put scientists on Mars as soon as 2030. Establishing human colonies on the inhospitable Red Planet, some 50 million miles away, hinges on many factors.
You might think that astronauts and other deep-space travelers could get their nutritional needs from the freeze-dried and pre-packaged foods that are specially designed for consuming off-Earth. While these are packed with nutrients to cover dietary needs, those vitamins and minerals break down over time, which presents a serious problem for ambitious space missions that could last months or even years. Think of sailors suffering from scurvy on long-distance sea journeys, which killed about half of them on any given trip before they figured out that citrus fruits, full of vitamin C, could keep them healthy.
The researchers sending their soil samples to space also hope the experiments could lead to a better understanding of its unique properties that can help scientists and farmers here on Earth. (Sources: Nature, Cornell Chronicle, NASA)