Growing Plants for NASA — Challenges in Lunar and Martian Agriculture©

INTRODUCTION Technology advanced rapidly during the 20th Century. One hundred years ago, 17 Dec. 1903, the Wright Brothers fl ew the world’s fi rst powered aircraft at Kitty Hawk, North Carolina. It was a fl ight of 37 m (120 ft) that lasted 12 sec at a maximum speed of 16 kmph (10 mph). Forty-four years later Chuck Yeager would break the sound barrier — Mach 1 at 1086 kmph (675 mph). Twenty-two years after that in 1969, Neil Armstrong landed on the moon. So what is the role of plants for human life support? Plants reduce the level of carbon dioxide (CO2) and produce oxygen (O2) during photosynthesis. They can also help convert wastewater into potable water through transpiration and subsequent condensation and collection of clean water. Plants also produce carbohydrates and food for human consumption (Fig. 1). In the international space station and NASA’s space shuttle, physical-chemical methods are primarily used to produce oxygen and absorb or vent carbon dioxide from the cabin atmosphere (Fig. 2). NASA plans to use plants to supplement physical-chemical systems to produce oxygen and absorb carbon dioxide. Plants also have a role in supplementing human nutrition as part of NASA’s “salad bar” program of fresh greens and vegetables. Plants are also important for the psychological well being of the crew.