Activity 2: Developing a Greenhouse Plan for Mars

This is a team activity. Each team should consist of 4 to 6 students. The task is to develop a greenhouse plan that will provide 6 astronauts with approximately 50% of their food requirements for a 400 day stay on the planet Mars.

The completed plan can be presented to the other teams of the class. Full scientific justification for each team's plan should be included as part of their presentation.

Tasks

  1. Determine the daily energy requirements for 6 working adults.
  2. Determine the minimum daily protein requirements for 6 working adults.
  3. Select vegetable or fruit products that will meet these protein and energy requirements.
  4. Determine the minimum area needed to grow the crops that will meet the basic energy and protein requirements.
  5. Notice that the chart Characteristics of Various Crops in the Resources section that follows is only a subset of the possible crops that could be grown on Mars. Each team should research at least one additional crop and add it to the list.

Dehydrated fruit

Figure 3: Numerous fruits and vegetables can be successfully dehydrated to extend their storage life. Eaten fresh these foods provide an important source of water.

Extension Activities

  1. The intensity of sunlight on Mars is approximately one half the intensity of sunlight on the Earth's surface. Will there be sufficient sunlight on Mars for plants to be photosynthetically successful?
  2. Conduct experiments to determine the effects of reduced light on the time required for fruits or vegetables to reach maturity.
  3. Martian soil may be chemically active and therefore unsuitable for plant growth. An alternative is to grow the plants hydroponically. Design a hydroponic system to grow tomatoes that requires the absolute minimum amount of water.
  4. On Earth the ozone layer protects most organisms from damaging solar ultraviolet light. On Mars there is no ozone layer. Although the ultraviolet intensity at the top of the atmosphere on Mars is less, owing to Mars' greater distance from the Sun, the ultraviolet light will still be lethal to plants (i.e. the UV environment at the Martian surface is much more harsh than at the surface of the Earth).
    • Plants (and humans) exposed to direct sunlight on Earth still receive dangerous amounts of ultraviolet light in spite of the ozone layer. How do the green leaves of plants protect themselves from UV damage?
    • Not all plants are equally sensitive to ultraviolet light. Conduct a literature search to find some UV hardy plants. Might it be possible to genetically engineer their UV-resistant coding into Martian crops?
    • Ultraviolet light is extremely damaging to plastics. Are there light-weight, flexible transparent materials that could be used to cover Martian greenhouses that are not only UV tolerant but filter out the UV as well?
  5. Even sun-hardy plants grown indoors during the winter months need to be "conditioned" or "acclimatized" before they can be left outside in direct sunlight in the spring, otherwise the plant risks being killed. Conduct a literature search related to this phenomenon. Specifically, how do plants acclimatize themselves?
  6. To get an idea of the effects that food (and diet) can have on an expedition, perform a literature search on the Franklin Expedition, which set out in 1845 to explore the Canadian High Arctic.
  7. Did you know that astronauts get to choose their own menus from a list of predetermined items prior to a space shuttle flight? Visit the Canadian Astronaut Missions section of the Canadian Space Agency web site to investigate the menus selected by various Canadian Space Agency astronauts such as Dr. Steve MacLean or Dr. Dave Williams. Do their meals meet all the criteria for a well balanced diet?
  8. Investigate the role of vitamins and minerals in the human diet. Will astronauts on long duration missions need to take vitamin and mineral supplements?