Long-Distance Space Travel Many scientists and engineers are working toward the goal of sending astronauts to Mars. The trip is estimated to take about 9 months each way. It is very expensive to take enough oxygen to last the whole trip. The astronauts also need enough food, and there has to be a way to get rid of excess carbon dioxide created by their cellular respiration.

Present a plan for the astronauts. Explain how growing food during space flight will help regulate carbon dioxide and oxygen levels. List the supplies the astronauts would need.