Time
10 min introduction
20-30 min design experiments
35-50 min conduct experiments (some tests may need to be left overnight)
20-30 min discuss experiments
Grouping
Groups of 2-3 students
Materials
For all tests:
- A copy of the Testing Martian Soils handout for each student
- permanent markers
- masking tape or labeling tape
- hand lenses
For soil samples, enough for a class of 30 students in teams of 3:
- 30 ziplock bags
- 3 cups clean playground sand (no organic material should be present so carefully strain or wash the sand if necessary)
- 8 packages fast-acting yeast (2 ounces total)
- 4 Alkaseltzer® tablets, crushed
For nutrient milkshake:
- 500 ml distilled water
- 85 g table sugar (around 6 tablespoons)
- 85 g all purpose white flour (around 6 tablespoons)
- 1 liter bottle or flask
For agar plates (see Life Trap activity for ordering information):
- 50 sterile disposable plastic 15 mm x 100 mm Petri dishes
- 15 g agar agar powder
- 2 beef bouillon cubes
- 40 g table sugar (around 3 tablespoons) ** Unlike the plates made for the Life Trap activity, sugar is required for agar plates that yeast will happily grow on. If your agar agar powder is pre-sweetened, then no additional sugar is necessary. **
- 1 liter distilled water
- stove and large pot for preparing nutrient agar and steam sterilizing the Q tips
- Q tips
- paper towels
- bleach
For organic molecules tests (see Testing for Life activity for ordering information):
- Copy of test station directions at each test station (see Testing for Life activity)
- Biuret solution
- Benedict’s solution
- Iodine tincture
- beakers or cups
- test tubes
- test tube racks
- eye droppers
- trays or bins to keep the materials for each test station
- small 100 ml beakers or squeeze bottles to contain test reagents
- Optional: large squeeze bottles of water (500 ml disposable plastic water bottles are fine) for rinsing test tubes at test stations rather than going to a sink
- large beakers or cups to dump waste materials
- hot plate or source of boiling water
- insulated containers such as a thermos or Styrofoam cup for creating a hot water bath
- Optional: thermometers to monitor the temperature in the hot water bath
- disposable latex gloves
For microscope test:
- dissecting scope, although a light microscope at low power will also work
- slides or Petri dishes
Optional for introduction:
- computer with digital projector to show students slide shows or videos of the Mars Exploration Rover Mission (see Sources section for details)
Setting
Classroom
