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Grades 4–7Science / Chemistry40–50 minutes
Why Is Mars Red?
Students investigate why Mars appears red by conducting a simple rust experiment with steel wool and vinegar. They connect the chemical process of oxidation to the iron-rich Martian surface.
Learning Objectives
- Explain what causes the reddish color of Mars.
- Demonstrate the chemical process of oxidation (rusting).
- Compare conditions on Mars and Earth that affect oxidation.
Activities
Introduction: The Red Planet
10 minRead the Mars overview together. Discuss what iron oxide (rust) is and why it might cover an entire planet.
Rust experiment
20 minStudents soak steel wool in vinegar, place it on a paper towel, and observe over the lesson period. The steel wool visibly rusts, producing reddish-brown iron oxide.
Mars connection
10 minCompare the experiment to Mars: billions of years of iron reacting with trace oxygen and water created the rusty surface we see today.
Assessment
Students draw and label the rusting process and write a paragraph explaining why Mars is red using evidence from the experiment.