What Mars Has Not Told Us: teacher key

Mars, grade 11 edition, written for 11th grade. Curiosity found organic molecules in rock on Mars, and Perseverance found a rock with small leopard spots. As of November 2026, scientists say the key next step is to bring a sample back to Earth.

Read the book. Print this page for the key.

Questions and answers

1. Which planet is closer to the Sun, Earth or Mars?
   • Mars
   • They are the same
   • Earth (answer)
2. The crust at the InSight landing site was measured. Could it be 60 kilometers thick there?
   • Yes, anywhere on Mars
   • No, it is 15 to 47 kilometers thick there (answer)
   • Only near the poles
3. What do scientists say is the key next step for the Sapphire Canyon sample, as of November 2026?
   • Bring it back to Earth for lab tests (answer)
   • Leave it on Mars
   • Melt it on the rover
4. As of November 2026, what do scientists say about the organic molecules Curiosity found in rock on Mars?
   • More study is needed to learn where they came from (answer)
   • They prove there was life
   • They came from the rover
5. What is the main idea of how Valles Marineris formed, as of November 2026?
   • A river carved it, and that is certain
   • It probably began as a crack as Mars cooled, but how it formed is not fully known (answer)
   • It formed from a crater
6. What does biosignature mean in this book?
   • A signed name
   • A kind of rover wheel
   • A thing that might have a biological origin (answer)

Words

• organic: carbon-containing
• biosignature: possible life sign
• seismometer: quake listener
• canals: dug waterways
• lakebed: old lake floor