A Cold Red Desert: teacher key

Mars, grade 4 edition, written for 4th grade. Mars is a cold, dry desert world with giant landforms and two lumpy moons. Robots from Earth have driven and flown there.

Read the book. Print this page for the key.

Questions and answers

1. Which spacecraft was the first American spacecraft to land safely on Mars?
   • Viking 1 (answer)
   • Sojourner
   • Ingenuity
2. How long is a year on Mars?
   • 687 Earth days (answer)
   • 365 Earth days
   • 24 hours 40 minutes
3. Mars is about half the width of Earth. A map of Earth shows it 20 centimeters across. How wide would Mars be on the same map?
   • About 40 centimeters
   • About 10 centimeters (answer)
   • About 20 centimeters
4. What is the air on Mars mostly made of?
   • Oxygen
   • Water vapor
   • Carbon dioxide (answer)
5. What does sol mean?
   • A day on Mars (answer)
   • A moon of Mars
   • A Mars rover

Words

• sol: a Mars day
• gravity: a pull
• lumpy: not round
• rover: a robot car
• lander: a landing craft