Finding a Faraway Planet: teacher key

Aliens and UFOs, grade 5 edition, written for 5th grade. Scientists search Mars with robots and other stars with telescopes. They also check strange lights in the sky.

Read the book. Print this page for the key.

Questions and answers

1. What is a transit?
   • A planet passing in front of its star (answer)
   • A robot driving on Mars
   • A strange light in the sky
2. What makes Mars look red?
   • High heat
   • Rusty iron in its ground (answer)
   • Red water
3. What do the shapes of old river valleys and lakebeds suggest?
   • Mars was always dry
   • Rovers dug them
   • Water most likely once flowed there (answer)
4. What do some Mars rovers look for, as of November 2026?
   • Signs tiny living things could have lived there (answer)
   • A way home
   • Alien ships
5. What does UFO stand for?
   • Unknown fast orbit
   • Unidentified flying object (answer)
   • Under the floor of Omaha
6. What does the habitable zone describe?
   • Where rovers land
   • Where meteors fall
   • Where a planet could have liquid water (answer)

Words

• transit: planet crossing
• habitable: fit to live
• exoplanet: far-off planet
• deltas: river fans
• meteors: shooting stars