Seeing into the moon

This exercise is a part of Educator Guide: Rover Peers Beneath Moon’s Farside / View Guide

Directions for teachers: After your students read “Rover peers beneath moon’s farside,” ask them to answer the following questions.

1. What is Chang’e-4 and what makes it unique?

Chang’e-4 is a Chinese spacecraft that landed on the moon. It is the first spacecraft to land on the farside of the moon.

2. What type of spacecraft is Yutu-2, and how is it different from Chang’e-4?

Yutu-2 is a rover, which means it can travel across the moon’s surface. Chang’e-4 is a lander — it is stationary and cannot explore the moon’s surface beyond where it landed.

3. What technology does Yutu-2 use to explore the moon?  Are there limitations to Yutu-2’s technology? Explain.

The rover used radar to collect data on material under the moon’s surface. Yes, a limitation of the rover’s radar is that it can probe only to a depth of 40 meters.

4. Based on the diagram, what did Yutu-2 find? Be as specific as possible with your description.

Over a distance of about 106 meters, the rover found three distinct layers of material — a top layer of fine soil that extended 12 meters below the surface, a middle layer of coarse material mixed with large rocks that extended 12 meters below the top layer and a bottom layer extending 26 meters below the middle layer. The bottom layer had areas of both fine and coarse materials.

5. What inferences did scientists make based on the finding?

Scientists think the bottom two layers were created from many meteorites and other objects smashing into the moon and displacing material. The top layer of fine soil probably resulted from micrometeorite impacts and temperature shifts. Overall, the layers suggest the farside had a violent history.

6. The author refers to the moon’s farside as a layer cake. What type of literary device is this, and why do you think the author uses it?

This is an example of a metaphor. The author likely used this literary device to help readers visualize the farside’s distinct layers.

7. What does geologist Daniel Moriarty say is a big question in lunar science? What leads scientists to ask this question?
Moriarty says that a big question is why the moon’s nearside and farside look so different.
The moon’s nearside has a relatively smooth surface, while its farside is marked with more craters.

8. Were there terms in the story that were new to you? Can you come up with definitions for these terms based on the story?

The terms regolith and ejecta were unfamiliar. Regolith is fine soil. Ejecta is material that is flung away (or ejected), in this case when objects slam into the moon.