Earth, Moon, and Sun Lesson 2.6: Critical Juncture Assessment

A student astronomer went outside and made two observations of the Moon that were several days apart. Her observations are shown in the diagram above. The light part of the Moon appeared to get smaller over time. Why did this happen?

• Between the first observation and the second observation, the Moon moved farther away from the sun so less sunlight reached the Moon’s surface.

• Between the first observation and the second observation, Earth moved so its shadow was blocking more of the Moon so the student astronomer was able to see less of it.

• Between the first observation and the second observation, the Moon rotated so that less of the light-colored rock on the Moon’s surface faced Earth.

• Between the first observation and the second observation, the Moon moved so that the student astronomer was able to see less of the half that faces the sun.

How many moons does earth have

• 2
• 5
• 9
• 1

The complete cycle of the moon lasts about a _.

• day
• year
• week
• month

Omi stood outside her house and made two observations of the Moon that were several days apart. Her observations are shown in the diagram above. The light part of the Moon appeared to get larger over time. Why did this happen?

• Between the first observation and the second observation, the Moon moved so that Omi was able to see more of the half that faces the sun.

• Between the first observation and the second observation, the Moon moved closer to the sun so more sunlight reached the Moon’s surface.

• Between the first observation and the second observation, the Moon rotated so that more of the light-colored rock on the Moon’s surface faced Earth.

• Between the first observation and the second observation, Earth moved so its shadow was blocking less of the Moon so Omi was able to see more of it.

How many suns do we have

• 13
• 21
• 1
• 4

Which moon phase is when you can't see the moon at all?

• Waning crescent
• Full moon
• Waxing gibbous
• New moon

What is the correct order of the moon phases?

• new, full, 1st quarter, 3rd quarter
• new moon, 1st quarter, full moon, 3rd quarter
• 1st quarter, 3rd quarter, new moon, full moon
• new, 1st quarter, 3rd quarter, full

How much of the moon is always lit?

• can't tell
• always changes
• half
• 3/4

After observing the Moon over several nights, students noticed that the illuminated portion of the Moon was getting smaller each night. What is the most likely reason for this change?

• The Moon was spinning faster, causing less sunlight to reflect off its surface.

• The Moon was moving so that less of the half facing the sun was visible from Earth.

• The Moon was moving farther from the sun, so less sunlight reached it.

• Earth was moving so that its shadow covered more of the Moon each night.

How many stars are in our solar system?

• billions

• hundreds

• two

• one