Question

A student observed the moon on Tuesday. She drew a picture of its shape in her journal, as shown below. Approximately how long will the student have to wait until she can see the moon in its same shape and position again?

A) 7 days
B) 14 days
C) 28 days
D) 30 days

Answer 1

The student will have to wait approximately 29.5 days to see the moon in the same phase again, which corresponds to the lunar cycle or synodic period. Therefore, the closest answer would be C) 28 days.

Step-by-step explanation:

To understand the lunar cycle, it's essential to know that the moon completes its orbit around Earth in approximately 27.3 days which is known as its sidereal period. However, the cycle that we observe from Earth, where the moon goes through all its phases, from a new moon to a full moon and back to a new moon, takes about 29.5 days. This is called the synodic period. Since the question implies observing the moon return to its same shape observed on a Tuesday, we are discussing the synodic period. To experience a complete lunar cycle and see the moon in the same phase again, the student would have to wait approximately 29.5 days. Therefore, the answer is C) 28 days, as it is the closest whole number to the actual synodic period, rounded down.