The lunar phase that occurs one week after the first quarter is :
It takes about 4 weeks for the moon to complete its cycle of phases. After every 1 week the moon undergoes one quarter (1/4) of its phase/cycle. Therefore the primary lunar phase that the moon will undergo one week after the first quarter is the Third quarter phase before the full moon
During the third quarter phase, half of the moon is completely illuminated in comparison to the other half ( first quarter ). this phase is the last phase before the full moon.
Hence we can conclude that The lunar phase that occurs one week after the first quarter is : Third quarter phase.
Learn more about Lunar phases : https://brainly.com/question/13538936
