During an occultation or "covering up" of neptune by the moon, an astronomer measures the angular 's speed as it that it takes the moon's edgc 4 seconds to cover neptune completely. etimat size of neptune as seen from earth. hint: you need to calculate the moon "moves" on the celestial sphere a. 1 are second b. 2 are seconds c. 5 arc seconds d. 10 arc seconds e. 45 arc seconds