Question

Which two moons are also called half moon ?
A) First Quarter and Third Quarter
B) Waning Crescent and Waxing Crescent
C) Waxing Crescent and First Quarter
D) Full and New Moon

Answer 1

Hint: The different shapes of the moon which are visible at different times of the month are called the phases of the moon. The moon has eight major phases at different times throughout the month. We can easily solve the question by understanding what happens in each phase of the moon.

Complete step by step solution:
The first quarter is the first half moon of a lunar month. In the first quarter, one half of the moon is illuminated. It is known as the first quarter as the moon travels about a quarter of the way around the earth since the new moon. It appears in the sky after the waxing crescent and before the waxing gibbous. The third quarter is commonly known as the half moon. When the opposite half of the moon is illuminated it is known as the third quarter. It appears after waning gibbous and before the waning crescent.

Hence, Option (A) is the correct option.

The waxing gibbous is that phase of the moon in which the area of illumination of the lunar surface continues to increase. During the waxing gibbous phase more than half of the moon’s surface appears to be illuminated by the sun. It appears in the night sky before the full moon and after the first quarter.

The full moon appears in the night sky when the moon is 180 degrees away from the sun and is as close to the earth as it can be while being fully illuminated by the sunlight from our perspective. It appears in the night sky after the waxing gibbous and before the waxing gibbous.

Note: The eight phases of moon are as follows:
New moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter and finally the waning crescent.
The Moon takes $$27.3$$ days to orbit Earth, but the lunar phase cycle (from new Moon to new Moon) is $$29.5$$ days. The Moon spends the extra $$2.2$$ days "catching up" because Earth travels about $$45$$ million miles around the Sun during the time the Moon completes one orbit around Earth.