Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
The Moon does not produce its own light; it reflects light from the Sun ().
The Moon orbits the Earth in a circular path, completing one full revolution in approximately days.
The different shapes of the Moon we see from Earth are called 'Phases'. These phases depend on the relative positions of the Sun, Earth, and Moon.
There are primary phases in the lunar cycle: New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Third Quarter, and Waning Crescent.
Waxing means the illuminated (lit) portion is increasing, while Waning means the illuminated portion is decreasing.
The New Moon occurs when the Moon is located between the Earth and the Sun, resulting in visibility of the lit side from Earth.
📐Formulae
💡Examples
Problem 1:
If a Full Moon is observed on the of the month, approximately when will the next New Moon occur?
Solution:
Around the or of the month.
Explanation:
The time between a Full Moon and a New Moon is half of a lunar cycle. Since a full cycle is days, half a cycle is days.
Problem 2:
A student observes that the Moon is getting 'bigger' (more lit up) every night. Is the Moon 'Waxing' or 'Waning'?
Solution:
The Moon is Waxing.
Explanation:
In astronomy, 'Waxing' refers to the period where the visible surface of the Moon increases from (New Moon) to (Full Moon).
Problem 3:
How many main phases are counted in one complete lunar orbit?
Solution:
phases.
Explanation:
The cycle is divided into distinct stages based on the amount of sunlight reflected toward Earth: New Moon, Waxing Crescent, Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Quarter, and Waning Crescent.