Reading: Phases of the Moon

What is the duration of a complete cycle of the Moon's phases, known as a lunation?

• 20 days

• 27-29.5 days

• 30 days

• 31 days

During which phase is the Moon completely invisible from Earth, except during a solar eclipse?

• New Moon

• Full Moon

• First Quarter

• Waning Crescent

What phenomenon allows us to see slightly more of the Moon's surface than would otherwise be visible?

• Libration

• Earthshine

• Eclipse

• Tidal Locking

Which phase of the Moon occurs when more than half of the Moon is illuminated, but it is not yet fully illuminated?

• Waxing Gibbous

• Waning Gibbous

• First Quarter

• Last Quarter

What is the effect called when sunlight reflects off Earth's surface onto the Moon, illuminating the darkened area of the Moon's nearside?

• Earthshine

• Libration

• Solar Reflection

• Moonlight