New Google game is a fun way to learn about the moon cycle

If you landed on Google’s homepage yesterday, you would have noticed that there was a fun card game where you put cute cards together and learn about the moon cycle. This is the name for how the moon’s appearance changes during a month, or more specifically, the 29.5 days of its orbit around Earth.

The cycle goes from New Moon to New Moon and is used in many calendars, especially in religious ceremonies, from Christianity and Judaism to Islam and Hinduism. The Lunar New Year, celebrated in China and many Asian countries, comes from a lunar calendar related to the phases of the moon.

Why does the moon have phases?

The moon is neatly locked with our planet, meaning it always shows the same face – what we call the near side. The other face is the other side, not the dark side – we’re about to see the entire moon eventually get sunlight.

As it orbits the Earth, the moon is at different angles to the sun. At the Full Moon, our satellite is approximately behind the Earth and in the opposite direction from the Sun, meaning the near side is fully illuminated. But then, about 14 days later, there is a New Moon, when the Moon is in the same direction as the Sun, so the far side is fully illuminated and the near side is in shadow.

Basically, the phases are the portion of the moon’s near side that is covered by the moon’s own shadow. It’s the same on Earth. When we are in the shadow of the Earth, we simply call it night.

The phases are not related to lunar eclipses, where the moon passes through the Earth’s shadow. They don’t happen every month because the moon’s orbit is tilted compared to Earth’s orbit around the sun. Eclipses only occur when the Sun, Earth and Moon are on the same alignment – the alignment is called syzygia. They can occur two to five times a year.

What are the moon phases?

We start with the New Moon, when the near side is completely dark. Over the next week, the moon will be in a crescent – ​​a shape that has become synonymous with the moon itself. Crescent comes from the word crescere – Latin for ‘to grow’ – but is now used for the shape. The crescent after New Moon is a waxing crescent.

You can tell from the direction of the horns whether the crescent is getting bigger or smaller. If they point east, it increases; if they point west, it decreases. If you don’t know your East from your West, don’t worry. In the Northern Hemisphere, the crescent increases in size when it is to the right of the moon. In the Southern Hemisphere, the moon appears upside down, so the crescent is on the left.

Next we come to the Half Moon, also known as the First Quarter, about a week after the New Moon. While the crescent moon is usually visible during the day until sunset, the First Quarter extends into the early night. To reach most of the night, we need the waxing moon.

This brings us to the Full Moon, two weeks after the New Moon, when the Moon is fully illuminated. And then the waning phase begins, a mirror image of the waxing process that goes through a waning moon, the last quarter, the waning crescent and finally the new moon.