The following activity can be done over the course of one day, one week, or even a month (if you would like to create your very own lunar calendar, example below).
What you need:
- Oreos
- A spoon or a plastic knife
- Access to a view of the moon
Optional:
- A camera to take photos
- Access to the website: www.timeanddate.com/moon/phases
- The website can be useful for those of you who are looking to create a lunar calendar and need to recreate moon phases in advance
The point of the activity is to represent the various phases of the moon using delicious Oreo cookies! While the shape of our moon doesn’t change, the shape that we see in the sky varies depending on the current phase of the moon.
If there is a full moon, meaning the illuminated part of the moon appears as a full circle, separate one Oreo cookie and put the biscuit without any cream to the side (you can eat it or use it for baking purposes). The biscuit with all of the cream doesn’t need to be changed, because the cream represents the parts of the moon that we can see.
If there is exactly half of the moon showing, and the part of the moon that you can see (illuminated) is on the right side, this is the moon in its “first quarter”.
In this case, you will separate an Oreo cookie and put the biscuit without any cream to the side. You will be working with the biscuit with the cream on it. Here, to represent the first quarter phase of the moon, you will use your spoon to remove the cream from the left side of the biscuit. What remains is cream on the right side, again representing the part of the moon you can see.
If there is exactly half of the moon showing, and the part of the moon that you can see (illuminated) is on the left side, this is the moon in its “third quarter” (also called the “last quarter”).
Similarly to how you represented the moon in its first quarter, you will use your spoon to remove/shape the cream on the biscuit to represent what you see in the sky.
The new moon phase occurs when the illuminated part of the moon is facing away from the earth. In this case to represent the new moon, you will take off all of the cream from the biscuit after separating the cookie or simply use the other biscuit from the cookie to represent this phase.
There are other “in between phases”: the waxing gibbous, the waxing crescent, the waning crescent, the waning gibbous.
This activity can be done daily in order to represent the current moon in the sky, or you can use the website www.timeanddate.com/moon/phases to check in advance how the moon will look on the days of the week or the month coming up. In this way, you can create your calendar in advance. Use the camera to take pictures of your cookies and put them together to create your very own lunar calendar!
Fun discussion facts:
Ask your child: Why does the moon have phases? What is the role of the earth? What is the role of the sun?
The moon is the earth’s only natural satellite. Some other planets have many natural satellites, for example Jupiter has over 50 “moons” or natural satellites! If ever you get confused about what the moon will look like the next day, what you see on the right side of the moon is what there will be more of on the next night. Therefore, if the right side of the moon is illuminated one night, the moon will continue to become more illuminate the coming days. If the right side of the moon isn’t visible (in the shadows), the moon will continue to become less visible in the coming days.
