On the night of 31 August, 2023, many of us gazed at the blue moon and commented on its brilliance in the night sky. With the upcoming Mid-Autumn Festival happening on 29 September, celebrating the next full moon will be just as exciting!
The Mid-Autumn Festival (or Zhong Qiu Jie in Mandarin) is a festival to celebrate the 15th day of the eighth lunar month. Many are familiar with the cultural practices of lighting paper lanterns, eating mooncakes and telling stories about Chang-E and the Jade Rabbit. Have you ever wondered how the Mid-Autumn Festival relates to science?
“It’s Just a Phase!”: Why Does the Moon Change in a Month?
The brilliance of the Mid-Autumn full moon reminds us of how Chang-E became the Moon Goddess in Chinese folklore. However, the full moon is only one of eight recorded moon phases. As the Moon rotates around the Earth, which rotates around the Sun, the light of the Sun illuminates the Moon. The Moon that we see at night is a reflection of light off the Moon’s surface. As the Moon orbits the Earth, the amount of light from the Sun changes and creates the lunar phases that we can observe in about one month.
Light ‘Em Up: Fly Your Own Paper Lantern! [Activity]
On the night of the Mid-Autumn Festival, children may be seen carrying lit lanterns featuring colourful patterns and characters. While lanterns cannot be released into the sky in Singapore, we can make our own paper lanterns fly at home!
Lanterns are traditionally lit by a candle, which releases heat and warms the air. Hot air is less dense than cool air and will rise, causing the lantern to rise with it. For our lantern, we will use a hair dryer to heat the air.
For this activity, you will need these materials:
- Crepe paper
- Hair dryer
- Glue stick
- Markers with rounded tips [optional]
- Cut a 20cm by 10cm rectangle out of crepe paper. Repeat this step four times.
- Cut a 10cm by 10cm square out of crepe paper.
- (Optional) Draw on the crepe paper that you have cut out.
- Carefully, glue one edge of the square to the short side of one rectangle.
- Glue the longer edge of one rectangle to the longer edge of another rectangle. Repeat this step four times until all longer sides are glued.
- Glue the remaining unglued edges of the square to the short edge of each rectangle. Now your lantern is ready for flying!
- Turn on the hair dryer and point the nozzle towards the ceiling. Ask someone to hold the opening of the lantern over the nozzle.
- Once the lantern is inflated by hot air, release it and watch it fly!
While you are enjoying the full moon on the 29th of September, share your new knowledge of the Moon and why paper lanterns rise with your friends and family. Happy Mid-Autumn Festival and mooncake eating!
Written by Goh Wanling
Featured image by Zhang Yingjie