Let’s learn about the moon

It’s our constant companion, and influences life on Earth in ways big and small

This is a picture of the moon taken from the International Space Station on January 29, 2021.

NASA

The moon is more than a bright, beautiful orb in the night sky. Our nearest neighbor also plays a big part in making the Earth a good place to live. Located an average of only 384,400 kilometers (238,855 miles) away, it’s got enough gravity to help stabilize the Earth on its axis. That makes our planet’s climate more stable than it would be otherwise. The moon’s gravity also pulls the oceans back and forth, producing tides.

As the moon orbits the Earth, it passes through different phases. They are the result of sunlight reflecting off the moon, and where the moon is in relation to the Earth. During a full moon, we see one entire half of the moon lit by the sun because the Earth is between the moon and the sun. During the new moon, none of the moon is visible and the sky is exceptionally dark. That’s because the moon is between the Earth and the sun, and only the dark side of the moon faces our planet.

The moon cycles through all its phases once every 27 days. This is also the amount of time it takes to go around the Earth. As a result, the same side of the moon always faces the Earth. The far side of the moon was a mystery until people developed spacecraft. Now that far side is a bit less of an unknown. China has even landed a spacecraft on this far side of the moon, to learn more about it.

The moon’s light and its effect on the tides are important to animals here on Earth. Some animals time their breeding with the tides. Others change their feeding to stay safe from lions when the moon is dark. And deep in the Arctic night, the moon can provide some illusive illumination for living things.

Want to know more? We’ve got some stories to get you started:

The moon has power over animals: The moon is known for its tidal effects. But its light also can exert a powerful influence on animals large and small. (11/7/2019) Readability: 8.0

There’s water on sunny parts of the moon, scientists confirm: The new observations were made by a telescope on board a jet in Earth’s atmosphere. They confirm the presence of water on sunlit areas of the moon. (11/24/2020) Readability: 7.8

Welcome to moon rock central: A Science News reporter’s visit to NASA’s moon-rock lab shows the hyper-pristine conditions in which these rocks are kept — and why that’s so important. (9/5/2019) Readability: 7.3

Take a tour of the moon with this video from NASA. Some of the moon’s craters haven’t seen sunlight in two billion years!

Explore more

Scientists Say: Exomoon

Does the moon influence people?

This high-tech sweeper is designed for super-clingy moon dust

Astronauts may be able to make cement with their own pee

Wiggly wheels might help rovers plow through loose lunar soils

Rover finds ‘layer cake’ below ground on moon’s farside

Learning from what Apollo astronauts left on the moon

Preserving remnants of human culture on the moon

Activities

Word find

Blast off! One of the problems with getting to the moon is that we need to bring so much stuff. How do engineers design rockets to carry heavy payloads? This NASA activity will show students what engineers have to think about when trying to take objects (and people) to space.

Bethany Brookshire was a longtime staff writer at Science News Explores and is the author of the book Pests: How Humans Create Animal Villains. She has a Ph.D. in physiology and pharmacology and likes to write about neuroscience, biology, climate and more. She thinks Porgs are an invasive species.