Galaxy Jar Experiment- Super Fun Space Activity for Kids!

Every kid loves the galaxy. There is something completely fascinating about space, spaceships, space travel, and how things work in space. Explore all of these themes when learning how to make a galaxy jar experiment! It’s a fun way to explore galaxy science experiments right at home or in the classroom. 

While this isn’t precisely a science experiment for kids, you can use it to explore scientific concepts of space, the universe, galaxies, and nebula! Use this activity to learn about space and the galaxy this summer.

Make this summer a science summer! Keep reading to learn about galaxies and some STEAM extensions you can do to make this activity more educational!

How to Make a Galaxy Jar

Follow along with these directions to learn how to make your own galaxy jar experiment. It’s a fun space-themed STEAM activity that most kids will have a blast making!

Galaxy Facts for Kids

If you’re doing this galaxy jar experiment, you might like learning these galaxy facts!

What is a Galaxy?

A galaxy is a collection of billions of stars, solar systems, gas, and dust. According to NASA, galaxies are HUGE. Unimaginably huge.

Galaxies also have black holes at the center (at least all of the large ones that we’ve observed so far do). This is why you’ll often find that galaxies form a spiral pattern around a central point, as if they are in the process of getting sucked into the world’s slowest drain.

Our galaxy is called the Milky Way because of it’s cloudy appearance. Even though we often see galaxies that have brilliant, super-saturated colors, most of these images have been enhanced to make them stand out more.

How Many Galaxies Are There?

There are more galaxies than we have been able to count. The Hubble Space Telescope (which my grandfather helped launch into space and that will forever be the coolest thing about me) observed just one tiny patch of space for 12 days and found over 10,000 galaxies just in that small section.

Some scientists estimate that there are over a hundred billion galaxies, which is about one galaxy for every dollar that Jeff Bezos owns.

What Does a Galaxy Look Like?

Since we haven’t seen all hundred billion galaxies, we can’t say for sure what they all look like. But we have observed several galaxy shapes, which include:

• Spiral shapes (the Milky Way is a spiral galaxy)
• Elliptical shapes (Cygnus A, a galaxy located 600 million lightyears away, is elliptical shaped)
• Blob shapes (although this may just be because they are too far away to observe properly. Lyman-alpha blob LAB-1 is the largest galaxy we’ve observed in space and is 11.5 billion lightyears away)

What Color are Galaxies?

The truth is, we don’t really know what color space is! We do know that things in space emit a wide range of light wavelengths. Some of them, like red and blue light we can see, but space also has a bunch of UV light, X-ray light, and gamma ray light, which human’s can’t see. But maybe other creatures in the universe can!

The main space telescope operating today is the Hubble Space Telescope. It takes pictures in black and white.

Scientists then enhance those images with color to help them find things that would be hard to see in a black and white photo.

So, yes, space pictures are dyed and colored, and it looks really cool, and maybe they aren’t accurate images for what a human would see if they were there in space, but there are a lot of light waves that humans can’t see, and who knows, space may be brilliantly colored after all, we just can’t take it all in with our human eyes.

Galaxy Jar STEM Extensions

Expand on the galaxy jar experiment by adding these STEM elements to your experiment.

Science: Learn about how galaxies form, how many galaxies exist, and what planets are in our Milky Way galaxy.

Technology: Learn about how astronauts and scientists track happenings in space.

Engineering: Discuss ways to make the jar more durable. Using other materials, protecting the glass, etc.

Math: Calculate the distance between planets, between galaxies, and how long it would take to get outside of the Milky Way.

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What You Need for Your Galaxy Jar Experiment

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• Coarse grit sandpaper
• Fusion paint (optional)
• Acrylic paint
• Small battery-operated tea lights
• Acrylic paint sealer
• Paintbrushes

Directions for the Galaxy Jar Experiment

Making a galaxy jar is easy.

If you have the ability, roughen up the jar either by sanding it a bit with rough-grit sandpaper or you can use fusion paint. You can also just be extremely careful not to scratch the paint and seal it later.

First, paint the jar black. You’ll probably need 2 coats of paint to get it thick enough.

Let each coat of paint dry for about 10 minutes before adding another or else you’ll just end up pulling the first coat off with the new paint.

Once the base coat is dry, dab on a mixture of colors to make the galaxy “clouds” or nebula. We used purple, pink, and dark blue.

Once the nebula are dry, use dots of white paint to make stars and planets.

After the entire jar is dry, add a sealer top coat to protect the jar from scratches.

Drop in a battery-operated tea light to use your galaxy jar as a candle or light source. The jar light will emit a faint glow and look really cool in a bathroom or bedroom.

More Galaxy Science Experiments

Galaxy Sugar Crystals

Galaxy Oobleck Science Experiment

DIY Galaxy Slime

Space Printables for Kids

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