Share it! Science : May the 4th Be With You: Star Wars Astronomy

May the 4th Be With You: Star Wars Astronomy

May 4th is Star Wars Day! I'm so excited to be participating in the Star Wars Day Quirky Blog Hop hosted by Witty Hoots.  Get ready for some Star Wars inspired STEM!

Have you ever wondered what our planet would be like if we had two suns like the planet Tatooine? What if we had two moons? Are the planets in the Star Wars movie realistic at all?

Let's answer those questions and have some fun with some hands-on science activities!


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2 Suns: A Tatooine Like Earth

You may have observed that Luke Skywalker's home planet, Tatooine, had two suns. Astronomers have found evidence of a planet outside of our solar system that is orbiting two stars. This planet, Kepler-16b, is part of a system much like George Lucas's fictional planet, Tatooine.

On Earth we have one sun, that provides us with light and heat. It holds our planet in orbit. It affects the seasons on Earth. How would this change if we had two suns? If Earth were like Kepler-16b we'd experience slightly colder temperatures because we'd be at a greater distance from the sun. 

Kepler-16b's suns are slightly smaller than our sun, so the pull of gravity would be less and we'd have a longer year because we'd orbit more slowly. If we had two suns the same size as our sun, then we'd have a faster orbit and a shorter year. Scientists aren't sure if a moon would form in this type of system, so our nights would be a little bit different, and the ocean tides would be affected.

Try this activity from NASA that models the rotation of Earth and the night/day cycle. You'll need a globe (or a large ball) and a flashlight. Once you've tried this out under "normal" circumstances for Earth, try it again with two suns, or in other words, two flashlights.
  • How does this change where the people on Earth are experiencing daylight?
  • Does it make the days longer or shorter?
  • What effect do you think this has on the seasons?
  • How might the human sleep cycle, or circadian rhythm be altered by having two suns? Would other animals and plants be affected too?

An Earth with 2 Moons

What would our planet be like if there were two moons rotating around it? Earth is the only planet in our solar system with just one moon. Some planets do not have any natural satellites, whereas others have dozens.

Our moon and its gravitational force gives the ocean its tides, is the reason we have a 24 hour day and it keeps the planet at the tilt that gives us seasons. The moon reflects the sunlight in the night time and we can view its phases and eclipses. How would all of this be different if we had two moons?

Night time would be brighter, which would affect nocturnal animals. Tides would be much more extreme. Our calendar, which is based on the cycle of the moon's phases (each cycle = approx. 1 month, or "moonth")

Try the "Dance of the Moon and Oceans" as a movement activity with several kids to learn about the tides. How would this movement change if there were more than one moon in this "dance"?

If you do not have a group of kids to try this with, you can learn about the tides through this video.

  • How would having two moons change how our tides work?
  • How would more extreme tides affect life on Earth?

What about the moon's phases and eclipses? Would we still see the moon the same way if there were two of them?

Try this: First, model the phases of the moon to get the hang of what is really happening up there. You can model it the way Emily Morgan, author of "Next Time You See the Moon", does it here:

Now add in another moon. You might have to find a friend to help. Experiment with where you place the moon.
  • Have the moon's phases changed?
  • How is this affecting the night sky on the Earth?
  • What if one moon were orbiting faster than the other? How would that change things?

Other Star Wars like Planets

Are there other planets that resemble the fictional ones in the Star Wars universe? Yup. But they aren't in our solar system! Exoplanet OGLE-2005-BLG-390Lb resembles the fictional cold world planet, Hoth. Mustafar, a hot molten world in Star Wars is similar to Kepler-10b and Kepler-78bKepler-22b is thought to be like the fictional ocean world, Kamino. It is also believed that there are real-life similarities out there to Princess Leia's home planet, Alderaan and to Endor, home of the Ewoks.

Still Interested? Read more:

Join us as we celebrate Star Wars Day - May 4th with some wonderful galactic inspired crafts, recipes and activity ideas!

Try this Star Wars Sensory Bin from Something 2Offer
The Jenny Evolution has some great Activity Books for All Ages
Yummy Rogue One Ice Cream recipe is a favourite from Nerdy Mamma
Share It! Science News has some fabulous Activities for Exploring Planets with 2 Suns!
Make some of these fabulous Droid Crafts from Play & Learn Everyday
These DIY Party Favours from Kidz Activities would be a hit at any party!
Mrs LeBlancs Learners are learning Star Wars in the Classroom
Defying Gravity! Sounds like great fun from Kid Minds
Make your own Airplane Fly Off like Royal Baloo!
Brush up on your galaxy sums with Daily Math from 3 Dinosaurs
KC Edventures is sharing a great Planets Math Activity
Erupting Death Star plus an I Spy Printable, some fun ideas from Little Bins
Peakle Pie shares some cute Paper Plate Ewoks


  1. Oh wow! We have learnt so much today! Thank you for joining in with the Star Wars Day Quirky Blog Hop!

    1. Excited to be a part of the blog hop! Thanks for bringing so many great posts together!

  2. My son asked me to put together a lesson on two suns. We did a few activities but nothing as comprehensive as your post. I'm looking forward to working through some of the questions you posed together with him. Thanks for inspiration!

    1. I hope that the questions are helpful and you and your son learn a lot. Another fun hands-on activity would be to build a sundial outside. Have fun!