Stuff you probably already have at home. Every one ends with the big question.
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Find your Mars weight
Mars is smaller than Earth, so its gravity pulls on you only about 38% as hard.
You need
- A bathroom scale
- Paper, pencil (or a calculator)
Steps
- Stand on the scale and write down your weight.
- Multiply it by 0.38. Example: 80 lb × 0.38 ≈ 30 lb.
- Weigh a backpack too. How heavy would it feel on Mars?
- Bonus: your mass (how much “stuff” you are) stays the same. Only the pull changes!
👨👩👧 Do it with a grown-up. Stand still on the scale, no jumping.
🔴 Will it also work on Mars? A bathroom scale uses springs and gravity. Would it read the right number on Mars, or would you need a different kind of scale?
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Soap-bubble leak finder
On Mars, people live inside sealed habitats. Outside, the air is very thin and has almost no oxygen, so even a tiny pinhole can slowly let precious air escape. Engineers on Earth find tiny leaks with soapy water!
You need
- A balloon, beach ball, or zip bag blown up with air
- A cup of water + a squirt of dish soap
- A paintbrush or sponge; a pin (grown-up only)
Steps
- Mix the soap and water.
- A grown-up pokes one teeny pinhole in the bag or ball.
- Brush soapy water all over it and squeeze gently.
- Watch for growing bubbles. That’s your leak!
- Try patching it with tape and test again.
👨👩👧 Do it with a grown-up. Grown-ups handle the pin. Keep balloons away from little kids (choking risk).
🔴 Will it also work on Mars? In a habitat, air pushes out toward the thin Martian air. Would bubbles still show the leak? What else could warn astronauts?
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Sunset in a glass
Sunlight has all colors in it. Tiny bits in Earth’s air scatter blue light the most, so the sky looks blue. At sunset, light travels through more air, the blue gets scattered away, and red-orange is left.
You need
- A clear glass or jar of water
- A few drops of milk
- A flashlight; a dark room
Steps
- Stir a few drops of milk into the water.
- Shine the flashlight through the side. Look from the side: a slight bluish glow.
- Now look through the glass straight at the light: it looks orange-yellow, like a sunset!
- Add more milk. What changes?
Mars twist: Mars’ thin air is full of fine red-orange dust, so its daytime sky looks butterscotch-orange, and its sunsets glow blue around the Sun!
👨👩👧 Do it with a grown-up. Don’t shine the flashlight into anyone’s eyes, and don’t drink the milky water.
🔴 Will it also work on Mars? What could you put in the water instead of milk to make a “Mars sky” in a glass?