Make five headings: star, planet, dwarf planet, moon, small Solar System body.
Place Sun, Earth, Neptune, Pluto, Moon, an asteroid, and a comet under headings.
Write one reason for every placement. Make an “I need more evidence” box for an unknown object.
Invent a clue for one object and ask a partner to classify it.
Think, draw, explain
Can an object be important even if it is not a planet?
What evidence would help classify an unfamiliar object?
Grown-up guide & possible answers
Sun: star. Earth and Neptune: planets. Pluto: dwarf planet. Moon: moon. Asteroid and comet: small bodies.
Importance is not a classification rule. Observations of orbit, shape, composition, and surrounding objects help classification; a name or color alone is insufficient.
Write two hypotheses: “closest always means hottest” and “atmospheres can change temperature.”
Draw Mercury near the Sun and Venus a little farther out. Give Venus a thick atmosphere label and Mercury a very thin exosphere label.
Read the Mercury and Venus cards. Circle which hypothesis the comparison supports.
Write a short evidence-based explanation for a younger explorer.
Think, draw, explain
Which world has the hotter surface overall?
What else, besides distance, should a temperature explanation consider?
Grown-up guide & possible answers
Venus has the hotter surface overall despite being farther from the Sun than Mercury.
Atmospheric composition and the greenhouse effect matter. This comparison disproves the simple claim that distance alone determines surface temperature.
25 minutes · Low-power flashlight · Two different-size balls · Paper · An adult helper
Your investigation
Indoors, ask an adult to aim a low-power flashlight away from eyes. Use it only as a pretend Sun.
Arrange flashlight, small Moon ball, and larger Earth ball in a line. Find where the Moon ball’s shadow falls.
Switch to flashlight, Earth ball, Moon ball. Sketch where Earth’s shadow falls.
Move the Moon ball above the line and note why the shadow misses. Mark all diagrams “not to scale.”
Think, draw, explain
Which object is in the middle for a solar eclipse?
Why does a full Moon not cause an eclipse every month?
Grown-up guide & possible answers
For a solar eclipse the Moon lies between the Sun and Earth. For a lunar eclipse Earth lies between the Sun and Moon.
The Moon’s orbit is tilted, so most monthly alignments miss the necessary shadow path. This is an indoor geometry activity, not instructions for looking at the Sun.
20 minutes · Paper · Pencil · A round lid for tracing, optional
Your investigation
Draw one circle-like orbit and one very stretched oval. Put a pretend Sun near the center of the circle and off-center inside the oval.
Draw arrows to show a traveler’s direction and label each line as a guide, not a physical rail.
Write two limitations of your model, including that most planetary orbits are only mildly oval.
Add a sentence about gravity bending a moving object’s path.
Think, draw, explain
Are real orbit lines glowing tracks in space?
Does an orbiting planet need a road beneath it?
Grown-up guide & possible answers
No. Lines in an explorer or drawing are visual aids showing a path.
No. Gravity and the object’s motion produce an orbit. A drawing simplifies three-dimensional positions and should not be mistaken for a physical structure.
20 minutes · Paper · Pencil · Calculator, optional
Your investigation
Pretend a luggage scale reads 6, 12, and 18 units on Earth for three different bags.
Use the classroom approximation that Moon surface weight is one-sixth of Earth surface weight. Calculate each Moon reading.
Draw the same bag on both worlds and label its mass as unchanged.
Write what a weaker gravity field changes, and what it does not.
Think, draw, explain
What are the three Moon readings?
Would the bag contain fewer things on the Moon?
Grown-up guide & possible answers
The approximate Moon readings are 1, 2, and 3 weight units.
No. The contents and mass stay the same. Local gravity changes weight; the one-sixth factor is a rounded comparison, not a precise value for every location.
25 minutes · Squared paper or a drawn 6-by-6 grid · Pencil
Your investigation
Label grid columns A–F and rows 1–6. Start at A1; mark rock targets B3 and E5, and blocked steep slopes C3, C4, and D4.
Plan a route that reaches both targets using only up, down, left, or right moves. Do not cross blocked cells.
Count moves. At each target, write an observation you would make before collecting a sample.
Ask a partner to check your route and explain why a safer route can be better than the shortest one.
Think, draw, explain
Give one valid route visiting both targets.
What should a rover observe before sampling?
Grown-up guide & possible answers
One valid route is A1→A2→A3→B3→B2→C2→D2→E2→E3→E4→E5, taking 10 moves. Other safe routes are valid.
Examples include rock layers, grain texture, nearby terrain, and instrument measurements. A sample is more useful when its geological setting is recorded.
30 minutes · Paper · Pencil · A planet or moon knowledge card
Your investigation
Choose a destination and one question that measurements could help answer.
Decide whether a flyby, orbiter, lander, or rover suits your question. Draw and label your spacecraft.
Choose two instruments, such as a camera for terrain or a thermometer for temperature, and explain what each measures.
Add one environmental challenge and one limitation: what would your mission still not know?
Think, draw, explain
Would a surface rover be suitable for Jupiter?
What makes a scientific mission question testable?
Grown-up guide & possible answers
No. Jupiter has no solid surface suitable for driving. An orbiter or atmospheric probe would suit different questions, with demanding environmental constraints.
A testable question connects to obtainable evidence, such as comparing measured temperatures. An imaginative design should still distinguish predictions from observations.
Make two headings: observation and possible explanation.
Sort these statements: “the image shows a channel”; “water may have flowed here”; “the graph has a dip”; “a planet may have crossed the star.”
Pair each observation with its possible explanation.
Invent a different explanation for one observation and name a measurement that could help test it.
Think, draw, explain
Which statements report what was measured?
Why should scientists consider more than one explanation?
Grown-up guide & possible answers
The visible channel and graph dip are observations. Flowing water and a crossing planet are proposed explanations for those observations.
Different processes can produce similar evidence. Additional measurements help distinguish explanations; scientific confidence grows through testing rather than guessing once.
Write three goals: study a faint galaxy, inspect a nearby planet, and detect light absorbed by Earth’s air.
For each goal, list a useful property, such as a larger collecting mirror, stable pointing, or placement above the atmosphere.
Draw your observatory and label where light is collected and where it is measured.
Write a safety label: “Never point at the Sun. This drawing is not a guide to building a solar telescope.”
Think, draw, explain
Why might a larger mirror help with a faint galaxy?
Why put some telescopes in space?
Grown-up guide & possible answers
A larger collecting area can gather more light from a faint target; magnification alone does not gather extra light.
Earth’s atmosphere absorbs some wavelengths and blurs some observations. Space telescopes avoid those effects, while ground telescopes still do valuable work.