Book 8 activities
Try it at home: 150 science activities from Book 8
Every question in A Million Whys Book 8, The Space Expedition, ends with a "Think like a scientist" idea. Here they are in one place. Each one links to its question page, with the video and the full answer.
Expedition 1: Night Sky & Stars (25)
1. Why Can You See Only a Few Thousand Stars with Just Your Eyes?
Hold your fist at arm’s length and count the stars inside it. Try again from a darker spot.
2. Why Are Some Stars Brighter than Others?
Pick the three brightest stars tonight and sketch their triangle.
3. Why Is the Night Sky Dark If There Are So Many Stars?
Cover a flashlight with pinholes and shine it on a wall , tiny lights, dark gaps.
4. Why Do So Many Star Names, Like Altair and Aldebaran, Start with “Al-”?
With a grown-up, look up three star names and find out what each one means.
Do this with a grown-up5. Why Do Astronomers Agree on 88 Official Constellations?
Invent a new constellation from five stars and give it a silly name.
6. Why Do the Moon and Planets Follow the Same Path Across the Sky?
On a clear evening, spot the Moon and a bright planet and sketch the imaginary line that joins them.
7. Why Can’t You See Stars During the Day?
With a grown-up, look for the pale Moon in the daytime sky. Never look anywhere near the Sun.
Do this with a grown-up8. Why Can You See Different Constellations in Winter than in Summer?
On a clear night in each season, use a sky map app with a grown-up to name two constellations you can see.
Do this with a grown-up9. Why Is the Milky Way a Pale Band?
On a dark night away from city lights, hunt for the Milky Way’s glow.
10. Why Do City Lights Hide the Stars?
Compare stars from a bright street with stars from a darker park (with a grown-up).
Do this with a grown-up11. Why Do Different Cultures See Different Pictures in the Same Stars?
Pick four stars from a sky photo, connect them, and invent your own story about the shape.
12. Why Do Stars Have Different Colors?
Find one reddish star and one bluish-white star tonight.
13. Why Do We Say Starlight Is Old Light?
If light takes 4 years to reach us from Proxima Centauri, in what year did it leave?
14. Why Do Some ‘Stars’ Move Across the Sky in Minutes?
Spot a slow, steady satellite trail after sunset (grown-up help).
Do this with a grown-up15. Why Does the Big Dipper Help Find the North Star?
Use the Dipper pointers to find Polaris tonight.
16. Why Does the North Star Barely Seem to Move?
Take a long-exposure photo with a grown-up to see star trails circling.
Do this with a grown-up17. Why Do Southern Skies Show Different Stars?
Look up the Southern Cross , a famous southern landmark.
18. Why Do Star Clusters Look Like Glitter Piles?
Find the Pleiades (‘Seven Sisters’) on a clear autumn or winter night.
19. Why Do Nebulae Look Like Colorful Clouds?
Search a library book or NASA image of the Orion Nebula.
20. Why Will Some Stars Someday Become Supernovas?
List three things that needed star explosions: iron in blood, calcium in bones, oxygen.
21. Why Do Binary Stars Orbit Each Other?
Imagine double sunsets , sketch a planet with two suns.
22. Why Are Black Holes Hard to See, and How Do We Find Them?
Draw a black hole as a dark dot with a bright swirl of hot gas around it, like the pictures astronomers make.
23. Why Do Galaxies Look Like Spirals, Ovals, or Blobs?
Find pictures of spiral and elliptical galaxies and spot the difference.
24. Why Does a Nearby Star Seem to Jump When Earth Moves?
Hold up a thumb at arm’s length. Close one eye, then the other, and watch it jump against the background. That’s parallax!
25. Why Do People Still Stare at Stars with Just Their Eyes?
Spend five quiet minutes star-spotting with no screen light.
Expedition 2: Moon & Earth Dance (25)
26. Why Does the Moon Look Upside Down in Australia?
Look at a photo of the Moon, then turn it upside down. That’s the view from the Southern Hemisphere!
27. Why Is There a New Moon You Can’t See?
Mark new Moon on a calendar and notice darker starry nights.
28. Why Does a Full Moon Look So Round and Bright?
Compare full-Moon brightness with a crescent night.
29. Why Does the Moon Seem to Follow Your Car?
On your next ride, buckled in, watch the Moon and a nearby tree. Which one seems to move more?
30. Why Does the Moon Rise and Set?
Note moonrise time tonight; check tomorrow , it shifts.
31. Why Does Moonrise Time Change Each Day?
Track moonrise for three evenings and subtract the times.
32. Why Are There Two High Tides a Day, Not One?
Look up today’s high-tide times for a nearby coast or bay and see if there are two.
33. Why Are Some Tides Especially High (Spring Tides)?
Compare tide charts at full Moon and at quarter Moon.
34. Why Do Bright Streaks Spray Out From a Few Spots on the Moon?
With a grown-up, look at a full Moon through binoculars and find the bright rays near the bottom.
Do this with a grown-up35. Why Can You Sometimes See the Dark Part of a Crescent Moon?
Spot earthshine on a thin crescent , the ‘old Moon in the new Moon’s arms.’
36. Why Do Lunar Eclipses Turn the Moon Reddish?
Mark the next lunar eclipse date on your calendar.
37. Why Are Solar Eclipses Rarer to See From Your Town?
Never look at the Sun without certified eclipse glasses. Ask a grown-up to check yours.
Do this with a grown-up38. Why Does the Moon Have Craters?
With a grown-up, use binoculars to scan the Moon for big dark ‘seas’ and bright crater rays.
Do this with a grown-up39. Why Are There Dark Patches on the Moon?
Sketch the Man-in-the-Moon pattern from the dark maria.
40. Why Is Moon Dust So Clingy for Astronauts?
Compare smooth beach sand with crushed crackers: one is round, one is jagged.
41. Why Is There Almost No Weather on the Moon?
List three Earth weather things the Moon can’t have.
42. Why Does Daylight on the Moon Last About Two Earth Weeks?
If you camped on the Moon, about how many Earth sleeps would one lunar daytime last?
43. Why Did Apollo Astronauts Bounce When They Walked?
Hop on Earth, then imagine the same hop six times floatier.
44. Why Does the Moon Help Keep Earth’s Tilt Steadier?
Ask how seasons might go wild without a big moon.
45. Why Can the Moon Occult (Cover) a Star or Planet?
Watch for Moon-near-planet nights on a sky calendar.
46. Why Do Calendars Sometimes Have a ‘Blue Moon’?
Check if this year has a Blue Moon month.
47. Why Does the Moon Look Bright If Its Rock Is as Dark as Old Pavement?
In a dim room, shine a flashlight on white paper and on dark gray paper. Which one reflects more light?
48. Why Is the Moon Slowly Drifting Away From Earth?
Measure 3.8 centimeters on a ruler. That’s how far the Moon moves away in one year.
49. Why Did People Once Think the Moon Made People ‘Loony’?
Interview a grown-up about Moon myths they heard as kids.
Do this with a grown-up50. Why Do Future Explorers Still Want to Return to the Moon?
Design a one-page Moon base: power, air, food, fun.
Expedition 3: Sun & Planets (25)
51. Why Is the Sun a Star, Not a Planet?
Write three labels: the Sun is a star, Earth is a planet, the Moon is a moon.
52. Why Does the Sun's Middle Spin Faster than Its Top and Bottom?
Spin a paper plate with a sticker near the middle and one near the edge. They turn together because the plate is solid, which the Sun is not.
53. Why Must You Never Stare at the Sun?
Learn one safe Sun-viewing method: certified eclipse glasses, or a pinhole projector where you look at the paper, never at the Sun.
54. Why Are Planet Orbits Ovals, Not Perfect Circles?
With a grown-up, press two pins into cardboard, loop string around them, and trace an oval with a pencil, keeping the string tight.
Do this with a grown-up55. Why Is Mercury So Extremely Hot and Cold?
Compare Mercury’s day/night temps in a kids’ space book.
56. Why Is Venus Hotter than Mercury Even Farther Out?
With a grown-up, put one thermometer inside a lidded jar and one beside it, both in the sun. Compare them after 15 minutes. Never use a parked car , it gets dangerously hot!
Do this with a grown-up57. Why Is Earth Called the Goldilocks Planet?
Name three Earth features life loves: water, air, energy.
58. Why Does the Red Planet Have Blue Sunsets?
Find a rover photo of a Martian sunset and compare its colors with an Earth sunset.
59. Why Do Mars Rovers Need Tough Wheels and Brains?
Design a rover: what tool would you add , scoop, camera, or weather station?
60. Why Is Jupiter a Gas Giant?
Trace a coin for Earth, then draw Jupiter 11 coins wide.
61. Why Does Jupiter Have a Great Red Spot?
Hunt a recent Jupiter image showing the Red Spot.
62. Why Does Titan, One of Saturn's Moons, Have Thick Orange Air?
With a grown-up, look up photos of Titan’s orange haze and describe its color.
Do this with a grown-up63. Why Does Neptune Have the Fastest Winds in the Solar System?
With a grown-up, find a photo of Neptune’s Great Dark Spot and describe how it looked.
Do this with a grown-up64. Why Are Uranus and Neptune Called Ice Giants?
Sort the eight planets into rocky, gas giant, and ice giant groups.
65. Why Does Uranus Roll on Its Side?
Tip a globe on its side and imagine a pole facing the Sun for decades.
66. Why Is Pluto Now Called a Dwarf Planet?
Debate: should ‘planet’ mean something different? Write two sentences.
67. Why Do Some Planets Have Dozens of Moons?
Draw Jupiter with its four biggest moons: Io, Europa, Ganymede, and Callisto.
68. Why Is the Asteroid Belt Between Mars and Jupiter?
Name one famous asteroid: Ceres (also a dwarf planet!).
69. Why Do Inner Planets Take Less Time to Orbit the Sun?
Rank planets by year length from memory, then check.
70. Why Will the Sun Keep Shining for Billions of Years?
Draw a timeline of the Sun’s life: its birth, today, and about five billion years from now.
71. Why Is a Day on Venus Longer than Its Year?
Write Venus’s day (243 Earth days) and year (225 Earth days) side by side. Which is longer?
72. Why Do Planets Sometimes Look Like They Go Backward?
Outside with a friend: you walk a small circle quickly while they walk a bigger circle slowly around you. Watch them against faraway trees as you pass. They seem to go backward!
Do this with a grown-up73. Why Is the Sun’s Surface Speckled with Sunspots?
With a grown-up, find a NASA photo of the Sun from today and count the sunspots. Never look at the real Sun.
Do this with a grown-up74. Why Does Solar Wind Shape a Huge Bubble Around the Planets?
Draw the Sun, the planets, and the giant bubble around them. Label the solar wind and Earth’s magnetic shield.
75. Why Do Scientists Still Discover New Small Worlds?
Search ‘Kuiper Belt object’ discoveries from recent years.
Expedition 4: Rockets, Satellites & Astronauts (25)
76. Why Do Rockets Turn and Roll Shortly After Liftoff?
Hold a pencil like a rocket and show a roll, a pitch, and a yaw with your hand.
77. Why Do Rockets Drop Stages as They Climb?
Build a paper two-stage straw rocket and watch the handoff idea.
78. Why Do Rockets Rise Slowly at First and Then Speed Up?
Watch a launch video with a grown-up and time how long the rocket takes to clear the tower.
Do this with a grown-up79. Why Do Astronauts on the Space Station See About 16 Sunrises a Day?
Divide the minutes in a day, 1,440, by 90 to count how many orbits the station makes.
80. Why Do Astronauts Grow a Little Taller in Space?
Measure your height right after waking and again at bedtime. Gravity squeezes you a little during the day!
81. Why Do Satellites Stay Up Without Flapping Wings?
Draw Earth and a circular path hugging it.
82. Why Are Communications Satellites Often Parked High Above the Equator?
Find a satellite dish and note which way it points.
83. Why Do GPS Satellites Need Einstein's Help?
Open a maps app outside (on a grown-up’s phone) and watch the blue dot settle.
Do this with a grown-up84. Why Does the International Space Station Need Constant Boosts?
Track ISS passes at spotthestation.nasa.gov with a grown-up.
Do this with a grown-up85. Why Do Astronauts Exercise Every Day in Space?
Do 20 careful squats , feel the gravity workout astronauts miss.
86. Why Is Space Food Sticky or Packed in Pouches?
Try eating a tortilla instead of crumbly bread , astronaut favorite.
87. Why Do Launches Pause for Weather Sometimes?
Watch a launch webcast and listen for weather ‘go/no-go.’
88. Why Do Heat Shields Glow on the Way Home?
Quickly pump a bike tire a few times with a grown-up, then feel the warm pump. Squeezed air heats up!
Do this with a grown-up89. Why Do Space Toilets Use Air Flow, Not Water Swirls?
Imagine brushing teeth with a swallow-or-towel rule , water floats!
90. Why Do Astronauts Sleep in Sleeping Bags Clipped to Walls?
Try reading while lying on your side, then on your back. Orientation feels different.
91. Why Are Clean Rooms Used Before Launch?
Wear a hairnet for a snack prep , tiny clean-room vibe.
92. Why Do Mission Control Teams Work in Shifts?
Design a 3-shift schedule for a pretend mission day.
93. Why Do Spacewalkers Tether Themselves?
Climb a playground structure using three-point contact: two hands and one foot, or two feet and one hand (grown-up nearby).
Do this with a grown-up94. Why Do Rockets Launch Toward the East Often?
Gently toss a soft ball straight up while walking slowly (outside, grown-up nearby). It keeps your forward motion, just like a rocket keeps Earth’s eastward spin.
Do this with a grown-up95. Why Are Reusable Rockets a Big Deal?
Compare a disposable cup with a washable mug. That’s reuse thinking.
96. Why Do Cubesats Hitch Rides to Space?
Invent a cubesat mission in one sentence.
97. Why Is Radio Delay a Problem Toward Mars?
Time a 20-minute wait , that’s a possible one-way Mars lag.
98. Why Do Astronauts Train Underwater?
Float carefully in a pool with a grown-up , notice slow turns.
Do this with a grown-up99. Why Do Spacecraft Need Many Computers and Backups?
List backups you use: spare pencil, extra batteries, second flashlight.
100. Why Would a Trip to Mars Take Months?
Write a packing list for a 500-day Mars crew (food, fun, fixes).
Expedition 5: Space Rocks, Comets & Looking for Life (25)
101. Why Do Some Meteors Blaze Into Fireballs?
With a grown-up, look up a recent fireball report and note its time and direction.
Do this with a grown-up102. Why Are Meteor Showers Named After Constellations?
Find when the Perseids or Geminids peak this year.
103. Why Do Some Meteorites Make Craters on Earth?
Visit a museum meteorite (or photo) and note the fusion crust.
104. Why Do Some Comets Glow Green?
With a grown-up, look at photos of a bright comet and find the green head, blue tail, and white tail.
Do this with a grown-up105. Why Does a Comet Move Fastest When It Passes Nearest the Sun?
Roll a marble down a ramp and notice that it moves fastest at the bottom, just as a comet does near the Sun.
106. Why Do Asteroids and Comets Matter for Earth’s History?
Read about the Chicxulub impact and dinosaurs (age-appropriate).
107. Why Do Scientists Sample Asteroids with Spacecraft?
Name a mission: OSIRIS-REx or Hayabusa2.
108. Why Is Liquid Water a Big Deal When Hunting Life?
List places with water clues: Mars, Europa, Enceladus.
109. Why Might Icy Moons Hide Oceans?
Bend a paper clip back and forth ten times, then touch the bend. Flexing makes heat!
110. Why Do Europa and Enceladus Excite Astrobiologists?
Compare Europa, a moon of Jupiter, with Enceladus, a moon of Saturn.
111. Why Haven’t We Found Definite Alien Life Yet?
Invent a fair rule: what evidence would convince you?
112. Why Can Astronomers Find Planets They Can’t See?
Dim a flashlight with a marble pass , transit demo.
113. Why Is the Habitable Zone Different Around Other Stars?
If a star is cooler than the Sun, should life-friendly planets hug closer?
114. Why Do SETI Projects Listen for Radio Signals?
Discuss: should Earth announce itself loudly? Why or why not?
115. Why Is Mars’s Methane a Curious Clue?
Name two methane sources on Earth: cows/microbes and some rocks.
116. Why Do Biosignatures Need Careful Checking?
Make a ‘life checklist’ with three must-have clues.
117. Why Clean Spacecraft Before Visiting Ocean Worlds?
Wash hands before a ‘sample’ snack experiment , clean science habit.
118. Why Are Extremophiles on Earth Important for Space Biology?
Find one extremophile example: tardigrades or hot-spring bacteria.
119. Why Do Meteor Showers Feel Safer than Asteroid Movies?
Learn what NASA’s planetary defense teams monitor.
120. Why Do Comets Have Nuclei That Look Dark and Lumpy?
Browse a Rosetta mission photo of comet 67P.
121. Why Collect Antarctic Meteorites?
Why are dark rocks easier to spot on white ice?
122. Why Might Organic Molecules Arrive From Space?
Separate ‘building blocks’ from ‘living cells’ in a sentence.
123. Why Do Dust Tails of Comets Sometimes Cause Meteor Showers Later?
Match a shower name to its parent comet, such as the Perseids and comet Swift-Tuttle.
Do this with a grown-up124. Why Map Near-Earth Asteroids?
Check a reputable ‘asteroid close approach’ list with a grown-up.
Do this with a grown-up125. Why Keep Asking If We’re Alone?
Write your own ‘Are we alone?’ hypothesis in two lines.
Expedition 6: Telescopes & Sky Detectives (25)
126. Why Do Big Telescopes Use Mirrors Instead of Lenses?
Look at yourself in the inside of a shiny spoon. It flips your image like a telescope mirror.
127. Why Are Many Top Telescopes on Mountains?
Name a famous peak observatory: Maunakea or Canaries.
128. Why Put Telescopes in Space?
Find one Hubble Deep Field image , galaxies galore.
129. Why Does JWST See in Infrared?
With a grown-up, point a TV remote at a phone camera and press a button. Many cameras show the invisible infrared light as a purple glow.
Do this with a grown-up130. Why Do Radio Telescopes Look Like Giant Dishes?
Listen to a recorded pulsar ‘beat’ online with a grown-up.
Do this with a grown-up131. Why Do Astronomers Use Filters and Many Wavelengths?
Compare a galaxy in visible light and in X-ray images.
132. Why Can Adaptive Optics Cancel the Twinkle of Our Air?
From a safe sidewalk with a grown-up, look at a faraway object across the shimmer over sunny pavement.
Do this with a grown-up133. Why Do Star Parties Share Telescopes?
Find a local astronomy club event (grown-up plan).
Do this with a grown-up134. Why Do Astronomers Write Down the Date, Time, and Place of Every Sighting?
Start a one-week sky log with date, time, place, sky clarity from 1 to 5, and one sketch.
135. Why Do Planetarium Shows Help Even If They’re Not the Real Sky?
Visit a planetarium or watch a reputable virtual sky tour.
136. Why Do Your Eyes Need 20 Minutes to See the Stars Well?
With a grown-up nearby, stay outside in the dark for 20 minutes without screens and notice how many more stars appear. Use a red flashlight if you need light.
Do this with a grown-up137. Why Do Apps Help , But Eyes Still Matter?
Identify one bright planet with an app, then look unaided.
138. Why Do Spectroscopy Rainbows Reveal Star Recipes?
Look at a fluorescent light through diffraction glasses, a rainbow-glasses toy.
139. Why Do Citizen Scientists Help Real Missions?
Try a Zooniverse astronomy project with a grown-up.
Do this with a grown-up140. Why Measure the Sky in Magnitudes?
Venus can reach magnitude minus 4, while a faint star you can just see is magnitude 5. Which is brighter?
141. Why Do Many Telescopes Sit Inside Domes with a Slot That Opens?
Draw a dome with a sliding slot and show with arrows how it turns toward a star.
142. Why Are Binoculars a Great First ‘Telescope’?
Try 7×50 or 10×50 binoculars on the Moon (steady arms or tripod). Never point binoculars or telescopes at the Sun , it can blind you.
143. Why Align a Finderscope Before Hunting Planets?
Daytime practice: aim a finder at a distant chimney (never the Sun).
144. Why Do Some Images Use False Color?
Read an image caption: which filters made the colors?
145. Why Collaborate Across Countries on Big Telescopes?
Name one international project: Event Horizon Telescope or JWST partners.
146. Why Can a Solar Storm Bother Satellites and Power Grids?
With a grown-up, check today’s space weather forecast and see whether auroras are likely.
Do this with a grown-up147. Why Teach Kids to Question Viral ‘Planet’ Photos?
Reverse-search one dramatic space image with a grown-up.
Do this with a grown-up148. Why Do Light Pollution Laws and Dark-Sky Parks Help?
Suggest one shielded outdoor light improvement at home.
149. Why Is Patience Part of Astronomy?
Plan a backup indoor space activity for cloudy evenings.
150. Why Does Every Space Answer Lead to a New Question?
Write one space question you can’t answer yet. With a grown-up, hunt for its answer this week.
Do this with a grown-up