Dadscamp
Solar System Walk
Three activities to walk the planets, feel the scale of space, and discover what makes each world unique.
← → or swipe to navigate • Based on data from the original planning doc
Overview
A scale-model solar system walk for Dadscamp — three activities that let you walk the planets and feel the vastness of space.
Running Around
Race the planets — walk orbits at scaled speeds. Mercury laps you 4× while Neptune barely moves.
Distance of Mercury
Sun=basketball. Where's Mercury? A grain of sand 10m away. Neptune? A blueberry 772m out.
Path Installation
Hanging tags along a campsite trail — planet names, distances, light-times, and wow-facts.
⏱️ Time needed: 45–60 min for the walk; 30 min setup
Scale: 1 metre = ~6 million km. Neptune at 155m. Sun is a golf ball (4.8 cm).
What to Bring
Clive
- 🖨️ Print 8 planets + Moon
- 📏 Walk tax tape (measuring tape)
- 🌾 Flour (for marking positions)
- 🔭 Telescope
Joe
- 📱 Phone holder, tripod, mic stand
- 🎾 Tennis ball (Sun prop)
- 🏀 Basketball (Sun at Mercury-scale)
- 🟤 Gafa tape (gaffer tape)
- ⚾ Some planets to scale
Extra Props
- 🏌️ Golf ball — spray-paint yellow/orange (≈ Sun at true scale)
- 🏓 Ping-pong balls on sticks/headbands — walker planets
- 🌱 Poppy seed, peppercorn, dried bean — true-size exhibit tray
- 🛞 Small hula hoop / paper plate — Saturn's rings
- 🏖️ Yellow beach ball — bigger Sun-holder prop
- 📇 A5 cards on tent pegs — name + wow-fact per planet
- 🧵 Pre-knotted string at planet distances — fastest setup
Activity 1: Running Around
Walk the scaled orbital circumference of each planet at the right proportional speed. Mercury = you at a light jog; Neptune = one step every couple of seconds.
How it works
- Mark the Sun at centre. Each planet has a scaled orbital radius (from distance table).
- Benchmark: run the Mercury circle at full speed — that's "Mercury speed."
- Outer planets walk slower: Venus = 0.74× Mercury, Earth = 0.59×, etc.
- Clap every ~2 seconds = 1 Earth year passing.
- Timelapse tip: film 2–5 min, speed up 10–30×. Mercury blurs, Earth ticks, Jupiter barely moves.
"The outer solar system is so vast and slow that on any human timescale it's basically frozen."
Activity 1: Orbital Radii
| Object | Full Scale | Half (m) | Quarter (m) |
|---|---|---|---|
| Sun | — | — | — |
| Mercury | 2.0 m | 1.00 | 0.50 |
| Venus | 3.74 m | 1.87 | 0.94 |
| Earth | 5.17 m | 2.59 | 1.29 |
| Mars | 7.87 m | 3.94 | 1.97 |
| Jupiter | 26.9 m | 13.45 | 6.73 |
| Saturn | 49.5 m | 24.75 | 12.38 |
| Uranus | 99.2 m | 49.60 | 24.80 |
| Neptune | 155.3 m | 77.65 | 38.83 |
Half and quarter scales shrink the field if you don't have 155m clear. Even at quarter, Neptune is 39m out.
Activity 1: Walk Speeds & Claps
| Planet | Radius (m) | Circumference | Walk speed | Claps to orbit |
|---|---|---|---|---|
| Mercury | 1.00 | 6.3 m | 1.59 m/s | ~4 |
| Venus | 1.87 | 11.7 m | 1.18 m/s | ~10 |
| Earth | 2.59 | 16.3 m | 1.00 m/s | ~16 |
| Mars | 3.94 | 24.8 m | 0.81 m/s | ~31 |
| Jupiter | 13.45 | 84.5 m | 0.44 m/s | ~192 (3m 12s) |
| Saturn | 24.75 | 155.5 m | 0.33 m/s | ~471 (7m 51s) |
| Uranus | 49.60 | 311.6 m | 0.23 m/s | ~1,355 (22m 35s) |
| Neptune | 77.65 | 487.8 m | 0.18 m/s | ~2,710 (45m 10s) |
Claps every ~2 seconds (clap = 1 Earth year passing). Mercury's done in 4 claps; Neptune takes 45 minutes.
Activity 1: Relative Speeds
"I'm moving at X × my inner neighbour / Y × my outer neighbour"
| Planet | × Inner Neighbour | × Outer Neighbour |
|---|---|---|
| Mercury | — | 1.35× Venus |
| Venus | 0.74× Mercury | 1.18× Earth |
| Earth | 0.85× Venus | 1.23× Mars |
| Mars | 0.81× Earth | 1.84× Jupiter |
| Jupiter | 0.54× Mars | 1.33× Saturn |
| Saturn | 0.75× Jupiter | 1.43× Uranus |
| Uranus | 0.70× Saturn | 1.28× Neptune |
| Neptune | 0.78× Uranus | — |
Activity 2: Distance of Mercury
Sun = a basketball (24 cm). Where's Mercury? A grain of sand 10 metres away. Neptune? A blueberry 772 metres out.
The game
- Show everyone the basketball: "This is the Sun."
- Ask: "Where do you think Mercury is? Jupiter? Neptune?"
- Walk to each scaled distance. Reveal the prop (grain of sand, cherry tomato, blueberry).
- By Jupiter (134m) the Sun-basketball is a dot. By Neptune (772m) it's barely visible.
- At each stop: say one wow-fact and the light-travel time from the Sun.
💡 Pacing tip: An adult stride is ~0.75 m, a long step ~1 m. Mercury = 13 paces. Neptune = ~1,030 paces. Pre-knotted string is fastest.
Activity 2: Basketball-Scale Data
| Object | Scaled Diameter | Scaled Distance |
|---|---|---|
| Sun | 24 cm / 9.4" (basketball) | — |
| Mercury | 0.84 mm (grain of sand) | 10 m |
| Venus | 2.1 mm (sesame seed) | 19 m |
| Earth | 2.2 mm (peppercorn) | 26 m |
| Moon | 0.6 mm | orbits Earth at 6.6 cm |
| Mars | 1.2 mm (coarse sand) | 39 m |
| Jupiter | 2.4 cm (cherry tomato) | 134 m |
| Saturn | 2.0 cm (grape) | 246 m |
| Uranus | 8.7 mm (blueberry) | 493 m |
| Neptune | 8.5 mm (blueberry) | 772 m |
| Pluto | 0.4 mm (fine dust) | over 1 km |
At this scale, Earth–Sun light-travel time (8 min) maps to walking 26m at ~5 cm/s — appropriately slow.
Activity 3: Path Installation
Hanging tags along a campsite path — planet names, distances, light-times, and wow-facts. Leave it up all weekend.
What to hang
- 📇 Tags at eye level from trees
- 📍 Planet name + distance from Sun (real km)
- 📏 Scale distance + one wow-fact
- ⏱️ Light-travel time (Mercury 3 min, Earth 8 min, Jupiter 43 min, Neptune 4 hr)
Setup tips
- 🎗️ Different coloured ribbons per planet
- 🔄 Use doubled scale (300m) for the trail — more rewarding spacing
- 🧩 String + text + planter ribbon
- 🪨 Weight tags with stones if windy
🏆 Why this works: Kids keep finding/re-finding tags all weekend. Light-times give a more visceral "size of the solar system" hit than km.
Activity 3: Path Scale Reference
Size-to-scale at each distance. Use these for the hanging tags — the Sun's a golf ball, everything else is tiny.
| Object | Distance | Size to Scale |
|---|---|---|
| Sun | — | 48.1 mm (golf ball) |
| Mercury | 2.0 m | 0.17 mm |
| Venus | 3.74 m | 0.42 mm |
| Earth | 5.17 m | 0.44 mm |
| Mars | 7.87 m | 0.23 mm |
| Jupiter | 26.9 m | 4.83 mm |
| Saturn | 49.5 m | 4.02 mm |
| Uranus | 99.2 m | 1.75 mm |
| Neptune | 155.3 m | 1.70 mm |
Farthest object is 153m away, Sun 4.8cm across. All planets are sub-millimetre apart from Jupiter and Saturn. Doubling the scale (Neptune at 300m) still makes Earth only 1cm.
Real Orbital Speeds (Normalised)
Orbital speeds relative to Earth's casual walk (≈ 1 m/s). Use these to pace each planet's "year."
| Planet | Speed vs Earth | What that looks like |
|---|---|---|
| Mercury | 1.59× | Light jog (~5.7 km/h) |
| Venus | 1.18× | Brisk walk |
| Earth | 1.00× | Normal walk |
| Mars | 0.81× | Relaxed stroll |
| Jupiter | 0.44× | Slow amble — half-pace |
| Saturn | 0.33× | Very slow stroll |
| Uranus | 0.23× | Tai-chi pace |
| Neptune | 0.18× | Barely moving — one step every couple of seconds |
The punchline: If Earth's circle takes ~30s to walk, in that same 30s — Mercury laps you ~4×, Mars does ½ a lap, Jupiter shuffles ~13m, Neptune takes ½ a step.
Running the Activities
Making it fun
- 🧠 Guess-first: Line everyone up. "Where's Mars? Jupiter?" People cluster planets too close. Watch jaws drop walking to Neptune.
- 🚶 The Long Walk to Neptune: Walk together Sun→Neptune, stopping at each. Look back at the Sun (golf ball) — by Jupiter it's a dot, by Neptune barely visible.
- ⏱️ Light-speed race: Light takes 8 min Sun→Earth. At scale, light "walks" 5.17m in ~8 min of scaled time.
- 🌑 Asteroid belt: Kids between Mars and Jupiter throwing pinecones gently in a circle.
- 🏃 Role assignment by stamina: Neptune = dad with a folding chair. Mercury = kids who want to run.
- 🏁 Year-race: "Who completes their year first?" Mercury wins in seconds. Jupiter gets bored. That's the point.
Before the day
- 📏 Field: Need 160m clear minimum, ideally 200m. Pace it.
- 💨 Wind: Ping-pong balls and paper signs need pegging. Stones in cups.
- ☀️ Sun position: Put it at a memorable landmark (tree, gate).
- 📱 Timelapse: Tripod or wedged on a bench. 2–5 min at 10–30× speed.
☀️ Fun Facts: The Sun
A million Earths would fit inside it.
Light takes ~100,000 years to escape the core, then 8 minutes to reach Earth.
It's a ball of plasma — a fourth state of matter, not solid/liquid/gas.
Loses 4 million tonnes of mass every second turning hydrogen into helium and light.
Middle-aged star — halfway through its 10-billion-year life.
🔥 Parker Solar Probe: fastest human-made object, ~700,000 km/h skimming the corona. Crosses the US in 20 seconds.
🔥 The corona is millions of degrees vs surface ~5,500°C — tiny "campfire" magnetic reconnection events heat it.
🔥 Currently near solar maximum (late 2024–2025) — insane aurorae visible from southern England, France, even Mexico.
☿️ Fun Facts: Mercury
A day on Mercury (sunrise→sunrise) lasts two Mercury years. The day is longer than the year.
No atmosphere. +430°C in sunlight to –180°C in shade — biggest temp swing in the solar system.
It's shrinking — the core is cooling, leaving wrinkly cliffs across the surface.
Despite being closest to the Sun, Venus is hotter.
Has ice at the poles, in craters that never see sunlight.
☄️ Has a comet-like tail — stream of sodium atoms millions of km long, blown back by solar wind.
🫀 Core is freakishly oversized — ~85% of the planet by radius. Got smacked early on, lost most of its mantle.
🛰️ BepiColombo (ESA/JAXA) is flybying now, entering orbit late 2026.
♀️ Fun Facts: Venus
Hottest planet: 465°C — hot enough to melt lead.
Rains sulfuric acid (boils off before hitting the ground).
Spins backwards. A Venus day is longer than a Venus year.
Surface pressure is 90× Earth's — like being 900m underwater.
Brightest object in our sky after Sun and Moon — the 'morning/evening star.'
🧪 Phosphine found in clouds in 2020 — possible biosignature. Still contested, new measurements keep finding it.
🛰️ DAVINCI (NASA) and EnVision (ESA) launching late this decade — first dedicated Venus missions in 30+ years.
🏙️ Sweet spot ~50km up where pressure and temp are Earth-like. Cloud cities = serious colonisation proposal.
🌍 Fun Facts: Earth
The only planet not named after a god.
71% covered in liquid water. We've mapped more of Mars than our own ocean floor.
The Moon moves away at 3.8 cm/year — about as fast as fingernails grow.
We're moving at ~107,000 km/h around the Sun, and the whole solar system moves at 800,000 km/h around the galaxy.
Earth's core is roughly the same temperature as the Sun's surface (~5,500°C).
🌙 Moon has water ice at the south pole confirmed. Artemis is going there. Water = fuel = stepping stone to Mars.
🌙 Earth has temporary "minimoons" every few years — 2024 PT5 was one.
🌙 Inner core may have stopped rotating around 2009 and started reversing. Published 2023, still controversial.
♂️ Fun Facts: Mars
Olympus Mons: biggest volcano in the solar system — 22 km tall, 3× Everest, as wide as France.
Valles Marineris: 4,000 km long canyon. The Grand Canyon is a side ditch.
Sunsets on Mars are blue (dust scatters light differently).
Two lumpy moons, Phobos and Deimos — probably captured asteroids. Phobos will crash into Mars in ~50M years.
Used to have rivers, lakes, probably an ocean. Dried-up shorelines are still visible.
💧 Liquid water might exist deep underground (2024 InSight data suggests a reservoir 11–20 km down).
🧪 Perseverance has cached rock samples on the ground, waiting for Mars Sample Return (budget ballooning, being redesigned).
🚁 Ingenuity made 72 flights before crashing in early 2024 — proved powered flight in 1% atmosphere.
🕷️ "Spiders" at the south pole: CO₂ ice heated from below explodes through the surface every spring.
♃ Fun Facts: Jupiter
Could swallow every other planet combined. 2.5× the mass of everything else (except the Sun).
Great Red Spot: storm bigger than Earth, raging for at least 350 years.
95 known moons. Ganymede is bigger than Mercury.
Europa has a liquid water ocean under ice — twice Earth's ocean water. Best bet for life in the solar system.
Failed star: if 80× more massive, fusion would've ignited — we'd have two suns.
🫥 Juno revealed a "fuzzy" core — diluted, smeared-out heavy elements. Rewrites gas giant formation theory.
🪐 Magnetic field generates the most powerful aurorae in the solar system, driven by its own rotation + moon Io.
🛰️ Europa Clipper launched October 2024, arriving 2030. Carries a message with "water" in 103 languages.
🌋 Io is the most volcanically active body — lakes of molten rock, Loki Patera a lava lake the size of Wales.
♄ Fun Facts: Saturn
Would float in water if you had a big enough bathtub — less dense than water.
Rings are 99.9% pure water ice, only ~10 metres thick. From the side they disappear.
146 known moons — most of any planet.
Titan has rivers, lakes and rain — of liquid methane. Only other place with surface liquid.
Hexagonal storm at the north pole, 30,000 km across. Nobody fully knows why it's a hexagon.
💍 Saturn is LOSING its rings. 10,000 kg/second raining into the planet. Gone in ~100 million years. We're alive at a privileged moment.
💍 Cassini found "ring rain" of organic compounds and water falling into the atmosphere — way more than expected.
💧 Enceladus shoots plumes of water from its south pole with organic molecules, phosphorus. JWST found a plume 10,000 km long.
🚁 Dragonfly (NASA) launches 2028 — a nuclear-powered drone that will fly around Titan.
⛢ Fun Facts: Uranus
Tipped on its side — axis at 98°. Rolls around the Sun like a barrel. Hit by something Earth-sized long ago.
Each pole gets 42 years of sunlight then 42 years of darkness.
Visible to the naked eye but so slow and faint nobody noticed it was a planet until 1781.
Smells like rotten eggs — atmosphere full of hydrogen sulfide.
Coldest planet atmosphere: –224°C. Colder than Neptune despite being closer to the Sun.
💎 It rains diamonds. High-pressure carbon in the mantle compresses into diamond rain.
🛰️ 2023 US Decadal Survey ranked Uranus orbiter as TOP priority for next big mission. Only Voyager 2 flyby (1986) ever.
🛰️ 2024 reanalysis of Voyager 2 data: the flyby happened during a freak solar wind event. Our textbook understanding may be wrong.
🧊 JWST resolved Uranus's rings in infrared — stunning detail, new faint rings. Interior may have superionic ice — a new state of matter.
♆ Fun Facts: Neptune
Fastest winds in the solar system: 2,100 km/h — faster than the speed of sound on Earth.
A year on Neptune is 165 Earth years. It's completed only one orbit since its discovery in 1846.
Also rains diamonds.
Discovered by maths before anyone saw it — astronomers worked out Uranus's wobble.
Moon Triton orbits backwards, slowly spiralling in. Will be torn apart → ring system bigger than Saturn's.
🔭 JWST's first Neptune images (2022) showed rings clearly for first time since 1989 — they're back, plus new bands.
🌑 Dark spots come and go on a scale of years. JWST caught one with a bright companion cloud. Unknown why they form.
🌋 Triton has active cryovolcanoes spitting nitrogen — plumes 8 km tall. Captured Kuiper Belt object, basically Pluto's sibling.
☀️ From Neptune, the Sun is 900× dimmer than from Earth — looks like a very bright star, not a sun.
🌌 Beyond / Wow-Tier
If you flew to the Sun at jet speed (900 km/h)
It'd take you ~19 years.
Pluto
Sunlight takes 5½ hours to reach it. From Pluto, the Sun looks like a bright star.
The solar system is mostly empty
If the Sun were a golf ball at the centre of your field, the nearest other star would be a golf ball in Australia.
JWST has imaged exoplanets directly
Actual photographs of planets orbiting other stars. Possible dimethyl sulfide detected on K2-18b — a biosignature 124 light-years away.
The "Planet Nine" hypothesis
A hidden planet 5–10× Earth's mass at hundreds of AU. Vera Rubin Observatory is searching.
Interstellar visitor 3I/ATLAS (2025)
Only the third confirmed object from outside our solar system. Largest and oldest of the three.