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✦ GEOGRAPHY UNIVERSE · AGES 6–11 ✦

EARTH
EXPLORER!

🌙 Orbit · Phases · Tides next door!

📖 200 Topics🆓 FREE⏱️ 5 min read🧠 Quiz included
🪨
FORMATION
Giant impact hypothesis
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🛰️
ORBIT
~27 days sidereal
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🌕
PHASES
~29.5 day cycle
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🌊
TIDES
Bulges follow Moon
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👨‍🚀
TODAY
Artemis · lasers to mirrors
🌙 THE MOON: OUR NEIGHBOUR
TOPIC 06 · GEOGRAPHY · ORBIT · PHASES · TIDES
PAGE 1 OF 5, A SILVER WORLD NEXT DOOR
NEIGHBOUR
Moon as cold airless rocky satellite orbiting close to the Earth
EARTH'S ONLY NATURAL SATELLITE
The Moon is a cold, airless ball of rock about one-quarter Earth's diameter, roughly the width of Australia, orbiting us at an average distance of about 384,000 km, close to thirty Earth-widths away. It shines by reflected sunlight, waxing and waning through a month-long pattern humans have used for calendars since prehistory. Telescopes reveal craters frozen in time; laser pulses fired from observatories still bounce off mirrors left by Apollo astronauts to measure the drift of the orbit to millimetre precision.
⚡ DID YOU KNOW?
You could fit every planet in the solar system side by side in the Earth–Moon gap, with room to spare, yet the Moon dominates our night sky because it is so close.
MOON!
SIZE
Moon size comparison showing one quarter the diameter of Earth
🌍 ~1/4 Earth diameter
⚖️ Mass ~1/81 of Earth
GAP
Average 384000 km distance gap between the Earth and the Moon
📏 ~384 000 km average
🛰️ Few days by spacecraft
PAGE 2 OF 5, TWO KINDS OF “MONTH”
ORBIT
Sidereal 27.3 day and synodic 29.5 day lunar month cycle diagram
SIDEREAL VS SYNODIC
The Moon completes one circuit relative to distant stars in about 27.3 days, the sidereal month. Yet phases repeat every ~29.5 days, the synodic month, because Earth has moved along its own orbit around the Sun, so the Moon must travel a little farther to regain the same Sun–Earth–Moon angle. Calendars that track full moons follow the synodic rhythm; satellite engineers tracking orbital planes care about sidereal numbers.
MONTH!
LOCKED
Tidally locked Moon always showing the same near face to Earth
🌗 Same face to Earth
🌊 Tides slowed rotation long ago
LIBRATION
Libration slight wobble of Moon revealing small edges of far side
↔️ Slight wobble reveals edges
🔭 Not a perfect freeze
CAPTURE?
Giant impact hypothesis with debris ring forming the Moon long ago
💥 Giant-impact model popular
🪨 Debris ring → Moon
PAGE 3 OF 5, PHASES: SUNLIGHT ON A BALL
CRESCENT
Crescent moon as a thin sunlit sliver just after new moon phase
🌒 Thin sunlit sliver
🌑 New near noon sky
GIBBOUS
Gibbous moon with more than half the face lit approaching full moon
🌔 More than half lit
🌕 Full opposite Sun
PHASE
Moon phases shown as geometry of sunlight falling on a ball in orbit
HALF THE MOON IS ALWAYS SUNLIT
From Earth we see only the hemisphere facing us combined with the Sun direction, geometry, not Earth's shadow (that is lunar eclipses, rare special cases). First quarter rises at noon; full moon rises at sunset; third quarter waits until midnight. Photographers plan “golden hour” landscapes with moonrise tables; biologists study animal behaviour tied to bright nights.
PHASE!
PAGE 4 OF 5, TIDES AND THE MOON'S PULL
TIDES
Two ocean tidal bulges chasing the Moon as Earth rotates each day
TWO BULGES CHASE THE MOON
Gravity weakens with distance, so ocean water nearest the Moon feels strongest pull and piles into a bulge while Earth's centre is pulled harder than water on the far side, leaving a second bulge opposite the Moon. Earth spins underneath, so most coastlines see two high tides per day when the rhythm matches basin geometry. When Sun and Moon align at new or full moon, spring tides run extra high; at quarter moons, neap tides moderate the swing.
TIDE!
SPRING
Spring tides with Sun and Moon aligned creating maximum tidal range
☀️ Sun + Moon combine
🌊 Extra range
NEAP
Neap tides with Sun at 90 degrees to Moon giving smaller tidal range
📐 Sun at 90° to Moon
📉 Smaller tidal range
BAY
Bay of Fundy funnel shaped coast creating dramatic surge tidal range
🌊 Fundy-style funnel shapes
⚠️ Storm surge adds on top
PAGE 5 OF 5, FOOTPRINTS, DUST AND FUTURE VISITS
APOLLO
Apollo astronauts walking on the Moon during 1969 to 1972 missions
TWELVE HUMANS WALKED HERE 1969–1972
Six crews landed in daylight equatorial zones, collecting rocks that proved ancient lava flows and giant impacts. Fine regolith clings electrostatically to spacesuits; no air means hammering heat extremes between lunar day and night. Robotic missions from many nations map ice in polar shadows today, a possible resource for breathing oxygen and rocket fuel, while NASA's Artemis programme aims to return crews with international partners for long-term science bases.
BACK!
ICE
Polar ice cold traps on Moon preserving water molecules from comets
❄️ Cold traps at poles
💧 Molecules from comets?
REMEMBER
🌙 KEY FACTS
Only natural satellite · ~27.3 d sidereal orbit · ~29.5 d phase cycle · Tidally locked face · Drives ocean tides · Airless ancient surface.
✅ Phases = Sun angle
✅ Two tidal bulges
✅ Exploration continues
🧠 QUIZ TIME!
THE MOON · 5 QUESTIONS
QUESTION 01
What does the Moon mainly orbit?
QUESTION 02
Why do we always see roughly the same side of the Moon from Earth?
QUESTION 03
Ocean tides on Earth are mainly caused by…
QUESTION 04
About how long is one complete cycle of Moon phases (new moon to new moon)?
QUESTION 05
The Moon's atmosphere is best described as…
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