Beyond the surface
The Atmosphere
Journey up through the layers of air — from the clouds above your head to the edge of space and beyond.
Interactive
Climb through the sky
Every layer stacked from the ground to space. Tap a band to dive into its secrets, and see how everyday heights compare on the journey to orbit.
🌍 Ground level · sea level
Journey to space
How high is high? A climb from the tallest mountain all the way to the Moon.
The Moon
Earth’s natural companion.
Geostationary orbit
Satellites that hover over one spot.
GPS satellites
Beam navigation signals worldwide.
Hubble Telescope
Peers deep into the universe.
Space Station (ISS)
Orbits Earth about every 90 minutes.
Auroras
Northern & Southern Lights glow here.
Kármán line
The official edge of space.
Noctilucent clouds
The highest clouds on Earth.
Weather balloon
Burst altitude of high-altitude balloons.
Ozone layer
Shields life from ultraviolet rays.
Cruising airliner
Jets cruise near the top of the troposphere.
Mount Everest summit
The highest point on land.
The five layers + space
Layers of the atmosphere
Each layer behaves differently — in temperature, thickness and what lives or flies there. Tap any card for the full story.
Reading the sky
Types of clouds
Almost every cloud forms in the troposphere, the layer we live in — except the rare noctilucent clouds, which drift far higher in the mesosphere. Meteorologists sort them by the height of their base into high, middle and low clouds, plus the towering storm clouds that stretch through them all.
High clouds
Thin, wispy and icy — made of ice crystals high in the cold upper troposphere.
Cirrus
"curl of hair"
Delicate, feathery white streaks swept across a blue sky by high winds.
Did you know? Cirrus clouds are made entirely of ice crystals and often signal a change in weather within a day.
Cirrocumulus
"curl" + "heap"
Tiny white ripples in neat rows, often called a "mackerel sky".
Did you know? Sailors read a mackerel sky as a sign that unsettled weather is on the way.
Cirrostratus
"curl" + "layer"
A thin, milky veil that covers the whole sky and can create a halo around the Sun or Moon.
Did you know? The glowing ring, or halo, is sunlight bending through millions of ice crystals.
Middle clouds
Grey-and-white decks of water droplets and some ice, sitting in the middle troposphere.
Altocumulus
"high" + "heap"
Patchy white-and-grey cloudlets arranged in rounded clumps or rolls.
Did you know? Altocumulus on a warm, humid morning can warn of thunderstorms later that day.
Altostratus
"high" + "layer"
A grey or blue-grey sheet covering the sky, with the Sun showing faintly as if through frosted glass.
Did you know? It often thickens and lowers into nimbostratus just before steady rain.
Nimbostratus
"rain" + "layer"
A thick, dark, featureless layer that brings long periods of steady rain or snow.
Did you know? Nimbostratus blots out the Sun completely — "nimbus" is Latin for rain-bearing cloud.
Low clouds
The clouds closest to the ground — mostly water droplets, and often the greyest.
Stratus
"layer"
A low, uniform grey blanket that can bring drizzle and mist, like fog that has lifted off the ground.
Did you know? When stratus touches the ground, we simply call it fog.
Stratocumulus
"layer" + "heap"
Low, lumpy grey-and-white patches that cover much of the sky in rolls or rounded masses.
Did you know? It is the most common cloud type on Earth, seen almost everywhere.
Cumulus
"heap"
The classic fluffy "cotton-wool" clouds with flat bases and bright, cauliflower tops on fair days.
Did you know? A single fair-weather cumulus can weigh hundreds of tonnes in water droplets.
Towering storm clouds
Vertical giants that grow through the whole troposphere and unleash the fiercest weather.
Cumulonimbus
"heap" + "rain"
The towering thunderstorm cloud, with an anvil-shaped top, bringing heavy rain, lightning, hail and even tornadoes.
Did you know? A big cumulonimbus can tower over 12 km high — taller than Mount Everest stacked on itself.
Special & highest clouds
Rare and unusual clouds — including the highest clouds on Earth, far above the weather.
Noctilucent
"night-shining"
Electric-blue, shimmering clouds in the mesosphere, about 80 km up — the highest clouds in the world.
Did you know? They glow after sunset because they are so high they still catch sunlight long after the ground is dark.
Lenticular
"lens-shaped"
Smooth, saucer-like clouds that form over mountains and are often mistaken for UFOs.
Did you know? They stay almost still, hovering in place even in strong winds.
Mammatus
"udder-shaped"
Pouch-like bulges hanging beneath a storm cloud, a sign of powerful turbulence.
Did you know? They usually appear after the worst of a thunderstorm has passed.
What air is made of
The air we breathe
The atmosphere is a mix of gases that has stayed remarkably balanced for millions of years.
Dry air is overwhelmingly nitrogen and oxygen. The amount of water vapour varies from almost none over deserts to around 4% in the steamy tropics.
Did you know?
Amazing atmosphere facts
The atmosphere has no hard edge — it simply thins out until it blends into space, so the 100 km Kármán line is an agreed boundary rather than a physical wall.
More than half of all the air by weight lies below 5.5 km — roughly the height of the base camps on the world’s tallest mountains.
Without the greenhouse effect of our atmosphere, Earth’s average temperature would be about −18 °C instead of a comfortable +15 °C.
The sky is blue because air molecules scatter the Sun’s blue light more than its red light.
Air pressure at the top of Mount Everest is only about one-third of that at sea level, which is why climbers carry oxygen.
The ozone layer is surprisingly thin — if squeezed to sea-level pressure it would be only about 3 mm thick.
The atmosphere protects us from roughly 25 million meteoroids that enter it every single day.
Sound cannot travel in the near-vacuum above the atmosphere — which is why space is completely silent.