Tag
Space
Planets, stars, and the dark in between — 82 tiny stories across 8 shelves.
Space
Crashy night-sky stories — 66 stories.
All space →Leftover bricks
What Are Asteroids?
Asteroids are the bricks left over from planet-building — the rubble of a world that never managed to form, mostly parked between Mars and Jupiter.
Let’s go →Not what you think
Why Do Astronauts Float?
Gravity 400 km up is still 90 per cent as strong as at your feet. Astronauts float because the station falls around Earth and never lands — and so do they.
Let’s go →Sky on fire, quietly
What Are the Northern Lights?
Earth's magnetic field turns the solar wind aside but funnels some of it down at the poles, where it lights up atoms 100 km overhead like a neon sign.
Let’s go →Three pieces of evidence
How Do We Know the Universe Had a Beginning?
Nobody watched it happen. Galaxies receding, a faint warmth in every direction, and the recipe of the gas all point back to the same hot, dense moment.
Let’s go →Gravity turned all the way up
What Is a Black Hole?
Pack matter tightly enough and escaping it would mean travelling faster than light. Nothing can, so nothing leaves — not even the light itself.
Let’s go →A dirty snowball
What Is a Comet?
The ice never melts — it goes straight from solid to gas and blasts off the surface. Halley's comes round every 76 years, so most people see it once.
Let’s go →Join the dots
What Are Constellations?
The stars in a constellation are nowhere near each other. The picture exists only from where we stand, and only for the few thousand years we are here.
Let’s go →Nothing rubs them out
Why Is the Moon Covered in Holes?
Earth is hit just as often as the Moon. The difference is that the Moon has no air, water or moving crust to rub the scars out afterwards.
Let’s go →A very old puzzle
Why Is the Night Sky Dark?
With endless stars the sky ought to blaze. It does not, because the universe has a finite age and is stretching light beyond what any eye can catch.
Let’s go →More time in the light
Why Are Days Longer in Summer?
The spin never varies — 24 hours, every day. The tilt changes how much of that spin you spend on the sunlit side, which near the poles can mean all of it.
Let’s go →A spinning Earth story
Why Day Turns Into Night
Night is not the Sun switching off. It is your side of a spinning Earth turned away from it, waiting its turn to come back round.
Let’s go →Three things in a line
What Happens in an Eclipse?
The Sun is 400 times wider than the Moon and 400 times further off, so the two look the same size — which is why a total eclipse fits exactly over it.
Let’s go →Watching for a tiny dip
How Do We Find Planets Around Other Stars?
Almost no planet round another star has been seen. They are found by the tiny, precisely repeating dip in starlight as the planet crosses in front.
Let’s go →An island of stars
What Is a Galaxy?
We see the Milky Way as a band across the sky because we are sitting inside its flat disc, looking the long way along it from out on one arm.
Let’s go →Yes, lots
Is There Gravity in Space?
Gravity never switches off, it only gets gentler with distance, and it reaches everywhere. Space is full of it — which is why everything there is orbiting.
Let’s go →Neptune, 1846
The Planet Found With a Pencil
Neptune was found by arithmetic: Uranus was being pulled off its predicted path, and the calculation said exactly where the puller must be.
Let’s go →The missing wobble
How We Proved the Earth Moves
The best argument against a moving Earth was that the stars never shifted — a good argument, until telescopes got precise enough to catch the shift.
Let’s go →Dark lines in the rainbow
How We Know What Stars Are Made Of
A philosopher called it permanently unknowable. Every element absorbs its own exact colours, so a star's rainbow spells out its ingredients.
Let’s go →The edge is not a wall
What If You Fell Into a Black Hole?
Falling into a big black hole feels like ordinary falling — while anyone watching sees you slow, redden, and freeze at the edge forever.
Let’s go →The tides are not the big one
What If We Had No Moon?
Without the Moon the tides shrink but survive, the nights go properly dark, the days get shorter — and Earth's lean starts to wander.
Let’s go →You would not notice for eight minutes
What If the Sun Went Out Tonight?
The light takes eight minutes and twenty seconds to arrive, and so would the news — after which the freeze takes days rather than seconds.
Let’s go →Three centuries of weather
Jupiter's Storm That Never Stops
Jupiter's Great Red Spot is a storm wider than Earth that has been spinning for over 300 years. There is no ground beneath it to slow it down.
Let’s go →A distance, not a time
What Is a Light Year?
A light year sounds like a duration and is really a distance: the 9.5 trillion kilometres light covers in a year. Every glance up looks back in time.
Let’s go →A rusty planet
Why Is Mars Red?
Mars is red for the same reason an old nail is: its iron-rich dust has rusted. A whole planet the colour of something left out in the rain.
Let’s go →The strangest calendar
A Day on Mercury Lasts Longer Than Its Year
It laps the Sun in 88 days but takes 176 to get from one sunrise to the next, and radar has found ice in craters the sunlight never reaches.
Let’s go →Not a star at all
What Is a Shooting Star?
A grain of dust hits our air at tens of kilometres a second and burns out 80 km up. The glow is not friction — air squeezed that hard gets white hot.
Let’s go →You live inside it
What Is the Milky Way?
We sit 26,000 light years out in a disc 100,000 light years across and barely 1,000 thick, so looking along the plate turns countless stars into a stripe.
Let’s go →A true space story
Where the Moon Came From
The Moon is the piece of Earth that got knocked loose and never fell back, thrown into the sky by one enormous crash into the young planet.
Let’s go →It was never a night object
Why Can You See the Moon in Daytime?
It rises about fifty minutes later each day on its own timetable. A full Moon is a night object, but a half Moon stands high in broad afternoon.
Let’s go →Further than you think
How Far Away Is the Moon?
The Moon sits about 384,000 km away — a gap wide enough to line up every other planet in the solar system, side by side, with room to spare.
Let’s go →Measured by laser since 1969
The Moon Is Leaving, Four Centimetres a Year
The Moon is slowly being flung outward by the tides it raises, and the bill is paid by Earth's rotation — which is why days were shorter for the dinosaurs.
Let’s go →Too far away to fall behind
Why Does the Moon Follow the Car?
A hedge sweeps past in a second and a far hill barely stirs. The Sun, the planets and every star hold their place on a journey for the same reason.
Let’s go →Leave most of the ship behind
How Did the Astronauts Get Back Off the Moon?
The bottom half kept the legs and the descent engine and simply stayed put. The cabin fired off it and only had to reach the ride waiting in orbit.
Let’s go →Same ball, different view
Why the Moon Changes Shape
Exactly half the Moon is lit at every moment. The phase is only the angle you happen to be looking at that half from, and one lap takes 29.5 days.
Let’s go →A star nursery
What Is a Nebula?
A nebula is a vast cloud of gas and dust: both the raw material that stars condense out of, and the wreckage they scatter when they die.
Let’s go →Far out and furious
The Windiest Place in the Solar System
Neptune has the fastest winds in the solar system, around 2,000 km/h, despite receiving the least sunlight — and nobody fully explains why.
Let’s go →A city that weighs a sun
What Is Left After the Explosion?
A supernova leaves its crushed core behind: a ball the width of a city, holding more material than the Sun, spinning hundreds of times a second.
Let’s go →Nothing to carry the sound
Why Is Space Silent?
Sound has to be handed from one particle to the next, and space has essentially no particles to do the handing, so nothing out there is heard.
Let’s go →Falling without ever landing
What Is an Orbit?
An orbit is a permanent fall: move sideways fast enough and the ground below curves away exactly as quickly as you drop towards it.
Let’s go →Gravity pulls from all sides
Why Is Every Planet a Ball?
Anything big enough pulls itself into a ball, because gravity tugs equally from every side and rock is not strong enough to resist it.
Let’s go →A definition, not a demotion
Why Is Pluto Not a Planet Any More?
Finding Eris, heavier than Pluto, forced a choice: name a tenth planet or redraw the line. Pluto now leads a category instead of trailing one.
Let’s go →Not friction
Why Do Spacecraft Get So Hot Coming Back?
A capsule coming home at eight kilometres a second is not rubbed hot by the air. It squashes the air in front of it, and squashed air glows.
Let’s go →Pushing on nothing
How Do Rockets Launch?
A rocket flies by throwing hot gas downward very fast. The recoil from that throw is what lifts it, with nothing outside to push against.
Let’s go →Fast enough to miss
How Do Satellites Stay Up?
A satellite is not floating, it is falling — sideways, so fast that Earth keeps curving away underneath it before it can ever arrive.
Let’s go →Nine times wider than Earth
Saturn Would Float in a Big Enough Bath
Saturn is enormously heavy and enormously light at the same time, and the difference between those two words is the whole of this page.
Let’s go →Billions of orbiting snowballs
What Are Saturn's Rings Made Of?
The rings are billions of separate ice chunks, each on its own orbit. They only look solid from far away, and the sheet is astonishingly thin.
Let’s go →A tilted planet
Why Do Seasons Change?
Earth leans, and the lean makes the seasons: it changes how steeply the sunlight lands and how long it stays. Distance from the Sun is irrelevant.
Let’s go →Falling forever
Why Planets Orbit the Sun
A planet is not held on a string. It is falling towards the Sun and moving sideways fast enough to keep missing, over and over, forever.
Let’s go →The Sun is leaking
What Is the Solar Wind?
The Sun leaks a steady stream of particles that blows out past every planet. Earth's magnetic field is the reason almost none of it reaches us.
Let’s go →A shell of debris
What Happens to Old Satellites?
Dead satellites and fragments keep orbiting for years, and at eight kilometres a second even a stray fleck of paint is dangerous.
Let’s go →Home at 28,000 km/h
Living on the Space Station
Sixteen sunrises a day, food that floats, and no such thing as a floor. Every ordinary habit has to be rebuilt for a place where nothing ever falls.
Let’s go →Both, and neither
Is Space Hot or Freezing?
Space is neither hot nor freezing in any useful sense. Temperature needs particles, and there are almost none — objects there heat and cool by light alone.
Let’s go →Working outside
What Is a Spacewalk Like?
Space offers nothing — no air, no warmth, no up. A spacewalk means wearing a personal spacecraft, tethered to the one you just climbed out of.
Let’s go →From a cold cloud
How Does a Star Get Started?
A star begins as a cold cloud of gas falling in on itself, and switches on when the squeezed centre finally reaches about ten million degrees.
Let’s go →Colour is temperature
Why Are Some Stars Red and Others Blue?
A star's colour is a thermometer you can read from a hundred light years away: red is the cool end, blue-white the hot end. It says nothing about size.
Let’s go →The Sun is not the big one
How Big Do Stars Get?
Stars run from smaller than Earth to wide enough to swallow Jupiter's orbit. Our Sun, enormous next to our planet, sits unremarkably in the middle.
Let’s go →The air is doing it
Why Do Stars Twinkle but Planets Do Not?
The twinkling happens in our restless air, not in the star. A star is a single point of light for the air to bend; a planet is wide enough to average out.
Let’s go →A sun, seen from far away
What Is a Star?
Nothing in a star burns — there is no oxygen out there. Its own weight crushes the middle to millions of degrees, and the light leaks out of that.
Let’s go →Five billion years from now
What Will Happen to the Sun?
The Sun will not explode. It will swell into a red giant, swallow the inner planets, shed its outer layers and end as an Earth-sized ember.
Let’s go →Not burning at all
What Is the Sun Burning?
The Sun is not on fire. Its own weight crushes hydrogen into helium, and the scrap of mass lost in that swap comes back out as light and heat.
Let’s go →Bigger than your brain wants
How Big Is the Sun?
109 Earths would span the Sun's face and 1.3 million would fill it. It holds 99.8% of everything in the solar system, and among stars it is ordinary.
Let’s go →A very slow journey with a fast ending
The Last Eight Minutes Were the Easy Part
Energy from the Sun's core takes an enormous time to bounce its way out before the eight-minute run to Earth — and that delay is very hard to pin down.
Let’s go →The heaviest stars only
How Does a Star Explode?
A giant star spends its life holding itself up. When its core can no longer push back it falls in within a second, and the rebound tears it apart.
Let’s go →A bigger eye
How Do Telescopes Work?
A telescope is a bucket for light, and the wider the bucket the more it catches — far more starlight than a pupil a few millimetres across ever could.
Let’s go →Tipped right over
Why Does Uranus Spin on Its Side?
Every other planet spins like a top. Uranus is tipped 98 degrees and rolls along its orbit like a barrel, giving each pole a forty-year summer.
Let’s go →A blanket that will not lift
Why Is Venus Hotter Than Mercury?
Venus sits further from the Sun than Mercury yet runs far hotter, because its thick carbon dioxide blanket traps heat airless Mercury loses.
Let’s go →Earth & sky
Weather, light, and the air around us — 6 stories.
All earth & sky →It thins rather than ends
Where Does the Air Stop?
Half of all the air sits below five and a half kilometres, lower than several mountain ranges, and the space station still feels a whisper of it.
Let’s go →Light getting bounced
Why Is the Sky Blue?
Air molecules knock short blue waves sideways about ten times more readily than red ones, so blue arrives at your eyes from every patch of sky at once.
Let’s go →You are already moving very fast
What If the Earth Stopped Spinning?
If Earth stopped turning, everything loose would keep going east at the speed of a rifle bullet — and the sea would slide off the middle of the planet.
Let’s go →Gravity does not care about the ground
What If the Earth Were a Cube?
A cube-shaped Earth would have eight corners sticking out above the air, and all the water and air pooled into six round seas.
Let’s go →Light taking the long way
Why Are Sunsets Orange?
Near the horizon a sunbeam crosses roughly forty times as much air as at noon, and almost all of its blue is scattered away before it ever reaches you.
Let’s go →The Moon pulling
Why Does the Sea Go In and Out?
The Moon pulls the ocean into two bulges on opposite sides of the planet, and Earth turns through both, which is why high tide comes round twice a day.
Let’s go →Physics
Invisible forces you can play with — 3 stories.
All physics →The pull you never notice
What Is Gravity?
Every object with mass pulls on every other one. Earth simply has enough mass for its pull to dominate everything you have ever felt.
Let’s go →Sun overhead
Why Are Shadows Short at Noon?
Shadow length is a reading of the Sun's height, nothing more. The Sun is highest at midday, so that is when your shadow is at its stubbiest.
Let’s go →Empty space cannot push
What Does Nothing Actually Do?
Air strikes every square centimetre of you with about a kilogram of force, from all sides at once — which is why a can crumples and you do not.
Let’s go →Math
Number ideas with toys — 2 stories.
All math →Two clocks that do not match
Why Does a Year Have 365 Days?
A year is one orbit and a day is one spin, and neither divides neatly into the other. The leftover quarter of a day is what leap years exist to mop up.
Let’s go →Noon cannot be everywhere at once
Why Is It a Different Day Somewhere Else?
Clocks are set by the Sun and the Sun is only overhead in one place at a time, so the planet's turn is cut into stripes an hour wide.
Let’s go →How things work
Everyday machines, taken apart — 2 stories.
All how things work →And that is the boring half
Your Phone Beats the Computer That Flew to the Moon
The computer that landed Apollo 11 had less memory than one photo, and it was enough — because it did one job perfectly rather than everything adequately.
Let’s go →Four clocks and some arithmetic
How Does a Phone Know Where It Is?
Nothing tracks your phone. It times signals from several satellites, turns each delay into a distance, and solves for the only point that fits.
Let’s go →What things are made of
Atoms, metal, glass, plastic, and every kind of stuff — 1 story.
All what things are made of →Animals
Creatures on land, in the sea, and in the air — 1 story.
All animals →Everyday wonders
Kitchen, bubbles, echoes, and odd little magic — 1 story.
All everyday wonders →