Space
Space
Crashy night-sky stories
Leftover bricks
What Are Asteroids?
Asteroids are rocky leftovers from when the planets were being built.
Let’s go →Not what you think
Why Do Astronauts Float?
Astronauts float because they and their ship are falling around Earth together.
Let’s go →Sky on fire, quietly
What Are the Northern Lights?
Particles from the Sun crash into high air and make it glow like a neon sign.
Let’s go →Gravity turned all the way up
What Is a Black Hole?
A black hole is matter packed so tightly that light cannot escape its pull.
Let’s go →A dirty snowball
What Is a Comet?
Comets are icy leftovers that steam into a bright tail near the Sun.
Let’s go →Join the dots
What Are Constellations?
Constellations are shapes we drew on the sky — the stars are not really grouped.
Let’s go →A very old puzzle
Why Is the Night Sky Dark?
The night sky is dark because the universe is young and still expanding.
Let’s go →More time in the light
Why Are Days Longer in Summer?
Summer days are longer because your half of Earth leans into the sunlight.
Let’s go →A spinning Earth story
Why Day Turns Into Night
Night is simply your side of Earth turned away from the Sun.
Let’s go →Three things in a line
What Happens in an Eclipse?
An eclipse is one space rock's shadow landing on another.
Let’s go →Watching for a tiny dip
How Do We Find Planets Around Other Stars?
Most exoplanets are found by the tiny repeating dip in starlight as the planet passes in front.
Let’s go →An island of stars
What Is a Galaxy?
A galaxy is an enormous gravity-bound island of stars, separated from other galaxies by near-total emptiness.
Let’s go →Yes, lots
Is There Gravity in Space?
Gravity fills all of space; it just weakens with distance and never quite stops.
Let’s go →Three centuries of weather
Jupiter's Storm That Never Stops
Jupiter's Great Red Spot is a storm bigger than Earth that never blows out.
Let’s go →A distance, not a time
What Is a Light Year?
A light year is a distance — how far light travels in twelve months.
Let’s go →A rusty planet
Why Is Mars Red?
Mars looks red because its dust is literally rusted iron.
Let’s go →Not a star at all
What Is a Shooting Star?
Shooting stars are specks of dust burning up as they slam into our air.
Let’s go →You live inside it
What Is the Milky Way?
The Milky Way is our galaxy — and we see it as a band because we are inside it.
Let’s go →A true space story
Where the Moon Came From
A giant smash long ago threw up the rock that became our Moon.
Let’s go →It was never a night object
Why Can You See the Moon in Daytime?
The Moon is often up in daytime, and you can see it whenever it is bright enough to beat the blue sky.
Let’s go →Further than you think
How Far Away Is the Moon?
The Moon is 384,000 km away — far enough to fit every other planet in between.
Let’s go →Too far away to fall behind
Why Does the Moon Follow the Car?
The Moon appears to follow you because it is far too distant for your travel to shift its direction at all.
Let’s go →Leave most of the ship behind
How Did the Astronauts Get Back Off the Moon?
Getting off the Moon needed only a small rocket, because lunar gravity is weak and there is no air to fight.
Let’s go →Same ball, different view
Why the Moon Changes Shape
Half the Moon is always lit — phases are how much of that half faces you.
Let’s go →A star nursery
What Is a Nebula?
Nebulae are giant space clouds where stars are born and where they die.
Let’s go →Nothing to carry the sound
Why Is Space Silent?
Space is silent because sound is a wave in a material, and there is essentially no material out there.
Let’s go →Falling without ever landing
What Is an Orbit?
An orbit is a permanent fall: move sideways fast enough and the ground curves away as fast as you drop towards it.
Let’s go →Gravity pulls from all sides
Why Is Every Planet a Ball?
Planets are round because gravity pulls equally from all sides, and rock cannot hold any other shape at that size.
Let’s go →A definition, not a demotion
Why Is Pluto Not a Planet Any More?
Pluto lost its planet status because astronomers found many similar objects sharing its region of space.
Let’s go →Pushing on nothing
How Do Rockets Launch?
Rockets fly by hurling hot gas downward — the recoil lifts them.
Let’s go →Fast enough to miss
How Do Satellites Stay Up?
Satellites stay up by moving sideways so fast they keep missing Earth.
Let’s go →Billions of orbiting snowballs
What Are Saturn's Rings Made Of?
Saturn's rings are billions of separate ice chunks orbiting individually, not a solid hoop.
Let’s go →A tilted planet
Why Do Seasons Change?
Earth is tilted, so each half leans toward the Sun for part of the year.
Let’s go →Falling forever
Why Planets Orbit the Sun
Planets fall toward the Sun but move sideways fast enough to keep missing it.
Let’s go →The Sun is leaking
What Is the Solar Wind?
The solar wind is a steady stream of particles blowing out from the Sun.
Let’s go →A shell of debris
What Happens to Old Satellites?
Old satellites become debris that keeps orbiting, and at eight kilometres a second even tiny fragments are lethal.
Let’s go →Home at 28,000 km/h
Living on the Space Station
Life on the space station means everything you do has to be redesigned for free fall.
Let’s go →Both, and neither
Is Space Hot or Freezing?
Space is not really hot or cold, because temperature needs particles and space has almost none.
Let’s go →Working outside
What Is a Spacewalk Like?
A spacewalk means leaving the ship with your own tiny spaceship wrapped around you.
Let’s go →The air is doing it
Why Do Stars Twinkle but Planets Do Not?
Twinkling happens in our atmosphere, not in the star, and planets are too broad for it to show.
Let’s go →A night-sky flicker
Why Stars Twinkle
Moving air bends starlight on its way down, so the star seems to flicker.
Let’s go →Not burning at all
What Is the Sun Burning?
The Sun is not burning: crushing pressure fuses hydrogen into helium and releases enormous energy.
Let’s go →Bigger than your brain wants
How Big Is the Sun?
The Sun is so big that a million Earths would fit inside it.
Let’s go →A bigger eye
How Do Telescopes Work?
Telescopes gather far more light than your eye and focus it to a point.
Let’s go →A blanket that will not lift
Why Is Venus Hotter Than Mercury?
Venus beats Mercury for heat because its thick atmosphere traps warmth that Mercury simply radiates away.
Let’s go →