Rocket science, explained
Answers to the questions children actually ask — written for the grown-up doing the explaining. Every article links to the book that shows it.
Do astronauts feel gravity? Yes — they just don’t feel their weight
Gravity at the space station is about 88% of what it is on your kitchen floor. Here is why that still produces floating, and what astronauts actually feel.
5 min readgravityorbitsmisconceptions
Why is space cold if the Sun is so hot?
Space is measured at 2.725 K, yet sunlight there is fierce enough to cook a spacecraft. Both are true, and the reason is that temperature needs something to be the temperature of.
5 min readspacetemperaturemisconceptions
How do astronauts breathe in space?
The oxygen is made on board by splitting water with electricity. The harder half of the problem — and the one nobody mentions — is taking the carbon dioxide back out.
5 min readISSlife supporthow it works
What would happen if you fell into a black hole?
You would be stretched apart by the difference in gravity between your head and your feet — and from the outside, you would appear to freeze at the edge and never quite arrive.
6 min readblack holesgravityspace
Why is the sky blue but space is black?
The sky is not blue because of anything blue. It is blue because air scatters short wavelengths in every direction — and where there is no air, there is nothing to scatter.
4 min readspacelightatmosphere
Why are rockets so big when the payload is so small?
A Falcon 9 weighs 549 tonnes and carries 22. The reason is one equation with a logarithm in it — and you can prove it to yourself in about a minute.
6 min readfuelstagingphysics
How fast does a rocket actually go?
Slower than you think at first, and far faster than you think at the end. The speeds at every stage of a launch, and why sideways is the number that matters.
5 min readspeedorbitslaunch
Why do astronauts float? (It is not because gravity is gone)
The most common misconception in spaceflight, explained simply — and the one-line sum that shows gravity is still almost as strong up there.
5 min readgravityorbitsmisconceptions
How does a rocket steer with no wings?
There is nothing to push against and no rudder that would work. Rockets turn by pointing their engines — and on the way home, by using four titanium waffles.
5 min readsteeringengineslanding
How do rockets work? An explanation that survives being questioned
Rockets do not push against the air or the ground. They push against the stuff they throw out of the back — and that single idea explains almost everything else.
6 min readbasicsenginesnewton
Where does space actually begin?
There is no wall and no line painted in the sky. Different countries even use different heights — which children find far more interesting than a single tidy answer.
4 min readatmospheredefinitions
How does a rocket land itself?
No wings, no parachute, and an engine too powerful to hover with. How a booster gets from 8,300 km/h to standing still on a ship, in about six minutes.
5 min readlandingreusefalcon 9
How to explain orbits to a child (without saying “zero gravity”)
A short guide for parents and teachers: the analogies that work, the ones that quietly cause problems later, and the order to introduce them in.
6 min readteachingorbitsparents