118 bricks · one universe

Everything is built from the same bricks.

A star, a tree and you are made of the same chemical elements. Each little square below is one Lego stud, worth 1% of the weight. The pieces are the same. Only the recipe changes.

The brick box

All 118 bricks of the universe

This is every kind of atom we know. Tap any element to see where in the cosmos it was made, whether it's inside you, and what everyday things use it. Change the view to recolor the whole table.

Recipes

What is it made of?

Pick anything: a tree, the ocean, the Sun, your phone. Its recipe snaps together as 100 studs, and the same bricks light up on the periodic table. Look how often the same few elements show up.

Side by side

Compare any two things

Same bricks, different pattern

Change the pattern, change the thing

These pairs share the same bricks, sometimes the exact same count. What makes them different is how the atoms are arranged, or a single brick added. The bricks stay. The pattern changes.

Play

Brick builder

Tap bricks to add them to the tray, and tap a brick in the tray to take it out. When your count matches a real substance, it appears. Try two H and one O first.

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Recipe cards

Tap a card to load its bricks, or find them yourself.

Where the bricks came from

Star forge

The universe did not start with 118 bricks. It started with almost only hydrogen and helium. Every other element was forged later, in stars and stellar explosions. Follow the story in order.

A giant star near the end of its life is layered like an onion. Each shell fuses heavier bricks, down to an iron core.

Why fusion stops at iron: building up to iron releases energy. Building past it costs energy, so the star's furnace goes out.

Experiment

The alchemy lab: can you make gold?

For centuries alchemists melted metals together hoping to make gold. Run their experiment yourself. Then look inside the atom to see why it never worked, and what it really takes.

Step 1 · The furnace

Melt two metals together

Pick two metals and heat them.

Try lead and mercury, the alchemists' favourites.

Step 2 · Inside the atom

What makes gold gold?

Protons decide what it isCount them and you know the element. 79 protons is always gold. 82 is always lead.

Neutrons decide which versionChange them and you get an isotope: still the same element, just heavier or lighter.

Electrons decide how it bondsThey hold atoms together in molecules and alloys. Chemistry happens out here.

Protons

Neutrons

Electrons

Melting and mixing only moves electrons. The protons sit locked in a nucleus 100,000 times smaller than the atom. No flame, acid or furnace can reach them.

Step 3 · The light-speed clash

Change the nucleus itself

To turn lead into gold you must knock 3 protons out of the nucleus. That takes atoms flying at almost the speed of light. Fire two lead beams past each other and watch.

Chemistry (bonds)

Nuclear (protons)

Bar lengths on a log scale. Pulling a proton out of a nucleus takes millions of electron-volts per atom, roughly a million times more energy than breaking a chemical bond (a few electron-volts).

This really happened. In 2025, scientists on the ALICE experiment at CERN's Large Hadron Collider reported that lead nuclei passing each other at 99.999993% of the speed of light had turned into gold. Between 2015 and 2018 they made about 86 billion gold nuclei. That's only about 29 trillionths of a gram, and each one broke apart within a tiny fraction of a second. Gold can be made, but only by smashing nuclei, never by mixing.

From atoms to feelings

Your feelings are built from four bricks

The molecules your brain uses to carry feelings are made from carbon, hydrogen, nitrogen and oxygen, sometimes with a little sulfur. These are the same bricks found in the Sun and in a blade of grass. Tap a molecule to see its bricks.

Same bricks, moved around

From your dinner to your mood

Your body takes amino acids from food and turns them into messenger molecules. Each step just adds or removes a few bricks.

Live

A thought, in sodium and potassium

A nerve signal is a wave of charged atoms crossing a cell wall. Sodium rushes in, then potassium flows out and resets the cell. It travels up to about 100 meters per second, and your brain fires billions of these every second.

An open question

So where does consciousness come from?

A molecule of dopamine is not a feeling on its own. Feelings and awareness seem to come from the pattern: about 86 billion neurons wired by your life, passing these molecules and ions back and forth. The atoms in your brain are ordinary. They're the same as those in a rock or a star. What's special is the arrangement. How that arrangement becomes the experience of being you is one of the biggest unsolved questions in science.

Can we build life from bricks?

Building life with chemistry

If living things are made only of ordinary elements, then in principle life could be assembled from chemicals. Scientists have been testing that idea for 200 years. Here's how far they've come.

You are star bricks, arranged to wonder about stars.

Your body holds about 7 billion billion billion atoms. The hydrogen is from the Big Bang, and the oxygen, carbon and calcium came from stars that lived and died before the Sun was born. The same bricks build stars, oceans, trees and minds. The only difference is the pattern.