01 / 09 - BODY
A temporary arrangement.
For a while, ancient matter is organized as you: breathing, remembering and asking where it came from.
- Inventory
- Roughly 7 x 10^27 atoms
- State
- Alive, exchanging matter
An elemental biography
You are stardust.
Follow the matter in your body backward through Earth, the Solar System, generations of stars and the universe's first minutes.
A temporary arrangement.
For a while, ancient matter is organized as you: a living system that continuously exchanges atoms with air, water and food.
Life carries a lineage.
Your DNA belongs to an unbroken biological lineage, but not an unchanging one. Replication, mutation and selection connect every living cell to earlier life.
An inventory of elements.
By mass, the human body is mostly oxygen, carbon, hydrogen and nitrogen, with calcium, phosphorus and many trace elements performing essential work.
Borrowed from Earth.
The atoms in you have circulated through oceans, atmosphere, rock, soil and other organisms. They are not possessions; they are participants in planetary cycles.
Gathered with the Sun.
Earth and the Sun formed about 4.6 billion years ago from one enriched molecular cloud and its protoplanetary disk.
Scattered by stellar deaths.
Stellar winds, planetary nebulae, supernovae and stellar mergers returned newly made elements to interstellar space, where later worlds could inherit them.
Forged across generations of stars.
Stars built carbon, oxygen and many heavier nuclei through fusion and related processes. Much of the iron in your blood traces its ancestry to explosive stellar events.
Hydrogen from the first minutes.
Most hydrogen nuclei formed during Big Bang nucleosynthesis. Neutral hydrogen atoms became possible about 380,000 years later when the universe cooled enough for electrons to bind.
The universe, briefly aware.
Your matter is ancient, but its present arrangement is new. For one human lifetime, part of the universe can examine the history that made it.