SOUL/ALLOY Science · Cosmic Origin

Where Did We Come From?

A Journey from Present to 13.8 Billion Years Ago

The elements that make up your body. When, where, and how were they created? Follow the grand story uncovered by science, with evidence at every step.

Present

We Are Here

Right now, you are reading these words. Your body is made of about 60 trillion cells. And those cells are made of atoms.

Elements in Your Body

OOxygen65%
CCarbon18.5%
HHydrogen9.5%
NNitrogen3.2%
CaCalcium1.5%
PPhosphorus1%
Others (K, S, Na, Cl, Mg...)1.3%
When and where were these elements created? Let's travel back in time to explore their origins.
8

~66 Million Years Ago

Act 1: Rise of Mammals

We humans are mammals. And mammals could flourish because of the mass extinction 66 million years ago. Dinosaurs went extinct, and the age of mammals began.

Scientific Evidence

Iridium layer at K-Pg boundary — Abnormally high iridium concentrations found in geological strata worldwide at this boundary

Scientific Evidence

Chicxulub Crater — 180km diameter impact crater in the Gulf of Mexico

Scientific Evidence

Disappearance of dinosaur fossils and increase in mammal fossils — Geological records show dramatic ecosystem change

7

250M - 440M Years Ago

Act 2: Big Five — History of Mass Extinctions

The history of life has experienced five mass extinctions. Life has continued to evolve, overcoming each crisis.

End-Ordovician440 million years ago

85%

Late Devonian370 million years ago

75%

End-Permian250 million years ago

96%

End-Triassic200 million years ago

80%

End-Cretaceous66 million years ago

76%

Scientific Evidence

Fossil record discontinuities, chemical composition changes in strata, oxygen isotope ratio variations all support these extinction events.

6

~2.4 Billion Years Ago

Act 3: Oxygen Revolution — Gift of Cyanobacteria

The Great Oxidation Event (GOE). Photosynthesis by cyanobacteria caused a dramatic rise in atmospheric oxygen. It fundamentally changed Earth's environment.

Cause

Cyanobacteria released massive amounts of O₂ through photosynthesis. The previously reducing atmosphere became oxidizing.

Effect

Mass extinction of anaerobic organisms. However, this paved the way for complex life (eukaryotes) to evolve.

Scientific Evidence

Banded Iron Formations (BIF) — Layers where iron ions in the ocean reacted with oxygen and precipitated

Scientific Evidence

Red sandstone — Evidence of atmospheric oxygen oxidizing iron on land

5

~3.8-4.0 Billion Years Ago

Act 4: Origin of Life

Where and how did the first life emerge? There are several compelling hypotheses.

Hydrothermal Vent Theory

Life emerged near deep-sea hydrothermal vents, utilizing chemical energy.

RNA World Hypothesis

RNA served as both catalyst and genetic information carrier, giving rise to the first self-replicating system.

Panspermia Theory

The seeds of life may have arrived from space on meteorites.

Scientific Evidence

Oldest microfossils in Greenland (3.8 billion years old)

Scientific Evidence

Carbon isotope ratios — ¹²C/¹³C ratio characteristic of life activities

Scientific Evidence

Stromatolites — Layered structures of cyanobacteria from 3.5 billion years ago

4

~4.6 Billion Years Ago

Act 5: Birth of Earth

About 50 million years after the solar system formed, Earth was born. Gas and dust from the protoplanetary disk gathered, and planetesimals repeatedly collided and merged to form Earth.

Planetary Accretion

Planetesimals from the protoplanetary disk repeatedly collided and merged, growing to Earth-sized over about 100 million years.

Moon Formation

Giant Impact hypothesis — A Mars-sized body collided with proto-Earth, and the Moon formed from the debris.

Scientific Evidence

Meteorite dating (4.567 billion years) — The oldest solid material in the solar system

Scientific Evidence

Moon rocks (Apollo missions) — Isotope composition similar to Earth

Scientific Evidence

Zircon crystals — Earth's oldest minerals (4.4 billion years old)

So where did the elements that make up Earth come from?

3

~Hundreds of Millions of Years to Present

Act 6: Element Factory — Stars, Supernovae & Kilonovae

Most elements that make up Earth were created inside stars or in explosive events. 'We are made of stardust' is scientific fact.

Stellar Nucleosynthesis

H→He→C→O→...→Fe. Elements are synthesized sequentially at high temperature and pressure inside stars. Elements up to iron can be made by fusion.

Supernova Explosions

Some elements heavier than iron are created in supernova shockwaves. The s-process (slow neutron capture) also contributes.

Kilonovae (Neutron Star Mergers)

The heaviest elements like gold, platinum, and uranium are generated by r-process (rapid neutron capture) during neutron star mergers.

Scientific Evidence

Stellar spectrum analysis — Identifies element composition in stellar atmospheres

Scientific Evidence

GW170817 (2017 gravitational wave observation) — First observed neutron star merger, confirmed kilonova

Scientific Evidence

Solar abundance ratios — Element abundances match nucleosynthesis theory

2

~13.8 Billion Years Ago

Act 7: Big Bang — The First Three Minutes

The beginning of the universe. In the first three minutes, hydrogen, helium, and lithium were created. No other elements existed yet.

Hydrogen (H)

Helium (He)

Lithium (Li)

Scientific Evidence

Cosmic Microwave Background (CMB) — The 'afterglow' of the Big Bang, discovered in 1965

Scientific Evidence

Element abundances — The cosmic H/He ratio matches Big Bang nucleosynthesis theory

Scientific Evidence

Hubble-Lemaître Law — Observational evidence of cosmic expansion

1

Just After Big Bang

Act 8: Symmetry Breaking — Why Matter Survived

Right after the Big Bang, matter and antimatter should have been created in equal amounts. Why is the universe filled with only matter? The answer lies in 'symmetry breaking.'

Why Matter > Antimatter?

CP symmetry breaking caused slight differences in how matter and antimatter behave. One part in a billion asymmetry. That's the origin of all matter in the universe.

Scientific Evidence

Wu Experiment (1957, Co-60) — First proved parity symmetry breaking

Scientific Evidence

K meson CP violation (1964) — Discovered CP symmetry breaking

Scientific Evidence

B meson CP violation (2001, Belle/BaBar) — Contributed to 2008 Nobel Prize

Epilogue: The Beginning of Beginnings

All was equal. Matter and antimatter, time and space. That was the beginning of beginnings.

The world of Symmetria. Perfect symmetry. Then Breakia appeared and broke the symmetry. And after 13.8 billion years, here we are.

'Why is there something rather than nothing?'

This question lies at the boundary of science and philosophy. Even current physics cannot fully answer it. New physics, unknown particles, yet-undiscovered symmetry breaking... The quest continues.