| Planck Epoch |
The earliest known period of time in the history of the universe |
0 |
0.0000000000001 |
Temperature and density are extremely high. |
| Grand Unification Epoch |
The universe cools enough for gravitational, electromagnetic, weak, and strong forces to differentiate |
0.0000000000001 |
0.00000000000001 |
Forces combine into one. |
| Inflationary Epoch |
Period of rapid expansion of the universe |
0.00000000000001 |
0.000000000000001 |
Space stretches exponentially. |
| Electroweak Epoch |
The electromagnetic and weak nuclear forces unify |
0.000000000000001 |
0.00000000000000001 |
Symmetry breaking occurs. |
| Quark Epoch |
The universe cools enough for quarks to form |
0.0000000000001 |
0.00000000005 |
Formation of quarks occurs. |
| Hadron Epoch |
Quarks combine to form protons and neutrons |
0.00000000005 |
0.00000000001 |
Protons and neutrons are formed. |
| Nucleosynthesis Epoch |
Formation of the first atomic nuclei |
0.00000000001 |
0.0000002 |
Hydrogen and helium formed. |
| Photon Epoch |
The universe cools, allowing photons to dominate |
0.0000002 |
0.0000003 |
Photons free to travel, universe becomes transparent. |
| Recombination Epoch |
Electrons combine with nuclei to form neutral atoms |
0.0000003 |
0.0000004 |
Formation of neutral hydrogen. |
| Cosmic Microwave Background Radiation |
The resulting radiation from Recombination |
0.0000004 |
0.000001 |
CMB radiation fills the universe. |
| Dark Ages |
The period after CMB, before stars formed |
0.000001 |
0.0002 |
No stars or galaxies formed. |
| First Stars Epoch |
Formation of the first stars |
0.0002 |
0.0005 |
Stars ignite, light returns to the universe. |
| Reionization Epoch |
The universe becomes ionized again due to star light |
0.0005 |
0.05 |
Cosmic reionization occurs. |
| Stellar Epoch |
Formation of galaxies and clusters of galaxies |
0.05 |
5 |
Galaxies begin to form. |
| Solar System Formation |
Our solar system forms from a molecular cloud |
4.6 |
4.57 |
Formation of the Sun, planets, and moons. |
| Modern Astronomical Epoch |
The current epoch with diverse astronomical observations |
0.005 |
0 |
Development of Earth and life. |
| Amino Acid Epoch |
Formation of life's building blocks on Earth |
4.0 |
3.5 |
Prebiotic chemistry produces amino acids. |
| Ediacaran Period |
First complex multicellular life forms |
0.635 |
0.541 |
Multicellular organisms appear. |
| Cambrian Explosion |
Rapid diversification of life |
0.541 |
0.485 |
Animal phyla rapidly evolve. |
| Ordovician Period |
Diversification of marine life |
0.485 |
0.444 |
First land plants appear. |
| Devonian Period |
Age of fishes with first amphibians |
0.419 |
0.359 |
Fishes flourish and land colonization begins. |
| Carboniferous Period |
Development of extensive forests and coal deposits |
0.359 |
299 |
Giant insects and early reptiles appear. |
| Permian Period |
Pangea forms, ends with the largest mass extinction |
299 |
251 |
Ends with the Permian-Triassic extinction. |
| Triassic Period |
The rise of dinosaurs |
251 |
201 |
Dinosaurs and mammals develop. |
| Jurassic Period |
Dinosaurs dominate and complex ecosystems evolve |
201 |
145 |
Dinosaurs diversify. |
| Cretaceous Period |
Ends with the extinction of the dinosaurs |
145 |
66 |
Mass extinction event occurs. |
| Paleogene Period |
Mammals proliferate; birds evolve |
66 |
23 |
Mammals and birds diversify. |
| Neogene Period |
Rise of modern flora and fauna |
23 |
2.6 |
Formation of grasslands. |
| Quaternary Period |
Evolution of humans and last Ice Ages |
2.6 |
0 |
Continued evolution of species. |
| Hominid Evolution |
Emergence of human ancestors and technology |
6 |
0.2 |
Hominins evolve, tools develop. |
| Modern Human Epoch |
Homo sapiens dominate Earth, form civilization |
0.2 |
0 |
Humanity shapes the planet. |
| Anthropocene Epoch |
Impact of humans on the Earth system |
0.01 |
0 |
Human activity alters climates, ecosystems. |
| Future Epoch |
Projected future of the universe |
0 |
15 |
Possibility of heat death or Big Crunch. |
| Heat Death |
Theoretical end state of a universe cooled to near absolute zero |
15 |
End of time |
Entropy maximizes in universe. |
| Big Crunch |
Theoretical scenario where the universe collapses back to singularity |
15 |
End of time |
Universe contracts due to gravity. |
| Big Rip |
Theoretical scenario where the universe expansion accelerates to tear apart cosmological structures |
15 |
End of time |
Galaxies and stars are torn apart. |
| Frog Epoch |
Hypothetical future scenario with evolution of amphibians after human extinction |
1 |
End of time |
Amphibians dominate ecosystems. |
| Sun's Red Giant Phase |
The Sun expands into a red giant |
5 |
7.5 |
Inner planets are engulfed. |
| Black Hole Epoch |
Most remnants of stars are black holes |
100 |
End of time |
Very few stars remain. |
| Degenerate Era |
Stars burn out, black holes dominate |
1000 |
End of time |
Black holes form most mass in the universe. |
| Dark Era |
The universe becomes dark and cold |
1000 |
End of time |
No light sources exist. |
| Time of no stars |
All stars exhaust their fuel |
1000 |
End of time |
Only black holes and cold remnants exist. |
| Collapse of Protons |
Hypothetical decay of protons leads to end of matter |
10^30 |
End of time |
Matter ceases to exist. |
| Equilibrium Era |
Matter decays into radiation and foundational particles |
10^30 |
End of time |
Subatomic particles govern dynamics. |
| Radiation Era |
The universe is almost entirely radiation |
10^30 |
End of time |
Energy takes over as dominant force. |
| Quantum Fluctuation Epoch |
Fluctuations in quantum vacuum lead to new structures |
End of time |
New universe |
Potential for rebirth of structures. |
| Rebirth Epoch |
Hypothetical scenario with a new big bang |
End of time |
No time defined |
New universe begins. |
| Epoch of Cosmic Council |
Intelligent cosmic civilizations assume governance |
20 |
100 |
Civilizations manage galaxies and intergalactic relations. |
| Magma Ocean Epoch |
Early Earth with molten surface conditions |
4.4 |
4.2 |
Formation of initial crust begins. |
| Snowball Earth Epoch |
Earth's surface covered in ice |
720 |
635 |
Global glaciation events occurred. |
| Great Oxygenation Event |
Massive increase of oxygen in Earth's atmosphere |
2.5 |
2.0 |
Photosynthesis dramatically affects atmosphere. |
| Neoproterozoic Era |
Formation of complex life towards the end |
1000 |
541 |
Emergence of multicellular life. |
| Human Civilizational Epoch |
Recorded history with complex societies |
0.01 |
0 |
First civilizations emerge. |
| Space Exploration Epoch |
Humanity's exploration beyond Earth |
0.005 |
0 |
Manned moon and Mars landings. |
| Digital Information Age |
The creation of digital technologies |
0.01 |
0 |
Internet and digital communication become universal. |
| Climate Change Epoch |
Human-induced climate changes |
0.005 |
0 |
Significant impact on global ecosystems. |
| Post-Human Epoch |
Theoretical future after human civilization |
1 |
End of time |
Evolution of intelligent non-human successors. |
| Time of Synapses |
Potential for brain-machine integrations |
End of time |
End of time |
Neural interfaces revolutionize experiences. |
| Transcendental Epoch |
Humans evolve beyond physical limitations |
End of time |
End of time |
Consciousness expands into new realms. |
| Cyclic Universe |
Hypothesis of a universe that undergoes infinite cycles |
End of time |
End of time |
Each cycle has distinct epochs. |