× About Kosmophany Kosmophany — from the Greek kosmophania , "making the cosmos visible" — maps 13.8 billion years onto Carl Sagan's Cosmic Calendar . If all of time were compressed into a single year, the Big Bang would be January 1 and the present moment would be midnight on December 31.
Zoom from the full year overview down to individual cosmic seconds. At the deepest zoom level, each cosmic second spans ~438 real years — all of recorded human history fits in the last ~11 seconds of December 31.
16 Scientific Eras The default color mode divides cosmic history into 16 scientifically-defined eras:
1. Primordial Jan 1 · Big Bang through recombination (Planck, quark, hadron, lepton, nucleosynthesis epochs) 2. Dark Ages Jan 1–4 · No stars, neutral hydrogen fills the cosmos 3. Cosmic Dawn Jan 4–11 · First stars (Population III) ignite 4. Reionization Jan 11–27 · UV from first stars ionizes intergalactic gas 5. Galaxy Assembly Jan 27 – Mar 21 · Galaxies form through mergers and accretion 6. Cosmic Noon Mar 21 – May 15 · Star formation rate peaks at redshift z~2 7. Stellar Era May 15 – Sep 2 · Heavy elements build up; Milky Way disk forms 8. Hadean Sep 2–20 · Earth forms, Moon-forming impact, Late Heavy Bombardment 9. Archean Sep 20 – Nov 2 · First life, prokaryotes, banded iron formations 10. Proterozoic Nov 2 – Dec 17 · Great Oxidation, eukaryotes, Snowball Earth 11. Paleozoic Dec 17–24 · Cambrian explosion, fish, land plants, reptiles 12. Mesozoic Dec 24–30 · Dinosaurs, birds, flowering plants, mammals emerge 13. Cenozoic Dec 30 – Dec 31 ~22:20 · Mammals diversify, primates evolve 14. Quaternary Dec 31 22:20 – 23:59:33 · Ice ages, genus Homo, stone tools 15. Holocene Dec 31 23:59:33 – 23:59:59 · Agriculture, civilizations, written history 16. Modern Dec 31 23:59:59 – midnight · Industrial revolution to present 8 Thresholds of Complexity The Big History Project identifies eight key thresholds that mark the emergence of greater complexity in the universe:
1. The Big Bang The Universe begins 2. Stars Light Up First stars; later galaxies form 3. New Chemical Elements Forged in stars and supernovae 4. Earth & the Solar System Planets and "Goldilocks" conditions 5. Life Life emerges on Earth 6. Collective Learning Language and culture accelerate change 7. Agriculture Farming, villages, cities, states 8. The Modern Revolution Fossil fuels, industrialization, rapid global change Scaling Law of Evolution Biological and cultural revolutions follow an accelerating pattern: each major transition arrives faster than the last, following a geometric progression that converges toward the present. This "scaling law" was independently discovered by researchers studying the timing of evolutionary breakthroughs — from the emergence of life through the rise of civilizations.
The 21 phases progress from the pre-biotic cosmos through ever-shorter intervals of innovation: the first biosphere lasted 2.5 billion years, the Paleozoic 335 million, the Neolithic just 5,000. The pattern suggests that complexity itself accelerates the pace of change.
Pre-Scaling 13.8–10 Ga · Primordial cosmos, before the pattern begins Galactic Chemistry 10–7 Ga · Heavy elements enable prebiological chemistry Prebiological 7–4 Ga · Rocky planets form, organic chemistry intensifies First Biosphere 4–1.5 Ga · Prokaryotes dominate for 2.5 billion years Post-Oxygen 1.5 Ga–570 Ma · Eukaryotes, multicellularity Paleozoic 570–235 Ma · Cambrian explosion through land conquest Mesozoic 235–66 Ma · Dinosaurs, mammals, flowering plants Cenozoic 66–24 Ma · Mammalian radiation Hominoids 24–4.5 Ma · Great apes, bipedalism First Homo 4.5–2 Ma · Stone tools, genus Homo Lower Paleolithic 2 Ma–700 ka · Oldowan tools, out of Africa Fire 700–400 ka · Control of fire doubles the energy budget Acheulean 400–150 ka · Standardized hand axes Mousterian 150–40 ka · Levallois technique, symbolic thought Upper Paleolithic 40–11 ka · Art, music, cultural explosion Neolithic 11–6 ka · Agriculture, first villages Urban 6–2.75 ka · Cities, writing, empires Axial Age 2.75–1.5 ka · Philosophy, world religions Post-Classical 1.5 ka–500 ya · Printing, exploration Industrial 500–170 ya · Steam, fossil fuels Information 170 ya–present · Computers, internet, AI Colors: Hawaii scientific colour map (Crameri 2018), perceptually uniform and CVD-friendly.
Color Modes Eras — 16 scientific eras (default). Thresholds — 8 Big History Thresholds of Complexity. Geological — Official ICS 2023/09 colors for geological periods. Regimes — Four regimes: Cosmos, Earth, Life, Humanity. Scaling — 21 phases of the evolutionary scaling law (Snooks-Panov).
Regimes ● Cosmos — The universe: Big Bang, stars, galaxies, Solar System ● Earth — Our planet: tectonics, climate, extinctions ● Life — From the first cell to human evolution ● Humanity — Civilizations, science, and the modern world Zoom Levels The calendar supports 6 levels of semantic zoom:
Year — 12 month blocks, ~1.15 billion years per month Month — Individual day cells, ~37.8 million years per day Day — 24 hour slots, ~1.575 million years per hour Hour — 60 minute slots, ~26,300 years per minute Minute — 60 second slots, ~438 years per second Second — Sub-second detail Data Sources Geological period boundaries and colors: ICS Chronostratigraphic Chart v2023/09 and CGMW colour codes.
Events are compiled from scientific literature, Wikipedia timelines (CC-BY-SA), and curated by GLOBAÏA.
Controls Scroll or pinch to zoom. Drag to pan. Click on an event marker to see details. Keyboard: + /- zoom, 0 reset, Esc close panels.
Credits The Cosmic Calendar concept was created by Carl Sagan in The Dragons of Eden (1977) and Cosmos (1980).
Built by GLOBAÏA .