The Cosmic Timeline

Astrophysicists have deduced the age of the Universe

(dated from the Big Bang) to be

13.7 BILLION YEARS!















Imagine that the entire history of the universe is compressed into one year - with the Big Bang corresponding to the first second of the New Year's Day, and the present time to the last second of December 31st (midnight).

Using this scale of time, each month would equal a little over a billion years. Here's a closer look at when important events would occur when we imagine the universe in one year:





Let us look at the calendar in a bit more detail:



Cosmic Calendar (From The Dragons of Eden - Carl Sagan)

Pre-December Dates

Big Bang January 1 Origin of Milky Way Galaxy May 1 Origin of the solar system September 9 Formation of the Earth September 14 Origin of life on Earth ~ September 25 Formation of the oldest rocks known on Earth October 2 Date of oldest fossils (bacteria and blue-green algae) October 9 Invention of sex (by microorganisms) ~ November 1 Oldest fossil photosynthetic plants November 12 Eukaryotes (first cells with nuclei) flourish November 15

December

Sunday Monday Tuesday Wednesday Thursday Friday Saturday 1 Significant oxygen atmosphere begins to develop on Earth. 2 3 4 5 Extensive vulcanism and channel formation on Mars. 6 7 8 9 10 11 12 13 14 15 16 First Worms. 17 Precambrian ends. Paleozoic Era and Cambrian Period begin. Invertebrates flourish. 18 First oceanic plankton. Trilobites flourish. 19 Ordovician Period. First fish, first vertebrates. 20 Silurian Period. First vascular plants. Plants begin colonization of land. 21 Devonian Period begins. First insects. Animals begin colonization of land. 22 First amphibians. First winged insects. 23 Carboniferous Period. First trees. First reptiles. 24 Permian Period begins. First dinosaurs. 25 Paleozoic Era ends. Mesozoic Era Begins. 26 Triassic Period. First mammals. 27 Jurassic Period. First birds. 28 Cretaceous Period. First flowers. Dinosaurs become extinct. 29 Mesozoic Era ends. Cenozoic Era and Tertiary Period begin. First cetaceans. First primates. 30 First evolution of frontal lobes in the brains of primates. First hominids. Giant mammals flourish. 31 End of Pliocene Period. Quaternary (Pleistocene and Holocene) Period. First humans.

December 31

Origin of Proconsul and Ramapithecus, probable ancestors of apes and men ~ 1:30 p.m. First humans ~ 10:30 p.m. Widespread use of stone tools 11:00 p.m. Domestication of fire by Peking man 11:46 p.m. Beginning of most recent glacial period 11:56 p.m. Seafarers settle Australia 11:58 p.m. Extensive cave painting in Europe 11:59 p.m. Invention of agriculture 11:59:20 p.m. Neolithic civilization; first cities 11:59:35 p.m. First dynasties in Sumer, Ebla and Egypt; development of astronomy 11:59:50 p.m. Invention of the alphabet; Akkadian Empire 11:59:51 p.m. Hammurabic legal codes in Babylon; Middle Kingdom in Egypt 11:59:52 p.m. Bronze metallurgy; Mycenaean culture; Trojan War; Olmec culture; invention of the compass 11:59:53 p.m. Iron metallurgy; First Assyrian Empire; Kingdom of Israel; founding of Carthage by Phoenicia 11:59:54 p.m. Asokan India; Ch'in Dynasty China; Periclean Athens; birth of Buddha 11:59:55 p.m. Euclidean geometry; Archimedean physics; Ptolemaic astronomy; Roman Empire; birth of Christ 11:59:56 p.m. Zero and decimals invented in Indian arithmetic; Rome falls; Birth of Islam and the Islamic Civilization 11:59:57 p.m. Mayan civilization; Sung Dynasty China; Byzantine empire; Mongol invasion; Crusades 11:59:58 p.m. Renaissance in Europe; voyages of discovery from Europe and from Ming Dynasty China; emergence of the experimental method in science 11:59:59 p.m. Widespread development of science and technology; emergence of global culture; acquisition of the means of self-destruction of the human species; first steps in spacecraft planetary exploration and the search of extraterrestrial intelligence Now: The first second of New Year's Day