Cosmic Calendar

The Cosmic Calendar is a way of imagining the extent of the history of the universe by summarizing its age over 13.8 billion years to a year alone. In this picture, the Big Bang occurred at the beginning of January 1st, and the present is summarized at the end of December 31st of midnight. On this scale, every second means 438 years, every hour means 1.58 million years, and every day means 37.8 million years.

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This concept was popularized by Carl Sagan in his book, The Dragons of Eden, and his television series, Cosmos. In the sequel of 2014, Cosmos: A Spacetime Odyssey, host of Neil deGrasse Tyson uses the same Cosmic Calendar concept but its natural age should be revised to 13.8 billion years, improving the 15 billion years Sagan presented in 1980. Sagan also makes a comparison with surface area. He explained that if the Cosmic Calendar is stretched the size of a football field, then the whole of human history is just as wide as the palm of the hand

Then if the entire history of the universe is compressed into a year or in a calendar, then using this timescale, a month will be approximately equal to 1.1 billion years. The picture below explains more closely the event of an important event that occurs when we imagine the universe in one year:

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Let's look at the calendar in a little more detail:

Cosmic Year

Date	Billion Years	Event
Jan 1st	13.8	Big Bang
March 15st	11.0	The Milky Way Galaxy is formed
August 31st	4.57	the sun is formed (Planet and satellite shortly thereafter)
Sept 16st	4.0	The oldest known rock on earth
Sept 21st	3.8	first life (prokaryotes)
Oct 12st	3	photosynthesis
Oct 29st	2.4	atmospheric oxygenation
Nov 9st	2	complex cells (eukaryotes)
Des 5st	1	The first multicell life
Des 14st	0.67	simple animals
Des 14st	0.55	ancestral insects (arthropods)
Des 18st	0.5	fish and amphibious proto
Des 20st	0.45	Land plants
Des 21st	0.4	insects and seeds
Des 22st	0.36	amphibians
Des 23 st	0.3	Reptile
Des 26st	0.2	mammals
Des 27st	0.15	Bird
Des 28st	0.13	Flower
Des 30 at 06:24	0.065	The lime-paleogen extinction event, a non-bird dinosaur extinct

So, if the age of our universe compresses into 1 year, then we (modern humans or homo sapiens) only exist about 8-7 minutes ago and the history we know is only our history a few seconds ago from the moment .

Best Regard @t4r1