The Cosmic Calendar at Loiano


The Cosmic Calendar is located outside the building of the historical, 60 cm-diameter Zeiss Telescope, and uses an idea of Carl Sagan, a famous American astronomer and writer.

If we condense the current lifetime of the Universe into one year, it becomes evident that humankind is an extremely recent newcomer on the cosmic stage.

A sequence of pictures, properly spaced, compresses the history of the Universe into one year. Every cosmic month lasts 1250 billion years, each day represents 40 million years, and every second is equal to approximately 500 years of our history.

Thus, the Universe was born on January 1st (with the Big Bang occurring in the first tenth of a second of this day). 

The first stars and galaxies did not begin to form until the universe had cooled and expanded.

The Milky Way formed on the first day of May, the Solar System on September 9th, and the Earth around mid-September. The ‘infant’ Earth was a hot, molten and toxic place.

Life originated a bit later, around September 25th, probably in the air or in the oceans during the primordial era. The most basic plants, which used photosynthesis to supply energy, appear on November 12th. Green plants discharged large amounts of oxygen and nitrogen on December 1st.

On December 18th large quantities of trilobites are on the bottom of the oceans. Early vertebrates appear on December 19th, plants start to spread on December 20th; the first winged bugs begin to fly on December 22nd. In the same days the first amphibians, creatures able to live both on dry land and in water, also show up.

Dinosaurs appear on December 24th, on Christmas Eve, but their domain on our calendar is short.

Mammals appear two days later, and the first birds appear on December 27th. The appearance of first flowers and the extinction of the dinosaurs occur on December 28th.

Primates appear on December 29th.

Mankind and everything it has done are confined to the last day of the year.

Our ancestors made their appearance around 10:30 p.m. on December 31st (the first humans walk on Earth). At 11:32 p.m. they discovered fire, at 11:59 p.m. and 20 seconds they became farmers and domesticated animals, at 11:59 p.m. and 35 seconds they started building the first towns. At 11:59 p.m. and 59 seconds Columbus discovers America.

Our origin is so recent that the entire known human history occupies the very last seconds of the last minute of December 31st.

Visiting times

The Cosmic Calendar can be viewed every day and is located outside the historical Zeiss Telescope.

Additional information

You can consult the detailed description (in italian), or view the poster (in italian).

The Calendar was developed in 2009, on the occasion of the International Year of Astronomy.