Holocene calendar facts for kids

The Holocene calendar, also called the Human Era (HE), is a way to number years that adds 10,000 years to our usual Anno Domini (AD) or Common Era (CE) calendar. This system places the first year close to the beginning of the Holocene period and the time when humans started farming and building cities (the Neolithic revolution). People who like the HE system say it makes it easier to date things in geology, archaeology, and history.

To find the Holocene year for 2025, you just add the number "1" in front of it. So, 2025 becomes 12025 HE. The idea for the Human Era was first suggested by a scientist named Cesare Emiliani in 1993 (which would be 11993 HE).

Here are some reasons why people wanted a new calendar:

• In the AD calendar, the year 1 is based on when Jesus was thought to be born. However, historians now believe he was born about four years earlier.
• Years before Jesus (called BC) count backwards as you go from the past to the future. This can make it hard to calculate how long ago something happened.
• The AD calendar doesn't have a year zero. It goes straight from 1 BC to year 1. This is important to remember when you're trying to figure out time spans.

Instead, the Human Era starts at 10001 BC. This is roughly when our current geological period, the Holocene, began. This was also the time when humans started building settlements, the first cities appeared, and agriculture began. Using the HE system means all important dates in human history can be listed on a simple timeline where smaller dates always come before larger dates.

Converting to the Human Era

It's easy to change years from the regular AD calendar to the Human Era. You just add 10,000 to the AD year.

For years before Jesus (BC years), you subtract the BC year from 10,001.

Here are a few examples:

• 10000 BC is 1 HE (This is considered the start of the Holocene).
• 1 BC is 10000 HE.
• AD 1 is 10001 HE.
• AD 2000 is 12000 HE.
• The current year, 2025, is 12025 HE.

See also

• Common Era
• Julian date (JD) – This is a way to count days and parts of days since January 1, 4713 BCE, at noon in Greenwich.

See also

In Spanish: Calendario holoceno para niños