The longest year in Earth's history lasted 445 days. When did this happen?

Some years fly by in the blink of an eye, while others seem to stretch on much longer. It is known that a standard year lasts 365 days, but some, like leap years, can last a bit longer than usual — 366 days. However, scientists note that a leap year is not the longest in Earth's history, as reported by IFLScience.

A year is the time it takes for the Earth to complete one orbit around the Sun and return to the starting point. In an effort to break the year into segments, humans devised calendars that divide one planet's orbit around the Sun into months, weeks, and days.

Today, people have learned to better align the orbital year with our calendar years, for example, by adding "leap seconds" to achieve synchronization. However, earlier calendars were not nearly as effective.

Before Julius Caesar introduced the Julian calendar, the Roman year looked quite different: it consisted of four months (March, July, October, and May) each with 31 days, while others were shorter — only 29 days, except for the peculiar February, which had 28 days. As a result, the calendar quickly became out of sync with the Earth's movement around the Sun. By around 200 BC, the calendar had drifted so much that a nearly total eclipse, which is now observed on March 14, occurred on July 11.

To somewhat rectify the situation, people had to add an "intercalary month," known as Mercedonius, every few years. Unfortunately, this method was not the best for maintaining a calendar. Mercedonius could be used to align the calendar with the year, but it was open to political manipulation.

Later, Julius Caesar attempted to set things right by introducing the Julian calendar in 45 BC, adding one or two days to the end of all short months except February. As a result, the total number of days in a year became more familiar — 365. However, before the new calendar corrected the situation, there was still a lingering issue that needed resolution: the year still did not align with the seasons.

To address this problem, Caesar added several months to 46 BC: as a result, it lasted 445 days, which is 80 days longer than we are accustomed to. It is known that two additional months were added between November and December — thus, in 46 BC there were 15 months instead of 12.

Now researchers note that 46 BC became the longest year in recorded Earth's history. By the way, this year is sometimes referred to by scientists as the "year of confusion."