Day

A day is a unit of time defined as the length of time it takes for one complete rotation of the Earth on its axis. This period of time is approximately 24 hours. The concept of a day is used as a standard unit of time measurement in various contexts, such as in calendars, astronomy, and daily life. In most cultures, a day is typically divided into 24 equal parts called hours, and each hour is further divided into 60 minutes and each minute is divided into 60 seconds.

Earth's rotation imaged by Deep Space Climate Observatory, showing axis tilt

Our weeks have seven days because the ancient Babylonians had one day for each known celestial body: the Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn.

Ancient Egyptians had 12 months of exactly 30 days each, with five epagomenal days to bring the total to 365. Each month was divided into three 10-day periods known as decans or decades.

Monday is the only day of the week that is an anagram of a single word: ‘dynamo’.

The day of the week Tuesday is named after Tiw, the Norse god of single combat, victory and glory. Tiw is associated with Mars, the Roman god of war, which is why the day is Mardi in French, Martes in Spanish and Martedi in Italian.

The actress Tuesday Weld was born on a Friday.

According to a survey in 2002, Tuesday is the most productive day of the week in the workplace.

Wednesday is named after Woden, the most important God in the German pantheon, often identified with the Norse God Odin.  Woden and Odin are also associated with the Roman god Mercury, which is why the French call Wednesday Mercredi and the Spanish Miercoles.

The Japanese for Wednesday translates as ‘Water day’ as the planet Mercury was known as the ‘water star’.

In German, Wednesday (Mittwoch) is the only day of the week not ending in ‘tag’ (day).

The Wednesday before Easter is known as ‘Spy Wednesday’ referring to Judas’s betrayal of Jesus.

According to an extensive study of over 300 million events, April 11, 1954 was the most boring and uneventful day of the 20th century. The study, conducted by William Tunstall-Pedoe, a Cambridge computer scientist, found that no major events occurred on that day, and that no notable people were born or died. The only significant event that took place was a general election in Belgium.

Tunstall-Pedoe created a search engine called True Knowledge, which contains over 300 million individual facts. He used this search engine to scan through each day in the 20th century, looking for days with no major events. He found that April 11, 1954 was the day with the fewest major events.

In the Ancient Roman Empire, there were 24 hours in the day. The 24 hours were divided into equal parts 12-Light hours and 12-Dark hours. Therefore the length of an hour would change based on the seasons.

February 6, AD 60 is the earliest date for which the day of the week is known. A graffito in Pompeii identifies this day as a dies Solis (Sunday). In modern reckoning, this date would have been a Wednesday.

46 BC was 445 days long and is the longest year in human history. The year marked the change from the pre-Julian Roman calendar to the Julian calendar. 

Submarine crews do not use a typical 24 hour day, one day lasts 18 hours.

A day on the Moon is so slow that you could outrun the sun in a car and stay in perpetual sunlight.

Here is a list of songs with days of the week in the title

Source Daily Express