January is the first month of the year in the Julian and Gregorian calendars and the first of seven months to have a length of 31 days.
It is a winter month in the northern half of the world and a summer month in the southern half.
January is, on average, the coldest month of the year within most of the Northern Hemisphere (where it is the second month of winter) and the warmest month of the year within most of the Southern Hemisphere (where it is the second month of summer).
January 1 is New Year’s Day in the Gregorian calendar that is used around the world. Many other cultures and calendars, however, celebrate their new year on other dates.
The Christian Orthodox New Year is celebrated on January 14, because the Orthodox Church still follows the Julian calendar. The Chinese calendar is lunisolar, following the Moon and the Sun. The Chinese New Year is celebrated some time between January 21 and February 21.
The old Roman calendar had only ten months. January and February did not exist—the year started in March. Around the year 700 BC, the Roman king Numa Pompilius is said to have added the two winter months.
January initially had 29 days and came after December, but the Roman year still started in March. In 154 BC, a rebellion forced the Roman senate to change the beginning of the civil year from March to January 1. With this reform, January officially became the first month in the year 153 BC.
In the year 46 BC, Julius Caesar introduced a new calendar system—the Julian calendar. He added ten days to the year and introduced the leap day. In the Julian calendar, January was expanded to 31 days.
Ancient Roman observances during this month include Cervula and Juvenalia, celebrated January 1, as well as one of three Agonalia, celebrated January 9, and Carmentalia, celebrated January 11. These dates do not correspond to the modern Gregorian calendar.
Various Christian feast dates were used for the New Year in Europe during the Middle Ages, including March 25 (Feast of the Annunciation) and December 25. However, medieval calendars were still displayed in the Roman fashion with twelve columns from January to December. Beginning in the 16th century, European countries began officially making January 1 the start of the New Year once again—sometimes called Circumcision Style because this was the date of the Feast of the Circumcision, being the seventh day after December 25.
January is named after Janus, the god of beginnings and transitions in Roman mythology. The gates of a building in Rome named after him (not a temple, as it is often called, but an open enclosure with gates at each end) were opened in time of war, and closed to mark the arrival of peace. As a god of transitions, he had functions pertaining to birth and to journeys and exchange, and in his association with Portunus, a similar harbor and gateway god, he was concerned with travelling, trading and shipping.
January is not only a month, but also part of the name of Brazil’s second biggest city: When the Portuguese expedition under Gaspar de Lemos landed at Guanabara Bay on the coast of South America in 1502, the calendar showed January 1. This is why the Portuguese named the place Rio de Janeiro (River of January).
In Finnish, the month of tammikuu means the heart of the winter and because the name literally means “oak moon”, it can be inferred that the oak tree is the heart of the grand forest with many valuable trees as
opposed to the typical Arctic forests, which are typically pine and spruce. The photograph of a large tree covered with ice against a blue sky is a familiar scene during Finland’s winter.
January’s birthstone is the garnet, which represents constancy. Garnets are most often seen in red, but are available in a wide variety of colors spanning the entire spectrum. A garnet has a hardness of 6.5 to 7.5 on the Mohs scale of mineral hardness. Depending on the variety, quality and size of a garnet, one can pay anywhere from $40 to $5,000 per carat.
Its birth flower is the cottage pink Dianthus caryophyllus or galanthus.
The Japanese floral emblem of January is the camellia (Camellia sinensis).
The zodiac signs for the month of January were Capricorn and Aquarius.
The name of the full moon occurring in January is the wolf moon.