How do you know the date of Carnival?
13 fev 2025Clique aqui para ler este artigo em português
A very important piece of information for Brazilians is the date of Carnival each year.
— And how is this date calculated?
To understand this, you need to understand where Carnival came from.
Due to the variation in the inclination of the sun’s path throughout the year, as seen from Earth, the length of the day also varies. There are months when the days are short and the nights are long and others when the days are long and the nights are short.
There are two days in the year in which day and night have the same duration, which have been called “equinoxes”, a word that comes from Latin aequinoctium, meaning the day “equal to the night”. The equinoxes always occur close to March 21st and September 23rd.
The March equinox marks the beginning of Autumn in the Southern Hemisphere and the beginning of Spring in the Northern Hemisphere. Therefore, in Europe, North America and all countries in the Northern Hemisphere, it is called the “Spring equinox”, and it is a very important date, as it marks the end of Winter and the beginning of Spring.
Many ancient civilizations in the Northern Hemisphere celebrated this with a great feast, which occurred on the Spring equinox. To be able to celebrate better, at a time when there was no artificial lighting, a full moon night was good. Then, in many ancient civilizations, a celebration was held on the first full moon after the Spring equinox. This celebration is the origin of Easter.
In the centuries after Christ, the Catholic Church became the hegemonic political force in Europe, and ancient festival dates were adopted by it as its own festivities, including Easter, the date on which the resurrection of Christ began to be celebrated.
The Catholic Church considers Sunday a special day. For that reason, Easter was moved to Sunday. They decided that Easter should be celebrated on the first Sunday after the first full moon following the Spring equinox.
Let’s look at the example of 2025. This year, the equinox that starts Spring in the Northern Hemisphere (and starts Autumn in Brazil) is March 20th. Consulting a table of moon phases for 2025, we see that there is a full moon on the following dates:
February 12th – Full Moon
March 14th – Full Moon
March 20 – Equinox
April 12th – Full Moon
May 12th – Full Moon
The first full moon after the equinox therefore occurs on April 12th, which is already on the weekend. The following Sunday is April 20th. Therefore, Easter in 2022 falls on April 20th.
– Ok. And how does it relate to Carnival?
The week ending on Easter Sunday is called Holy Week in the Catholic calendar, and begins on the Sunday before Easter, called Palm Sunday.
Therefore, in 2025, Palm Sunday is April 13th.
The Catholic Church in the Middle Ages associated recollection and reflection with fasting from meat and alcohol. In order for the faithful to prepare spiritually for Holy Week, the Church established a 40-day fast period, ending on Palm Sunday. During these 40 days, a period called lent, the faithful were forbidden from eating meat, drinking alcohol and having sexual relations.
Well, the first calculation anyone makes in this situation is: what will be the last day I can eat meat, drink alcohol and have sex?
The math is simple. Starting on Palm Sunday, count back 40 days. You will see that the first day of fasting always falls on a Wednesday: Ash Wednesday in the Catholic calendar. So, in the days leading up to this date, let´s eat a lot of meat, drink a lot of alcohol, and have a lot of sex, because afterwards it will be prohibited (In Latin, carnem levare means “to abstain from meat.” Carne levare … carne vale … Carnival).
That’s it. Carnival was the last chance to eat meat, drink alcohol and have sex, before 40 days of preparation for the Holy Week.
In 2025, Palm Sunday is April 13th. Counting back 40 days, starting on the Palm Sunday, we find that Ash Wednesday is March 5th. Therefore, Carnival goes from March 1st to March 4th.
— Can you summarize all of this?
Yes. It’s like a board game:
- Find out the date of the March equinox in the year considered. It will always be on March 20th or 21st.
- Consult a table of moon phases to find out which is the first full moon after that date.
- From this full moon, go forward to next Sunday. You are on Easter.
- Go back seven days, until the Sunday before Easter. You are on Palm Sunday.
- Go back 40 days including Palm Sunday. You are on Ash Wednesday.
- Carnival is on the few days before it.
That’s it.
Marcos Chiquetto is an engineer, Physics teacher, translator, and writer. He is the director of LatinLanguages, a Brazilian translation agency specialized in providing multilingual companies with translation into Portuguese and Spanish.
