How is the date of Holy Week determined every year – science – life

This week is special in many parts of the world, not only because the last days of March and the first of April converge, but because it coincides with the celebration of Holy Week, an eight-day period that began last Sunday. It peaks next Sunday; The so-called Palm Sunday and Easter Sunday, respectively. It may interest you: Is the Standard Model for Elementary Particles cracked?

For Christians, the “Great Week”, as it was initially called, represents the most important week of the year, with a special liturgical activity, but unlike other celebrations that occur every year on the same specific dates, Easter has the specificity of commuting year after year In the calendar, it covers the different weeks between the months of March and April.

The only responsible is the moon. This is not a strange relationship between our natural satellite and human behavior, as many today try to argue.

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To illustrate this, we must go back to the year 325 AD when the first ecumenical council convened in Nicaea, at the invitation of Emperor Constantine I, “the Great”, and where it has been established that the moon will determine the date of Easter, so that the Sunday resurrection is celebrated on the Sunday after the completion of the first moon of the vernal equinox. The northern hemisphere, that is, after the vernal equinox of March, which corresponds to the beginning of spring in the northern hemisphere of the Earth.

In the same council, it was decided that the celebration would not coincide with the Jewish Passover, which commemorates the Exodus of the Children of Israel from Egypt under the leadership of Moses. At first it coincided with Christian and Jewish celebrations.

In this way, the lunar calendar determines the dates of Holy Week, so that every year does not coincide with the same days. The lunar cycles have a frequency with full moons occurring approximately every 29.5 days, while the Gregorian calendar is divided into months.

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Recently, the Second Vatican Council, convened by Pope John XXIII, opened the possibility of setting Easter on a specific date in the year, which is possible that in the future we will not have to look at the calendar at each beginning of the year to plan prayer days for some and rest for others, with The peculiarity is that the moon will have lost a little prominence.

Santiago Vargas
PhD in the Astronomical Observatory of Astrophysics at the National University of Colombia