Year (Meaning and Explanation)

We explain what a year is and what types exist according to how they are calculated. Also, we tell you why a light year is not a measurement of time.

What is a year?

one year It is a twelve month periodwhich can be measured from any day to the same date twelve months later. This period of time It is a conventional and historical way that humanity has created to measure timebased on their observations of the natural environment and, in many cases, their different religious speculations and cultural traditions.

In fact, The exact length of a year depends primarily on the type of calendar used.since each culture counted the passage of time in a different way. According to the Western calendar, each year includes twelve months, beginning in January and ending in December (both inclusive), throughout which the four climatic seasons occur.

This time measurement of 365 days on average serves as a template for thinking about other types of year, adapted to commercial, social or even astronomical realities. Other calendars count the years from “summers” or “harvests”, that is, using an eminently agricultural criterion.

The word “year” comes from Latin Annusa word that in Ancient Rome was used as a synonym for “year”, “season” or the long period of time it takes for the celestial constellations to recover their “initial” position (the so-called annus magnus or “big year”). Much of the Western way of thinking about time comes from the Roman calendar, to the point that the name of several of the months comes from the name of different emperors of this culture (Julius Caesar, Augustus and Octavian).

Types of year according to their calculation and duration

Within the concept of “year” it is important to differentiate between:

Astronomical, sidereal or sidereal year. It is determined in the most astronomically exact way, using the stars as a reference to measure when the Earth passes through the same point twice in its orbit around the Sun. It lasts 365 days, 6 hours, 9 minutes and 9.76 seconds.
Solar or tropical year. It is determined in a similar way to the astronomical year, taking as reference a specific star and the Earth's mean equinox. This was the method used by great ancient civilizations, such as the Mesopotamian, with surprising accuracy. It lasts 365 days, 5 hours, 48 minutes and 45.22 seconds.
Calendar year. It is determined from the count of elapsed days considered equivalent to a year, whether for civil or religious reasons, adjusting the day fractions so that the year coincides with the astronomical cycle. Its duration, being conventional, depends on the calendar used. In the Gregorian calendar, normal years last 365 days and leap years last 366.

leap years

A leap year, according to the current calendar model, is a year with an additional day, the result of the accumulation of the remaining fractions of time from each year (since a year lasts, astronomically, 365 days, 6 hours, 9 minutes and 9.76 seconds). So, These years have 366 days and occur every four years.

The term “leap” comes from Roman antiquity, specifically from the expression ““bis sextus dies ante calendas martii” (“repeated on the sixth day before the first day of March”), since at that time the additional day was interspersed between February 23 and 24, by instruction of Emperor Julius Caesar. Instead, The Gregorian calendar, in force since 1582, assigned this extra day to February 29.

Calendar year, business year and fiscal year

Although there is only one time, the way of counting it and the considerations given to it are not the same. This allows society to create “different” years, depending on the area of interest, from the same period of time, so a distinction must be made between:

calendar year. It corresponds to 365 days (366 for leap days) starting from any day and its repetition twelve months later. For example, there is a calendar year from January 7th and the following January 7th.
calendar year. It corresponds to the calendar year, that is, the year that begins on January 1 and ends on December 31, and is considered as a complete unit of time.
Business year. It corresponds to 360 days, due to the simplification and normalization of the year (establishing 30 days per month) for commercial and transactional purposes. It is useful for calculating interest in banks, rentals of goods and properties, and other matters important to commerce.
Fiscal or financial year. It corresponds to the calendar year, in the sense that it lasts 12 months, but it does not necessarily begin and end on the same days as this one. The fiscal year concerns only tax and payment obligations, which allows the annual financial activity to be sectored and organized.

School year

A school year, school year or academic year is a complete study cycle, that is, It is the annual period of days in which students go to their schools, institutes and universities. School years serve not only to determine when class periods begin and end (which may or may not coincide with the fiscal year, since vacations are not counted), but also to stratify study levels and separate them by years of instruction. : first year, second year, etc.

In some countries the school year begins in March and ends in December.as in Argentina; while In others it starts in September and ends in Julyor, like in Venezuela.

gap year

a sabbatical year It's a year of rest. It is an agricultural custom from Antiquity, specifically from Hebrew customs (shabbat means “the (day) of rest” and is also the origin of the day “Saturday”), which consisted of giving a year of “rest” to the land after every sixth consecutive year of harvest, so that the soil would replenish its nutrients. and will not be permanently exhausted.

Today, this term is used to refer to a year in which the individual leaves their activities, such as study or work, to dedicate themselves to other types of experiencessuch as traveling, practicing a language, volunteering, among others. Many times, young people take this year before starting their university studies or their first job.

Besides, It is used in the academic field, to name the periods of study and research available to teachers and university professors, who are expected to build new lines of research to then continue their teaching practice. In many cases these gap years are carried out at universities abroad, as part of exchange mechanisms.

Light-year

A light year (abbreviated al. or al) is a unit of length coined by astrophysics to express the distances of sidereal space, whose expression in kilometers would be too long and cumbersome. one light year It is equivalent to the amount of distance that light travels in a vacuum during the time span of one Julian year. (365.25 days of 24 hours each), that is, about 9.46 x 10¹² km or 9,460,730,472,580.8 km.

The term “light year” was first used formally in 1851, in a popular article by German astronomer Otto Ule (1820-1876). Given the rarity of a unit of length containing the temporal term “year”, it was considered for some time a term in German use, and is still considered today. some sectors of the specialized community prefer the use of parsec to the light year.

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