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  • Euh? When did the Millennium Start?
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Euh? When did the Millennium Start?

The CNL Editor , IT/User Support


Abstract

If you feel like being polemic with your colleagues over a coffee, we offer you something to debate about and warm up your temperaments.


This article is based on information found by browsing the Web, and extracted mainly from the 2 following pages:

  1. "Start of the next millennium... an astronomer's answer" , by Tomaz Zwitter, Astronomical Observatory of University of Ljubljana, Slovenia.
  2. "The New Millennium Started On 1/1/2001" , a compilation made by Walter Schittek, Philipps-Universität Marburg, Deutschland.

The debate is more or less over, but, for one year and three months, you have probably been involved in some animated discussion around this issue. For most of the journalists in all European countries there was no doubt: January 1st 2001 had signalled the start of the XXIth century and the 3rd millennium. But can we trust journalists? Obviously this choice helped them to produce again, one year after the big events for 2000, attractive titles on their newspapers, always good for marketing and business. We tried, in User Support, to search on the Web in order to get some scientific explanation on the subject and here are some sensible conclusions (historical and scientific) we could extract.

The statement which is made to prove that we started a new millennium on 1st January 2001 (and not 1st January 2000) is that the date calculation has started with 1/01/0001 and not with 1/01/0000, forgetting at the beginning to define a "Year 0". If you start counting at the year 0, the third millennium started with the year 2000. We count hours, minutes, miles and ages of people beginning at 0, why not calendar years?

Gregorian Calendar versus astronomical chronology

1582, the Gregorian Calendar was created which defines the chronology still in use today. Counting of the years "after the birth of Christ" (A.D.) was already established at that time: it was invented by a scholar called Dionysius Exiguus in the 6th century (525 AD). Before that, there was (besides others) the varronic calculation which started counting from the foundation of Rome. A.D. 1 is equivalent to the varronic year 754. The varronic year 1 became then 753 B.C., i.e. there is no year 0, the year 1 B.C. being directly followed by A.D. 1 (Sequence ... 3 B.C., 2 B.C., 1 B.C., A.D. 1, A.D. 2, A.D. 3 ...). At first sight, that could be interpreted as an error, simply because the Roman numerals had no number zero! But many people today think it is not a mistake, but that this "ordinal counting" (enumerating the elements and naming them with their order, i.e. the 1st, the 2nd, etc... or element 1, element 2, ...), versus "cardinal counting" (0,1, 2, etc...) was correctly used for calendaring: cardinal counting gives the value 0 if there is not yet one complete element, whereas the first incomplete element already gets the ordinal number 1. Year 0 in cardinal counting becomes 1st year in ordinal counting!

However, the lack of a year 0 was disturbing for the astronomers in their need for a continuously extendible time axis. Astronomers frequently need to calculate how many days passed between the given two dates, for example when calculating times of eclipses of binary stars. Calendar date is not practical for this purpose, because of all the complications with different month lengths and leap years. Consequently they invented the astronomical chronology. And there you have a year 0, which is equal to 1 B.C., there are even negative years, where the year -1 is equal to 2 B.C. and so on.

Everybody agrees however that a century is a period of 100 years, and a millennium a period of 1000 years. Then, this quick and short review of only 2 calendaring conventions (one historical and one scientific) proves that the answer to the question depends on what you consider to be the origin: if you are a 000-fan (i.e., as on your car, with the switching of the counter to "000"), it is 2000, but if you want to wait 2000 years after January 1st of year 1AD, it is of course January 1st 2001.

Note that there are many other calendars in use than the Gregorian Calendar, e.g. Jewish, Moslem, Buddhist, that started the numbering of years at a different time than the Julian/Gregorian calendar, and therefore do not celebrate the 3rd Millennium at the same time!

Historical Statements

Jesus Christ's birth
Today's knowledge says that Jesus Christ was born at least 2 years before year 1 which means that those who wanted to celebrate the 2000th birthday of Jesus Christ should really have done that during the nineties. This never lead however to a redefinition of chronology in any country of the world.

2nd millennium
Already before the year 1700, people quarrelled about when the new century would begin. Before each turn of the century, there were some intense confrontations between differing majorities. 100 years ago, nearly all official fixings were made for 1/1/1901, except in Germany, which was caused by a preference of Kaiser Wilhelm II. On December 14, 1899, the German Bundesrat decided that the 1/1/1900 had to be taken as the beginning of the 20th century, which means that the end of the 2nd millennium must have been on December 31, 1999. Ultimately, that was a redefinition of the term "century": e.g. the (German) "dtv Brockhaus Lexikon" writes about the term "century": ... the 20th century began on January 1, 1901 and will finish on December 31, 2000. (translated)

3rd millennium
For this 3rd millennium, the U.S. government gave a statement referring to the U.S. Naval Observatory, with the result 1/1/2001. Similar statement were made by the Royal Greenwich Observatory, UK, and most other countries. The German Bundestag did not have to decide this question, because the Physikalisch-Technische Bundesanstalt has already given clear statements, with the same result!

What about the 4th millennium ? Unfortunately or fortunately we will not be there to launch the polemic again!



For matters related to this article please contact the author.
Cnl.Editor@cern.ch


CERN-CNL-2001-001
Vol. XXXVI, issue no 1


Last Updated on Thu Apr 05 15:28:12 CEST 2001.
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