1820

1820 (MDCCXX) wis a loup year stairtin on Seturday o the Gregorian calendar^[1] an a loup year stairtin on Thursday o the Julian calendar,^[2] the 1820th year o the common auld days (CE) an anno domini (AD) designations, the 820th year o the 2nd millennium, th 20th year o the 19th hunner years, an the 1st year o the 1820s decade. As o the stairt o 1820, the Gregorian calendar wis 12 day ahead o the Julian calendar, that remained in localised uiss til 1923.^[3]

References

↑ Dershowitz, Nachum; Reingold, Edward M. (2008). Calendrical calculations (3. ed., 1. publ ed.). Cambridge: Cambridge Univ. Press. ISBN 978-0-521-70238-6.
↑ "Julian calendar | History & Difference from Gregorian Calendar | Britannica". www.britannica.com (in Inglis). Retrieved 26 Mey 2025.
↑ Urban, Sean E.; Seidelmann, P. Kenneth, eds. (2012). Explanatory supplement to the Astronomical almanac (3rd ed.). Mill Valley, Calif: University Science Books. ISBN 978-1-891389-85-6.

[1] Dershowitz, Nachum; Reingold, Edward M. (2008). Calendrical calculations (3. ed., 1. publ ed.). Cambridge: Cambridge Univ. Press. ISBN 978-0-521-70238-6.

[2] "Julian calendar | History & Difference from Gregorian Calendar | Britannica". www.britannica.com (in Inglis). Retrieved 26 Mey 2025.

[3] Urban, Sean E.; Seidelmann, P. Kenneth, eds. (2012). Explanatory supplement to the Astronomical almanac (3rd ed.). Mill Valley, Calif: University Science Books. ISBN 978-1-891389-85-6.

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