{"id":15854,"date":"2011-11-04T16:00:26","date_gmt":"2011-11-04T14:00:26","guid":{"rendered":"https:\/\/mamchenkov.net\/wordpress\/?p=15854"},"modified":"2011-11-04T16:00:26","modified_gmt":"2011-11-04T14:00:26","slug":"old-style-calendar","status":"publish","type":"post","link":"https:\/\/mamchenkov.net\/wordpress\/2011\/11\/04\/old-style-calendar\/","title":{"rendered":"Old style calendar"},"content":{"rendered":"<!-- google_ad_section_start -->\n<p>Growing up in USSR, since I was a kid, I remember I always had a confusion regarding the calendar.  While most dates were normal, a few were referred to as &#8220;old style&#8221; dates.  And even though I&#8217;ve asked around and it was explained to me a few times, I never truly understood what it was about.  I just new there was some calendar change in the past that created the shift.<\/p>\n<p>Today <a href=\"https:\/\/twitter.com\/#!\/mamchenkov\/status\/132417760243359744\">I tweeted<\/a> about Russia celebrating the <a href=\"http:\/\/en.wikipedia.org\/wiki\/Unity_Day_(Russia)\">Unity Day<\/a>.  Which I think is a silly replacement holiday for a huge celebration of the October Revolution.  For as long as I remember, it was celebrated on November 7th.  Then I realized that celebrating an October Revolution in November sounds strange.  Then I remembered that the revolution actually took place on October 25th, the &#8220;old style&#8221;. And November 7th is the same date but the &#8220;new style&#8221;.<\/p>\n<p>I am not a little boy back in the USSR anymore, I thought.  I am a man in the modern age, equipped with powerful tools, such as Google and Wikipedia.  No more should I suffer the confusion.  And thus I quickly found out the source and history of &#8220;old style&#8221; and &#8220;new style&#8221;.  Here is the relevant snipped from the Wikipedia page on the <a href=\"http:\/\/en.wikipedia.org\/wiki\/Julian_calendar#From_Julian_to_Gregorian\">migration from Julian to Gregorian calendar<\/a>.  I&#8217;ve highlighted the important and interesting bits.<\/p>\n<blockquote><p><strong>The Julian calendar was in general use in Europe and Northern Africa<\/strong> from the times of the Roman Empire until 1582, when Pope Gregory XIII promulgated the Gregorian calendar. <strong>Reform was required because too many leap days are added with respect to the astronomical seasons on the Julian scheme<\/strong>. On average, the astronomical solstices and the equinoxes advance by about 11 minutes per year against the Julian year. As a result, the calculated date of Easter gradually moved out of phase with the March equinox. While Hipparchus and presumably Sosigenes were aware of the discrepancy, although not of its correct value, it was evidently felt to be of little importance at the time of the Julian reform. However, it accumulated significantly over time: <strong>the Julian calendar gained a day about every 134 years. By 1582, it was ten days out of alignment from where it supposedly was in 325 during the Council of Nicaea.<\/strong><br \/>\nThe Gregorian calendar was soon adopted by most Catholic countries (e.g. Spain, Portugal, Poland, most of Italy).<br \/>\nProtestant countries followed later, and the countries of Eastern Europe adopted the &#8220;new calendar&#8221; even later. In the British Empire (including the American colonies), Wednesday 2 September 1752 was followed by Thursday 14 September 1752. For 12 years from 1700 Sweden used a modified Julian calendar, and adopted the Gregorian calendar in 1753, but <strong>Russia remained on the Julian calendar until 1918 (1 February became 14 February), after the Russian Revolution (which is thus called the &#8220;October Revolution&#8221; though it occurred in Gregorian November)<\/strong>, while Greece continued to use it until 1924.<\/p><\/blockquote>\n<!-- google_ad_section_end -->\n","protected":false},"excerpt":{"rendered":"<!-- google_ad_section_start -->\n<p>Growing up in USSR, since I was a kid, I remember I always had a confusion regarding the calendar. While most dates were normal, a few were referred to as &#8220;old style&#8221; dates. And even though I&#8217;ve asked around and it was explained to me a few times, I never truly understood what it was &hellip; <a href=\"https:\/\/mamchenkov.net\/wordpress\/2011\/11\/04\/old-style-calendar\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Old style calendar<\/span><\/a><\/p>\n<!-- google_ad_section_end -->\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false,"_links_to":"","_links_to_target":""},"categories":[1],"tags":[442,286,2909],"keyring_services":[],"class_list":["post-15854","post","type-post","status-publish","format-standard","hentry","category-general","tag-calendar","tag-history","tag-russia"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.8 - aioseo.com -->\n\t<meta name=\"description\" content=\"Growing up in USSR, since I was a kid, I remember I always had a confusion regarding the calendar. 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And even though I&#039;ve asked around and it was explained to me a few times, I never truly understood what it was\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"Leonid Mamchenkov\"\/>\n\t<meta name=\"google-site-verification\" content=\"VHvdD0_usx1_4DzKy_QCVcICVgX2EgA2ybELT-wl7kQ\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/mamchenkov.net\/wordpress\/2011\/11\/04\/old-style-calendar\/\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 4.9.8\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Leonid Mamchenkov - Life, universe, and everything else\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Old style calendar - Leonid Mamchenkov\" \/>\n\t\t<meta property=\"og:description\" content=\"Growing up in USSR, since I was a kid, I remember I always had a confusion regarding the calendar. 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Here are the release notes for\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":10269,"url":"https:\/\/mamchenkov.net\/wordpress\/2006\/07\/05\/back-to-gmail-ussr\/","url_meta":{"origin":15854,"position":1},"title":"Back to Gmail-USSR","author":"Leonid Mamchenkov","date":"July 5, 2006","format":false,"excerpt":"(please, forgive my untalanted Beatles reference) My email requirements have changed again. This time the changes are so significant that I am re-considering GMail. It looks promising. Why so? Well, the nature of my email discussions has changed so that GMail threads conversations handle my load best of all. Also\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":8912,"url":"https:\/\/mamchenkov.net\/wordpress\/2005\/04\/29\/minor-site-changes\/","url_meta":{"origin":15854,"position":2},"title":"Minor site changes","author":"Leonid Mamchenkov","date":"April 29, 2005","format":false,"excerpt":"I've modified the site theme a little bit. Calendar of posts is now only displayed on the main page. Additionally, when looking at some category, the category description and the link to category RSS feed will be displayed at the same place where calendar used to be. Categories RSS feeds\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":9394,"url":"https:\/\/mamchenkov.net\/wordpress\/2005\/08\/30\/tagging-calendars\/","url_meta":{"origin":15854,"position":3},"title":"Tagging calendars","author":"Leonid Mamchenkov","date":"August 30, 2005","format":false,"excerpt":"While playing around with Delicious I thought about how useful it would be to have a calendar which could operate with tags. This way, a jazz festival in Cyprus that is going to happen in Cyprus during 16-18 of September this year, for example, could have been tagged as \"jazz\",\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":17966,"url":"https:\/\/mamchenkov.net\/wordpress\/2013\/04\/09\/the-ussr-is-a-country-that-poses-a-serious-threat\/","url_meta":{"origin":15854,"position":4},"title":"The USSR is a country that poses a serious threat &#8230;","author":"Leonid Mamchenkov","date":"April 9, 2013","format":"quote","excerpt":"The USSR is a country that poses a serious threat to the Western world. I am not referring to the military threat is not actually there. Our countries are sufficiently well armed, including nuclear weapons. I'm talking about the economic threat. With the planned economy and the particular combination of\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":29077,"url":"https:\/\/mamchenkov.net\/wordpress\/2018\/12\/10\/spatie-period-complex-period-comparisons-in-php\/","url_meta":{"origin":15854,"position":5},"title":"spatie\/period &#8211; complex period comparisons in PHP","author":"Leonid Mamchenkov","date":"December 10, 2018","format":false,"excerpt":"spatie\/period is a PHP library that provides complex period comparisons.\u00a0 It implements a variety of methods for calculating gaps, boundaries, overlaps, and other operations on multiple dates.","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/posts\/15854","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/comments?post=15854"}],"version-history":[{"count":0,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/posts\/15854\/revisions"}],"wp:attachment":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/media?parent=15854"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/categories?post=15854"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/tags?post=15854"},{"taxonomy":"keyring_services","embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/keyring_services?post=15854"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}