{"id":202764,"date":"2025-06-21T14:45:10","date_gmt":"2025-06-21T14:45:10","guid":{"rendered":"https:\/\/www.europesays.com\/uk\/202764\/"},"modified":"2025-06-21T14:45:10","modified_gmt":"2025-06-21T14:45:10","slug":"get-ready-for-the-shortest-day-since-records-began-as-earth-spins-faster","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/uk\/202764\/","title":{"rendered":"Get Ready For The Shortest Day Since Records Began As Earth Spins Faster"},"content":{"rendered":"<p>Topline<\/p>\n<p>Earth could be about to record its fastest-ever rotation. Since 2020, Earth has been rotating faster than at any point since records began in 1973, with each successive year producing the shortest day. Last year, the shortest day was recorded on July 5, and Earth is expected to get close to this again on or close to July 9, July 22 and August 5, according to <a href=\"https:\/\/www.timeanddate.com\/news\/astronomy\/earth-fast-rotation-2025\" rel=\"nofollow noopener noreferrer\" target=\"_blank\" class=\"color-link\" title=\"https:\/\/www.timeanddate.com\/news\/astronomy\/earth-fast-rotation-2025\" data-ga-track=\"ExternalLink:https:\/\/www.timeanddate.com\/news\/astronomy\/earth-fast-rotation-2025\" aria-label=\"Timeanddate.com\">Timeanddate.com<\/a>.<\/p>\n<p class=\"color-body light-text\" role=\"button\">&#8220;Rapidly spinning globe. Symbolic of time passing, travel and other metaphors of space and time.&#8221;<\/p>\n<p>getty <\/p>\n<p>Key Facts<\/p>\n<p>Earth takes a nominal 24 hours to rotate once on its axis, which is equal to 86,400 seconds.<\/p>\n<p>Until 2020, Earth&#8217;s rotation had been gradually slowing down, and the shortest ever day recorded was just 1.05 milliseconds under 86,400 seconds. However, on July 19, 2020, Earth rotated 1.47 milliseconds less than 86,400 seconds. Last year, on July 5, it was even shorter at 1.66 milliseconds.<\/p>\n<p>Since 2020, Earth has seen 28 of its fastest days and predictions from timeanddate.com, International Earth Rotation and Reference Systems Service and U.S. Naval Observatory indicate that Earth will again rotate faster on July 9, July 22 or August 5.<\/p>\n<p>The uncertainty comes from the exact position of the moon, which acts as a drag factor, particularly when it&#8217;s close to the equator. In the long-term, the moon is gradually slowing down the Earth\u2019s rotation, its gravitational pull causing tides and making Earth\u2019s orbital path around the sun slightly elliptical.<\/p>\n<p>Precise measurements of the length of a day come from atomic clocks and monitoring by the IERS.<\/p>\n<p>Why Earth\u2019s Rotation Is Accelerating<\/p>\n<p>Scientists do not know why Earth&#8217;s rotation has been speeding up since 2020. various factors are likely at play, including the motion of Earth&#8217;s core and mantle, a shifting of mass due to the melting of ice sheets and glaciers, and variations in ocean currents and air movement. All of these could influence the day length by milliseconds. It could also be down to the <a href=\"https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2022\/08\/03\/do-we-need-the-first-ever-drop-second-a-new-wobble-by-earth-caused-the-shortest-day-since-records-began-say-scientists\" target=\"_self\" class=\"color-link\" title=\"https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2022\/08\/03\/do-we-need-the-first-ever-drop-second-a-new-wobble-by-earth-caused-the-shortest-day-since-records-began-say-scientists\" data-ga-track=\"InternalLink:https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2022\/08\/03\/do-we-need-the-first-ever-drop-second-a-new-wobble-by-earth-caused-the-shortest-day-since-records-began-say-scientists\" aria-label=\"\u201cChandler wobble\u201d\" rel=\"noopener\">\u201cChandler wobble\u201d<\/a> \u2014 the movement of Earth\u2019s geographical poles across its surface.<\/p>\n<p>Time For Negative Leap Seconds?<\/p>\n<p>Historically, international timekeepers have added leap seconds to keep atomic time aligned with Earth\u2019s spin. However, since Earth is now rotating faster, not slower, so leap seconds are redundant. Instead, negative leap seconds\u2014 i.e., removing a second) \u2014 are being considered. IERS <a href=\"https:\/\/maia.usno.navy.mil\/products\/leap-second\" rel=\"nofollow noopener noreferrer\" target=\"_blank\" class=\"color-link\" title=\"https:\/\/maia.usno.navy.mil\/products\/leap-second\" data-ga-track=\"ExternalLink:https:\/\/maia.usno.navy.mil\/products\/leap-second\" aria-label=\"confirmed\">confirmed<\/a> earlier this month that no leap second would be added in 2025. The last leap second was positive and used at the end of December 2016. Scientists are unsure what to do because the current speeding-up may be a blip in a longer trend of Earth\u2019s rotation slowing.<\/p>\n<p>Why It Matters<\/p>\n<p>It may seem trivial, but the fact that Earth is spinning faster in 2025, shaving milliseconds off the day, is critical for maintaining time accuracy worldwide. Maintaining alignment between Earth time and atomic time is crucial for GPS and satellite navigation, financial systems reliant on precise timestamps and synchronizing networks across the world.<\/p>\n<p>Further Reading<a class=\"embed-base color-body color-body-border link-embed embed-8\" href=\"https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2025\/06\/16\/see-planets-pop-as-solstice-strikes-the-night-sky-this-week\/\" target=\"_blank\" aria-label=\"See Planets Pop As Solstice Strikes: The Night Sky This Week\" rel=\"noopener noreferrer\" data-ga-track=\"forbesEmbedly:https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2025\/06\/16\/see-planets-pop-as-solstice-strikes-the-night-sky-this-week\/\">ForbesSee Planets Pop As Solstice Strikes: The Night Sky This WeekBy Jamie Carter<\/a><br \/>\n<a class=\"embed-base color-body color-body-border link-embed embed-6\" href=\"https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2025\/06\/18\/city-killer-asteroid-could-now-hit-the-moon---what-to-know\/\" target=\"_blank\" aria-label=\"\u2018City Killer\u2019 Asteroid Could Now Hit The Moon \u2014 What To Know\" rel=\"noopener noreferrer\" data-ga-track=\"forbesEmbedly:https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2025\/06\/18\/city-killer-asteroid-could-now-hit-the-moon---what-to-know\/\">Forbes\u2018City Killer\u2019 Asteroid Could Now Hit The Moon \u2014 What To KnowBy Jamie Carter<\/a><br \/>\n<a class=\"embed-base color-body color-body-border link-embed embed-5\" href=\"https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2025\/06\/17\/theres-suddenly-a-40-chance-planet-nine-exists---what-to-know\/\" target=\"_blank\" aria-label=\"There\u2019s Suddenly A 40% Chance \u2018Planet Nine\u2019 Exists \u2014 What To Know\" rel=\"noopener noreferrer\" data-ga-track=\"forbesEmbedly:https:\/\/www.forbes.com\/sites\/jamiecartereurope\/2025\/06\/17\/theres-suddenly-a-40-chance-planet-nine-exists---what-to-know\/\">ForbesThere\u2019s Suddenly A 40% Chance \u2018Planet Nine\u2019 Exists \u2014 What To KnowBy Jamie Carter<\/a> <\/p>\n","protected":false},"excerpt":{"rendered":"Topline Earth could be about to record its fastest-ever rotation. Since 2020, Earth has been rotating faster than&hellip;\n","protected":false},"author":2,"featured_media":202765,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[81798,81800,81799,32617,81794,81796,81795,70,81793,81797,16,15],"class_list":{"0":"post-202764","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-day-length-variation","9":"tag-earth-spinning-faster","10":"tag-earths-core","11":"tag-earths-rotation","12":"tag-fast-earth-spin","13":"tag-leap-second","14":"tag-record-day-length","15":"tag-science","16":"tag-shortest-day-2025","17":"tag-timekeeping","18":"tag-uk","19":"tag-united-kingdom"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@uk\/114721896857301736","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/202764","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/comments?post=202764"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/202764\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media\/202765"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media?parent=202764"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/categories?post=202764"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/tags?post=202764"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}