{"id":615331,"date":"2026-01-18T17:20:43","date_gmt":"2026-01-18T16:20:43","guid":{"rendered":"https:\/\/cronologia-universale.it\/3850000000-bc\/"},"modified":"2026-01-18T17:20:43","modified_gmt":"2026-01-18T16:20:43","slug":"4200000000-bc","status":"publish","type":"post","link":"https:\/\/cronologia-universale.it\/en\/4200000000-bc\/","title":{"rendered":"4,200,000,000 BC"},"content":{"rendered":"<p>Latest evidence for a rotating magnetic (ferrous) core on the Moon. The experimental evidence comes from lunar samples made available by the Apollo missions, unshocked by impacts (which could also be the source of the magnetic field).<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Latest evidence for a rotating magnetic (ferrous) core on the Moon. The experimental evidence comes&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[39],"tags":[],"class_list":["post-615331","post","type-post","status-publish","format-standard","hentry","category-ge-en"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.0 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>4,200,000,000 BC - Cronologia Universale<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/cronologia-universale.it\/en\/4200000000-bc\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"4,200,000,000 BC - Cronologia Universale\" \/>\n<meta property=\"og:description\" content=\"Latest evidence for a rotating magnetic (ferrous) core on the Moon. 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