{"id":623625,"date":"2026-01-18T22:05:42","date_gmt":"2026-01-18T21:05:42","guid":{"rendered":"https:\/\/cronologia-universale.it\/august-27-1942\/"},"modified":"2026-01-18T22:05:42","modified_gmt":"2026-01-18T21:05:42","slug":"january-28-1939","status":"publish","type":"post","link":"https:\/\/cronologia-universale.it\/en\/january-28-1939\/","title":{"rendered":"January 28, 1939"},"content":{"rendered":"<p>United States. Enrico Fermi speculates on the size of the crater produced by the fission of one kilogram of uranium. He estimates that one pound of fissile material produces an explosion equivalent to 15,000 tons of TNT. A small number of scientists now realize the terrifying weapon of destruction this represents.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>United States. Enrico Fermi speculates on the size of the crater produced by the fission&#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":[43],"tags":[],"class_list":["post-623625","post","type-post","status-publish","format-standard","hentry","category-vg-en"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.0 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>January 28, 1939 - 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\/january-28-1939\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"January 28, 1939 - Cronologia Universale\" \/>\n<meta property=\"og:description\" content=\"United States. 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