{"product_id":"okloa-earths-own-reactor-physics-t-shirt","title":"Okloa – Earth's Own Reactor Physics T-Shirt","description":"\u003cp\u003eOkloa sleeps in the Gabon uranium rock and wakes every few hours. She was a working nuclear reactor two billion years ago.\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eAbout 2 billion years ago, uranium was richer in U-235 (about 3.7%), because U-235 decays faster than U-238. With groundwater slowing the neutrons, ore at Oklo sustained fission chain reactions, running about 30 minutes on and 2.5 hours off as the water boiled away and returned.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eU-235 half-life 0.704 Gyr;  U-238 half-life 4.468 Gyr\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU-235, U-238: uranium isotopes\u003c\/li\u003e\n\u003cli\u003eGyr: billion years (1 Gyr ≈ 3.16 × 10¹⁶ s)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eIn 1972 the CEA plant at Pierrelatte found Oklo uranium at 0.7171% U-235 instead of the usual 0.7202%, and as low as 0.296%; Meshik et al. (2004) worked out the on-off cycle.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e It never exploded like a bomb, and Oklo was not the only natural reactor.\u003c\/p\u003e\u003ch3\u003eOn the shirt\u003c\/h3\u003e\u003cp\u003eFront: Okloa, the pixel-art character, with the title. Back: the isotope numbers, the half-lives, the water-moderated cycle and the 1972 and 2004 sources. Printed on a unisex tee.\u003c\/p\u003e","brand":"Pixelated Physics","offers":[{"title":"S \/ White","offer_id":50936512643175,"sku":"16431439090107432498","price":29.99,"currency_code":"USD","in_stock":true},{"title":"S \/ Black","offer_id":50936512675943,"sku":"11511064029044231779","price":29.99,"currency_code":"USD","in_stock":true},{"title":"M \/ White","offer_id":50936512708711,"sku":"17523264113217242848","price":29.99,"currency_code":"USD","in_stock":true},{"title":"M \/ Black","offer_id":50936512741479,"sku":"18843661491744516800","price":29.99,"currency_code":"USD","in_stock":true},{"title":"L \/ White","offer_id":50936512774247,"sku":"25661820529941450028","price":29.99,"currency_code":"USD","in_stock":true},{"title":"L \/ Black","offer_id":50936512807015,"sku":"17940788541324731218","price":29.99,"currency_code":"USD","in_stock":true},{"title":"XL \/ White","offer_id":50936512839783,"sku":"23327612686517747862","price":29.99,"currency_code":"USD","in_stock":true},{"title":"XL \/ Black","offer_id":50936512872551,"sku":"73972986833151440566","price":29.99,"currency_code":"USD","in_stock":true},{"title":"2XL \/ White","offer_id":50936512905319,"sku":"21898073832860319572","price":29.99,"currency_code":"USD","in_stock":true},{"title":"2XL \/ Black","offer_id":50936512938087,"sku":"94971126563195639532","price":29.99,"currency_code":"USD","in_stock":true},{"title":"3XL \/ White","offer_id":50936512970855,"sku":"17884621677192353573","price":29.99,"currency_code":"USD","in_stock":true},{"title":"3XL \/ Black","offer_id":50936513003623,"sku":"12015483046609865357","price":29.99,"currency_code":"USD","in_stock":true},{"title":"4XL \/ White","offer_id":50936513036391,"sku":"31944577228642771151","price":29.99,"currency_code":"USD","in_stock":true},{"title":"4XL \/ Black","offer_id":50936513069159,"sku":"32076741288342697648","price":29.99,"currency_code":"USD","in_stock":true},{"title":"5XL \/ White","offer_id":50936513101927,"sku":"21925516278970653899","price":29.99,"currency_code":"USD","in_stock":true},{"title":"5XL \/ Black","offer_id":50936513134695,"sku":"24951280645410099305","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/oklo-reactor_front_01_white.png?v=1793595399","url":"https:\/\/pixelatedphysics.com\/hi\/products\/okloa-earths-own-reactor-physics-t-shirt","provider":"Pixelated Physics","version":"1.0","type":"link"}