Illinois \u00dcniversitesi\u2019nde astronomi ve fizik profes\u00f6r\u00fc olarak \u00e7al\u0131\u015fan Brian Fields taraf\u0131ndan y\u00fcr\u00fct\u00fclen ve uluslararas\u0131 \u00f6l\u00e7ekte kat\u0131l\u0131mc\u0131lar\u0131 olan yeni bir ara\u015ft\u0131rma projesinde, 359 milyon y\u0131l \u00f6nce, yani Devoniyen ve Karbonifer d\u00f6nemleri aras\u0131ndaki s\u0131n\u0131rda ya\u015fanan t\u00fcr yok olu\u015flar\u0131nda astronomik olaylar\u0131n etkisine odaklan\u0131ld\u0131.<\/p>\n
Ulusal Bilimler Akademisi\u2019nin bir yay\u0131n\u0131nda (Proceedings of the National Academy of Sciences<\/em>) yer verilen ara\u015ft\u0131rmada biliminsanlar\u0131, Devoniyen-Karbonifer s\u0131n\u0131r\u0131na yo\u011funla\u015ft\u0131. \u00c7\u00fcnk\u00fc bu d\u00f6neme ait kaya\u00e7lar, ultraviyole \u0131\u015f\u0131k alt\u0131nda g\u00fcne\u015f yan\u0131\u011f\u0131 gibi g\u00f6r\u00fcnen ve say\u0131s\u0131 y\u00fcz binleri bulan bitki soylar\u0131na ait sporlar\u0131 i\u00e7eriyor. Sporlar\u0131 belirlemek i\u00e7in kullan\u0131lan bu ara\u015ft\u0131rma y\u00f6ntemi, ozon tabakas\u0131ndaki incelmenin \u00e7ok eski d\u00f6nemlere dayand\u0131\u011f\u0131n\u0131 da g\u00f6stermektedir. Fields konuya ili\u015fkin olarak, \u201cB\u00fcy\u00fck \u00f6l\u00e7ekli volkanik patlamalar ve k\u00fcresel \u0131s\u0131nma gibi d\u00fcnya kaynakl\u0131 felaketler de ozon tabakas\u0131n\u0131n tahrip olmas\u0131na neden olabilir. Ancak ara\u015ft\u0131rmada odaklan\u0131lan zaman aral\u0131\u011f\u0131 s\u00f6z konusu oldu\u011funda d\u00fcnya kaynakl\u0131 etkilere ili\u015fkin kan\u0131tlar yetersiz kalmaktad\u0131r. Bu nedenle, ozon tabakas\u0131n\u0131n uzun s\u00fcreli tahribat\u0131ndan, en az\u0131ndan ge\u00e7mi\u015f d\u00f6nemlerdeki tahribattan, D\u00fcnya\u2019dan yakla\u015f\u0131k 65 \u0131\u015f\u0131ky\u0131l\u0131 uzakl\u0131kta ger\u00e7ekle\u015fen bir veya daha fazla s\u00fcpernova patlamas\u0131n\u0131n sorumlu olabilece\u011fini d\u00fc\u015f\u00fcnmekteyiz\u201d a\u00e7\u0131klamalar\u0131nda bulundu.<\/p>\n Ara\u015ft\u0131rmac\u0131lar, s\u00fcpernova patlamalar\u0131n\u0131n yan\u0131 s\u0131ra g\u00f6kta\u015f\u0131 \u00e7apmas\u0131, g\u00fcne\u015f patlamalar\u0131 ve gama \u0131\u015f\u0131n\u0131 patlamalar\u0131 gibi astrofiziksel olaylar\u0131n ozon tabakas\u0131ndaki tahribata etki edip etmedi\u011fini de ara\u015ft\u0131rd\u0131. \u00c7al\u0131\u015fman\u0131n kat\u0131l\u0131mc\u0131lar\u0131ndan olan y\u00fcksek lisans \u00f6\u011frencisi Jesse Miller, \u201cBu t\u00fcr olaylar\u0131n Devoniyen d\u00f6neminin sonunda meydana gelen ozon tabakas\u0131 incelmesine neden olma olas\u0131l\u0131\u011f\u0131 d\u00fc\u015f\u00fck\u201d a\u00e7\u0131klamalar\u0131nda bulundu.<\/p>\n Biliminsanlar\u0131, bir s\u00fcpernova patlamas\u0131n\u0131n ozon tabakas\u0131 \u00fczerinde ikili bir y\u0131k\u0131c\u0131 etkiye sahip olabilece\u011fini ifade ediyor. Buna g\u00f6re patlama ilk olarak D\u00fcnya\u2019n\u0131n zararl\u0131 UV ve X \u0131\u015f\u0131nlar\u0131n\u0131n etkisinde kalmas\u0131na neden olur. Ard\u0131ndan, s\u00fcpernova kal\u0131nt\u0131lar\u0131nda meydana gelen patlamalar g\u00fcne\u015f sistemine etki eder ve gezegeni uzun s\u00fcreli kozmik \u0131\u015f\u0131nlar\u0131n etkisinde b\u0131rak\u0131r. S\u00fcpernova patlamas\u0131yla birlikte D\u00fcnya’ya ve ozon tabakas\u0131na verilen hasar ise 100.000 y\u0131l kadar devam edebilir.<\/p>\n Bununla birlikte fosil kal\u0131nt\u0131lar\u0131, bu d\u00f6nemde biyolojik \u00e7e\u015fitlilikte meydana gelen d\u00fc\u015f\u00fc\u015fe dikkat \u00e7ekiyor. Bu nedenle, Devoniyen-Karbonifer kitlesel yok olu\u015funa yol a\u00e7an astronomik olaylar\u0131n birden fazla olabilece\u011fi d\u00fc\u015f\u00fcn\u00fcl\u00fcyor. Ara\u015ft\u0131rmac\u0131lara g\u00f6re birden fazla s\u00fcpernova patlamas\u0131ndan s\u00f6z etmek bile m\u00fcmk\u00fcn. Miller konuya ili\u015fkin olarak “B\u00fcy\u00fck y\u0131ld\u0131zlar genellikle di\u011fer b\u00fcy\u00fck y\u0131ld\u0131zlarla birlikte k\u00fcmeler olu\u015fturur ve di\u011fer s\u00fcpernovalar\u0131n patlamas\u0131 ilk patlamadan hemen sonra meydana gelebilir” a\u00e7\u0131klamalar\u0131nda bulundu.<\/p>\n Ara\u015ft\u0131rmac\u0131lar, ozon tabakas\u0131ndaki incelmeye bir s\u00fcpernovan\u0131n neden olup olmad\u0131\u011f\u0131n\u0131 kan\u0131tlaman\u0131n anahtar\u0131n\u0131n, patlaman\u0131n ard\u0131ndan yery\u00fcz\u00fcnde biriken radyoaktif izotoplar\u0131n kaya\u00e7larda ve fosillerde bulunup bulunmad\u0131\u011f\u0131n\u0131 incelemek oldu\u011funu ifade ediyor. \u00c7al\u0131\u015fman\u0131n kat\u0131l\u0131mc\u0131lar\u0131ndan olan Zhenghai Liu, \u201cBu radyoaktif izotoplar\u0131n hi\u00e7biri D\u00fcnya’da do\u011fal olarak olu\u015fmuyor ve kaya\u00e7lardaki katmanlara ula\u015fabilmelerinin tek yolu ilgili d\u00f6nemlerde ger\u00e7ekle\u015fen kozmik patlamalar\u201d dedi.<\/p>\n Ara\u015ft\u0131rmac\u0131lar\u0131n bir sonraki ad\u0131m\u0131, Devoniyen-Karbonifer s\u0131n\u0131r\u0131ndaki kaya\u00e7larda radyoaktif izotoplar\u0131 ara\u015ft\u0131rmak olacak. Fields, “\u00c7al\u0131\u015fmam\u0131z\u0131n ana mesaj\u0131, D\u00fcnya’daki ya\u015fam\u0131n tek ba\u015f\u0131na var olmad\u0131\u011f\u0131d\u0131r. Biz daha b\u00fcy\u00fck bir kozmosun yurtta\u015flar\u0131y\u0131z ve kozmos genellikle fark ettirmeden, bazen de ac\u0131mas\u0131zca hayat\u0131m\u0131za m\u00fcdahale ediyor\u201d a\u00e7\u0131klamalar\u0131nda bulundu.<\/p>\n Kaynak:<\/strong> https:\/\/www.sciencedaily.com\/releases\/2020\/08\/200818142104.htm<\/p>\n","protected":false},"excerpt":{"rendered":" Illinois \u00dcniversitesi\u2019nde astronomi ve fizik profes\u00f6r\u00fc olarak \u00e7al\u0131\u015fan Brian Fields taraf\u0131ndan y\u00fcr\u00fct\u00fclen ve uluslararas\u0131 \u00f6l\u00e7ekte kat\u0131l\u0131mc\u0131lar\u0131 olan yeni bir ara\u015ft\u0131rma projesinde, 359 milyon y\u0131l \u00f6nce, yani Devoniyen ve Karbonifer d\u00f6nemleri aras\u0131ndaki s\u0131n\u0131rda ya\u015fanan t\u00fcr yok olu\u015flar\u0131nda astronomik olaylar\u0131n etkisine odaklan\u0131ld\u0131. Ulusal Bilimler Akademisi\u2019nin bir yay\u0131n\u0131nda (Proceedings of the National Academy of Sciences) yer verilen ara\u015ft\u0131rmada […]<\/p>\n","protected":false},"author":1390,"featured_media":46081,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19],"tags":[1188,5577,6959,2300],"class_list":["post-46079","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bilim-gundemi","tag-ozon-tabakasi","tag-patlama","tag-radyoaktif-izotop","tag-supernova"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts\/46079","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/users\/1390"}],"replies":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/comments?post=46079"}],"version-history":[{"count":0,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts\/46079\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/media\/46081"}],"wp:attachment":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/media?parent=46079"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/categories?post=46079"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/tags?post=46079"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}