{"id":30781,"date":"2018-11-12T01:01:29","date_gmt":"2018-11-11T22:01:29","guid":{"rendered":"https:\/\/bilimvegelecek.com.tr\/?p=30781"},"modified":"2018-11-11T11:31:14","modified_gmt":"2018-11-11T08:31:14","slug":"tanimlanmasi-zor-olan-bir-yildizin-kokeni-buyuk-patlamaya-kadar-uzaniyor","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2018\/11\/12\/tanimlanmasi-zor-olan-bir-yildizin-kokeni-buyuk-patlamaya-kadar-uzaniyor","title":{"rendered":"Tan\u0131mlanmas\u0131 zor olan bir y\u0131ld\u0131z\u0131n k\u00f6keni B\u00fcy\u00fck Patlama\u2019ya kadar uzan\u0131yor"},"content":{"rendered":"

G\u00f6kbilimciler, evrenin en eski y\u0131ld\u0131zlar\u0131ndan biri olan, neredeyse tamamen B\u00fcy\u00fck Patlama\u2019da ortaya \u00e7\u0131kan materyallerden olu\u015fan bir k\u00fctle buldular.<\/p><\/blockquote>\n

Yakla\u015f\u0131k 13,5 milyar y\u0131ll\u0131k bu minik y\u0131ld\u0131z\u0131n ke\u015ffi, \u00e7ok d\u00fc\u015f\u00fck k\u00fctleli ve \u00e7ok d\u00fc\u015f\u00fck metal i\u00e7eri\u011fine sahip daha fazla y\u0131ld\u0131z olabilece\u011fini g\u00f6steriyor – belki de evrenin ilk y\u0131ld\u0131zlar\u0131ndan baz\u0131lar\u0131.<\/p>\n

Bu y\u0131ld\u0131z s\u0131ra d\u0131\u015f\u0131, \u00e7\u00fcnk\u00fc \u00e7ok d\u00fc\u015f\u00fck metal i\u00e7eri\u011fine sahip di\u011fer y\u0131ld\u0131zlar\u0131n aksine, Samanyolu’nun “ince diski”nin bir par\u00e7as\u0131 – bizim g\u00fcne\u015fimizin bulundu\u011fu galaksinin bir par\u00e7as\u0131.<\/p>\n

Ve bu y\u0131ld\u0131z \u00e7ok eski oldu\u011fu i\u00e7in, ara\u015ft\u0131rmac\u0131lar, galaktik mevkimizin daha \u00f6nce d\u00fc\u015f\u00fcn\u00fclenden en az 3 milyar y\u0131l daha eski olabilece\u011fini s\u00f6yl\u00fcyor. Bulgular, The Astrophysical Journal<\/em>\u2019da yay\u0131mland\u0131.<\/p>\n

Makalenin ba\u015fyazar\u0131 ve Johns Hopkins \u00dcniversitesi fizik ve astronomi do\u00e7enti Kevin Schlaufman, \u015funlar\u0131 s\u00f6yl\u00fcyor: \u201cBu y\u0131ld\u0131z belki 10 milyonda birdir. Bize y\u0131ld\u0131zlar\u0131n ilk ku\u015faklar\u0131 hakk\u0131nda \u00e7ok \u00f6nemli bir \u015fey anlat\u0131yor.\u201d<\/p>\n

B\u00fcy\u00fck Patlama\u2019dan sonraki evrenin ilk y\u0131ld\u0131zlar\u0131, hidrojen, helyum ve az miktarda lityum gibi elementlerden olu\u015fmaktayd\u0131. Daha sonra bu y\u0131ld\u0131zlar \u00e7ekirdeklerinde helyumdan daha a\u011f\u0131r elementler \u00fcrettiler ve s\u00fcpernovalar olarak patlad\u0131klar\u0131nda evrene bu elementleri sa\u00e7t\u0131lar.<\/p>\n

Bu materyallerin bulutlar\u0131ndan olu\u015fan yeni nesil y\u0131ld\u0131zlar, bu metallerle ba\u011flanm\u0131\u015f ve onlar\u0131 yap\u0131lar\u0131na dahil etmi\u015ftir. Evrenin y\u0131ld\u0131zlar\u0131n\u0131n i\u00e7erdi\u011fi metal miktar\u0131, y\u0131ld\u0131z do\u011fum d\u00f6ng\u00fcs\u00fc ve \u00f6l\u00fcm\u00fc devam ettik\u00e7e artm\u0131\u015ft\u0131r.<\/p>\n

Yeni ke\u015ffedilen y\u0131ld\u0131z\u0131n son derece d\u00fc\u015f\u00fck seviyede metal i\u00e7ermesi, kozmik bir soy a\u011fac\u0131nda, B\u00fcy\u00fck Patlama\u2019dan bir nesil sonra olu\u015fmu\u015f olabilece\u011fini g\u00f6steriyor. Asl\u0131nda bu, bir y\u0131ld\u0131z\u0131n i\u00e7erdi\u011fi a\u011f\u0131r metal miktar\u0131n\u0131n azl\u0131\u011f\u0131 bak\u0131m\u0131ndan yeni bir rekor – Merk\u00fcr gezegeni ile ayn\u0131 a\u011f\u0131r element i\u00e7eri\u011fine sahip. Bunun aksine, bizim g\u00fcne\u015fimiz binlerce nesil sonras\u0131na aittir ve 14 J\u00fcpiter\u2019e e\u015fit a\u011f\u0131r bir element i\u00e7eri\u011fine sahiptir.<\/p>\n

G\u00f6kbilimciler, g\u00fcne\u015fin k\u00fctlesine yak\u0131n k\u00fctleye sahip yakla\u015f\u0131k 30 eski \u201cultra metal yoksunu\u201d y\u0131ld\u0131z ke\u015ffetti. Schlaufman ve ekibinin ke\u015ffetti\u011fi y\u0131ld\u0131z ise g\u00fcne\u015fin k\u00fctlesinin sadece y\u00fczde 14’\u00fcne e\u015fit.<\/p>\n

Y\u0131ld\u0131z, ortak bir merkez etraf\u0131nda d\u00f6nen iki y\u0131ld\u0131zl\u0131 bir sistemin par\u00e7as\u0131d\u0131r. Bir grup astronomdan olu\u015fan ekip, daha parlak “birincil” y\u0131ld\u0131z\u0131 ke\u015ffettikten sonra k\u00fc\u00e7\u00fck, neredeyse g\u00f6r\u00fcnmez soluk “ikinci” y\u0131ld\u0131z\u0131 buldu. Bu ekip \u0131\u015f\u0131\u011f\u0131n y\u00fcksek \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc bir optik spektrumunu inceleyerek birincinin bile\u015fimini \u00f6l\u00e7t\u00fc. Bir y\u0131ld\u0131z\u0131n spektrumundaki karanl\u0131k \u00e7izgilerin varl\u0131\u011f\u0131 veya yoklu\u011fu, i\u00e7erdi\u011fi karbon, oksijen, hidrojen, demir ve daha fazlas\u0131 gibi elementleri tan\u0131mlayabilir. Bu a\u00e7\u0131dan y\u0131ld\u0131z\u0131n son derece d\u00fc\u015f\u00fck metal seviyesine sahip oldu\u011fu g\u00f6r\u00fcld\u00fc. Ke\u015ffi ger\u00e7ekle\u015ftiren g\u00f6kbilimciler ayr\u0131ca y\u0131ld\u0131z sistemindeki bir n\u00f6tron y\u0131ld\u0131z\u0131na veya kara deli\u011fin varl\u0131\u011f\u0131na i\u015faret eden al\u0131\u015f\u0131lmad\u0131k davran\u0131\u015flar tespit ettiler. Schlaufman ve ekibi bir \u015feylerin yanl\u0131\u015f oldu\u011funu fark etti; ancak bunu yaparken g\u00f6r\u00fcnen y\u0131ld\u0131z\u0131n \u00e7ok daha k\u00fc\u00e7\u00fck olan yolda\u015f\u0131n\u0131 ke\u015ffettiler.<\/p>\n

Daha k\u00fc\u00e7\u00fck olan y\u0131ld\u0131z\u0131n varl\u0131\u011f\u0131 b\u00fcy\u00fck bir ke\u015fif. Schlaufman’\u0131n ekibi, k\u00fc\u00e7\u00fck y\u0131ld\u0131z\u0131n k\u00fctlesini, ana y\u0131ld\u0131z\u0131n hafif “titremesini” inceleyerek \u00e7\u0131kard\u0131.<\/p>\n

1990’lar\u0131n sonlar\u0131nda oldu\u011fu gibi, ara\u015ft\u0131rmac\u0131lar evrenin en erken a\u015famalar\u0131nda sadece b\u00fcy\u00fck y\u0131ld\u0131zlar\u0131n olu\u015fabilece\u011fine inan\u0131yorlard\u0131 – ve asla g\u00f6zlenemediler, \u00e7\u00fcnk\u00fc yak\u0131tlar\u0131n\u0131 yak\u0131p \u00e7ok \u00e7abuk \u00f6l\u00fcyorlard\u0131.<\/p>\n

Ancak astronomik sim\u00fclasyonlar daha sofistike hale geldik\u00e7e, baz\u0131 durumlarda, bu zaman diliminden, \u00f6zellikle d\u00fc\u015f\u00fck k\u00fctleli bir y\u0131ld\u0131z\u0131n, B\u00fcy\u00fck Patlama\u2019dan bu yana 13 milyar y\u0131ldan fazla bir s\u00fcre bile var olabilece\u011fine i\u015faret etmeye ba\u015flad\u0131lar. B\u00fcy\u00fck y\u0131ld\u0131zlardan farkl\u0131 olarak, d\u00fc\u015f\u00fck k\u00fctleli olanlar \u00e7ok uzun s\u00fcreler boyunca ya\u015fayabilirler. \u00d6rne\u011fin k\u0131rm\u0131z\u0131 c\u00fcce y\u0131ld\u0131zlar\u0131n g\u00fcne\u015f k\u00fctlesinin bir k\u0131sm\u0131yla birlikte trilyonlarca y\u0131l ya\u015fad\u0131klar\u0131 d\u00fc\u015f\u00fcn\u00fclmektedir.<\/p>\n

2MASS J18082002-5104378 B ad\u0131 verilen bu yeni ultra metal yoksunu y\u0131ld\u0131z\u0131n ke\u015ffi, daha eski y\u0131ld\u0131zlar\u0131 g\u00f6zlemleme olas\u0131l\u0131\u011f\u0131n\u0131 art\u0131r\u0131yor.<\/p>\n

\u00dcniversitenin Veri M\u00fchendisli\u011fi ve Bilim Enstit\u00fcs\u00fc departman\u0131 ile de ba\u011flant\u0131l\u0131 olan Schlaufman \u015funlar\u0131 s\u00f6yl\u00fcyor: \u201cE\u011fer \u00e7\u0131kar\u0131m\u0131m\u0131z do\u011fruysa, o zaman B\u00fcy\u00fck Patlama\u2019n\u0131n sonucunda olu\u015fmu\u015f olan d\u00fc\u015f\u00fck k\u00fctleli y\u0131ld\u0131zlar; g\u00f6kadam\u0131zda hen\u00fcz b\u00f6yle bir nesne bulamam\u0131\u015f olsak da var olabilir.\u201d<\/p>\n

Kaynak:<\/strong> “Elusive star has origins close to Big Bang”<\/a>, Sciencedaily<\/em>, 5 Kas\u0131m 2018.<\/p>\n","protected":false},"excerpt":{"rendered":"

G\u00f6kbilimciler, evrenin en eski y\u0131ld\u0131zlar\u0131ndan biri olan, neredeyse tamamen B\u00fcy\u00fck Patlama\u2019da ortaya \u00e7\u0131kan materyallerden olu\u015fan bir k\u00fctle buldular. Yakla\u015f\u0131k 13,5 milyar y\u0131ll\u0131k bu minik y\u0131ld\u0131z\u0131n ke\u015ffi, \u00e7ok d\u00fc\u015f\u00fck k\u00fctleli ve \u00e7ok d\u00fc\u015f\u00fck metal i\u00e7eri\u011fine sahip daha fazla y\u0131ld\u0131z olabilece\u011fini g\u00f6steriyor – belki de evrenin ilk y\u0131ld\u0131zlar\u0131ndan baz\u0131lar\u0131. Bu y\u0131ld\u0131z s\u0131ra d\u0131\u015f\u0131, \u00e7\u00fcnk\u00fc \u00e7ok d\u00fc\u015f\u00fck metal […]<\/p>\n","protected":false},"author":383,"featured_media":30782,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[30,19,26],"tags":[247,248,264,288,2000,1780],"class_list":["post-30781","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-astronomi","category-bilim-gundemi","category-fizik","tag-astrofizik","tag-astronomi","tag-buyuk-patlama","tag-fizik","tag-gokbilim","tag-yildiz"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t