Hangi elementin ne kadar bollukta bir y\u0131ld\u0131zda var oldu\u011funu anlamak, ara\u015ft\u0131rmac\u0131lar\u0131n y\u0131ld\u0131z\u0131n etraf\u0131nda dolanan gezegenlerinin D\u00fcnya’ya ne kadar benzedi\u011fini tahmin etmelerine yard\u0131mc\u0131 olabilir.<\/p>\n
Ge\u00e7en y\u0131l bu \u00f6l\u00e7\u00fcmleri yapmak i\u00e7in bir teknik geli\u015ftiren, \u00e7al\u0131\u015fman\u0131n ba\u015fyazar\u0131 Souto, “Yak\u0131n zamana kadar, bu t\u00fcr bir y\u0131ld\u0131z i\u00e7in ayr\u0131nt\u0131l\u0131 kimyasal bolluk elde etmek zordu.” dedi.<\/p>\n
\u00d6tegezegenin ev sahibi y\u0131ld\u0131z\u0131 Ross 128 gibi, Samanyolu’ndaki y\u0131ld\u0131zlar\u0131n yakla\u015f\u0131k y\u00fczde 70’i G\u00fcne\u015f’imizden \u00e7ok daha so\u011fuk ve k\u00fc\u00e7\u00fck olan k\u0131rm\u0131z\u0131 c\u00fccelerden olu\u015fmakta. B\u00fcy\u00fck gezegen arama taramalar\u0131ndan elde edilen sonu\u00e7lara dayanarak, astronomlar bu k\u0131rm\u0131z\u0131 c\u00fcce y\u0131ld\u0131zlar\u0131n\u0131n \u00e7o\u011funun en az bir \u00f6tegezegene ev sahipli\u011fi yapt\u0131\u011f\u0131n\u0131 tahmin etmekte. Son y\u0131llarda ke\u015ffetti\u011fimiz k\u0131rm\u0131z\u0131 c\u00fccelerin etraf\u0131nda yer alan gezegen sistemi (Proxima Centauri y\u0131ld\u0131z\u0131n\u0131n etraf\u0131nda dolanan Proxima b ve toplamda yedi gezegene ev sahipli\u011fi yapan TRAPPIST-1 y\u0131ld\u0131z sistemi gibi) J\u00fcpiteri\u2019den \u00e7ok da b\u00fcy\u00fck olmayan y\u0131ld\u0131zlar\u0131n etraf\u0131nda dolanan gezegenlerden olu\u015fmakta.<\/p>\n
D\u00fcnya’n\u0131n ikizine do\u011fru<\/strong><\/p>\n Ekip, elektromanyetik tayf\u0131n yak\u0131n k\u0131z\u0131l \u00f6te b\u00f6lgesinde analiz yapabilmek i\u00e7in Sloan Dijital G\u00f6ky\u00fcz\u00fc Taramas\u0131 (Sloan Digital Sky Survey, SDSS)’n\u0131n APOGEE spektroskopik aletini kullanarak, karbon, oksijen, magnezyum, al\u00fcminyum, potasyum, kalsiyum, titanyum ve demir bolluklar\u0131n\u0131 \u00f6l\u00e7t\u00fc.<\/p>\n Teske, “APOGEE’nin, Ross 128’in en parlak oldu\u011fu yak\u0131n k\u0131z\u0131l\u00f6tesinde g\u00f6zlem yapabiliyor olu\u015fu bu \u00e7al\u0131\u015fman\u0131n anahtar\u0131yd\u0131. Bu \u00f6l\u00e7\u00fcmler, Ross 128b’nin D\u00fcnya ile benzerli\u011fi hakk\u0131ndaki baz\u0131 temel sorular\u0131 yan\u0131tlamam\u0131za izin verdi\u201d dedi. Ross 128b’nin temel \u00f6zellikleri Ekip, Ross 128’deki demir miktar\u0131n\u0131n G\u00fcne\u015f’imiz ile benzer oranda oldu\u011funu tespit ettiler. Silikonun bollu\u011funu \u00f6l\u00e7ememi\u015f olmalar\u0131na ra\u011fmen, y\u0131ld\u0131zdaki demir ve magnezyum oran\u0131ndan yola \u00e7\u0131karak Ross 128b gezegeninin \u00e7ekirde\u011finin D\u00fcnya’n\u0131nkinden daha b\u00fcy\u00fck olmas\u0131 gerekti\u011fi sonucuna vard\u0131lar.<\/p>\n Ekip, Ross 128b’nin minimum k\u00fctlesini ve y\u0131ld\u0131z\u0131n\u0131n element bollu\u011funu bildi\u011fi i\u00e7in, ayr\u0131ca gezegenin yar\u0131\u00e7ap\u0131 i\u00e7in bir tahminde bulunabildi. Bu \u00f6l\u00e7\u00fcm\u00fcn b\u00f6yle yap\u0131lm\u0131\u015f olmas\u0131n\u0131n nedeni, gezegenin y\u00f6r\u00fcngesinin y\u0131ld\u0131z\u0131n etraf\u0131na y\u00f6nelmi\u015f olmas\u0131ndan dolay\u0131 do\u011frudan \u00f6l\u00e7\u00fcm yap\u0131labilmesinin m\u00fcmk\u00fcn olamay\u0131\u015f\u0131yd\u0131. Ross 128b\u2019nin tahmini yar\u0131\u00e7ap\u0131, bu gezegenin yakla\u015f\u0131k D\u00fcnya boyutlar\u0131nda ve kayal\u0131k olmas\u0131 gerekti\u011fini g\u00f6stermekte.<\/p>\n Son olarak ekip, Ross 128’in s\u0131cakl\u0131\u011f\u0131n\u0131 \u00f6l\u00e7erek ve gezegenin yar\u0131\u00e7ap\u0131n\u0131 tahmin ederek, gezegenin y\u0131ld\u0131z\u0131n\u0131n \u0131\u015f\u0131\u011f\u0131n\u0131n ne kadar\u0131n\u0131n Ross 128b y\u00fczeyinden yans\u0131taca\u011f\u0131n\u0131 belirleyebildi (\u00c7N: bir cismin ne kadar \u0131\u015f\u0131k yans\u0131tabildi\u011fine \u201cAlbedo\u201d deniyor) ve b\u00f6ylelikle ikinci en yak\u0131n kayal\u0131k kom\u015fumuzun muhtemelen \u0131l\u0131man bir iklime sahip oldu\u011funu g\u00f6sterdiler.<\/p>\n Souto, “Ev sahibi y\u0131ld\u0131z\u0131n \u0131\u015f\u0131\u011f\u0131n\u0131 kullanarak, bu \u0131\u015f\u0131\u011f\u0131n gezegenin kimyas\u0131 hakk\u0131nda bizlere neler s\u00f6yledi\u011fini \u00f6\u011frenmek son derece heyecan verici. Ross 128b, D\u00fcnya’n\u0131n tam anlam\u0131yla ikizi olmasa da hala gezegenin potansiyel jeolojik aktivitesi hakk\u0131nda bilgi sahibi de\u011filiz. Ancak, y\u00fczeyinde muhtemelen s\u0131v\u0131 su olabilecek \u0131l\u0131man bir gezegen oldu\u011fu iddias\u0131n\u0131 g\u00fc\u00e7lendirebildik\u201d diyerek s\u00f6zlerini bitirdi.<\/p>\n","protected":false},"excerpt":{"rendered":" Hangi elementin ne kadar bollukta bir y\u0131ld\u0131zda var oldu\u011funu anlamak, ara\u015ft\u0131rmac\u0131lar\u0131n y\u0131ld\u0131z\u0131n etraf\u0131nda dolanan gezegenlerinin D\u00fcnya’ya ne kadar benzedi\u011fini tahmin etmelerine yard\u0131mc\u0131 olabilir. Ge\u00e7en y\u0131l bu \u00f6l\u00e7\u00fcmleri yapmak i\u00e7in bir teknik geli\u015ftiren, \u00e7al\u0131\u015fman\u0131n ba\u015fyazar\u0131 Souto, “Yak\u0131n zamana kadar, bu t\u00fcr bir y\u0131ld\u0131z i\u00e7in ayr\u0131nt\u0131l\u0131 kimyasal bolluk elde etmek zordu.” dedi. \u00d6tegezegenin ev sahibi y\u0131ld\u0131z\u0131 Ross […]<\/p>\n","protected":false},"author":1453,"featured_media":27653,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[30,19,1],"tags":[3688,3282,3690,3692,3691,3689,3687],"class_list":["post-27645","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-astronomi","category-bilim-gundemi","category-genel","tag-dunya-benzeri-gezegen","tag-otegezegen","tag-proxima-centauri","tag-spektroskopi","tag-tayf-bilim","tag-trappist-1","tag-yer-benzeri-gezegen"],"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
\nY\u0131ld\u0131zlar gen\u00e7ken, kayal\u0131k gezegenlerden olu\u015fan h\u0131zla d\u00f6nen bir gaz ve toz diskiyle \u00e7evrilidir. Y\u0131ld\u0131z\u0131n kimyas\u0131, diskin i\u00e7eri\u011fini ve sonu\u00e7ta ortaya \u00e7\u0131kan gezegenin mineralojisini ve i\u00e7 yap\u0131s\u0131n\u0131 etkileyebilmektedir. \u00d6rne\u011fin, bir gezegendeki magnezyum, demir ve silikon miktar\u0131, i\u00e7 \u00e7ekirdek ve manto katmanlar\u0131n\u0131n k\u00fctle oran\u0131n\u0131 kontrol edecektir.<\/p>\n
\n<\/strong><\/p>\n
\nBir gezegenin k\u00fctlesini ve yar\u0131\u00e7ap\u0131n\u0131 bilmek, nelerden yap\u0131lm\u0131\u015f oldu\u011funu anlamak i\u00e7in \u00e7ok \u00f6nemlidir. \u00c7\u00fcnk\u00fc bu iki \u00f6l\u00e7\u00fcm, y\u0131\u011f\u0131lma yo\u011funlu\u011funu hesaplamak i\u00e7in kullan\u0131labilir. Dahas\u0131, g\u00f6kbilimciler bu \u00f6l\u00e7\u00fcmler sayesinde, D\u00fcnya’n\u0131n yakla\u015f\u0131k 1,7 kat\u0131ndan daha b\u00fcy\u00fck yar\u0131\u00e7apl\u0131 gezegenlerin muhtemelen Nept\u00fcn gibi gaz\u0131ms\u0131 bir katman taraf\u0131ndan \u00e7epe\u00e7evre sar\u0131nm\u0131\u015f oldu\u011funu, daha k\u00fc\u00e7\u00fck k\u00fctleye sahip olanlar\u0131n ise t\u0131pk\u0131 evimiz D\u00fcnya gibi daha kayal\u0131k bir yap\u0131ya sahip oldu\u011funu fark ettiler.<\/p>\n