2022 y\u0131l\u0131nda Mali\u2019deki Sahra \u00c7\u00f6l\u00fc\u2019nde bulunan pembe renkli bir ta\u015f\u0131n, Mars\u2019tan kopup D\u00fcnya\u2019ya ula\u015fm\u0131\u015f son derece eski bir g\u00f6kta\u015f\u0131 oldu\u011fu belirlendi. Teghaza 001 ad\u0131 verilen \u00f6rnek, yakla\u015f\u0131k 4,1 milyar y\u0131l \u00f6nce Mars\u2019ta suyun kaya\u00e7larla etkile\u015fime girdi\u011fine dair \u00f6nemli izler ta\u015f\u0131yor. Ta\u015f\u0131n ya\u015f\u0131 ve mineral yap\u0131s\u0131na ili\u015fkin ayr\u0131nt\u0131l\u0131 ara\u015ft\u0131rma 29 Ekim\u2019de Science<\/i> dergisinde yay\u0131mland\u0131. Bulgular, Mars\u2019\u0131n erken d\u00f6nem jeolojik ko\u015fullar\u0131n\u0131 ve gezegenin suyunu ne zaman kaybetmeye ba\u015flad\u0131\u011f\u0131n\u0131 anlamaya yard\u0131mc\u0131 oluyor.<\/p>\n
Teghaza 001\u2019in \u00f6nemi yaln\u0131zca ya\u015f\u0131ndan kaynaklanm\u0131yor. G\u00f6kta\u015f\u0131, farkl\u0131 volkanik mineralleri ve suyla de\u011fi\u015fime u\u011fram\u0131\u015f malzemeleri bir arada bar\u0131nd\u0131r\u0131yor. Bu \u00f6zellikler, Mars kabu\u011funun nas\u0131l olu\u015ftu\u011fu ve yer alt\u0131ndaki suyun kayalar\u0131 nas\u0131l d\u00f6n\u00fc\u015ft\u00fcrd\u00fc\u011f\u00fc konusunda bilim insanlar\u0131na do\u011frudan inceleyebilecekleri bir \u00f6rnek sunuyor. D\u00fcnya\u2019dan Mars\u2019a gidip \u00f6rnek toplamak yerine Mars\u2019tan do\u011fal yollarla koparak D\u00fcnya\u2019ya ula\u015fm\u0131\u015f bu ta\u015f, gezegenin uzak ge\u00e7mi\u015fine a\u00e7\u0131lan nadir bir pencere niteli\u011finde.<\/p>\n
Yakla\u015f\u0131k 800 gram a\u011f\u0131rl\u0131\u011f\u0131ndaki Teghaza 001, ke\u015ffedildi\u011fi Mali\u2019deki Teghaza tuz d\u00fczl\u00fc\u011f\u00fcn\u00fcn ad\u0131n\u0131 ta\u015f\u0131yor. G\u00f6kta\u015f\u0131 sekiz par\u00e7aya ayr\u0131lm\u0131\u015f durumda; en b\u00fcy\u00fck par\u00e7as\u0131 yakla\u015f\u0131k 442 gram a\u011f\u0131rl\u0131\u011f\u0131nda. Ta\u015f\u0131n Mars\u2019tan geldi\u011fi, New Mexico \u00dcniversitesi ara\u015ft\u0131rmac\u0131lar\u0131n\u0131n yapt\u0131\u011f\u0131 oksijen izotopu \u00f6l\u00e7\u00fcmleriyle do\u011fruland\u0131.<\/p>\n
\u0130zotoplar, ayn\u0131 elementin farkl\u0131 k\u00fctlelere sahip bi\u00e7imleridir. G\u00f6k cisimlerinin olu\u015fum ve evrim s\u00fcre\u00e7leri izotop oranlar\u0131nda kendilerine \u00f6zg\u00fc izler b\u0131rakabilir. Teghaza 001\u2019in oksijen izotopu de\u011ferlerinin di\u011fer Mars g\u00f6kta\u015flar\u0131yla \u00f6rt\u00fc\u015fmesi, ta\u015f\u0131n k\u00f6kenini belirlemeye yard\u0131mc\u0131 oldu. Bu t\u00fcr \u00f6l\u00e7\u00fcmler tek ba\u015f\u0131na g\u00f6kta\u015f\u0131n\u0131n Mars\u2019taki kesin konumunu g\u00f6stermez; ancak \u00f6rne\u011fin hangi gezegenden geldi\u011fini saptamak i\u00e7in g\u00fc\u00e7l\u00fc bir kimyasal parmak izi sa\u011flar.<\/p>\n
NASA\u2019n\u0131n kay\u0131tlar\u0131na g\u00f6re D\u00fcnya\u2019da Mars k\u00f6kenli oldu\u011fu bilinen yakla\u015f\u0131k 435 g\u00f6kta\u015f\u0131 bulunuyor. Bu kayalar, genellikle b\u00fcy\u00fck bir asteroidin ya da ba\u015fka bir cismin Mars y\u00fczeyine \u00e7arpmas\u0131 s\u0131ras\u0131nda uzaya f\u0131rlat\u0131lan par\u00e7alardan olu\u015fuyor. Uzayda uzun s\u00fcre yol alan par\u00e7alar\u0131n bir b\u00f6l\u00fcm\u00fc D\u00fcnya\u2019n\u0131n atmosferine girerek yery\u00fcz\u00fcne d\u00fc\u015f\u00fcyor. \u00c7\u00f6l ve karla kapl\u0131 geni\u015f alanlar, koyu ya da al\u0131\u015f\u0131lmad\u0131k renkli ta\u015flar\u0131n \u00e7evrelerinden daha kolay ay\u0131rt edilebilmesi nedeniyle bu t\u00fcr \u00f6rneklerin bulunabildi\u011fi yerler aras\u0131nda.<\/p>\n
NASA\u2019n\u0131n Jet \u0130tki Laboratuvar\u0131\u2019ndan Yang Liu\u2019nun liderlik etti\u011fi ara\u015ft\u0131rma ekibi, Teghaza 001\u2019in i\u00e7inde zirkon kristalleri tespit etti. Zirkon, olu\u015ftu\u011fu s\u0131rada baz\u0131 radyoaktif elementleri b\u00fcnyesine al\u0131p zamanla de\u011fi\u015fen \u00f6l\u00e7\u00fclebilir izler b\u0131rakabildi\u011fi i\u00e7in kaya\u00e7lar\u0131n ya\u015f\u0131n\u0131 belirlemede \u00f6zellikle yararl\u0131 bir mineraldir. Kristallerin kimyasal bile\u015fimi ve izotoplar\u0131 incelenerek kayan\u0131n ne zaman olu\u015ftu\u011fu ve daha sonra hangi jeolojik s\u00fcre\u00e7lerden ge\u00e7ti\u011fi hakk\u0131nda bilgi edinilebilir.<\/p>\n
Caltech\u2019ten Francois Tissot\u2019nun ekibi, ta\u015f\u0131n ya\u015f\u0131n\u0131 \u00f6l\u00e7mek i\u00e7in \u00e7ok k\u00fc\u00e7\u00fck bir \u00f6rnek \u00fczerinde mineral tanelerini ayr\u0131 ayr\u0131 inceleyen bir y\u00f6ntem kulland\u0131. T\u0131rnaktan k\u00fc\u00e7\u00fck bir par\u00e7ayla yap\u0131lan bu analiz, nadir g\u00f6kta\u015f\u0131n\u0131n b\u00fcy\u00fck b\u00f6l\u00fcm\u00fcn\u00fc korumaya imk\u00e2n verdi. Bu yakla\u015f\u0131m \u00f6nemlidir; \u00e7\u00fcnk\u00fc \u00f6rne\u011fin farkl\u0131 par\u00e7alar\u0131 ileride ba\u015fka ara\u015ft\u0131rma sorular\u0131n\u0131 yan\u0131tlamak i\u00e7in kullan\u0131labilir.<\/p>\n
Analizler, Teghaza 001\u2019in yakla\u015f\u0131k 4,1 milyar y\u0131l \u00f6nce suyla etkile\u015fime girerek de\u011fi\u015fime u\u011frad\u0131\u011f\u0131n\u0131 g\u00f6steriyor. Bu tarih, kayan\u0131n mutlaka tam o s\u0131rada ilk kez olu\u015ftu\u011fu anlam\u0131na gelmiyor. Aksine, suyun kaya\u00e7 \u00fczerinde b\u0131rakt\u0131\u011f\u0131 de\u011fi\u015fimin ya\u015f\u0131 yakla\u015f\u0131k 4,1 milyar y\u0131l olarak belirlenmi\u015f durumda; kayan\u0131n ba\u015flang\u0131\u00e7taki olu\u015fumu bu olaydan daha eski olabilir. Dolay\u0131s\u0131yla g\u00f6kta\u015f\u0131, Mars\u2019\u0131n erken tarihinde hem kaya olu\u015fumuna hem de sonradan ya\u015fanan su-kaya etkile\u015fimine dair kay\u0131t ta\u015f\u0131yor.<\/p>\n
Teghaza 001\u2019in oksijen izotopu oranlar\u0131, incelenen di\u011fer Mars g\u00f6kta\u015flar\u0131n\u0131n \u00e7o\u011funa k\u0131yasla belirgin bi\u00e7imde y\u00fcksek. Ara\u015ft\u0131rmac\u0131lar bu fark\u0131, magman\u0131n Mars y\u00fczeyinde veya y\u00fczeye yak\u0131n b\u00f6lgelerde suyla etkile\u015fmi\u015f kabuk malzemesiyle kar\u0131\u015fm\u0131\u015f olabilece\u011fi \u015feklinde yorumluyor. Ba\u015fka bir deyi\u015fle ta\u015f\u0131n bile\u015fimi, yaln\u0131zca erimi\u015f kayalar\u0131n so\u011fumas\u0131n\u0131 de\u011fil, suyun bu kaya\u00e7lar\u0131n kimyas\u0131n\u0131 de\u011fi\u015ftirmi\u015f olabilece\u011fini de yans\u0131t\u0131yor.<\/p>\n
Bu t\u00fcr kan\u0131tlar, Mars\u2019ta bir zamanlar su bulundu\u011funu g\u00f6steren genel tabloya yeni ayr\u0131nt\u0131lar ekliyor. Su, kaya\u00e7lar\u0131n i\u00e7indeki mineralleri d\u00f6n\u00fc\u015ft\u00fcrebilir ve elementlerin da\u011f\u0131l\u0131m\u0131n\u0131 de\u011fi\u015ftirebilir. Bu de\u011fi\u015fikliklerin ta\u015f i\u00e7inde korunmas\u0131, milyarlarca y\u0131l \u00f6nceki \u00e7evre ko\u015fullar\u0131n\u0131 bug\u00fcne ta\u015f\u0131r. \u00c7al\u0131\u015fman\u0131n ekip \u00fcyelerinden Lee Saper, \u00f6rne\u011fi Mars\u2019\u0131n daha \u00f6nce do\u011frudan \u00f6rne\u011fi bulunmayan bir b\u00f6lgesinden gelen kabuk par\u00e7as\u0131 olarak nitelendirdi. Ara\u015ft\u0131rmac\u0131 Yang Liu da makalenin hakemlerinden birinin g\u00f6kta\u015f\u0131n\u0131 Mars i\u00e7in \u201cRosetta Ta\u015f\u0131\u201dna benzetti\u011fini aktard\u0131. Bu benzetme, ta\u015f\u0131n farkl\u0131 jeolojik s\u00fcre\u00e7leri \u00e7\u00f6z\u00fcmlemeye yard\u0131mc\u0131 olabilecek bilgi ta\u015f\u0131mas\u0131na dayan\u0131yor; Mars\u2019\u0131n t\u00fcm ge\u00e7mi\u015fini tek ba\u015f\u0131na a\u00e7\u0131klayaca\u011f\u0131 anlam\u0131na gelmiyor.<\/p>\n
Teghaza 001\u2019deki suyun ge\u00e7mi\u015fine ili\u015fkin ba\u015fka bir ara\u015ft\u0131rma ayr\u0131nt\u0131s\u0131, haziran ay\u0131nda Science Advances<\/i> dergisinde yay\u0131mland\u0131. Bilim insanlar\u0131, ta\u015f\u0131n fosfat kristallerinde hapsolmu\u015f suyu inceleyerek hidrojenin a\u011f\u0131r izotopu olan d\u00f6teryumun oran\u0131n\u0131 \u00f6l\u00e7t\u00fc. Sonu\u00e7lar, yakla\u015f\u0131k 4,1 milyar y\u0131l \u00f6nce Mars\u2019taki suyun d\u00f6teryum oran\u0131n\u0131n D\u00fcnya deniz suyundakinin en az iki kat\u0131 olabilece\u011fine i\u015faret etti.<\/p>\n
Bu oran, gezegenlerin atmosfer ve su kayb\u0131 s\u00fcre\u00e7lerini anlamada \u00f6nemlidir. Hidrojenin hafif izotopu, atmosferin \u00fcst katmanlar\u0131ndan uzaya ka\u00e7maya d\u00f6teryuma g\u00f6re daha yatk\u0131nd\u0131r. Zaman i\u00e7inde hafif hidrojenin daha b\u00fcy\u00fck b\u00f6l\u00fcm\u00fcn\u00fcn kaybedilmesi, geride kalan suyun d\u00f6teryum bak\u0131m\u0131ndan zenginle\u015fmesine yol a\u00e7abilir. Bu nedenle Teghaza 001\u2019de \u00f6l\u00e7\u00fclen y\u00fcksek d\u00f6teryum oran\u0131, Mars\u2019\u0131n su kayb\u0131n\u0131n 4,1 milyar y\u0131l \u00f6nce ba\u015flam\u0131\u015f olabilece\u011fini d\u00fc\u015f\u00fcnd\u00fcr\u00fcyor.<\/p>\n
Bu bulgu, Mars\u2019\u0131n bir d\u00f6nem daha s\u0131cak ve su bak\u0131m\u0131ndan daha zengin ko\u015fullara sahip oldu\u011fu d\u00fc\u015f\u00fcncesiyle uyumlu. Ancak tek bir g\u00f6kta\u015f\u0131 b\u00fct\u00fcn gezegenin suyunun ne kadar\u0131n\u0131, hangi h\u0131zla ve hangi b\u00f6lgelerde kaybetti\u011fini tek ba\u015f\u0131na belirleyemez. D\u00f6teryum \u00f6l\u00e7\u00fcm\u00fc, izotop oranlar\u0131 ve mineral yap\u0131s\u0131 gibi farkl\u0131 kan\u0131tlarla birlikte de\u011ferlendirilerek Mars\u2019\u0131n iklim ve atmosfer tarihine ili\u015fkin daha kapsaml\u0131 bir tablo olu\u015fturuluyor.<\/p>\n
Teghaza 001\u2019in Mars y\u00fczeyinde tam olarak hangi noktadan koptu\u011fu bilinmiyor. Bir g\u00f6kta\u015f\u0131n\u0131n kimyasal ve mineral bile\u015fimi, belirli bir b\u00f6lgeyle e\u015fle\u015ftirme yap\u0131lmas\u0131na yard\u0131mc\u0131 olabilir; ancak uzayda ge\u00e7irdi\u011fi yolculuk ve Mars\u2019tan f\u0131rlat\u0131lma ko\u015fullar\u0131 kesin k\u00f6keni belirlemeyi zorla\u015ft\u0131r\u0131yor. Ara\u015ft\u0131rmac\u0131lar, ta\u015f\u0131n mineral yap\u0131s\u0131n\u0131 NASA\u2019n\u0131n Mars Reconnaissance Orbiter arac\u0131n\u0131n gezegenin g\u00fcney yaylalar\u0131nda g\u00f6zlemledi\u011fi jeolojik \u00f6zelliklerle kar\u015f\u0131la\u015ft\u0131rd\u0131.<\/p>\n
Bu kar\u015f\u0131la\u015ft\u0131rma sonucunda, g\u00f6kta\u015f\u0131n\u0131n bile\u015fimiyle uyu\u015fabilecek 13 olas\u0131 b\u00f6lge belirlendi. Bunlar kesin ini\u015f ya da kopu\u015f noktalar\u0131 de\u011fil, mevcut mineral ve kimyasal verilere dayanan aday alanlar. Mars y\u00f6r\u00fcngesindeki ara\u00e7lardan elde edilen g\u00f6r\u00fcnt\u00fcler ve y\u00fczey \u00f6l\u00e7\u00fcmleri, g\u00f6kta\u015f\u0131ndaki \u00f6zelliklerin gezegenin hangi t\u00fcr b\u00f6lgelerinde bulunabilece\u011fini daraltmaya yard\u0131mc\u0131 oluyor. Daha kesin bir e\u015fle\u015ftirme i\u00e7in Mars y\u00fczeyinden al\u0131nm\u0131\u015f ve konumu bilinen \u00f6rneklerin incelenmesi b\u00fcy\u00fck \u00f6nem ta\u015f\u0131yor.<\/p>\n
Teghaza 001, D\u00fcnya\u2019da bulunan en eski \u00fc\u00e7 Mars g\u00f6kta\u015f\u0131ndan biri olarak de\u011ferlendiriliyor. Benzer ya\u015fta oldu\u011fu bilinen ALH84001 adl\u0131 g\u00f6kta\u015f\u0131 b\u00fcy\u00fck \u00f6l\u00e7\u00fcde tek bir mineral t\u00fcr\u00fcnden olu\u015furken Teghaza 001\u2019de farkl\u0131 volkanik mineraller bir arada bulunuyor. Bu \u00e7e\u015fitlilik, kayan\u0131n tek bir basit olu\u015fum olay\u0131ndan ibaret olmad\u0131\u011f\u0131n\u0131 ve farkl\u0131 s\u00fcre\u00e7lerin izlerini koruyabildi\u011fini g\u00f6steriyor.<\/p>\n
Minerallerin birlikte incelenmesi, Mars kabu\u011funun so\u011fuyan magmadan nas\u0131l meydana geldi\u011fini ve daha sonra yer alt\u0131 suyunun bu kabu\u011fu nas\u0131l de\u011fi\u015ftirdi\u011fini anlamaya yard\u0131mc\u0131 olabilir. Bir mineral olu\u015fum s\u0131ras\u0131nda, di\u011feri ise suyla etkile\u015fim sonras\u0131nda \u015fekillenmi\u015f olabilir. Bilim insanlar\u0131 bu farkl\u0131 kay\u0131tlar\u0131 kar\u015f\u0131la\u015ft\u0131rarak kaya\u00e7lar\u0131n olu\u015fum ve d\u00f6n\u00fc\u015f\u00fcm s\u0131ras\u0131n\u0131 yeniden kurmaya \u00e7al\u0131\u015f\u0131yor. Bu nedenle Teghaza 001, yaln\u0131zca ya\u015f\u0131 nedeniyle de\u011fil, i\u00e7erdi\u011fi jeolojik \u00e7e\u015fitlilik nedeniyle de bilimsel a\u00e7\u0131dan de\u011ferli.<\/p>\n
Ara\u015ft\u0131rmac\u0131lar, g\u00f6kta\u015f\u0131n\u0131n incelenmesinin hen\u00fcz ba\u015flang\u0131\u00e7 a\u015famas\u0131nda oldu\u011funu vurguluyor. Yeni \u00f6l\u00e7\u00fcmler, ta\u015f\u0131n i\u00e7indeki farkl\u0131 minerallerin hangi ko\u015fullarda olu\u015ftu\u011funu ve suyun kayayla ne kadar s\u00fcre etkile\u015fimde bulundu\u011funu daha ayr\u0131nt\u0131l\u0131 bi\u00e7imde ortaya \u00e7\u0131karabilir. Mars\u2019tan do\u011frudan \u00f6rnek getirme g\u00f6revleri ger\u00e7ekle\u015fene kadar Teghaza 001 gibi g\u00f6kta\u015flar\u0131, gezegenin ge\u00e7mi\u015fini D\u00fcnya\u2019daki laboratuvarlarda incelemek i\u00e7in s\u0131n\u0131rl\u0131 fakat son derece \u00f6nemli kaynaklar olmaya devam edecek.<\/p>\n
Teghaza 001\u2019in sa\u011flad\u0131\u011f\u0131 temel sonu\u00e7lar<\/strong><\/p>\n Ta\u015f, 2022\u2019de Mali\u2019deki Sahra \u00c7\u00f6l\u00fc\u2019nde bulundu ve oksijen izotopu \u00f6l\u00e7\u00fcmleriyle Mars k\u00f6kenli oldu\u011fu do\u011fruland\u0131.<\/p>\n<\/li>\n G\u00f6kta\u015f\u0131 yakla\u015f\u0131k 4,1 milyar y\u0131l \u00f6nce suyla etkile\u015ferek de\u011fi\u015fime u\u011frad\u0131; ilk olu\u015fum tarihi bu etkile\u015fimden daha eski olabilir.<\/p>\n<\/li>\n Y\u00fcksek oksijen izotopu oranlar\u0131, magman\u0131n suyla etkile\u015fmi\u015f Mars kabuk malzemesiyle kar\u0131\u015fm\u0131\u015f olabilece\u011fini d\u00fc\u015f\u00fcnd\u00fcr\u00fcyor.<\/p>\n<\/li>\n Fosfat kristallerindeki d\u00f6teryum \u00f6l\u00e7\u00fcmleri, Mars\u2019\u0131n suyunu \u00e7ok erken bir d\u00f6nemde kaybetmeye ba\u015flam\u0131\u015f olabilece\u011fine i\u015faret ediyor.<\/p>\n<\/li>\n G\u00f6kta\u015f\u0131n\u0131n Mars\u2019taki kesin \u00e7\u0131k\u0131\u015f noktas\u0131 bilinmiyor; mineral ve kimyasal \u00f6zellikler 13 olas\u0131 b\u00f6lgeyle uyum g\u00f6steriyor.<\/p>\n<\/li>\n<\/ul>\n\n