{"id":37662,"date":"2019-10-22T03:20:52","date_gmt":"2019-10-22T00:20:52","guid":{"rendered":"https:\/\/bilimvegelecek.com.tr\/?p=37662"},"modified":"2019-10-22T07:36:40","modified_gmt":"2019-10-22T04:36:40","slug":"yasama-elverisli-bolgede-bulunan-otegezegenlerde-yasam-gercekten-mumkun-mu","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2019\/10\/22\/yasama-elverisli-bolgede-bulunan-otegezegenlerde-yasam-gercekten-mumkun-mu","title":{"rendered":"Ya\u015fama elveri\u015fli b\u00f6lgede bulunan \u00f6tegezegenlerde ya\u015fam ger\u00e7ekten m\u00fcmk\u00fcn m\u00fc?"},"content":{"rendered":"<p>\u201cEvrende yaln\u0131z m\u0131y\u0131z?\u201d sorusundan daha merak uyand\u0131r\u0131c\u0131 pek az soru vard\u0131r. Uzayda ya\u015fama dair aray\u0131\u015f insano\u011flunun hayal g\u00fcc\u00fcn\u00fc bin y\u0131llard\u0131r me\u015fgul etmekte. Bug\u00fcn, G\u00fcne\u015f haricinde bir y\u0131ld\u0131z\u0131n etraf\u0131nda hareket eden ilk gezegenin ke\u015ffinden bu yana ge\u00e7en 25 y\u0131l\u0131n ard\u0131ndan, bu sorunun cevab\u0131n\u0131 bulmaya hi\u00e7 olmad\u0131\u011f\u0131 kadar yak\u0131n\u0131z.<\/p>\n<p>Harvard \u00dcniversitesi\u2019nden astronom David Charbonneau, \u201cHemen hemen herkes hayat\u0131n\u0131n bir noktas\u0131nda di\u011fer gezegenlerde ya\u015fam olup olmad\u0131\u011f\u0131 sorusu \u00fczerinde d\u00fc\u015f\u00fcnm\u00fc\u015ft\u00fcr. Asl\u0131nda bu sorunun cevab\u0131n\u0131 bilebilirdik\u2026 Gidip ne t\u00fcr bir teleskop in\u015fa etmemiz gerekti\u011fini biliyoruz\u201d diyor.<\/p>\n<p>Ger\u00e7i, hayat bar\u0131nd\u0131rma ihtimali en y\u00fcksek olan gezegenlerin nas\u0131l tan\u0131mlanabilece\u011fine ili\u015fkin uzun zamand\u0131r s\u00fcren tart\u0131\u015fmalar d\u00fc\u015f\u00fcn\u00fcld\u00fc\u011f\u00fcnde, bu o kadar da basit olmayabilir. 11 Eyl\u00fcl 2019\u2019da, yak\u0131nlar\u0131m\u0131zdaki \u00f6tegezegen \u2018K2 18b\u2019nin atmosferinde su buhar\u0131 bulundu\u011funa dair ke\u015ffin duyurulmas\u0131yla tart\u0131\u015fmalar zirve noktas\u0131na ula\u015ft\u0131.<\/p>\n<p>Bu gezegenin \u00e7ekicili\u011fi, y\u0131ld\u0131z\u0131n\u0131n etraf\u0131ndaki \u201cya\u015fama elveri\u015fli b\u00f6lge\u201dnin (S\u0131kl\u0131kla s\u0131cakl\u0131\u011f\u0131n ya\u015fam i\u00e7in kritik olan suyun s\u0131v\u0131 formda bulunmas\u0131na elveri\u015fli d\u00fczeyde oldu\u011fu b\u00f6lge olarak tan\u0131mlan\u0131r) i\u00e7erisindeki konumundan geliyor. Astronomlar\u0131n belirtti\u011fine g\u00f6re, K3 18b ya\u011fmur bulutlar\u0131na dahi sahip olabilir.<\/p>\n<p>Bu, tabii ki, \u015femsiyenizi kap\u0131p oraya gitmeniz gerekti\u011fi anlam\u0131na gelmiyor. Caltech ve NASA \u00d6tegezegen Bilimi Enstit\u00fcs\u00fc\u2019nden astrofizik\u00e7i Jessie Christiansen, \u201c\u00c7\u00fcnk\u00fc bir gezegenin ya\u015fama elveri\u015fli b\u00f6lgede bulunmas\u0131, onu ya\u015fanabilir yapmaz\u201d diyor ve ekliyor, \u201c100 astronoma sorsan\u0131z, 99\u2019u bu gezegenin ya\u015fama elveri\u015fli olmad\u0131\u011f\u0131n\u0131 s\u00f6yleyecektir\u201d.<\/p>\n<p>Asl\u0131nda, y\u00f6r\u00fcngesinin b\u00fcy\u00fck b\u00f6l\u00fcm\u00fcn\u00fc y\u0131ld\u0131z\u0131n\u0131n ya\u015fama elveri\u015fli b\u00f6lgesinden ge\u00e7ti\u011fi bilinen 192 gezegenden 168\u2019i y\u00fcksek ihtimalle J\u00fcpiter benzeri, hi\u00e7 de misafirperver olmayan gaz devleridir. Dahas\u0131 kayal\u0131k bir gezegen ya\u015fama elveri\u015fli b\u00f6lgede bulunsa dahi, bu bilgi o gezegende ya\u015fanabilir bir alan oldu\u011funu garanti etmez; t\u0131pk\u0131 Mars\u2019\u0131n durumu gibi. Bilim insanlar\u0131 K\u0131z\u0131l Gezegen\u2019in ya\u015fam bar\u0131nd\u0131rma ihtimalini tart\u0131\u015fmal\u0131 olarak de\u011ferlendiriyor.<\/p>\n<p><strong>S\u0131n\u0131rl\u0131 se\u00e7enekler<\/strong><br \/>\n1 Ekim 2019 itibariyle ke\u015ffi yap\u0131lm\u0131\u015f olan 4,118 \u00f6tegezegenden sadece 24\u2019\u00fc ya\u015fama elveri\u015flilik kriterini kar\u015f\u0131l\u0131yor olabilir. Bu gezegenlerin k\u00fctle ve yar\u0131\u00e7aplar\u0131 D\u00fcnya\u2019n\u0131nkine benzer kayal\u0131k bir y\u00fczeye sahip olduklar\u0131na i\u015faret ediyor ve y\u00f6r\u00fcngelerinde ge\u00e7irdikleri s\u00fcrenin \u00e7o\u011funlu\u011funda y\u0131ld\u0131zlar\u0131na olan uzakl\u0131klar\u0131 suyun s\u0131v\u0131 formda bulunmas\u0131n\u0131 destekliyor.<\/p>\n<p>1 Ekim 2019 itibariyle bilinen toplam 4,118 \u00f6tegezegenden 192\u2019si y\u00f6r\u00fcngelerinin \u00e7o\u011funda, 301\u2019i y\u00f6r\u00fcngelerinin bir k\u0131sm\u0131nda, 129\u2019u y\u00f6r\u00fcngesinin tamam\u0131nda ya\u015fama elveri\u015fli b\u00f6lgede bulunurken, 3,496 \u00f6tegezegen ise ya\u015fama elveri\u015fli b\u00f6lgenin d\u0131\u015f\u0131nda bulunuyor. Ayr\u0131ca y\u00f6r\u00fcngelerinin \u00e7o\u011funda ya\u015fama elveri\u015fli b\u00f6lgede bulunan gezegenlerden sadece 24\u2019\u00fc muhtemelen kayal\u0131k.<\/p>\n<p>\u00d6yleyse D\u00fcnya\u2019da kalm\u0131\u015fken ya\u015fama elveri\u015fli bir gezegeni nas\u0131l bulursunuz? Kulland\u0131\u011f\u0131m\u0131z terimlerin tan\u0131mlar\u0131n\u0131 tekrardan d\u00fc\u015f\u00fcnerek i\u015fe ba\u015flayal\u0131m. Baz\u0131 astronomlar, i\u00e7erisinde ya\u015fanabilme ihtimalinin hi\u00e7 olmad\u0131\u011f\u0131 gezegenleri i\u00e7ine al\u0131p, ya\u015fanabilme ihtimali olan baz\u0131lar\u0131n\u0131 d\u0131\u015far\u0131da b\u0131rakt\u0131\u011f\u0131 i\u00e7in \u201cya\u015fama elveri\u015fli b\u00f6lge\u201d ifadesini fazla kullan\u0131\u015fs\u0131z buluyor. \u00c7e\u015fitli disiplinlerden biliminsanlar\u0131 ya\u015fama elveri\u015flilik kavram\u0131n\u0131 iyile\u015ftirmek i\u00e7in mineral fizi\u011fi, kimya ve ekolojiyi mercek alt\u0131na al\u0131yor.<\/p>\n<p>Dahas\u0131 ya\u015fam\u0131 aramak i\u00e7in tasarlanm\u0131\u015f yeni uzay g\u00f6zlemevleri gelecek sene NASA taraf\u0131ndan onaylanabilir. Charbonneau\u2019ya g\u00f6re, belki de g\u00fcncellenmesi gereken sadece ya\u015fama elveri\u015flili\u011fi tan\u0131mlamak i\u00e7in kulland\u0131\u011f\u0131m\u0131z kelimeler de\u011fil, ayn\u0131 zamanda onlar\u0131 bulmak i\u00e7in kulland\u0131\u011f\u0131m\u0131z ekipmanlard\u0131r da. \u201cDo\u011fru teleskoplara sahip de\u011filiz\u201d.<\/p>\n<p><strong>Sadece T\u00fcm Gezegenler De\u011fil<\/strong><br \/>\n1950\u2019lerden bu yana, astronomlar ya\u015fama elveri\u015fli d\u00fcnyalar bulmaktan bahsetti\u011finde yo\u011funla\u015ft\u0131klar\u0131 \u015fey tamamen, D\u00fcnya\u2019ya benzer gezegenlerdi. Penn Eyalet \u00dcniversitesi\u2019nden Yerbilimci James Kasting 1993\u2019te Icarus\u2019ta yay\u0131mlanan makalesinde, \u201cya\u015fama elveri\u015fli b\u00f6lge\u201dnin, bug\u00fcn de kullan\u0131mda olan, en pop\u00fcler tan\u0131m\u0131n\u0131n temelini att\u0131. Bu b\u00f6lge s\u0131cakl\u0131\u011f\u0131n suyun s\u0131v\u0131 formda bulunabilmesi i\u00e7in ne \u00e7ok y\u00fcksek ne de \u00e7ok d\u00fc\u015f\u00fck oldu\u011fu \u201cGoldilocks\u201d b\u00f6lgesidir. Ancak bu kriter ya\u015fama elveri\u015fli b\u00f6lge i\u00e7erisinde yer alan t\u00fcm gezegenlere uygulanamaz; Kasting\u2019in modeli sadece D\u00fcnya benzeri karbon dioksit, su ve nitrojenden olu\u015fan bir atmosfere sahip kayal\u0131k gezegenler i\u00e7in \u00e7al\u0131\u015f\u0131r.<\/p>\n<figure id=\"attachment_37664\" aria-describedby=\"caption-attachment-37664\" style=\"width: 300px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-37664 size-medium\" src=\"https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim-1-300x161.jpg\" alt=\"\" width=\"300\" height=\"161\" srcset=\"https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim-1-300x160.jpg 300w, https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim-1-600x321.jpg 600w, https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim-1.jpg 680w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><figcaption id=\"caption-attachment-37664\" class=\"wp-caption-text\">\u201cYa\u015fama elveri\u015fli b\u00f6lgede her tipte gezegen bulunabilir\u201d<\/figcaption><\/figure>\n<p>JAXA\u2019dan (Japon Uzay Ara\u015ft\u0131rma Ajans\u0131) Elizabeth Tasker, \u201cYa\u015fama elveri\u015fli b\u00f6lgede her tipte gezegen bulunabilir\u201d diyor ve ancak D\u00fcnya benzeri gezegenlerin y\u00fczeyinde s\u0131v\u0131 su bulundurmas\u0131n\u0131n muhtemel oldu\u011funu s\u00f6yl\u00fcyor. Tasker\u2019a g\u00f6re, asl\u0131nda herkes bunu i\u00e7ten i\u00e7e biliyor, \u00e7\u00fcnk\u00fc ya\u015fama elveri\u015fli b\u00f6lgede bulunmalar\u0131na ra\u011fmen ne Ay ne de Mars g\u00f6l kenar\u0131 ka\u00e7ama\u011f\u0131 yap\u0131lacak yerlere sahip de\u011fil.<\/p>\n<p>1993 y\u0131l\u0131na d\u00f6nersek, o tarihte s\u0131radan bir y\u0131ld\u0131z\u0131n etraf\u0131nda d\u00f6nen bir \u00f6tegezegen hen\u00fcz bulunamam\u0131\u015ft\u0131, bir pulsar\u0131n (h\u0131zla d\u00f6nen \u00f6lm\u00fc\u015f bir y\u0131ld\u0131z) etraf\u0131nda d\u00f6nen birka\u00e7 \u00f6tegezegen biliniyordu sadece. \u201cBunun tamamen kuramsal oldu\u011funu d\u00fc\u015f\u00fcnm\u00fc\u015ft\u00fcm\u201d diyor Kasting. \u0130ki y\u0131l sonra, ara\u015ft\u0131rmac\u0131lar ilk kez G\u00fcne\u015f benzeri bir y\u0131ld\u0131z etraf\u0131nda d\u00f6nen bir gezegen ke\u015ffettiler. Bu gezegen, yani &#8220;51 Pegasi b&#8221;, s\u0131cak bir J\u00fcpiter\u2019di ve ya\u015fama elveri\u015fli b\u00f6lgede bulunmak i\u00e7in y\u0131ld\u0131z\u0131na fazla yak\u0131nd\u0131. Fakat bu ke\u015fif \u00f6tegezegen astronomisinin resmi olarak do\u011fu\u015funu i\u015faretledi. O zamandan bu yana, 4,000\u2019den fazla \u00f6tegezegen bulundu ve binlerce aday da onaylanmay\u0131 bekliyor. \u201cHer \u015fey oradan y\u00fckseli\u015fe ge\u00e7ti\u201d diyor Kasting ve ekliyor: \u201c\u015euan bu g\u00f6zlemsel bir alan, kuramsal de\u011fil\u201d.<\/p>\n<p><strong>Boyutlar ve Y\u00fczeyler<\/strong><br \/>\nBu iki anahtar \u00f6zellik \u2013kayal\u0131k bir y\u00fczey ve do\u011fru atmosferik kar\u0131\u015f\u0131m\u2013 bir y\u0131ld\u0131z\u0131n ya\u015fama elveri\u015fli b\u00f6lgesinde yeni bir d\u00fcnya bulman\u0131n heyecan\u0131 i\u00e7erisindeyken s\u0131kl\u0131kla unutulur. Ancak bunlar\u0131n bir gezegenin ger\u00e7ek ya\u015fama elveri\u015flili\u011fi a\u00e7\u0131s\u0131ndan \u00f6nemli oldu\u011funu d\u00fc\u015f\u00fcnmek i\u00e7in nedenler var.<\/p>\n<p>Harvard-Smithsonian Astrofizik Merkezi\u2019nden astronom Laura Kreidberg, e\u011fer bir gezegen fazla gazl\u0131ysa, atmosferik bas\u0131n\u00e7 ve s\u0131cakl\u0131\u011f\u0131n DNA gibi karma\u015f\u0131k molek\u00fcllerin kararl\u0131 olabilmesi i\u00e7in fazla \u015fiddetli olaca\u011f\u0131n\u0131 s\u00f6yl\u00fcyor. \u00d6rne\u011fin, hidrojence zengin kal\u0131n bir atmosferle kayal\u0131k bir \u00e7ekirde\u011fin ara y\u00fczeyinde s\u0131cakl\u0131k 2,500\u00b0 C\u2019un \u00fczerinde de\u011ferlere ula\u015fabilir. Dahas\u0131 karma\u015f\u0131k kimya \u201caritmetik \u015feytan\u201d ismiyle bilinen bir olgu taraf\u0131ndan sekteye u\u011frat\u0131labilir. Gazla dolu bir atmosferde atomlar\u0131n birbirleriyle kar\u015f\u0131la\u015f\u0131p etkile\u015fime ge\u00e7erek yeni molek\u00fcller olu\u015fturmalar\u0131 \u00e7ok uzun zaman alabilir. Kreidberg, \u201cBunlar\u0131n ikisi de bir gezegende ya\u015fam\u0131 harekete ge\u00e7iren yap\u0131ta\u015flar\u0131n\u0131n olu\u015fmas\u0131 a\u00e7\u0131s\u0131ndan ger\u00e7ekten k\u00f6t\u00fc haberler\u201d diyor.<\/p>\n<p>K2 18b ile ilgili problemin bir b\u00f6l\u00fcm\u00fc, onun kayal\u0131k bir y\u00fczeye sahip olup olmad\u0131\u011f\u0131n\u0131n net olmamas\u0131d\u0131r. Bir \u00f6tegezegenin nelerden meydana geldi\u011fini s\u00f6ylemenin tek yolu, \u2013y\u0131ld\u0131z\u0131n\u0131n \u00f6n\u00fcnden ge\u00e7erken kesti\u011fi \u0131\u015f\u0131\u011f\u0131n miktar\u0131na bakarak\u2013 onun yar\u0131\u00e7ap\u0131n\u0131 ve \u2013y\u0131ld\u0131z\u0131na uygulad\u0131\u011f\u0131 k\u00fctle\u00e7ekimsel s\u00fcr\u00fcklemeye bakarak\u2013 k\u00fctlesini \u00f6l\u00e7mektir. K\u00fctle ve yar\u0131\u00e7ap birlikte gezegenin bile\u015fimi i\u00e7in bir ipucu olan yo\u011funlu\u011fu bize s\u00f6yler. Ancak astronomlar her zaman ikisini birden \u00f6l\u00e7emezler.<\/p>\n<p>Astronomlar\u0131n K2 18b ile \u015fans\u0131 yaver gitti; gezegenin k\u00fctlesi D\u00fcnya\u2019n\u0131nkinin yakla\u015f\u0131k sekiz kat\u0131, yar\u0131\u00e7ap\u0131 ise D\u00fcnya\u2019n\u0131nkinin iki kat\u0131ndan fazla olarak \u00f6l\u00e7\u00fcmlendi. Bunun anlam\u0131, gezegen Mars\u2019\u0131nkine benzer bir yo\u011funlu\u011fa sahip. K2 18b\u2019nin atmosferinde su bulan ekip gezegenin karasal ve kayal\u0131k olabilece\u011fini d\u00fc\u015f\u00fcnse de, di\u011fer ara\u015ft\u0131rmac\u0131lar bundan o kadar emin de\u011fil.<\/p>\n<p>K\u00fc\u00e7\u00fck gezegenler iki gruba ayr\u0131lmaya meyillidir; kayal\u0131k s\u00fcper-D\u00fcnyalar ve gazla dolu mini-Nept\u00fcnler. G\u00f6r\u00fcn\u00fc\u015fe g\u00f6re, yar\u0131\u00e7ap\u0131 D\u00fcnya\u2019n\u0131n yar\u0131\u00e7ap\u0131n\u0131n 1.5 kat\u0131ndan k\u00fc\u00e7\u00fck olan gezegenler kayal\u0131k, bu de\u011fere yak\u0131n ve b\u00fcy\u00fck olanlar ise \u00e7o\u011funlukla mini-Nept\u00fcnler olarak s\u0131n\u0131fland\u0131r\u0131l\u0131r. K2 18b\u2019nin yar\u0131\u00e7ap\u0131 bu de\u011ferden \u00e7ok daha b\u00fcy\u00fckt\u00fcr.<\/p>\n<p>K\u00fc\u00e7\u00fck gezegenler iki gruba ayr\u0131l\u0131yor gibi g\u00f6r\u00fcn\u00fcyor; kayal\u0131k s\u00fcper-D\u00fcnyalar ve gazla dolu mini-Nept\u00fcnler. Astronom gezegenlerin hangi s\u0131n\u0131fa ait olduklar\u0131n\u0131 onlar\u0131n k\u00fctle ve boyutlar\u0131n\u0131 \u00f6l\u00e7\u00fcmleyerek tahmin edebiliyorlar, fakat ikisini birden \u00f6l\u00e7meleri her zaman m\u00fcmk\u00fcn de\u011fil.<\/p>\n<p>Ohio Eyalet \u00dcniversitesi\u2019nden mineral fizik\u00e7isi Wendy Panero, gezegenle ilgili kestirimlerin kesinlikten uzak oldu\u011funu s\u00f6yl\u00fcyor. Biliminsanlar\u0131 gezegenin \u00e7ekirde\u011findeki kayan\u0131n, gaz temelli gezegenlerin atmosferinin derinliklerinde bulunan y\u00fcksek s\u0131cakl\u0131k ve bas\u0131n\u00e7 ko\u015fullar\u0131nda nas\u0131l davranabilece\u011fine dair fazla bilgiye sahip de\u011fil. Ara y\u00fczey eriyik lav veya atmosferin nerede bitip de kayan\u0131n ba\u015flad\u0131\u011f\u0131n\u0131n net olmad\u0131\u011f\u0131 ge\u00e7i\u015fken bir s\u0131n\u0131r olabilir. Panero, \u201cBu ara y\u00fczeyin neye benzedi\u011fini s\u00f6yleyen malzeme \u00f6zelliklerine dair yeterince bilgi sahibi de\u011filiz\u201d diyor.<\/p>\n<p>Ayr\u0131ca gezegenin yo\u011funlu\u011funu bilmek D\u00fcnya benzeri bir y\u00fczeye sahip olup olmad\u0131\u011f\u0131n\u0131 s\u00f6ylemek i\u00e7in yeterli de\u011fildir. Her \u015feyden \u00f6nce, Ven\u00fcs yakla\u015f\u0131k olarak D\u00fcnya ile ayn\u0131 boyut ve k\u00fctlede ve G\u00fcne\u015f\u2019e ya\u015fama elveri\u015fli b\u00f6lgenin s\u0131n\u0131r\u0131ndan az bir miktar daha yak\u0131nda yer al\u0131yor. Fakat Ven\u00fcs\u2019\u00fcn atmosfer kimyas\u0131 y\u00fczeyini kur\u015funun eriyece\u011fi s\u0131cakl\u0131klarda kavuruyor. Kaliforniya \u00dcniversitesi\u2019nde gezegenler \u00fczerine \u00e7al\u0131\u015fan astrofizik\u00e7i Stephen Kane, \u201cVen\u00fcs, boyutun her \u015fey olmad\u0131\u011f\u0131 konusunda bizleri uyar\u0131yor\u201d diyor ve ekliyor, \u201cBu gezegen, ya\u015fama elveri\u015flili\u011fin karma\u015f\u0131kl\u0131\u011f\u0131n\u0131 bize hayk\u0131r\u0131yor\u201d.<\/p>\n<p><strong>B\u00f6lgenin d\u0131\u015f\u0131na bakmak<\/strong><br \/>\nJeofizik laboratuvarlar\u0131nda farkl\u0131 mirerallerin y\u00fcksek bas\u0131n\u00e7 ve s\u0131cakl\u0131k alt\u0131nda nas\u0131l davrand\u0131\u011f\u0131n\u0131n test edildi\u011fi deneyler, hangi d\u00fcnyalar\u0131n ya\u015fama elveri\u015fli oldu\u011fu konusuna netlik kazand\u0131rabilir. Arizona Eyalet \u00dcniversitesi\u2019nden Cayman Unterborn, mineraller \u00fczerinde yap\u0131lan bu t\u00fcr ara\u015ft\u0131rmalar ve farkl\u0131 tip gezegenlerin nas\u0131l olu\u015ftu\u011funa dair kuramlar sayesinde, K2 18b\u2019nin D\u00fcnya\u2019ya m\u0131, yoksa Ven\u00fcs\u2019e mi daha \u00e7ok benzedi\u011fini bilme imkan\u0131m\u0131z olabilece\u011fini s\u00f6yl\u00fcyor.<\/p>\n<p>Dahas\u0131, ya\u015fama elveri\u015fli d\u00fcnyalardan baz\u0131lar\u0131 ya\u015fama elveri\u015fli b\u00f6lgenin d\u0131\u015f\u0131nda dahi olabilir. Etan ve metandan olu\u015fan g\u00f6lleri ve nehirleriyle Sat\u00fcrn\u2019\u00fcn uydusu Titan, astrobiyologlar i\u00e7in G\u00fcne\u015f Sistemi\u2019nin en \u00e7ekici hedeflerinden biri. Sat\u00fcrn ve J\u00fcpiter\u2019in di\u011fer buzlu uydular\u0131 donmu\u015f kabuklar\u0131n\u0131n alt\u0131nda, zaman zaman suyun s\u0131v\u0131 formda bulunmas\u0131na imkan tan\u0131yan ko\u015fullara sahip biyosferler bar\u0131nd\u0131r\u0131yor olabilir. Bunlar\u0131n hi\u00e7biri G\u00fcne\u015f\u2019in ya\u015fama elveri\u015fli b\u00f6lgesinde de\u011fil. North Carolina Eyalet \u00dcniversitesi\u2019nde gezegen jeolojisi \u00fczerine \u00e7al\u0131\u015fan Paul Byrne, \u201cYa\u015fanabilir b\u00f6lge ya\u015fam\u0131n bulunabilece\u011fi ayr\u0131cal\u0131kl\u0131 bir b\u00f6lge de\u011fil\u201d diyor.<\/p>\n<figure id=\"attachment_37663\" aria-describedby=\"caption-attachment-37663\" style=\"width: 300px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-37663 size-medium\" src=\"https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim-300x199.jpg\" alt=\"\" width=\"300\" height=\"199\" srcset=\"https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim-300x199.jpg 300w, https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim-600x397.jpg 600w, https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/10\/resim.jpg 680w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><figcaption id=\"caption-attachment-37663\" class=\"wp-caption-text\">\u00d6tegezegen ke\u015fif program\u0131<\/figcaption><\/figure>\n<p><strong>Tam olarak do\u011fru<\/strong><br \/>\nYandaki resimde k\u0131rm\u0131z\u0131 c\u00fcce y\u0131ld\u0131z K2 18\u2019in gezegen sisteminde ye\u015fil renkle g\u00f6sterilmi\u015f olan ya\u015fama elveri\u015fli b\u00f6lge, s\u0131cakl\u0131\u011f\u0131n suyun s\u0131v\u0131 formda bulunabilmesi i\u00e7in tam olarak do\u011fru de\u011ferlerde oldu\u011funun d\u00fc\u015f\u00fcn\u00fcld\u00fc\u011f\u00fc b\u00f6lgeyi belirtiyor. Ancak bu b\u00f6lgede bulunmak bir gezegenin ya\u015fama elveri\u015fli oldu\u011fu anlam\u0131na gelmez, keza bu b\u00f6lgenin d\u0131\u015f\u0131nda yer almak da gezegendeki ya\u015fam olas\u0131l\u0131\u011f\u0131n\u0131 ortadan kald\u0131rmaz.<\/p>\n<p>Astronomlar, ya\u015fama elveri\u015fli b\u00f6lgenin noksanl\u0131klar\u0131ndan y\u0131lm\u0131\u015f vaziyette, alternatif isimler \u00f6nerdiler; s\u0131cakl\u0131k b\u00f6lgesi, s\u0131v\u0131 su b\u00f6lgesi, avlanma b\u00f6lgesi (astronomlar\u0131n ya\u015fam\u0131n izlerini avlad\u0131klar\u0131 esas yer olmas\u0131ndan dolay\u0131) ve ekosfer bunlardan birka\u00e7\u0131d\u0131r. Kreidberg, daha az mu\u011flak bir se\u00e7enek olarak son zamanlarda modas\u0131 ge\u00e7mi\u015f olan \u201cGoldilocks B\u00f6lgesi\u201dni diriltmeyi \u00f6neriyor. Christiansen ise \u015faka yollu olarak \u201cEarth Could Have Liquid Water On The Surface\u201d (Y\u00fczeyinde S\u0131v\u0131 Su Bulunabilecek D\u00fcnya\u201d) ifadesinin k\u0131saltmas\u0131 olarak &#8220;ECHaLWOTS B\u00f6lgesi&#8221; ismini \u00f6neriyor.<\/p>\n<p>\u201cNeden tutulacak bir alternatif bulmakta g\u00fc\u00e7l\u00fck ya\u015fad\u0131\u011f\u0131m\u0131z\u0131 hemen g\u00f6rebilirsiniz\u201d diyor Tasker. Bu t\u00fcr terimler orjinal terimin sahip oldu\u011fu problemlerin baz\u0131lar\u0131n\u0131 ta\u015f\u0131yor; bir yandan bu b\u00f6lgede yer alan t\u00fcm gezegenler \u0131l\u0131man veya nemli olmayacak, \u00f6te yandan di\u011fer adaylar yeni tan\u0131m\u0131 kar\u015f\u0131lamad\u0131\u011f\u0131 i\u00e7in elenecek. Bu y\u00fczden baz\u0131 astrobiyologlar, daha fazla veri ve karakteristik niteli\u011fi hesaba katmay\u0131 sa\u011flayacak bir t\u00fcr ya\u015fama elveri\u015flilik indeksi olu\u015fturmaya \u00e7al\u0131\u015f\u0131yorlar. Porto Riko \u00dcniversitesi\u2019nden Abel M\u00e9ndez bunun g\u00fcncel \u00f6rneklerinden birini geli\u015ftirirken ekolojiden ilham alm\u0131\u015f. M\u00e9ndez, \u201cAstrobiyologlar ya\u015fama elveri\u015flili\u011fin \u00f6l\u00e7\u00fclmesinin \u00e7ok zor oldu\u011funu d\u00fc\u015f\u00fcn\u00fcyorlar\u201d diyor. Ancak 70\u2019li y\u0131llarda, ABD Bal\u0131k ve Vah\u015fi Ya\u015fam Servisi kara ve sudaki insan faaliyetlerinin yak\u0131nlardaki bitki ve hayvanlar \u00fczerinde nas\u0131l bir etkisi olaca\u011f\u0131n\u0131 \u00f6l\u00e7menin bir yoluyla \u00e7\u0131kageldi\u011finde, ekolojistlerin de benzer bir probleme sahip oldu\u011funu s\u00f6yl\u00fcyor. Ajans\u0131n Habitat Uygunluk \u0130ndeksi, belirli bir \u00e7evredeki mevcut enerji miktar\u0131n\u0131 hesaba katarak o \u00e7evrenin ne kadarl\u0131k biyok\u00fctleyi idame ettirebilece\u011fine dair bir \u00f6l\u00e7\u00fct sunuyor.<\/p>\n<p>M\u00e9ndez ve meslekta\u015flar\u0131 bu indeksi yeniden d\u00fczenleyerek 2018\u2019de Teksas\u2019da ger\u00e7ekle\u015ftirilen Ay ve Gezegen Bilimi Konferans\u0131\u2019nda sundular. Ara\u015ft\u0131rmac\u0131lar\u0131n elde etti\u011fi denklem gezegenin ya\u015fama elveri\u015flili\u011fini tartan be\u015f de\u011fi\u015fken i\u00e7eriyor; gezegenin ald\u0131\u011f\u0131 \u0131\u015f\u0131k miktar\u0131, yar\u0131\u00e7ap\u0131, y\u00fczeyinin yans\u0131t\u0131c\u0131l\u0131\u011f\u0131, y\u00fczeyin okyanusla \u00f6rt\u00fcl\u00fc b\u00f6l\u00fcm\u00fcn\u00fcn oran\u0131 ve atmosfer yo\u011funlu\u011fu. Tabii bu de\u011fi\u015fkenlerden son \u00fc\u00e7\u00fcn\u00fc tespit etmek \u015fuanki teleskoplar\u0131m\u0131z\u0131n ula\u015fabilece\u011finin \u00f6tesinde kal\u0131yor. M\u00e9ndez, olu\u015fturduklar\u0131 bu \u00e7er\u00e7evenin ara\u015ft\u0131rmac\u0131lara tam olarak neyin \u00f6l\u00e7\u00fclmesi gerekti\u011fini s\u00f6yledi\u011fini ve bu \u00f6l\u00e7\u00fcmler i\u00e7in gerekli teknolojinin 10 ila 20 y\u0131l \u00f6temizde oldu\u011funu d\u00fc\u015f\u00fcnd\u00fc\u011f\u00fcn\u00fc ifade ediyor.<\/p>\n<p>Baz\u0131 astronomlar ise bir gezegende ya\u015fama elveri\u015flili\u011fini etkileyebilecek di\u011fer fakt\u00f6rler (Aktif jeolojik d\u00f6ng\u00fc, erimi\u015f bir \u00e7ekirdek, plaka tektoni\u011fi, atmosfere gaz sal\u0131n\u0131m\u0131 yapan yanarda\u011flar ve gezegeni y\u0131ld\u0131z f\u0131rt\u0131nalar\u0131na kar\u015f\u0131 koruyan bir manyetik alan\u0131n olup olmamas\u0131 gibi) d\u00fc\u015f\u00fcn\u00fcld\u00fc\u011f\u00fcnde, bu t\u00fcr bir indeksin kullan\u0131\u015fl\u0131l\u0131\u011f\u0131n\u0131 ku\u015fkulu buluyor. \u00d6rnek olarak verilen bu fakt\u00f6rler de bug\u00fcn\u00fcn teknolojisiyle D\u00fcnya\u2019dan tespit edilemiyor; baz\u0131lar\u0131 belki de hi\u00e7 edilemeyecek. Harvard\u2019l\u0131 astronom Charbonneau, bu fakt\u00f6rlerle ilgili uzun bir liste yap\u0131labilece\u011fini s\u00f6yl\u00fcyor.<\/p>\n<p><strong>Ya\u015fama elveri\u015flili\u011fi unut, sadece ya\u015fam\u0131 ara<br \/>\n<\/strong>\u201cE\u011fer \u00e7antan\u0131z\u0131 toplay\u0131p oraya gidebilece\u011finizden emin olmak istiyorsan\u0131z, bir biyo-imzaya ihtiyac\u0131n\u0131z var.\u201d diyor Kane. Burada &#8220;biyo-imza&#8221; ile kastedilen, ya\u015fam\u0131n gezegenin atmosfer kimyas\u0131nda yaratt\u0131\u011f\u0131 de\u011fi\u015fikliklere dair bir i\u015farettir. &#8220;E\u011fer a\u00e7\u0131k biyo-imzalar tespit edersek bu, tan\u0131m gere\u011fi o gezegenin ya\u015fama elveri\u015fli oldu\u011fu anlam\u0131na gelir, \u00e7\u00fcnk\u00fc orada ya\u015fayan bir \u015feyler vard\u0131r\u201d.<\/p>\n<p>NASA halihaz\u0131rda D\u00fcnya benzeri \u00f6tegezegenlerin g\u00f6ky\u00fcz\u00fcn\u00fc tarayabilme kabiliyetine sahip 2 teleskobun planlar\u0131n\u0131 de\u011ferlendiriyor. Bu teleskoplar do\u011frudan yasam\u0131n izlerini aramak a\u00e7\u0131s\u0131ndan ileriye do\u011fru bir at\u0131l\u0131m sa\u011flayabilir. &#8220;Ya\u015fama Elveri\u015fli \u00d6tegezegen G\u00f6zlemevi&#8221; veya \u0130ngilizce k\u0131saltmas\u0131yla HabEx (Habitable Exoplanet Observatory), G\u00fcne\u015f\u2019e benzeyen y\u0131ld\u0131zlar etraf\u0131nda d\u00f6nen D\u00fcnya benzeri bir d\u00fczine (veya daha fazla) gezegenin foto\u011fraflar\u0131n\u0131 \u00e7ekebilecek. Takma ad\u0131 LUVOIR olan &#8220;B\u00fcy\u00fck Mor \u00d6tesi\/Optik\/K\u0131z\u0131l \u00d6tesi Taray\u0131c\u0131&#8221; ise ayn\u0131 i\u015fi 100 gezegene kadar yapabilecek. \u0130ki teleskop da gezegenlerin atmosferlerindeki kimyasal ya\u015fam izlerini arayacak.<\/p>\n<p>Kasting, ya\u015fama elveri\u015fli b\u00f6lge kavram\u0131n\u0131n HabEx ve LUVOIR gibi projelerin tasarlanmas\u0131 i\u00e7in hala faydal\u0131 oldu\u011funu s\u00f6yl\u00fcyor. Bir y\u0131ld\u0131zdan belirli bir mesafe uzakl\u0131\u011fa odaklanmak, m\u00fchendislere ne b\u00fcy\u00fckl\u00fckte bir teleskop yapmalar\u0131 gerekti\u011fini s\u00f6yl\u00fcyor. \u0130ki teleskobun tasar\u0131m\u0131nda da Kasting\u2019in tan\u0131m\u0131n\u0131n 2013\u2019te, NASA Goddard F\u0131rlatma \u00dcss\u00fc\u2019nde astronom olan Ravi Kopparapu\u2019nun ba\u015f\u0131n\u0131 \u00e7ekti\u011fi ekibin \u00e7al\u0131\u015fmas\u0131yla g\u00fcncellenen versiyonundan faydalan\u0131lm\u0131\u015f.<\/p>\n<p>Kasting \u201cTutucu davran\u0131p, tan\u0131yabilece\u011fimiz bir \u015feyler g\u00f6rmek \u00fczere teleskoplar tasarlamaya \u00e7al\u0131\u015f\u0131yoruz\u201d diyor ve ekliyor: \u201cE\u011fer bize benzemiyorsa ya\u015fam\u0131 tan\u0131mak olduk\u00e7a zor\u201d. E\u011fer ya\u015fam\u0131n izleri sonunda bulunursa, \u201cya\u015fama elveri\u015fli b\u00f6lge\u201d terimi \u00fczerindeki tart\u0131\u015fmalar \u00f6ylece s\u00f6n\u00fcp gidebilir.<\/p>\n<p><strong>Kaynak:<\/strong> https:\/\/www.sciencenews.org\/article\/why-just-being-habitable-zone-doesnt-make-exoplanets-livable<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u201cEvrende yaln\u0131z m\u0131y\u0131z?\u201d sorusundan daha merak uyand\u0131r\u0131c\u0131 pek az soru vard\u0131r. Uzayda ya\u015fama dair aray\u0131\u015f insano\u011flunun hayal g\u00fcc\u00fcn\u00fc bin y\u0131llard\u0131r me\u015fgul etmekte. Bug\u00fcn, G\u00fcne\u015f haricinde bir y\u0131ld\u0131z\u0131n etraf\u0131nda hareket eden ilk gezegenin ke\u015ffinden bu yana ge\u00e7en 25 y\u0131l\u0131n ard\u0131ndan, bu sorunun cevab\u0131n\u0131 bulmaya hi\u00e7 olmad\u0131\u011f\u0131 kadar yak\u0131n\u0131z. Harvard \u00dcniversitesi\u2019nden astronom David Charbonneau, \u201cHemen hemen herkes [&hellip;]<\/p>\n","protected":false},"author":677,"featured_media":37665,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19],"tags":[1062,3282,392,595],"class_list":["post-37662","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bilim-gundemi","tag-gozlemevi","tag-otegezegen","tag-uzay","tag-yasam"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts\/37662","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\/677"}],"replies":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/comments?post=37662"}],"version-history":[{"count":0,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts\/37662\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/media\/37665"}],"wp:attachment":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/media?parent=37662"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/categories?post=37662"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/tags?post=37662"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}