Bir y\u0131ld\u0131z\u0131n etraf\u0131nda dolanan ve kendisi y\u0131ld\u0131z olmayan do\u011fal g\u00f6k cisimlerine gezegen ad\u0131 verilir. Dar anlam\u0131yla, G\u00fcne\u015f Sistemi i\u00e7inde, G\u00fcne\u015f’in do\u011frudan uydusu olan ve Uluslararas\u0131 G\u00f6kbilim Birli\u011fi (IAU) taraf\u0131ndan bu tan\u0131ma uygun bulunmu\u015f 8 g\u00f6k cismini belirlemede kullan\u0131l\u0131r. G\u00fcne\u015f Sistemi’nde, resmi olarak kabul edilen ‘sekiz gezegen’den ba\u015fka, bu cisimlerle boyut, y\u00f6r\u00fcnge ve fiziksel \u00f6zellikler a\u00e7\u0131s\u0131ndan ayn\u0131 gruba konabilecek yeni g\u00f6k cisimlerinin ke\u015ffedilmesi, bir yandan da ba\u015fka y\u0131ld\u0131zlar\u0131n etraf\u0131nda da G\u00fcne\u015f Sistemi gezegenlerine benzer g\u00f6k cisimlerinin doland\u0131\u011f\u0131n\u0131n saptanmas\u0131, ‘gezegen’ tan\u0131m\u0131n\u0131n s\u0131n\u0131rlar\u0131n\u0131n bulan\u0131kla\u015fmas\u0131na neden olmu\u015ftur.
\nUluslararas\u0131 G\u00f6kbilim Birli\u011fi’nin (IAU), 1919 y\u0131l\u0131ndan bu yana kabul etti\u011fi G\u00fcne\u015f Sistemi’nin 8 gezegeni, g\u00fcne\u015fe yak\u0131nl\u0131k s\u0131ralar\u0131na g\u00f6re \u015funlard\u0131r:
\n1. Merk\u00fcr , 2. Ven\u00fcs , 3. D\u00fcnya , 4. Mars , 5. J\u00fcpiter , 6. Sat\u00fcrn , 7. Uran\u00fcs , 8. Nept\u00fcn Bu 8 gezegenin d\u0131\u015f\u0131nda daha \u00f6nce gezegen olarak tan\u0131mlanan Pl\u00fcton IAU’nun yeni tan\u0131mlamas\u0131na g\u00f6re C\u00fcce Gezegen olarak kabul edilmektedir.
\nG\u00fcne\u015f Sistemi d\u0131\u015f\u0131ndaki gezegenler
\n1995 y\u0131l\u0131nda Michel Mayor ve Didier Queloz taraf\u0131ndan 51 Pegasi adl\u0131 y\u0131ld\u0131z\u0131n \u00e7evresinde d\u00f6nen bir g\u00f6k cismi ke\u015ffedildi\u011finde, bu cismin ‘gezegen’ olarak tan\u0131mlanmas\u0131 uygun g\u00f6r\u00fcld\u00fc. 1995-2005 y\u0131llar\u0131 aras\u0131nda yap\u0131lan g\u00f6zlemlerle, 100’\u00fc a\u015fk\u0131n de\u011fi\u015fik y\u0131ld\u0131z \u00e7evresinde dolanan 150’den fazla gezegen bulundu. G\u00fcne\u015f Sistemi gezegenleri ile kar\u0131\u015ft\u0131r\u0131lmamas\u0131 i\u00e7in bu cisimlere ‘G\u00fcne\u015f d\u0131\u015f\u0131 gezegenler’ veya G\u00fcne\u015f Sistemi d\u0131\u015f\u0131 gezegenler ad\u0131 verilmektedir. Yine kar\u0131\u015f\u0131kl\u0131\u011f\u0131 \u00f6nlemek amac\u0131yla, bu t\u00fcr gezegenlerin y\u0131ld\u0131zlar\u0131 ile birlikte olu\u015fturduklar\u0131 sistemlere genel olarak gezegen sistemi ya da ‘y\u0131ld\u0131z sistemi’ ad\u0131 verilmektedir. ‘G\u00fcne\u015f Sistemi’ ad\u0131 ise, yaln\u0131zca \u00f6zel ad olarak G\u00fcne\u015f ve uydular\u0131n\u0131n olu\u015fturdu\u011fu gezegen sistemini tan\u0131mlamada kullan\u0131l\u0131r. ek olarak 1996 y\u0131l\u0131nda amerikal\u0131 uzay bilimcisi Arthur Frank Elbourn ‘un yapm\u0131\u015f oldu\u011fu bir tak\u0131m ara\u015ft\u0131rmalar uzay hakk\u0131nda daha da fazla bilgi almam\u0131z\u0131 sa\u011flam\u0131\u015ft\u0131r. Arthur Frank Elbourn un yapm\u0131\u015f oldu\u011fu \u00e7al\u0131\u015fmalarda 10 olan gezegen say\u0131s\u0131 asl\u0131nda 12 gezegene vardi. goono ve Elbourn ismi verdi\u011fi iki gezegen daha ke\u015ffetti. Nasa taraf\u0131ndan do\u011frulanan bu gezegenler fazla medyaya duyurulmad\u0131.
\nTarih boyunca gezegen kavram\u0131
\nElimize ula\u015fan tarihsel kay\u0131tlar incelendi\u011finde, T\u00fcrk\u00e7e’nin gen\u00e7 s\u00f6zc\u00fcklerinden olan ‘gezegen’in di\u011fer dillerde uzun s\u00fcredir var olan kar\u015f\u0131l\u0131klar\u0131n\u0131n, g\u00f6ky\u00fcz\u00fcnde y\u0131ld\u0131zlar\u0131n al\u0131\u015f\u0131lm\u0131\u015f hareketlerinden farkl\u0131 davran\u0131\u015flar\u0131 ile dikkati \u00e7eken ‘ayk\u0131r\u0131’ y\u0131ld\u0131zlar i\u00e7in kullan\u0131ld\u0131\u011f\u0131 g\u00f6r\u00fcl\u00fcr. Bat\u0131 dillerinde gezegen kavram\u0131 Eski Yunan’da ‘ba\u015f\u0131bo\u015f dola\u015fan’ anlam\u0131nda kullan\u0131lan planitis (\u03c0\u03bb\u03b1\u03bd\u03ae\u03c4\u03b7\u03c2) s\u00f6zc\u00fc\u011f\u00fcnden t\u00fcretilmi\u015f s\u00f6zc\u00fcklerle ifade edilmektedir. Yak\u0131n tarihe kadar T\u00fcrk\u00e7e’de kullan\u0131lan Arap\u00e7a k\u00f6kenli seyyare s\u00f6zc\u00fc\u011f\u00fc de benzer anlam ta\u015f\u0131maktad\u0131r. T\u00fcrk\u00e7e gezegen s\u00f6zc\u00fc\u011f\u00fc de, bu y\u0131ld\u0131zlar\u0131n g\u00f6ky\u00fcz\u00fcnde di\u011fer sabit y\u0131ld\u0131zlar\u0131n aras\u0131nda ‘gezinmelerinden’ esinlenilerek t\u00fcretilmi\u015ftir.
\n17.ci y\u00fczy\u0131la dek bilinen be\u015f gezegen (Merk\u00fcr, Ven\u00fcs, Mars, J\u00fcpiter ve Sat\u00fcrn), insan k\u00fclt\u00fcr\u00fc ile tarih boyunca i\u00e7i\u00e7e olmu\u015f, \u00e7e\u015fitli k\u00fclt\u00fcrlerde tanr\u0131larla ba\u011fda\u015ft\u0131r\u0131larak mitolojinin, klasik elementlerle ba\u011fda\u015ft\u0131r\u0131larak felsefenin ve astrolojinin \u00f6nemli bir par\u00e7as\u0131n\u0131 olu\u015fturmu\u015flard\u0131r. 17.ci y\u00fczy\u0131lda Kopernik’in o g\u00fcne dek yayg\u0131n olan yermerkezli g\u00f6r\u00fc\u015f\u00fc sarsan kozmolojik devrimi ile g\u00fcne\u015fmerkezli evren anlay\u0131\u015f\u0131n\u0131n a\u011f\u0131rl\u0131k kazanmas\u0131 sonucunda d\u00fcnyan\u0131n da bir gezegen oldu\u011fu kabul edilmi\u015f, b\u00f6ylece gezegen kavram\u0131 ‘g\u00f6kte ba\u015f\u0131bo\u015f dola\u015fan y\u0131ld\u0131z’dan g\u00fcn\u00fcm\u00fczdeki g\u00f6kbilimsel anlam\u0131na oturmu\u015ftur.
\n18.ci y\u00fczy\u0131lda ke\u015ffedilen Uran\u00fcs gezegenler listesine yedinci s\u0131rayla kolayl\u0131kla eklenirken, 1801 ve 1802’de G\u00fcne\u015f Sistemi’nin Ceres ve Pallas adlar\u0131n\u0131 alan iki yeni \u00fcyesi bulundu\u011funda, k\u00fc\u00e7\u00fckl\u00fckleri nedeniyle gezegen say\u0131lmayarak Sir William Herschel’in verdi\u011fi asteroit tan\u0131m\u0131 i\u00e7ine al\u0131nd\u0131lar. \u0130zleyen y\u0131llarda ke\u015ffedilen benzer niteliklerde yeni k\u00fc\u00e7\u00fck g\u00f6k cisimleri de bu kategoriye eklendiler. B\u00f6ylece Titius-Bode yasas\u0131n\u0131n \u00f6ng\u00f6rd\u00fc\u011f\u00fc \u015fekilde Mars ile J\u00fcpiter y\u00f6r\u00fcngeleri aras\u0131nda bir ba\u015fka gezegen bulunmas\u0131 gerekti\u011fi sorunu \u00e7\u00f6z\u00fcmlenmi\u015f oldu. Ancak bu kez Uran\u00fcs y\u00f6r\u00fcngesindeki tedirginliklerden sorumlu yeni bir gezegen aray\u0131\u015f\u0131 ba\u015flad\u0131. Bu sorunun yan\u0131t\u0131n\u0131 da 1846 y\u0131l\u0131nda bulunan ve sekizinci gezegen olarak benimsenen Nept\u00fcn getirdi. G\u00fcne\u015f Sistemi i\u00e7inde g\u00f6zlenen t\u00fcm tedirginliklerin hen\u00fcz ke\u015ffedilmemi\u015f bir ‘bilinmeyen gezegen’ ile a\u00e7\u0131klanabilece\u011fi yakla\u015f\u0131m\u0131n\u0131n bu \u015fekilde meyvas\u0131n\u0131 vermesi, ‘gezegen avc\u0131lar\u0131n\u0131’ cesaretlendirerek dokuzuncu gezegenin aranmas\u0131na ba\u015fland\u0131. Ancak, giderek daha g\u00fc\u00e7l\u00fc teleskoplar\u0131n yap\u0131lmas\u0131, g\u00f6ky\u00fcz\u00fcn\u00fc inceleyen insan ve kurulu\u015f say\u0131s\u0131n\u0131n artmas\u0131, 19.y\u00fczy\u0131l sonunda astrofotografi tekni\u011finin ortaya \u00e7\u0131kmas\u0131 gibi geli\u015fmeler sayesinde \u00f6nemsiz say\u0131lacak g\u00f6kcisimlerinin saptanabilir hale gelmesine ve yeni bulunan asteroit say\u0131s\u0131n\u0131n bini a\u015fmas\u0131na kar\u015f\u0131n, 1930’da Pl\u00fcton bulundu\u011funda neredeyse y\u00fcz y\u0131l ge\u00e7mi\u015fti. Bu uzun bekleyi\u015f, Pl\u00fcton’a dokuzuncu gezegen olma onurunu kazand\u0131r\u0131rken, a\u00e7\u0131klamas\u0131n\u0131 da birlikte getiriyordu: yeni gezegen o ana dek bilinen en k\u00fc\u00e7\u00fck gezegen Merk\u00fcr’\u00fcn yar\u0131s\u0131ndan daha k\u00fc\u00e7\u00fck \u00e7apta ve otuzda biri k\u00fctlesinde, aralar\u0131nda Ay’\u0131n da bulundu\u011fu bir\u00e7ok gezegen uydusundan daha k\u00fc\u00e7\u00fck, \u00fcstelik al\u0131\u015f\u0131lmad\u0131k bir y\u00f6r\u00fcngede idi. B\u00fct\u00fcn bunlara kar\u015f\u0131n, en b\u00fcy\u00fck asteroit Ceres’ten daha b\u00fcy\u00fck olan ve G\u00fcne\u015f \u00e7evresinde d\u00f6nen dokuzuncu b\u00fcy\u00fck g\u00f6k cismi olan Pl\u00fcton’un dokuzuncu gezegen s\u0131fat\u0131 20. y\u00fczy\u0131l sonlar\u0131na kadar tart\u0131\u015fma konusu olmad\u0131.
\nHollandal\u0131 g\u00f6kbilimci Kuiper taraf\u0131ndan kuramsal olarak ortaya at\u0131lan ve bug\u00fcn Kuiper ku\u015fa\u011f\u0131 olarak bilinen b\u00f6lge, G\u00fcne\u015f’ten 30-50 A.\u00dc (astronomi \u00fcnitesi-g\u00f6kbilim birimi) yani yakla\u015f\u0131k 4,5-7,5 milyar km. uzakl\u0131ktaki alan\u0131 kaplar ve G\u00fcne\u015f \u00e7evresinde d\u00f6nen \u00e7ok say\u0131da k\u00fc\u00e7\u00fck g\u00f6k cisminin bu aral\u0131kta yer ald\u0131klar\u0131na 1950’lerden bu yana inan\u0131lmaktad\u0131r. 1992 y\u0131l\u0131nda, o ana dek Kuiper ku\u015fa\u011f\u0131n\u0131n bilinen tek \u00fcyesi Pl\u00fcton gezegeni iken, (15760) 1992 QB1 ge\u00e7ici ad\u0131yla tan\u0131nan ‘ilk Kuiper ku\u015fa\u011f\u0131 cismi’nin bulunmas\u0131 ve bunu k\u0131sa s\u00fcrede \u00e7ok say\u0131da yenilerinin izlemesi ile bu yeni g\u00f6k cisimi s\u0131n\u0131f\u0131 bir kavram olarak netle\u015fmeye ba\u015flad\u0131. Pl\u00fcton’un bilimsel anlamda bu s\u0131n\u0131f\u0131n bir \u00fcyesi oldu\u011fu g\u00f6kbilim \u00e7evreleri taraf\u0131ndan kabul edilirken, hala bir gezegen olarak kabul edilip edilmeyece\u011fi konusu pop\u00fcler bir tart\u0131\u015fma bi\u00e7imini ald\u0131. Uluslararas\u0131 G\u00f6kbilim Birli\u011fi (IAU) 1999 y\u0131l\u0131nda Pl\u00fcton’un resmi olarak G\u00fcne\u015f sistemi’nin dokuzuncu gezegeni kabul edildi\u011fini ve bunun de\u011fi\u015ftirilmesinin d\u00fc\u015f\u00fcn\u00fclmedi\u011fini a\u00e7\u0131klayan bir bildiri yay\u0131nlamak zorunda kald\u0131.
\n2002 y\u0131l\u0131nda Pl\u00fcton’un yar\u0131s\u0131 \u00e7ap\u0131ndaki 50000 Quaoar’\u0131n, 2004’te ise neredeyse Pl\u00fcton b\u00fcy\u00fckl\u00fc\u011f\u00fcnde 90377 Sedna’n\u0131n ke\u015ffi, Pl\u00fcton’un di\u011fer Kuiper ku\u015fa\u011f\u0131 cisimlerinden (Kuiper Belt Objects-KBO) fazla ayr\u0131cal\u0131kl\u0131 olmad\u0131\u011f\u0131n\u0131 g\u00f6stermesi bak\u0131m\u0131ndan \u00f6nemli g\u00f6r\u00fcld\u00fc. 29 Temmuz 2005’de \u00fc\u00e7 yeni Kuiper ku\u015fa\u011f\u0131 cisimi daha bulundu\u011fu a\u00e7\u0131kland\u0131. Bunlardan 2003 UB313 adl\u0131 olan\u0131, Pl\u00fcton’dan daha b\u00fcy\u00fck olmas\u0131 nedeni ile baz\u0131lar\u0131nca 10.cu gezegen ilan edilirken bir yandan da Pl\u00fcton’un gezegen s\u0131fat\u0131n\u0131n g\u00f6zden ge\u00e7irilmesi tart\u0131\u015fmalar\u0131 yeniden alevlendi. amerika da yap\u0131lan ara\u015ft\u0131rmalar sonucunda asl\u0131nda 12 gezegen d\u0131\u015f\u0131nda d\u00f6rt gezegen daha ke\u015ffedilmi\u015f. bunlar pluton dan daha b\u00fcy\u00fck ve yap\u0131lan ara\u015ft\u0131rmalarda bu d\u00f6rt gezegenin bir tanesinde ya\u015famsal bir belirti olabilece\u011fi s\u00f6ylenmektedir. yaln\u0131z dunyaya \u00e7ok uzak olan bu d\u00f6rt gezegen nasa n\u0131n yapm\u0131\u015f oldu\u011fu gizlia ra\u015ft\u0131rmalar sonucunda ortaya \u00e7\u0131kar\u0131lm\u0131\u015f, ve medyadan bugune kadar saklanm\u0131\u015ft\u0131r. medyaya nas\u0131l s\u0131zd\u0131\u011f\u0131 bilinmemekte olup ara\u015ft\u0131rmalar\u0131n devam etti\u011fi s\u00f6ylenmektedir.<\/p>\n","protected":false},"excerpt":{"rendered":"
Bir y\u0131ld\u0131z\u0131n etraf\u0131nda dolanan ve kendisi y\u0131ld\u0131z olmayan do\u011fal g\u00f6k cisimlerine gezegen ad\u0131 verilir. Dar anlam\u0131yla, G\u00fcne\u015f Sistemi i\u00e7inde, G\u00fcne\u015f’in do\u011frudan uydusu olan ve Uluslararas\u0131 G\u00f6kbilim Birli\u011fi (IAU) taraf\u0131ndan bu tan\u0131ma uygun bulunmu\u015f 8 g\u00f6k cismini belirlemede kullan\u0131l\u0131r. G\u00fcne\u015f Sistemi’nde, resmi olarak kabul edilen ‘sekiz gezegen’den ba\u015fka, bu cisimlerle boyut, y\u00f6r\u00fcnge ve fiziksel \u00f6zellikler a\u00e7\u0131s\u0131ndan …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1407,1403],"tags":[3521,2830,2829,2859,2880,3524,3523,3525,2858,3522,2879],"class_list":["post-1205","post","type-post","status-publish","format-standard","hentry","category-fen-ve-teknoloji-odevleri","category-odevler","tag-gezegen-nedir","tag-jupiter","tag-mars","tag-merkur","tag-neptun","tag-saturn","tag-uluslararasi-gokbilim-birligi","tag-uranus","tag-venus","tag-yildiz-yildiz","tag-yorunge"],"_links":{"self":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts\/1205","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/comments?post=1205"}],"version-history":[{"count":0,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts\/1205\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/media?parent=1205"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/categories?post=1205"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/tags?post=1205"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}