Ukutyhubela imbali, izazinzulu ezininzi beziphakamisa iingcamango ezahlukahlukeneyo malunga nokusekwa kwezijikelezi-langa, indalo iphela kunye nesixokelelwano sezijikelezi-langa. Kule meko, siza kuthetha ngethiyori yanamhlanje ye iiplanethiimals. Olu luhlobo lwethiyori ebonisa ukuba iiplanethi zenziwe nge-nebula yegesi kunye nothuli lweenkwenkwezi.
Kweli nqaku siza kukuxelela malunga neempawu zenkcazo-bungcali yanamhlanje yeeplanethi, ezicebisile kunye nemiphumo eyaba nayo kwihlabathi le-astronomy kunye nesayensi.
Ithini ithiyori yeeplanetesimals?
Ithiyori yeeplanetesimals yi-hypothesis ezama ukucacisa indlela iiplanethi ezenziwe ngayo kwisixokelelwano sethu selanga kunye nezinye iinkqubo zeenkwenkwezi. Ngokwale thiyori, iiplanethi zivela kwilifu lerhasi nothuli ekuthiwa yiprotoplanetary nebula.
Okokuqala, ithiyori ichaza ukuba iprotoplanetary nebula sisiphumo selifu elikhulu lemolekyuli eliwa phantsi kwempembelelo yomxhuzulane. Njengoko i-contracts yelifu, iqala ukujikeleza ngokukhawuleza, ekhokelela ekwenziweni kwe-accretion disk ejikeleze inkwenkwezi encinci ebizwa ngokuba yi-progenitor star.
Ngaphakathi kule diski yokwandisa, amasuntswana amancinane othuli nomkhenkce, aziwa ngokuba ziiplanetesimals, ziqalisa ukungqubana zize ziqokelelane ngenxa yamandla omxhuzulane. Ezi planethi zisisiseko seeplanethi ezizayo. Njengoko ziqhubeka zikhula ukusuka kwiingquzulwano kunye nokudibanisa, iiplanetesimals ziba ziiprotoplanets, eziphuhlisa imizimba yeplanethi.
Enye yeempawu eziphambili zeeplanetesimals ubukhulu bazo. Ezi zinto zinokuqala ngobungakanani ukusuka kwiikhilomitha ezimbalwa ukuya kumakhulu eekhilomitha ububanzi. Ubunzima bayo kunye nokubunjwa kwayo kunokwahluka, kuxhomekeke kwindawo ngaphakathi kwidiski yokunyuka kunye nezinto ezikhoyo.
Ngapha koko, ithiyori yeeplanetesimals iyachaza Zenziwa njani iiplanethi ezinamatye kunye neeplanethi zegesi?. Izijikelezi-langa ezinamatye, njengoMhlaba noMars, zisondelelene nenkwenkwezi, apho amaqondo obushushu aphezulu kunye nezinto eziqinileyo. Izijikelezi-langa zegesi, njengeJupiter kunye neSaturn, zidala kwimimandla ethe qelele, apho amaqondo obushushu abandayo kwaye anerhasi kunye nezinto ezinomkhenkce zininzi.
Njengoko iiprotoplanets ziqhubeka zikhula, banokubamba izinto ezininzi kwaye ekugqibeleni babe ziiplanethi ezikhulileyo. Ithiyori yePlanetesimal inika ingcaciso ehambelanayo yendlela iiplanethi ezibufumana ngayo ubunzima bazo, i-orbit, kunye nokwakheka kwazo.
Ngubani ocebise le ngcamango?
Ithiyori yeeplanetesimals iye yaphuhliswa kwaye yatshintshwa zizazinzulu ezahlukeneyo kwimbali. Omnye wabokuqala abanegalelo elikhulu yaba sisazi ngeenkwenkwezi saseFransi kunye nengcali yezibalo uPierre-Simon Laplace. Wazalwa ngo-1749. ULaplace wayesaziwa ngomsebenzi wakhe kubuchwephesha basezulwini kunye nethiyori yomxhuzulane. Izifundo zakhe malunga nokusekwa kwenkqubo yelanga kunye nokuzinza kweeplanethi zabeka isiseko seengcamango zamva kwiiplanethi.
Esinye isazinzulu esibalulekileyo kule ngcamango yi-astronomer yaseSweden kunye ne-astrophysicist uVictor Safronov. Wazalelwa ngo-1917, uSafronov waqatshelwa ngomsebenzi wakhe onempembelelo ekubunjweni nasekuguqukeni kweenkqubo zeplanethi. Ucebise i-hypothesis yeplanethi kwaye wachaza ukubaluleka kwayo ekuyilweni kweeplanethi.
Kwakhona izazi ngeenkwenkwezi UGerald Kuiper kunye noGeorge Wetherill, yaba negalelo elikhulu kwingcamango yeeplanetisimals. UGerald Kuiper, owazalwa ngo-1905, wayesisazi ngeenkwenkwezi esaziwayo ngophando lwakhe malunga nommandla welanga kunye nokusekwa kweeplanethi. Umsebenzi wakhe waba negalelo ekuqondeni izinto zebhanti zeKuiper kunye nobudlelwane babo kwiiplanethi.
Kwelinye icala, uGeorge Wetherill wayesisazi ngeenkwenkwezi saseMelika owazalwa ngo-1925, kwaye wagqwesa kwinkalo yenzululwazi yeplanethi kunye nendalo yonke. Wenza uphando olusisiseko malunga nongquzulwano kunye nokuqokelelana kweeplanethisimals, kwaye waphuhlisa iimodeli zamanani ukulinganisa ukuvela kwazo kunye nokwakheka kweplanethi.
Ukubaluleka kwethiyori yeeplanetesimals kwi astronomy
Ithiyori yeeplanetesimals ibaluleke kakhulu kwinkalo yesayensi kunye nenzululwazi ngeenkwenkwezi ngenxa yeempembelelo zayo ezininzi kunye negalelo. Le ngcamango inike isiseko esiluqilima sokuqonda inkqubo yokwakheka kweplanethi kwisixokelelwano sethu selanga kwaye iye yabeka isiseko sokufunda ukubunjwa kweeplanethi kwezinye iinkqubo zeenkwenkwezi. Ezi zezona zizathu ziphambili zokubaluleka kwethiyori yeplanetesimal kwi astronomy:
- Imvelaphi yesixokelelwano selanga: Ithiyori yeeplanethi yenze ukuba kube lula ukuchaza indlela inkqubo yethu yelanga eyenziwe ngayo kwiprotoplanetary nebula. Kuyanceda ukuqonda ukuba iiplanethi, kuquka ezethu, zavela njani kumasuntswana amancinane kunye nendlela ezavela ngayo ekuhambeni kwexesha.
- Ukwenziwa kweeplanethi ze-extrasolar: Le ngcamango ayisebenzi kuphela kwisixokelelwano sethu selanga, kodwa ibe yinto ebalulekileyo ekufundeni nasekuqondeni ukubunjwa kweplanethi kwezinye iinkqubo zeenkwenkwezi. Ngokujonga kunye nokuhlalutya iidiski zeprotoplanetary ezijikeleze iinkwenkwezi ezincinci, izazi ngeenkwenkwezi ziye zafumana ubungqina bobukho beeplanetesimals kwaye ziye zakwazi ukuxela ukuba iiplanethi zenziwa njani kule mimandla.
- Ukuqulunqwa kunye neplanethi yendalo: Ithiyori yeeplanetesimals isinceda ukuba siqonde indlela ukubunjwa kunye nokwakheka kweeplanethi ezifunyanwa ngayo. Ukudibana kunye nokuqokelela kweeplanethi zeplanethi ngexesha lokubunjwa kweeplanethi zidlala indima ephambili ekunqumeni ukubunjwa kwangaphakathi nangaphandle kweeplanethi, kunye nokuguquguquka kwe-atmospheres kunye neendawo.
- Ukusasazwa kweeplanethi kunye neenkqubo zeplanethi: Le ngcamango ibe negalelo ekuqondweni kokusasazwa kunye nokwahluka kweenkqubo zeeplanethi kwindalo iphela. Isinceda siqonde ukuba kutheni ezinye iinkqubo zeenkwenkwezi zineeplanethi ezinamatye kufutshane nenkwenkwezi yazo, ngelixa ezinye zinezigebenga zegesi kude kuyo. Ukongezelela, inika ulwazi malunga nokubunjwa kweenyanga kunye nezinye izinto zasezulwini ezijikeleza iiplanethi.
Njengoko ubona, olu hlobo lwethiyori yenye yezona zinto zixhaswa kakhulu kwihlabathi lezesayensi kwaye sibulela kuyo sikuqonda ngcono ukubunjwa kweeplanethi. Ndiyathemba ukuba ngolu lwazi unokufunda ngakumbi malunga nethiyori yeeplanethi kunye nokubaluleka kwayo.