Indima Yamandla Adonsela Phansi Ekwakhekeni Kweplanethi
Amandla adonsela phansi “yisakhiwo” esiyinhloko esibumba uhlelo lwelanga namaplanethi alo. La mandla asebenza buthule kodwa ngokungaguquguquki, edonsa izinto kusukela esikalini sezinhlayiya zothuli kuya emadwaleni amakhulu ndawonye zibe amaplanethi azinzile azungeza izinkanyezi. Ngaphandle kwamandla adonsela phansi, igesi yendawo yonke kanye nothuli bekungeke kuhlangane kube izinto ezinkulu; bekuzohlala kuhlakazeke ngokungahleliwe kuyo yonke indawo. Ukuze siqonde ukuthi amaplanethi akheka kanjani, sidinga ukuhlola ukuthi amandla adonsela phansi asebenza kanjani kusukela ezigabeni zokuqala zokuzalwa kohlelo lwamaplanethi kuze kube sekuvuthweni kwalo.
1. Amafu ama-molecule kanye nokuqala kokuwa kwezinto
Ukwakheka kwamaplanethi kuqala kudala ngaphambi kokuba kube namaplanethi—ngisho nangaphambi kokuba kube nezinkanyezi. Isikhala esiphakathi kwezinkanyezi siqukethe amafu amangqamuzana, amaqoqo egesi (ikakhulukazi i-hydrogen ne-helium) kanye nothuli oluncane kakhulu. Lawa mafu abanda kakhulu futhi anciphile, kodwa angaba makhulu kakhulu. Ngesinye isikhathi, ifu lamangqamuzana lingaba elingazinzile. Izimbangela zokungazinzile zingahlukahluka: amaza okushaqeka avela ku-supernova eseduze, ukushayisana kwamafu, noma ukuphazamiseka kwamandla adonsela phansi okubangelwa ukudlula kwenye inkanyezi.
Uma ingxenye yefu iba nkulu ngokwanele, amandla adonsela phansi aqala "ukunqoba" ingcindezi yokushisa ezama ukusabalalisa izinto ngokwehlukana. Ukuwa kwamandla adonsela phansi kwenzeka: izinto zidonselwa enkabeni, zakha umongo onzima ngokwengeziwe. Lesi yisigaba sokuqala sokwakheka kwenkanyezi eyinhloko—inkanyezi yesikhathi esizayo—eyogcina isiba yinkaba yesimiso samaplanethi.
2. Amandla adonsela phansi kanye nokwakheka kwamadiski e-protoplanetary
Ukuwa akwenzeki ngqo enkabeni njengokuwa okulula kwamahhala. Amafu ama-molecule ngokuvamile anokujikeleza okuncane. Njengoba izinto ziwa, lokhu kujikeleza kuyashesha ngenxa yokulondolozwa komfutho we-angular (njengomuntu odlala i-figure skater edonsa izingalo zakhe ukuze asheshise ukujikeleza kwakhe). Ngenxa yalokho, izinto eziwayo azishayi ngokushesha enkabeni kodwa ziyasakazeka ukuze zakhe isakhiwo esiyisicaba, esijikelezayo: idiski ye-protoplanetary.
Yilapho amandla adonsela phansi edlala khona izindima ezimbili. Okokuqala, amandla adonsela phansi e-protostar abamba izinto ezikudiski ndawonye futhi azivimbele ukuba ziphume ziye esikhaleni esiphakathi kwezinkanyezi. Okwesibili, amandla adonsela phansi phakathi kwezinhlayiya ezingaphakathi kudiski asiza izinto ukuthi ziqale ukuhlangana ndawonye. I-protoplanetary disk "iyifektri" yamaplanethi, lapho igesi nothuli kuhlangana khona izigidi zeminyaka.
3. Kusukela othulini kuya kumaplanethi: amandla adonsela phansi njengeglue
Ezigabeni zokuqala zediski, izinhlayiya zothuli ziyashayisana futhi zinamathele ndawonye ngenxa yamandla kagesi kanye "nokunamathela" ezindaweni ezincane kakhulu. Kodwa-ke, ukuze kuthuthuke kusukela ezinhlayiyeni zothuli kuye ezintweni ezinkulu, amandla adonsela phansi agcina ethatha indawo. Lapho amaqoqo emakhulu ngokwanele (asukela kumamitha kuya kumakhilomitha), isisindo sawo sibanika amandla adonsela phansi abalulekile. Lezi zinto zibizwa ngokuthi ama-planesitemasimal.
Ukudonsa phansi kweplanethi kusebenza njengeglue ye-cosmic: kwandisa amathuba okushayisana “okunqwabelanayo” (ukwengeza ubukhulu) kunokuba kuqhume noma kubhujiswe. Ngaphezu kwalokho, kunomphumela obalulekile obizwa ngokuthi ukugxila okudonsela phansi: ukudonswa kwamandla adonsela phansi kwandisa “ingxenye ephumelelayo yento,” okwenza kube lula ukuthi kuthwetshulwe enye into edlula eduze.
4. Ukukhula kwe-Accretion: ukuzalwa kwe-embryo yeplanethi
Ngemva kokwakheka kwamaplanethi, inqubo yokukhula ingangena esigabeni sokukhula okubalekayo. Into enkulu kancane inomhubhe onamandla, okuvumela ukuthi ibambe izinto eziningi futhi ikhule ibe nkulu nakakhulu. Umehluko omncane ngobuningi ungakhula ngokushesha. Lokhu kuzala ama-embryo eplanethi, noma ama-protoplanethi, izinto ezinobukhulu beNyanga noma iMars eziqhubeka nokukhukhula izinto endleleni yazo.
Kodwa-ke, ukukhula akuqhubeki ngesivinini esikhulu. Njengoba ama-protoplanethi eqala ukubusa izifunda zawo ezizungezile, izinga lokushayisana liyanda futhi izinto ezitholakalayo ziyancipha. Lesi sigaba sishintshela ekukhuleni kwe-oligarchic: ama-protoplanethi amakhulu amaningana ("ama-oligarch") akhula ndawonye, ethonyana ngamandla adonsela phansi futhi elawula izindawo zawo.
5. Amandla adonsela phansi akha ukwakheka komjikelezo
Amaplanethi awagcini nje ngokuba mass, kodwa futhi amayelana nokuzungeza. Amandla adonsela phansi enkanyezi agcina amaplanethi ezungeza, kuyilapho ukusebenzisana kwamandla adonsela phansi phakathi kwama-protoplanets namanye amaplanethi kunquma ukuthi ama-orbit azinzile noma ayaphazamiseka.
Ngesikhathi sokwakheka, ama-protoplanethi avame ukuzwa ukudonswa kwegesi kanye ne-torque evela kudiski. Lokhu kungabangela ukufuduka, ukushintsha kwemizila yawo ngaphakathi noma ngaphandle. Ukufuduka kwenzeka ngenxa yokushintshana komfutho we-angular phakathi kweplanethi nediski yegesi, okuwumphumela wamandla adonsela phansi. Izinhlelo eziningi ze-exoplanetary ezitholakele zibonisa amaplanethi amakhulu aseduze kakhulu nezinkanyezi zawo (amaJupiter ashisayo), okusolwa kakhulu ukuthi akheke kakhulu ngaphandle bese ethuthela ngaphakathi.
Ngaphandle kokufuduka, amandla adonsela phansi angabamba amaplanethi nge-orbital resonances, okuyizindlela eziphindaphindwayo, njenge-2:1 noma i-3:2, lapho amaplanethi amabili "ebopha" ithonya lamandla adonsela phansi lomunye nomunye, eqinisa ukujikeleza kwawo ngesilinganiso esithile. Lawa ma-resonances abonakala ezinhlelweni eziningana zenyanga yeJupiter kanye nasezinhlelweni ezahlukene ze-exoplanetary.
6. Amandla adonsela phansi kanye nomehluko phakathi kwamaplanethi anamatshe kanye nama-giant gas
Kungani kukhona amaplanethi amancane, anamatshe (njengoMhlaba neMars) kanye nama-gas giants (njengoJupiter noSaturn)? Amandla adonsela phansi adlala indima, kanye nokushisa kanye nokusabalala kwezinto ezikudiski.
Kudiski yangaphakathi, eduze kwenkanyezi, amazinga okushisa aphezulu enza kube nzima ngama-transformer compounds (isb., amanzi, i-methane, i-ammonia) ukubanda. Kusele inani elincane kakhulu lezinto ezinamatshe nezensimbi ukwakha amaplanethi. Ngenxa yalokho, ama-protoplanets kulesi sifunda ngokuvamile awakhulu ngokwanele ukuheha nokugcina umoya ojiyile kakhulu wegesi.
Ngale kwalo mngcele kukhona "umugqa weqhwa," umngcele lapho amazinga okushisa aphansi khona ngokwanele ukuba kwakheke iqhwa. Iqhwa lengeza inani elikhulu lesisindo esiqinile esitholakalayo. Ingaphakathi leplanethi lingakhula ngokushesha, lifinyelele esisindweni esibucayi lapho amandla adonsela khona angadonsa khona inani elikhulu legesi ye-hydrogen ne-helium kusuka kudiski. Lesi yisihluthulelo sokuzalwa kwegesi enkulu: amandla adonsela phansi aqinile engaphakathi avumela ukwanda kwegesi ngokushesha ngaphambi kokuba igesi yediski iphele.
7. Ukushayisana okukhulu kanye nokuqedwa kokwakheka kwamaplanethi
Ezigabeni zokugcina, lapho igesi yediski incipha futhi iningi lesisindo esiqinile seliphenduke ama-protoplanethi, uhlelo alukakahlali "phansi." Amandla adonsela phansi phakathi kwama-protoplanethi angabangela ukuthi imijikelezo yawo ihlangane, okubangela ukushayisana okukhulu. Lokhu kushayisana kukholakala ukuthi kwenze izici eziningi ezibalulekile: isibonelo, inkolelo-mbono yomthelela omkhulu ichaza umsuka weNyanga, lapho into enobukhulu beMars (evame ukubizwa ngokuthi iTheia) ishayisana noMhlaba omncane, imfucumfucu yawo yakha idiski futhi ekugcineni yahlangana eNyangeni.
Ukushayisana okukhulu kungadala amaplanethi anezinsika ezihlukene, ukujikeleza okusheshayo, ukuthambekela okukhulu kwe-axial, noma ngisho nokukhumula i-mantle yeplanethi. Futhi, konke kuncike ekudonseleni phansi: amandla alawula indlela, isivinini sokushayisana, kanye nekhono lemfucumfucu lokuhlangana kabusha.
8. Amandla adonsela phansi ngemva kokwakheka kweplanethi: ukuhlanzwa nokuqina
Iplanethi “eyakhiwe” ayigcini nje ngokukhula; iphinda isuse umjikelezo wayo. Uma inobunzima obanele, iplanethi izosusa noma yiziphi izilwane ezisele zamaplanethi ngezindlela ezintathu: ukushayisana nazo, ukuzikhipha ohlelweni, noma ukushintsha umjikelezo wazo ukuze zingabe zisadlula. Lesi esinye sezizathu zokuthi incazelo yesimanje yeplanethi igcizelela ikhono “lokususa umakhelwane ozungezayo.”
Ngokuhamba kwesikhathi, ukuzinza kwesimiso samaplanethi kuhlala kunqunywa amandla adonsela phansi. Ukusebenzisana okuncane kunganqwabelana eminyakeni eyizigidi noma izigidigidi, ngezinye izikhathi kushintshe ukuguquguquka kwe-orbital kanye nokuthambekela, noma kubangele ukungazinzi okubangela ukuba amaplanethi akhishwe. Ezinhlelweni eziningi, ikakhulukazi lezo ezinamaplanethi asondelene kakhulu, ibhalansi ebucayi yamandla adonsela phansi inquma ukuthi uhlelo luyasinda noma luyawa.
Isiphetho
Amandla adonsela phansi angamandla ayinhloko aguqula izinto ezihlakazekile ze-cosmic zibe amaplanethi ahlelekile. Abangela ukuwohloka kwamafu ama-molecule, akha amadiski e-protoplanetary, avumela uthuli namatshe ukuthi kuhlangane kube amaplanethi, kusheshiswe ukwanda kube ama-protoplanets, kulawula ukufuduka kwe-orbital kanye nokuzwakala kwe-resonance, futhi kunqume ukuthi iplanethi ingaba yigesi enkulu noma ihlale inamadwala. Ngisho nangemva kokuba amaplanethi akheke, amandla adonsela phansi ayaqhubeka nokubumba ukuvela kwesistimu ngokushayisana, ukucaca kwe-orbital, kanye nokuguquguquka kwesikhathi eside.
Ngamanye amazwi, yonke iplanethi iwumkhiqizo wamandla adonsela phansi—amandla alula, ngokuhamba kwesikhathi kanye nokusebenzisana okuyinkimbinkimbi, adale ukuhlukahluka okukhulu kwemihlaba endaweni yonke.
