Ukuzinza Komjikelezo Weplanethi
Ukuzinza kwemijikelezo yamaplanethi kungenye yezihloko ezibaluleke kakhulu ku-astronomy kanye ne-astronomy dynamics. Uma sibheka uhlelo lwelanga, amaplanethi abonakala ehamba njalo ezungeze iLanga izigidigidi zeminyaka. Lokhu kuvumelana akulona iphutha, kodwa kunalokho kuwumphumela wemithetho yamandla adonsela phansi, izimo zokuqala zokwakheka kohlelo lwelanga, kanye nokusebenzisana okuyinkimbinkimbi phakathi kwamaplanethi nezinye izidalwa zasezulwini. Ukuqonda ukuthi kungani imijikelezo izinzile—futhi lapho iba engazinzile—kusiza ososayensi ukuhlola ikusasa lohlelo lwelanga, ukuchaza ukuba khona kwamaplanethi angaphandle, ngisho nokulinganisa amathuba amaplanethi angahlalwa.
Kusho ukuthini ukuzinza kwe-orbital?
Ngokwesayensi yezinkanyezi, "umjikelezo ozinzile" kusho ukuthi iplanethi ingaqhubeka nokujikeleza inkanyezi yayo isikhathi eside kakhulu ngaphandle kokubona izinguquko ezinkulu ezingayibangela ukuba iphume ohlelweni, ishayisane, noma ibhekane nokuphazamiseka okukhulu esimweni sayo sokuzungeza. Ukuzinza akusho ukuthi umjikelezo ozungeza ngokuphelele. Amaplanethi amaningi anemizila ejikelezayo, kodwa ahlala eqinile uma nje imingcele yawo yokuzungeza (njengebanga elimaphakathi nenkanyezi, ukungavamile, kanye nokuthambekela) ishintshashintsha ngaphakathi kwemingcele ethile.
Ukuzinza kungahlukaniswa ngezinhlobo eziningana. Ukuzinza kwesikhathi esifushane kuchaza imijikelezo engaphazamiseki ngokushesha ngezikali zamakhulu kuya ezinkulungwaneni zeminyaka. Ukuzinza kwesikhathi eside kubhekana nokuphikelela kwemijikelezo ngezikali zezigidi kuya ezigidigidini zeminyaka. Kukhona nomqondo wokuzinza "okungahlelekile" kuma-dynamics: i-orbit ingaqhubeka isikhathi eside, kodwa ibucayi kakhulu ezinguqukweni ezincane, okwenza ukuziphatha kwayo kube nzima ukubikezela ngokuningiliziwe esikhathini eside.
I-physics eyisisekelo: amandla adonsela phansi kanye nemithetho kaKepler
Ukuzinza kwe-orbital kuvela emthethweni kaNewton wamandla adonsela phansi: imizimba emibili idonselana ngamandla ancike kubuningi bayo futhi yehla ngesikwele sebanga eliphakathi kwayo. Kusukela kulo mthetho, uJohannes Kepler wakha imithetho emithathu yokuhamba kwamaplanethi echaza imijikelezo ye-elliptical, ubudlelwano phakathi kwesikhathi nebanga, kanye nokushintshashintsha kwejubane leplanethi emjikelezweni wayo.
Uma bekukhona izinto ezimbili kuphela—isibonelo, iLanga kanye neplanethi eyodwa—khona-ke ukunyakaza kwamaplanethi bekuzolandela isisombululo sezibalo esihlelekile nesizinzile. Amandla awo kanye nomfutho we-angular bekuzogcinwa, ngakho-ke ukuzungeza kwawo bekuzohlala kungashintshi. Kodwa uhlelo lwangempela lwelanga alulula kangako. Amaplanethi amaningi, amasathelayithi, ama-asteroid, kanye nama-comet kuyathintana. Lokhu kuphazamiseka okuncane okungapheli, okunamandla adonsela phansi yikona okwenza ucwaningo lokuzinza kwe-orbital lube mnandi futhi luyinkimbinkimbi.
Ukuphazamiseka kwamandla adonsela phansi phakathi kwamaplanethi
Amaplanethi awathonywa yiLanga kuphela kodwa futhi nokudonswa kwamandla adonsela phansi kwamanye amaplanethi. Isibonelo, isisindo esikhulu sikaJupiter siphazamisa imijikelezo yama-asteroid ebhande le-asteroid, okudala "izikhala zaseKirkwood" - izindawo ezingenalutho lapho ukuzwelana kwe-orbital kubangela khona ukuthi ama-asteroid akhukhulwe noma ashintshelwe emijikelezweni ehlukene. IJupiter iphinde ithonye umjikelezo weMars futhi, ngokungaqondile, ingabangela izinguquko ezincane emijikelezweni yamaplanethi angaphakathi ngochungechunge lokuxhumana kwamandla adonsela phansi.
Lokhu kuphazamiseka kuvame ukuba kuncane ngomjikelezo ngamunye, kodwa kuyaqongelela. Ngokuhamba kwesikhathi, kungashintsha ukungafani (izinga le-ellipticality) kanye nokuthambekela (ukuthambekela komjikelezo). Uma lezi zinguquko zinkulu ngokwanele, umjikelezo ungaba ongazinzile, isibonelo ngokwandisa amathuba okushayisana noma ukushintsha ibanga lawo kusuka enkanyezini ephethe.
Umsindo we-orbital: kokubili i-stabilizer kanye ne-disruptor
I-orbital resonance yenzeka lapho isilinganiso sezinkathi ze-orbital zezinto ezimbili siyinombolo elula enengqondo, njengo-2:1 noma u-3:2. Ama-resonance angadala amaphethini aqinile, aphindaphindayo ethonya lamandla adonsela phansi. Ngokuthakazelisayo, ama-resonance angaba ukuzinza noma okuphazamisayo.
Isibonelo sokuzwana okuzinzile yi-resonance ye-Laplace phakathi kwezinyanga eziningana ze-Jupiter, njenge-Io, i-Europa, ne-Ganymede. Lokhu kuzwana kugcina ukunyakaza kwazo okuvamile futhi kuvimbela ukuzungeza kwazo ukuthi zingabi yisiphithiphithi. Ngakolunye uhlangothi, ukuzwana okuphazamisayo kungandisa ukungezwani kwe-asteroid, okubangela ukuthi ukujikeleza kwayo kuhlangane nokujikeleza kweplanethi, okwenza kube sengozini yokudonswa ngaphandle noma ukushayisana nayo.
Esimisweni sonozungezilanga, ama-resonance nawo adlala indima ekwakhekeni kwezakhiwo ezifana nama-planetary rings kanye nokusatshalaliswa kwenani elincane lemizimba. Ukuzinza kwemizila yamaplanethi kuvame ukuxhomeke ekugwemeni ama-resonance athile angakhulisa ukuphazamiseka.
Indima yokushabalaliswa kwamandla kanye nethonya lolwandle
Ngaphandle kwamandla adonsela phansi amsulwa, kunezinqubo zokuhlakazeka kwamandla—ngokwesibonelo, ngenxa yamandla olwandle. Amaza avela ngoba ukudonsa kwamandla adonsela phansi akulingani ezinhlangothini eziseduze nezikude zento. Ezinhlelweni zezinkanyezi zamaplanethi, amaza angashintsha ukujikeleza nokujikeleza.
Emaplanethini aseduze nezinkanyezi zawo, amandla olwandle angabangela ukuthi iplanethi ivaleke, ukuze uhlangothi olulodwa luhlale lubheke inkanyezi. Ngokuhamba kwesikhathi, amaza angahambisa iplanethi kancane kancane: amanye ajikeleza aye enkanyezini, amanye ahambe, kuye ngokusatshalaliswa komfutho we-angular kanye nemininingwane yangaphakathi yenkanyezi neplanethi. Le nqubo ibalulekile ekuqondeni ukuzinza "kwamaJupiter ashisayo," noma amaplanethi aseduze nezinkanyezi ezinhlelweni ze-exoplanet.
Isiphithiphithi ekushintsheni kwesimiso sonozungezilanga
Nakuba uhlelo lwelanga lubonakala luhlelekile, ngokwezibalo, izinhlelo eziningi zomzimba zingabonisa ukuziphatha okuphazamisayo. Lokhu kusho ukuthi ukulingisa okubili okucishe kufane kungadala izindlela ezahlukene zokuziphendukela kwemvelo kwe-orbital ngokuhamba kwesikhathi. Lokhu kulinganiswa ngemibono efana "nesikhathi sikaLyapunov," isilinganiso sesikhathi lapho izibikezelo ezinemininingwane ziba nzima njengoba amaphutha amancane ekhula.
Izifundo eziningana zisikisela ukuthi ukujikeleza kweMercury kunethuba lokungazinzi esikalini seminyaka eyizigidigidi, ikakhulukazi ngenxa yokusebenzisana okuguquguqukayo neJupiter neVenus. Nakuba kungenakwenzeka, isimo esibi kakhulu singandisa ukungafani kweMercury kuze kube sezingeni lokuthi ingqubuzane neVenus noma iwele ngisho naseLangeni. Lokhu kusikisela ukuthi ukuzinza kokujikeleza akusona isiqiniseko esiphelele, kodwa kunalokho kuyithuba lesikhathi eside kakhulu.
Kungani uhlelo lwelanga luzinzile?
Kunezizathu eziningana eziyinhloko zokuthi kungani isimiso sethu sonozungezilanga siye sahlala sizinzile phakathi nesikhathi saso eside sokuphila:
1. Ubunzima obuphezulu beLanga: ILanga liqukethe ngaphezu kuka-99% wobunzima besimiso sonozungezilanga, ngakho-ke insimu eyinhloko yamandla adonsela phansi inamandla kakhulu futhi isiza ukugcina amaplanethi eboshiwe.
2. Amabanga amakhulu phakathi kwamaplanethi: Amaplanethi amakhulu aqhelelene kakhulu uma kuqhathaniswa nobukhulu bezindlela zawo zokujikeleza, ngakho ukuphazamiseka okuqondile okunamandla akuvamile.
3. Ukusatshalaliswa komfutho we-angular: Uhlelo lwelanga lwakhiwa kusuka kudiski ye-protoplanetary eyayinikeza isiqondiso sokujikeleza esifanayo kanye ne-coplanar orbits ngokuvamile.
4. Ukuntuleka kokuhlangana okusondelene njalo: Amaplanethi awaphambani kakhulu izindlela zokujikeleza komunye nomunye, ngakho-ke ukushayisana okukhulu kuba yizenzakalo ezingavamile ngemva kwesigaba sokuqala sokwakheka.
Kodwa-ke, lokhu kuzinza akusho ukungabikho koshintsho. Amapharamitha okujikeleza kweplanethi ashintsha kancane kancane, ethonya isimo sezulu samaplanethi afana noMhlaba ngemijikelezo yaseMilankovitch (izinguquko ekungajwayelekile, ukuthambekela kwe-axial, kanye nokuqala kwe-precession) okuhambisana nezikhathi zeqhwa.
Ukuzinza kwe-orbital ezinhlelweni zangaphandle kwelanga
Ukutholakala kwezinkulungwane zamaplanethi angaphandle kubonisa ukuthi isimiso sethu selanga akuyona yodwa imodeli. Izinhlelo eziningi zamaplanethi zinamaplanethi amakhulu aseduze kakhulu nezinkanyezi zawo, noma amaplanethi amaningi azungeza eduze kakhulu. Ukuqina kwezinhlelo ezinjalo kuvame ukunqunywa ukufana kanye nokufuduka kwamaplanethi emlandweni wawo wokuqala. Amaplanethi angashintsha izikhundla ngenxa yokusebenzisana namadiski egesi nothuli, bese "evalelwa" kuma-resonances awenza angasondeli kakhulu komunye nomunye.
Ezifundweni ze-exoplanet, ukuzinza kwe-orbital kusetshenziswa njengethuluzi lokuhlola ukuthi ngabe ukuhlelwa kwamaplanethi okutholiwe kunengqondo yini. Uma ukucushwa okuthile kungazinzile ekulingiseni, ososayensi bangaphetha ngokuthi kunezinye iziplanethi ezingakatholakali, noma ukuthi amapharamitha e-orbital alinganisiwe adinga ukulungiswa.
Isiphetho
Ukuzinza komjikelezo weplanethi kuwumphumela wokulinganisela phakathi kokubopha kwamandla adonsela phansi, ukuphazamiseka kwamaplanethi, ukuxokozela, kanye nezinqubo zokuhlakazeka kwamandla ezifana namaza. Ezinhlelweni ezilula zemizimba emibili, imijikelezo ingaba yinto ezinzile futhi ebikezelwayo. Kodwa-ke, ohlelweni lwelanga nakwezinye izinhlelo zeplanethi eziyinkimbinkimbi, ukuzinza kuba yindaba yezinguquko zemizimba eminingi, okungabonisa ukuziphatha okuphazamisayo ezikalini zesikhathi eside kakhulu. Noma kunjalo, uhlelo lwethu lwelanga luye lwabonisa ukuzinza okuphawulekayo eminyakeni eyizigidigidi, okuvumela ukuphila ukuba kuchume eMhlabeni.
Ukufunda ukuzinza kwe-orbital akukhona nje ukuqonda ukunyakaza kwamaplanethi; kumayelana nokulandelela umlando wokwakheka kwesistimu yamaplanethi, ukubikezela ukuvela kwawo esikhathini esizayo, kanye nokufuna izimo ezivumela amaplanethi ukuthi ahlale endaweni okuhlalwa kuyo. Ngokuthuthuka kokulingisa kwamakhompyutha kanye nedatha yokubuka kumaplanethi angaphandle, lesi sihloko siyaqhubeka nokuguquka futhi siba sibaluleke kakhulu ekuqondeni indawo yethu endaweni yonke.
