Amaplanethi Amancane, Izinkanyezi Ezinomsila Nomhlaba—Ingabe Kuzoshayisana?

‘Entathakusa ngo-June 30, kwenzeka isimanga kuleli dolobhana laseSiberia. Phezulu emkhathini, izisebenzi zabona into ethile ekhazimulayo; yayikhazimula ngendlela exhophayo. Esibhakabhakeni, kwakunefu elincane elimnyama elalihambisana nale nto ekhazimulayo. Lapho le nto ekhazimulayo isondela emhlabeni, kwabonakala sengathi iphahlazeka iba izicucu. Kwaqubuka ifu elikhulu lentuthu emnyama, kwezwakala ukuqhuma okukhulu, njengokungathi kudilika amadwala. Kwandindizela izakhiwo, futhi kwaqubuka ilangabi elikhulu eliya emafwini. Izakhamuzi zaphumela emigwaqweni zethukile. Izalukazi zakhala izinyembezi; wonke umuntu wayecabanga ukuthi ukuphela komhlaba sekufikile.’—Umbiko ofingqiwe owavela ephephandabeni i-Sibir, lase-Irkutsk, eRussia, ngo-July 2, 1908.

LABO BANTU abaqaphelanga ukuthi kwakuqhume into evela ezulwini endaweni yakubo. Namuhla, eminyakeni engaphezu kwengu-90 kamuva, esinye sezibikezelo ezixaka kakhulu zokuphela kweplanethi yethu sihlanganisa inhlekelele eyobangelwa iplanethi encane noma inkanyezi enomsila. Kunezifushaniso ezinjengesithi NEO (near-earth objects [izinto ezisondele emhlabeni]) nesithi PHO (potentially hazardous objects [izinto ezingadala ingozi]) eziphathelene nezibikezelo eziyinhlekelele zokuthi umhlaba uyobhujiswa ukungqubuzana nezinto ezihamba emkhathini. I-Hollywood iye yasizakala ngalezi zimo ezisatshwayo ukuze izuze imali ngokwenza amabhayisikobho anjengethi Deep Impact nethi Armageddon.

Kunamathuba angakanani okuthi wena noma izingane zakho niyobhujiswa umlilo ovela ezulwini? Ingabe kufanele ulindele ukuthi izinguzunga zensimbi neqhwa ziyowela egcekeni lakwakho maduzane? Uma uhlala ngasogwini, ingabe umuzi wakho uyokhukhulwa igagasi elikhulu eliyobangelwa ukuwela kweplanethi encane olwandle?

Uzungeza Phakathi Kwemfucumfucu Yamaplanethi

Isimiso sethu sonozungezilanga siqukethe okungaphezu nje kwelanga, amaplanethi angu-9 kanye nezinyanga zawo. Izinkanyezi ezinomsila (eziyinhlanganisela yeqhwa nothuli), ama-asteroid (amaplanethi amancane) kanye nama-meteoroid (ngokuvamile ayizingcezu zamaplanethi amancane) nako kuzungeza esimisweni sonozungezilanga. Sekuyisikhathi eside ososayensi bazi ukuthi umhlaba ungase ushayisane nezinto ezivela emkhathini. Singabona nje ngokubheka inyanga enemigodi ukuthi siphila endaweni eminyene. Ukube ubungekho umoya osemkhathini nobuso bomhlaba bungashintshi njalo ngenxa yokuhamba kwezingqimba zawo nokukhukhuleka kwenhlabathi, ubuso beplanethi yethu ngabe bunemigodi njengobenyanga.

Ososayensi balinganisela ukuthi kubonakala izinkanyezi ezitshuzayo ezingaba yizigidi ezingu-200 emkhathini womhlaba nsuku zonke. Izinto eziningi ezingena emkhathini zincane futhi ziyasha ziphele zingazange zibonakale. Nokho, ezinye zalezi zinto azishi ngokuphelele lapho zingena emkhathini futhi umoya unciphisa isivinini sazo sibe amakhilomitha angu-320 ngehora. Izingxenye zazo ezisalayo ziwela enhlabathini zingama-meteorite. Ngenxa yokuthi eziningi ziwela olwandle noma ezindaweni ezingenamuntu, azivamile ukulimaza abantu. Kulinganiselwa ukuthi izinto ezingena emkhathini wethu zinezela amakhulu amathani esisindweni somhlaba nsuku zonke.

Ngaphandle kwalokho, izazi zezinkanyezi zilinganisela ukuthi kungenzeka kunamaplanethi amancane angaba ngu-2 000 angaphezu kwekhilomitha ubukhulu anqamula noma asondela emzileni wokuzungeza komhlaba. Ziye zathola futhi zalandelela angaba ngu-200 kuphela. Futhi kunamaplanethi amancane angaba yisigidi anobukhulu obungamamitha angu-50 asondela emzileni wokuzungeza komhlaba ngendlela eyingozi. Amaplanethi amancane anjalo angafinyelela enhlabathini futhi abange umonakalo. Into encane kangako etshuzayo inamandla angaba amathani ayizigidi eziyishumi—amandla alingana nebhomu elikhulu lenuzi. Nakuba umkhathi womhlaba ungasivikela ekushayisaneni nezinto ezincane, awunakuzinqanda lezo ezinamandla angamathani ayizigidi eziyishumi noma ngaphezulu. Abanye abacwaningi bathi izibalo zibonisa ukuthi singalindela ukushayisana nento esemkhathini enamandla angamathani ayizigidi eziyishumi okungenani kanye njalo ngemva kweminyaka eyikhulu. Ngokwezinye izibalo, linye ithuba lokushayisana nezinto ezinobukhulu obungaba yikhilomitha eminyakeni engu-100 000.

Imigodi, Ukuqhuma Nokushayisana Okuyibika

Akuyona into enzima ukukholelwa ukuthi iplanethi yethu iye yashayisana nezinto ezinkulu ezivela emkhathini esikhathini esidlule. Ubufakazi balokhu bungatholakala emigodini engaphezu kwengu-150 esebusweni bomhlaba. Eminye mikhulu, kanti eminye ibonakala lapho umuntu esendizeni noma ibonakale ngesiphuphutheki kuphela, kanti-ke eminye seyagqibeka kudala noma isekujuleni kolwandle.

Omunye wale migodi odume kakhulu, owaziwa ngokuthi i-Chicxulub, ungamakhilomitha angu-180 ubukhulu. Lo mgodi omkhulu osemaphethelweni asenyakatho neYucatán Peninsula, eMexico, kukholelwa ukuthi wabangelwa inkanyezi enomsila noma iplanethi encane enobubanzi obungamakhilomitha ayishumi. Abanye bathi ukushintsha kwesimo sezulu okwabangelwa yilokhu kwaqothula izibankwakazi nezinye izilwane zasezweni nezasolwandle.

E-Arizona, e-U.S.A., i-meteorite yensimbi yavula iMeteor Crater enkulu—umgodi ongaba amamitha angu-1 200 ububanzi namamitha angu-180 ukujula. Ungaba ngakanani umonakalo uma i-meteorite enjalo ingawela edolobheni? Umbukiso othandwayo e-American Museum of Natural History, eNew York City, ubonisa ukuthi uma into enjalo ibingawela eManhattan, lelo dolobha elinabantu abaningi belingabhujiswa ngokuphelele.

Ngo-June 30, 1908, iplanethi encane noma isigaxa senkanyezi enomsila okulinganiselwa ukuthi yayingamamitha ayikhulu ubukhulu yangena itshuza emkhathini futhi yaqhuma ebangeni elingamakhilomitha angu-8 enhla nendawo eyayingenamuntu eTunguska, eSiberia, njengoba kushiwo esethulweni. Lokhu kuqhuma, okwalinganiselwa emandleni angamathani ayizigidi ezingu-15, kwaqothula indawo engamakhilomitha-skwele angu-2 000, kwabhubhisa izihlahla, kwathungela imililo, kwabulala nezinyamazane. Kwakuyofa abantu abangaki ukube indawo okwenzeka kuyo ukuqhuma kwakuyindawo enabantu abaningi?

Ngo-July 1994, izibonakude kuwo wonke umhlaba zazigxilé kuyi-Jupiter lapho izingcezu zenkanyezi enomsila i-Shoemaker-Levy 9 zishayisana naleyo planethi. Imigodi yesikhashana eyaba khona kuyi-Jupiter iyohlala ikhumbuleka ezingqondweni zalabo abakubona ngawabo lokho kungqubuzana. Ukubuka i-Jupiter ishayeka ngokuphindaphindiwe kwashiya ochwepheshe nabantu abavamile bezibuza ukuthi kwakuyokwenzekani ukube kwakuwumhlaba owawushayisane naleyo nkanyezi enomsila.

Imibono Yenhlekelele

Benexhala, ososayensi baye bacabangela imiphumela eyinhlekelele engaba khona uma iplanethi yethu ingqubuzana nenkanyezi enomsila noma neplanethi encane. Imiphumela yangaleso sikhathi yokungqubuzana okukhulu bacabanga ukuthi ibingaba njena. Okokuqala bekungaqubuka ingqumbi yamadwala nothuli olukhulu. Imfucumfucu edilikayo ibiyobangela amalangabi e-meteor abeyokwenza umkhathi ushise futhi okhele amahlathi nezinkangala, abulale izilwane eziningi ezweni. Uthuli olusala emkhathini isikhathi eside beluyosibekela ukukhanya kwelanga, lunciphise amazinga okushisa futhi luthiye i-photosynthesis ngenxa yobumnyama. Ukungenzeki kwe-photosynthesis nakho bekuyobangela ukunqamuka kwesimiso sokudla olwandle, obekuyobulala izilwane eziningi zasolwandle. Ngokwalo mbono, le nhlekelele yendawo ezungezile ibiyohambisana nemvula ye-asidi embulungeni yonke nokuqothulwa kongqimba lwe-ozone.

Uma iplanethi enjalo encane ibingawela olwandle, ibingabangela amagagasi amakhulu, angacekela phansi yonke into. La magagasi abengafinyelela kude kunamagagasi okuqala futhi abengabangela umonakalo omkhulu ezindaweni ezisogwini eziqhele ngezinkulungwane zamakhilomitha. Isazi sezinkanyezi uJack Hills sithi: “Bekuyosala udaka lodwa esikhundleni samadolobha.”

Nokho, umuntu kufanele aqaphele lapho egomela ngaleyo ndlela. Imibono eminingi enjalo imane nje iwukucabangela. Ngokusobala, akukho muntu owake wabona noma wahlola iplanethi encane lapho ishayisana nomhlaba. Futhi, imithombo yezindaba yanamuhla eshukunyiswa yimizwelo ibhala izihloko zezindaba eziyihaba, ezisekelwe ekwazisweni okungaphelele noma okunganembile nakancane. (Bheka ibhokisi elingenhla.) Eqinisweni, kuthiwa amathuba okubulawa yinto evela emkhathini mancane kakhulu kunamathuba okufa engozini yemoto.

Yini Okufanele Yenziwe?

Ochwepheshe abaningi bakholelwa ukuthi indlela engcono kakhulu yokugwema inhlekelele yokushayisana nenkanyezi enomsila noma neplanethi encane iwukuciba irokhethi eyoyikhinyabeza, futhi okungenani, iyibhekise kwenye indawo. Uma iplanethi incane futhi ibonakala kusasele iminyaka eminingi ngaphambi kokuba ishayisane nomhlaba, kungase kwanele ukuthumela le rokhethi.

Nokho, uma kubhekwa izinto ezinkulu kakhulu ezingase zishayisane nomhlaba, abanye ososayensi bahlongoza ukuba kusetshenziswe izikhali zenuzi. Esimweni esinjalo, kucatshangwa ukuthi ibhomu lenuzi elicushwe kahle lingashaya leyo planethi encane iphumele komunye umzila ophephile, kuvimbele ukungqubuzana. Ubukhulu beplanethi kanye nokuthi isondele kangakanani emhlabeni bekunganquma ukuthi kudingeka ibhomu lenuzi elinamandla kangakanani.

Inkinga iwukuthi azikho kulezi zinyathelo zokuphepha ebezingaphumelela ngaphandle kwesixwayiso esifanele kusasele isikhathi. Izinhlangano zezazi zezinkanyezi ezinjenge-Spacewatch ne-Near Earth Asteroid Tracking zizinikezele ngokukhethekile ekufuneni amaplanethi amancane angase angqubuzane nomhlaba. Abantu abaningi banomuzwa wokuthi kumelwe kwenziwe okwengeziwe ngale ndaba.

Kuyavunywa ukuthi abantu abangaphelele banolwazi olulinganiselwe ngokuphathelene nokuthi lezi zinto ezihamba emkhathini zikuyiphi indawo nokuthi zihamba kanjani. Kodwa asikho isidingo sokukhathazeka ngokweqile noma sokwesaba ngokweqile usongo lokuthi ikusasa lokuphila emhlabeni lisengozini. Isiqinisekiso esigcwele sokuthi ayikho iplanethi encane noma inkanyezi enomsila eyovunyelwa ukuba ibhubhise konke ukuphila emhlabeni sivela kuMdali wendawo yonke, uJehova uNkulunkulu.a IBhayibheli liyasiqinisekisa: “Abalungileyo bazakudla ifa lomhlaba, bahlale kuwo njalonjalo.”—IHubo 37:29; Isaya 45:18.

[Umbhalo waphansi]

[Ibhokisi ekhasini 27]

Indaba Ye-1997 XF11

Ngo-March 12, 1998, kwasakazwa izindaba ezimbi embulungeni yonke: Iplanethi encane eyikhilomitha nesigamu ubukhulu yayiphokophele emhlabeni futhi yayizofika “ngoLwesine,” ngo-October 26, 2028. Le planethi encane, eyabizwa ngokuthi yi-1997 XF11, yatholwa ngo-December 6, 1997, yisazi sezinkanyezi uJim Scotti, weqembu le-Spacewatch le-University of Arizona. Besebenzisa ukwaziswa kwesikhathi esidlule nezinto ezintsha abazitholile, ososayensi baseHarvard-Smithsonian Center for Astrophysics bakhipha ukwaziswa abanye abakusebenzisela ukubikezela ukuthi umzila le planethi encane ezungeza kuwo uqhele cishe ngamakhilomitha angu-50 000 emhlabeni—okuyibanga elincane kakhulu ngokwezazi zezinkanyezi, noma “ibanga okungenathuba lokuba igeje kulo.” Imibiko yethelevishini yayigcwele imifanekiso esabisayo ebonisa ukuthi le planethi encane iyoshayisana kanjani nomhlaba. Khona-ke, ngemva nje kosuku olulodwa, ingozi yayingasekho. Ukwaziswa okusha nezibalo kwabonisa ukuthi le planethi encane yayizogeja umhlaba ngamakhilomitha angu-1 000 000. Lokho kwakuseseduze kunanoma iyiphi iplanethi encane eyake yabonwa ngaphambili, kodwa kwakuyibanga eliphephile. Imithombo yezindaba yanyathelisa izihloko ezinkulu ezinjengesithi “Kulungile Phela, Bebegejile.”

[Izithombe ekhasini 26]

1. Inkanyezi enomsila iHalley’s

2. Inkanyezi enomsila i-Ikeya-Seki

3. Iplanethi encane i-951 Gaspra

4. IMeteor Crater—umgodi ongaba amamitha angu-1 200 ububanzi namamitha angu-180 ukujula

[Imithombo]

Courtesy of ROE/Anglo-Australian Observatory, photograph by David Malin

NASA photo

NASA/JPL/Caltech

Photo by D. J. Roddy and K. Zeller, U.S. Geological Survey

[Umthombo Wesithombe ekhasini 25]

NASA photo