Ukubona Okungabonakali—Isayensi Yokubona
INDAWO enhle, ukushona kwelanga okukhazimulayo, imbali ethandekayo—konke kuyimibukwane emihle okujabulisayo ukuyibona. Nakuba singavamile ukucabanga ngalokho okuhilelekile ekuboneni, ngokuqinisekile siyajabula ngokuthi siyakwazi ukubona.
Njengoba iso limangalisa, lokho esikwazi ukukubona ngeso lenyama kumane nje kuyingxenye yalokho okukhona okungase kubonwe. Ngokusetshenziswa kwamathuluzi okubona—kusukela engilazini ekhulisayo evamile kuya kuzibona-kude, izibona-khulu, amakhamera akhethekile, amaspectroscope, njalonjalo—isayensi yokubona, njengoba isifundo sokukhanya sibizwa kanjalo, iye yalwandisa kakhulu ulwazi lwethu ngathi ngokwethu nangezwe elisizungezile.
Nakuba kungenzeka ujwayelene namanye alamathuluzi okubona, ingabe uyazi ukuthi asebenza kanjani? Ngokwesibonelo, kungani ingilazi ekhulisayo ikhulisa? Yini eyenza elinye ithuluzi libonise izwe lezilwanyana ezincane futhi elinye libonise umkhathi omkhulu wendawo yonke? Sekuyisikhathi eside isayensi yokubona iwumkhakha wesifundo esihlaba umxhwele.
Isici Esiyisisekelo
Ingabe wake wayisebenzisa ingilazi ekhulisayo ephathwa ngesandla ukuze ushise imbobo esiqeshini sephepha ngokuqondisa umsebe wokukhanya kulo? Lokho owawukuphethe lapho kwakuyithuluzi lokubona lohlobo oluvame kakhulu—ilens. Lelochashaza elincane elisephepheni eqinisweni laliwumfanekiso welanga ovezwa ilens evamile owawuyiphethe. Ukugxilisa wonke amandla akulowomsebe wokukhanya endaweni eyodwa encane kwayenza yashisa ngokwanele ukuba ishise iphepha.
Enye ilens abaningi abajwayelene nayo yileyo esekhamereni. Kungenzeka uyazi ukuthi igxilisa ukukhanya okuvela kulokho okuthwetshulwayo ukuze yakhe umfanekiso efilimini yesithombe esithathwayo. Ngokuyisisekelo, yilokho ilens ekwenzayo. Iletha ukukhanya ndawonye ukuze yakhe umfanekiso wobukhulu nokugqama okufanelekile ukuze kukwazi ukubonakala noma kurekhodwe. Kodwa ilens ingakugoba kanjani ukukhanya futhi ikulethe ndawonye, noma ikugxilise ndawonye? Impendulo iphethwe isici sokubona esibizwa ngokuthi irefraction.
Lapho ufaka induku echibini lamanzi, yini oyibonayo? Induku ayibonakali yini igobekile endaweni lapho ingena khona emanzini? Lesenzakalo esivamile kodwa esixakayo sibonisa ukuthi lapho umsebe wokukhanya udlula kwenye into uya kwenye, njengalapho usuka emanzini uya emoyeni, awuqhubeki ngomugqa oqondile; uyagobeka ngaphandle kokuba ushaye umngcele ngendlela evundlile. Lokhu yilokho izazi zesayensi ezikubiza ngokuthi irefraction. Isilinganiso ukukhanya okugobeka ngaso sixhomeke entweni okudlula kuyo—umoya, amanzi, uwoyela, ingilazi, njalonjalo—kanye nasohlangothini ukukhanya okuvela kulo, okuwukuthi, uhlangothi oluphakathi komsebe wokukhanya nohlangothi oluqondile endaweni okungena kuyo.
Ake ubheke ilens yekhamera futhi. Uyophawula ukuthi ubuso belens abusona isicaba kodwa bugobile njengobuso bembulunga. Manje ake ucabange ngomsebe wokukhanya oza kuyo uvela ebangeni elithile. Phakathi nendawo, ukukhanya kumi kuvundlile ebusweni belens; ngaleyondlela kuhamba kuqonde ngaphandle kokuba ukugobeka kwemisebe kwenzeke. Uhlangothi ukukhanya okuvela kulo lukhula ngokuqhubekayo ngokuyela ngasekupheleni kwelens. Lokhu kusho ukuthi ukugobeka kwemisebe okubangelwa ilens kukhulu nasendaweni eqhelile phakathi nendawo lapho ukukhanya kuhlaba khona. Ngenxa yalokhu, yonke imisebe ephuma endaweni efanayo ohlangothini olulodwa lwelens eklanywe ngokufanelekile iyohlangana, noma igxiliswe, ngakolunye uhlangothi ukuze yakhe umfanekiso.
Ukuklama Isimiso Sokubona
Nokho, okwenza lendaba ibe inkimbinkimbi ukuthi ukukhanya kwemibala ehlukahlukene, noma kwamaza obude obuhlukahlukene, kugoba ngamazinga ahlukahlukene. Yingakho iprism isakaza umsebe wokukhanya kwelanga kube ngemibala yakho, yakhe uthingo. Lokhu yilokho kanye okwenzekayo ngelens evamile; lowomfanekiso ngokuvamile unemisebe enemibala, ngaleyondlela egwegwile.
Lenkinga inganqotshwa ngokuklama ngokucophelela. Ngokwesibonelo, izazi zesayensi ziyazi ukuthi isilinganiso samakhemikhali sengilazi esisetshenziswe kuyilens siyolungisa izimfanelo zayo zokugoba imisebe. Ngokwenza isimiso samalens enziwe ngezinhlobo ezihlukahlukene zengilazi futhi agobeke ngokuhlukahlukene, umklami angagcina ukufiphala nokugwegwa kukuncane.
Nokho, ukuklama isimiso esinjalo akulula. Kwakuvame ukuhilela abantu abaningi abenza ukubala okukhandlayo amasonto amaningi ngisho nezinyanga ukuze kuvezwe umklamo. Namuhla, amacomputer asetshenziselwa ukubala wonke amazinga ahlukahlukene angenzeka ezinhlangothini imisebe yokukhanya evela kuzo, ibanga phakathi kwamalens, ukugoba kwelens ngayinye, nezinye izici eziningi. Lecomputer ihlelwe ukuba ikhethe inhlanganisela eyophumela esimisweni sokunemba okukhulu kakhulu.
Ilens enhle yekhamera ingase ibe nezingxenye ngazinye ezisukela kwezine kuya kweziyisikhombisa, noma ngaphezulu, nobuso obungakwazi ukubona ezinkulungwaneni eziyishumi zemilimitha. Ingxenye ngayinye kumelwe ifakwe ihlobane ncamashi nezinye. Ukuze kutholakale ukukhanya okuningi ngangokunokwenzeka, ububanzi bengxenye ngayinye kumelwe bube bukhulu ngokwanele. Zonke lezinto kuyabiza ukuzenza, futhi lokho kuchaza isizathu sokuba ikhamera ephambili ibize kangaka. Ngokwesibonelo, enye yamakhamera asetshenziswa umkhumbi-mkhathi ingathwebula imininingwane esemhlabeni engamamitha angu-10 ububanzi emakhilomitheni angu-240 phezulu emkhathini. Lekhamera inelens enezingxenye eziyisishiyagalombili, futhi ibiza amarandi angu-24 750 000!
Ukubona Okungabonakali
Ake ucabange ngalokho okuhilelekile ekuklameni, ekukhiqizeni, nasekuhloleni isimiso sokubona esisetshenziswa kusibona-kude esiyosivumela ukuba sihlole indawo yonke yethu enkulu, emangalisayo. Izinkanyezi ezikude zifiphele kangangokuthi iningi lazo alibonakali ngeso lenyama. Isibona-kude siyoqoqa ukukhanya okuningi ngangokunokwenzeka kulezinkanyezi ezikude, sikuqondise endaweni eyodwa, futhi sakhe umfanekiso obonakalayo.
Izibona-kude eziningi zokubona zisebenzisa isibuko esigobile ngaphakathi ukuze ziqoqe imisebe yokukhanya okufiphele. Ngokwesibonelo, isibona-kude esidumile iHale esiseNtabeni iPalomar sinesibuko esingamamitha ayisihlanu ububanzi futhi singakwazi ukuhlola kumalight-year (isivinini sokukhanya) ayizinkulungwane zezigidi eziningana. Nakuba simangalisa, isibona-kude iHale manje sesiye sadlulwa esinye esiphezu kweMauna Kea yaseHawaii. Lesibona-kude sinesibuko esingamamitha angu-10—esinamandla okuqoqa ukukhanya aphindwe kane kunesibona-kude esisePalomar. Eqinisweni, sinamandla kangangokuthi “singavumela umuntu abone ukukhanya kwekhandlela elilodwa elisenyangeni,” kusho uHoward Keck, umongameli wenhlangano eyanikela ngamarandi angu-192 500 000 ekuxhaseni ukwakhiwa kwaso.
Esikhathini esithile amehlo ezazi zezinkanyezi aye athi njó kusibona-kude sohlobo oluhlukile: iHST (Hubble Space Telescope) ebiza u-R4 400-000 000. Njengoba sacitshwa umkhumbi-mkhathi, sizungeza umhlaba ebangeni elingamakhilomitha angu-500 ukuya emkhathini. Ngaphandle kokuphazanyiswa umoya womhlaba, singabona kahle kangangokuthi, ngokwendlela okwashiwo ngayo, amandla aso okucacisa “alingana nokukwazi ukuhlukanisa isibani semoto sobunxele kwesokudla ebangeni eliqhele ngama[khilomitha angu-4 000],” kusho umagazini iSky & Telescope. Ukuze kufinyelelwe kulelizinga lokucacisa, ubuso besibuko saso esilinganiselwe esingamamitha angu-2,4 kwadingeka bukwazi ukubona emakhulwini ezinkulungwane eziyisihlanu zemilimitha. Nokho, okwabadumaza bonke ukuthi imifanekiso yokuqala iHST eyayithumela emuva ivela emkhathini yayingacacile, ngokusobala ngenxa yephutha langesikhathi yenziwa. “Ingxenye yefilimu-mbumbulu elingana nohlamvu lwesihlabathi,” kusho umbiko kuyiNew Scientist, “yaphuma emshinini wokulinganisa phakathi nokwenziwa kwesibuko esiyinhloko sesibona-kude. Ngenxa yalokho isibuko sasiyisicaba kakhulu.” Ngokusobala, ngisho nobuchwepheshe obuseqophelweni eliphakeme kakhulu bunephutha!
Sesingasuka ekuboneni kude ngesibona-kude, siphendukele ekuboneleni eduze ngesibona-khulu. Izibona-khulu zakuqala ziyefana nengilazi ekhulisayo. Ekhulwini le-17 leminyaka, izibona-khulu eziyinkimbinkimbi zaqala ukusetshenziswa, lapho umfanekiso owawakhiwa ilens eyodwa wawukhuliswa futhi enye ilens. Ilens yokuqala ibizwa ngokuvamile ngokuthi eyalokho okubukwayo ngoba iqondiswa kulokho okubukwayo, futhi ilens yesibili, indawo yeso.
Ukuze isibona-khulu senze umsebenzi waso, kumelwe sikwazi ukubutha imisebe yokukhanya eminingi ngangokunokwenzeka entweni encane. Ukuze senze kanjalo, ilens yalokho okubhekwayo ilolongeke njengengxenye yendilinga, okuthile okunjengesigqoko sekhowe. Nakuba inobubanzi obiyimilimitha kuphela noma ngaphansi, ubuso bayo kumelwe bukwazi ukuthatha into eyingxenye eyodwa kweziyinkulungwane zemilimitha.
Ngokuthakazelisayo, ukukwazi ukubona izinto ezincane akuxhomekanga kakhulu kulelithuluzi kunasekukhanyeni okusetshenziselwa ukukhanyisa leyonto. Lapho into ebukwayo incane, kulapho ubude bamaza okukhanya okukhanyisayo kumelwe abe mancane khona ngokwengeziwe. Izibona-khulu zokubona zisebenzisa ukukhanya okubonakalayo, futhi lokhu kuzenza zingakwazi ukubona izinto ezingaphansi kwengxenye eyodwa yezinkulungwane eziyishumi zemilimitha ububanzi. Izibona-khulu zakuqala zenza izazi zesayensi ukuba zithole ukuthi izitshalo ziqukethe amangqamuzana angenakubalwa—okwakuyisambulo. Namuhla, abafundi besayenzi yezinto eziphilayo bangahlola indawo yamabacterium namangqamuzana egazi ngezibona-khulu zasekilasini.
Ukuze sibone izinto ezincane nangokwengenziwe, sinesibona-khulu esisebenza ngama-electron. Njengoba lelogama libonisa, esikhundleni sokukhanya okubonakalayo, imisebe yamaelectron anesivinini esiphakeme aqondiswa ezintweni ezincane ezifinyelela ezingxenyeni eziyisigidi zemilimitha. Lokhu kwenza amavirus nezilongotshana ezinkudlwana kubonakale.
Kuthiwani ngokwakheka kweathomu noma umnyombo wayo? Ukuze zikwazi ukubona lezizinto, izazi zesayensi kudingeka “zihlahlele” iathomu bese zisebenzisa amacomputer ukuze zakhe umfanekiso womphumela. Ngakho, ngomqondo othile, “izibona-khulu” ezinkulu nezinamandla kakhulu ziyimishini esheshisa ijubane lezilongosha—amacyclotron, amasynchrotron, nokunye—ubukhulu bezinye bulinganiswa ngamakhilomitha. Lamathuluzi aye enza izazi zesayensi zakwazi ukubona izimfihlakalo zamandla ahlanganisa indawo yonke.
Isimangaliso Sokubona
Omunye angase acabange ukuthi, uma liqhathaniswa nalamathuluzi ayinkimbinkimbi, iso lomuntu belingaba isidala ngempela. Kungenzeka aliyona inkimbinkimbi; kodwa alisona neze isidala! Iso alinankinga ngokuhlukahluka kwemibala yokukhanya. Isimiso salo sokubona ngokucacile esizenzakalelayo siyashesha futhi siyaphumelela. Lingabona emazingeni amathathu. Lingakwazi ukubona izigidi zamazinga ahlukahlukene okukhanya nemibala. Lingadala futhi ligcine umfanekiso omusha kuleyo naleyongxenye yeshumi yomzuzwana. Loluhlu lusalokhu luqhubeka. Yeka umsebenzi wobungcweti—iso lomuntu!
Yeka ukuthi sibonga kanjani ngokukwazi ukubona—ngezinto zokubona noma ngaphandle kwazo! Ulwazi olwandisiwe lwezinto ezinkulu nezincane, ezibonakalayo nezingabonakali, luye lwaletha izinzuzo eziningi eziphathekayo. Kodwa ngaphezu kwakho konke, isipho esimangalisayo sokubona, kanye nalokho okufundwayo ngesayensi yokubona, kufanele kusisize sibone ukuhlakanipha nothando lwalowo owalungiselela lezizinto, uMdali, uJehova uNkulunkulu.—IHubo 148; IzAga 20:12.
[Izithombe ekhasini 23]
IOrion nebula enhlekazi, eqhele ngama“light-year” angu-1 300
[Umthombo]
NASA photo
Isithombe esifakiwe: Esinye sezibona-kude eKit Peak National Observatory, eArizona, U.S.A.
[Izithombe ekhasini 24]
Ngenhla: Umfanekiso wophiko lwecimbi, okhuliswe ngesibona-khulu esisebenza ngama-“electron”
Ngezansi kwesobunxele: Lapho kukhuliswe izikhathi eziphindwe ka-40 000, kubonakala ngisho nemininingwane eyengeziwe, ebonisa umklamo oyinkimbinkimbi okhona ekwakhekeni kwazo zonke izinto eziphilayo.
[Umthombo]
Top and bottom left: Outdoor pictures
Ngezansi kwesokudla: Isibona-khulu sikaHooke esiyinkimbinkimbi esithathwe kwethi “Micrographia,” kaRobert Hooke, ngo-1665
[Umthombo]
Historical Pictures Service