Ukutholakala kwezingcezu zamatshe eziwela emhlabeni akujwayelekile
Amameteorite – okuyizingcezu zamatshe eziwele emhlabeni zisuka emkhathini kube yindaba ethakaselwa egudwini khona lapho kwaba nokwesaba. Kwabanye uma kuxoxwa ngalesi siga kufana nenganekwane kanti abanye bathi kuyizinkomba zokubuya kwendodana yomuntu njengoba behlale besho eBhayibhelini.
Emashumini eminyakeni eminingi edlule kuthiwa lokhu kwake kwenzeka njengoba sekuphinda futhi.
Amameteorite ahlukaniswa ngokufanelekile amazwe ngamazwe. Emazweni amaningi lokhu kuthathwa njengengxenye ebalulekile yamagugu emvelo yomphakathi.
INingizimu Afrika, lapho kwenziwa khona ucwaningo ngamameteorite, ingelinye lamazwe okuvamile ukuthi kwenzeke kuwo lezi zimanga. Ekupheleni kowe-2021, UMnu uGideon Lombaard, umlimi waseWestern Cape wathintana nabacwaningi esola ukuthi uthole izingcezu ezimbili zemeteorite. Uma kubonakala kuyiqiniso, lokhu kungaba okokuqala ukutholwa kwemeteorite eNingizimu Afrika eminyakeni engaphezu kwengama-40.
Ngemva kokuhlola izingcezu ezihlukahlukene, ososayensi bakwazi ukukhombisa ukuthi lezi zingcezu ezimbili, nakuba zitholakale ziqhelelene ngekhilomitha nje kuphela kepha, azihlobene – okungukuthi, kufanele ngabe zivela ezenzakalweni ezihlukene zemeteor.
NgoNcwaba, ikomidi le-Meteoritical Society, elilawula zonke izethulo ezintsha zemeteorite, lasamukela ngokusemthethweni isiphakamiso sokuthi lezi zingcezu ezimbili zazingamameteorite ahlukene. Amagama abacwaningi abe esephakanyiswa kuBrierskop neWolfkop – ngemva kwezimpawu zendawo eduze nezingosi zabo zokutholwa.
Ukutholakala kwalokho okwaqhamuka noMnu uLombaard kwenyusa izibalo zaseNingizimu Afrika zamameteorite aqinisekisiwe zafinyelela ku-51 – okuyizinga eliphezulu kakhulu e-sub-Saharan Africa. INamibia inamameteorite aqinisekisiwe angu-18, iBotswana 12, Zimbabwe 4, kanye neLesotho ne-eSwatini eyodwa. Kodwa, uma kuqhathaniswa namameteorite angaphezu kuka-14,000 atholakala ogwadule lwaseSahara, inani lamameteorite aseningizimu ne-Afrika atholakele lincane kakhulu. Uhlelo oluhlangene lwezemfundo yemeteorite kanye nohlelo lokusesha lungathola izinzuzo ezinkulu.
Iyini imeteorite?
Imeteorite ucezu lwemfucumfucu yasemkhathini enamatshe esinda lapho ishayisana noMhlaba. Amameteorite avame ukutholwa ngumuntu obona idwala elingajwayelekile ngenkathi ephuma ehamba (ebizwa ngokuthi “thola”). Kodwa-ke, cishe u-2% wamameteorite ahlukaniswa ngokuthi “ukuwa” ngoba alandwa ngemva kwemicimbi yemeteor fireball.
Umndeni wamameteorite wakha izinhlobo eziningana zamatshe. Ingxenye encane kakhulu yamameteorite angaba ngu-72,000 atholakale emhlabeni wonke kuze kube manje ayizingcezu eziqhunyiswe phezulu enyangeni naseMars ngenxa yemithelela emikhulu. Iningi elimangalisayo libonakala livela ebhandeni le-asteroid eliphakathi kwemizila yeMars neJupiter. Ziyizingcezu ezisuka ekungqubuzaneni okudlule phakathi kwamanye alawa ma-asteroids akhishelwe emizileni egcine ngokuwela indlela yoMhlaba.
Isilinganiso samameteorite aphakathi kuka-10 no-50 alinganiselwa ukuthi afika emhlabeni nsuku zonke. Ubuchwepheshe buzosiza ekuthuthukiseni izinto ezintsha ezitholakele. Eminyakeni yamuva nje inani elandayo lamazwe afake amanethiwekhi amakhamera (afana neNASA’s CAMS) aklanyelwe ukurekhoda imikhondo yamameteor fireballs angakwazi ukuphinda aphindwe kathathu ukuze azame ukuthola indawo yokuwa. Amandla esayensi yesakhamuzi nawo ayasetshenziswa ezindaweni eziningi ngendlela yamavolontiya asesha amameteorite awile.
Icashunwe kwiThe Conversation ibhalwe nguSulwazi uRoger Lawrence Gibson