Imvelaphi yangaphambilini Yomhlaba yachithwa

Ngo-2005, i-cosmochemist yaseWestern University U-Audrey Bouvier, ngosizo luka-Maud Boyet waseBlaise Pascal University, wathola ukuthi kukhona I-Neodymium-142 ( 142Nd; i-isotope yekhemikhali neodymium). Lokhu akutholakalanga ezintweni zasemhlabeni kuphela, kodwa nakwezinye izinto zeplanethi, ngokusetshenziswa kwe-thermal ionization mass spectrometry. 

Laba ababili bathole lokhu ngokuhlaziya ama-chondrites, i-meteorite efakwe ngamaminerali evame ukubizwa ngokuthi "izakhiwo zokwakha zomhlaba" phakathi komphakathi wesayensi. Ukuhlaziywa okuningiliziwe kwalezi zakhiwo ezinamatshe kuveze ukuthi imikhondo ye- 142Nd iyabonakala ngaphakathi kwalama meteorite. Ngokuphambene nenkolelo evamile yokuthi i-isotope yasungulwa emhlabeni, njengoba iplanethi ngokwayo yathuthukiswa ezigabeni zayo zokuqala. Ucwaningo olwengeziwe olwenziwa lusize ekukhanyiseleni iqiniso lokuthi i-neodymium yayibonakala nasezakhiweni ezingaphandle komhlaba, nakuba kuyizinhlobo ezahlukene ze-isotope. Ngakho, bafinyelela isiphetho ukuthi imvelaphi yoMhlaba ingase ihlotshaniswe ngokuseduze kakhulu neyamanye amaplanethi kunalokho umphakathi wesayensi owawucabanga ngakho. Ucwaningo olwengeziwe luyenziwa ukuze kuqinisekiswe ukufaneleka okwengeziwe kwalezi zimangalo.