Umhlaba (i-astronomy)

Umhlaba sisijikelezi-langa sesithathu ukusuka eLangeni kwaye kuphela kwento yeenkwenkwezi eyaziwayo ukuba inobomi. Oku kwenziwa ukuba uMhlaba ube lihlabathi lolwandle, ekuphela kwalo kwiSolar System egcina amanzi angaphezulu kwamanzi. Phantse onke amanzi oMhlaba aqulethwe kulwandlekazi lwawo lwehlabathi, agubungela i-70.8% yoqweqwe loMhlaba. I-29.2% eseleyo yoqweqwe loMhlaba ngumhlaba, uninzi lwayo olukwimo yelizwekazi lelizwekazi ngaphakathi kumhlaba womhlaba. Ubuninzi bomhlaba womhlaba ubuncinci bufumile kwaye bugqunywe luhlaza, ngelixa amashiti amakhulu omkhenkce kwintlango yePolar yoMhlaba egcina amanzi amaninzi kunamanzi aphantsi komhlaba, amachibi, imilambo kunye namanzi omoya edibene. Uqweqwe loMhlaba luqulathe iitectonic plates ezihamba kancinane, ezidibanayo ukuze zivelise udederhu lweentaba, iintaba-mlilo neenyikima. Umhlaba unombindi ongaphandle wolwelo ovelisa imagnetosphere ekwaziyo ukuphambukisa uninzi lwemimoya etshabalalisayo yelanga kunye nemitha ye-cosmic.