Ihlabathi yindawo eyiplanethi yesithathu ukusuka elangeni kwaye kukuphela kweplanethi eyaziwa njengenobomikuyo. Ihlabathi eli leenzeka kwisithuba sezigidigidi ezi4.5 billion zeminyaka eyadlulayo.[1] lelinye leeplanethi ezine ezinamatye ngaphakathi kwisolar izinto ezijikeleze ilanga. Ezinye zazo ziiMercury, iVenus, kunye neMars.

Ubunzima obukhulu mass belanga benza okokuba ihlabathi lilijikeleze ngokwesazinge, kanye oku kobunzima behlabathi xa busenza okokuba inyanga ilijikeleze . Nehlabathi ngokunjalo liyazijikikelezela, ngoko ke iindawo ngeendawo zijonge ngaselangeni ngamaxesha ahlukeneyo. Ihlabathi lijikeleza ilanga kanye (kube kanye ngo"year") qho kwisithuba esingangamawaka ama-365¼ lijikeleza oko (kanye ngo"suku").

Inyanga ijikeleza umhlaba qho kwiintsuku ezimalunga nama-27⅓, kwaye ibanokukhanya okuvela elangeni. Njengokuba ihlabathi lijikelelza ilanga kwangelo xesha linye, ukutshintsha kokukhanya kwenyanga kuthatha iintsuku ezimalunga nama-29½ ukuba itshintshe ebumnyameni iye ekukhanyeni okuqaqambileyo isuke apho iphindele ebumnyameni kwakhona. Kulapho ke kwavela khona lo mbono wenyanga. Kodwa ke ngoku iinyanga ezininzi zineentsuku ezingama-30 okanye ama-31 zitsho zikulungele ukwenza unyaka.

ihlabathi kukuphela kweplanethi kwinkqubo yethu yezinto ezijikeleza ilanga enobumanzi obuninzi naamanzi.[2] Malunga nama71% zomhlaba zogqunywe ngeelwandle. Ngenxa yesi sizathu, maxa wambi kuthiwa yiplanethi eluhlaza okwesibhakabhaka. iThemplethi:Refn

Ngenxa yamanzi ayo, ihlabathi lilikhaya lezigidi zeentlobo zeizityalo nezilwanyana.[3][4] Izinto eziphila emHlabeni ziyitshinsthe kwaphela umphezulu nembonakalo yomhlaba. umzekelo, early cyanobacteria changed the air and gave it I-oxygen. The living part of the Earth's surface is called the "biosphere".[5]

Igophe lokujika

tshintsha
 
Ihlabathi lijika kwigophe ekuthiwa yi"axial tilt") ngokunxulumene nomzila wayo ojikeleze langa

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Ihlabathi yinxalenye yeeplanethi ezisibhozo kwakunye nenxalenye yamawakawaka ezinto ezincinane ezizulazula zijikeleza ilanga njengenkqubo yokujikeleza kwezinto ezingqonge ilanga. Inkqubo yokujikeleza kwezinto ezingqonge ilanga ihamba ngeNgalo yeOrion yeMilky Way Galaxy ngoku, kwaye oku kuyakwenzeka isithuba seminyaka eli-10,000.[6]

Ihlabathi ngokubanzi iThemplethi:Liguqula kude le kwilanga (lo mgama ubizwa ngokuba yi"Astronomical Unit"). Umhlaba uhamba ngendlela yawo ngesantya esikumyinge wama 30 km or 19 mi ngomzuzwana. [7] Umhlaba ujika kuyo yonke le ndlela malunga ne-365¼ yamathuba athatyathwa lilanga ngelo xesha ke uMhlaba wona uchitha uyihamba yonke loo ndlela ujikeleza ilanga.[8] Ukuze kubekho usuku olude kunezinye qho ngonyaka, usuku olongezelelweyo lubakho qho kwiminyaka emine. kuthiwe ke lo nyaka yi"leap year".

Inyanga ijikeleza umHlaba kumgama ongumyinge we 400,000 kilometers (250,000 mi). It is locked to Earth, so that it always has the same half facing the Earth; the other half is called the "Dark Side of the Moon". It takes about 27⅓ days for the Moon to go all the way around the Earth but, because the Earth is moving around the Sun at the same time, it takes about 29½ days for the Moon to go from dark to bright to dark again. This is where the word "month" came from, even though most months now have 30 or 31 days

Imithombo

tshintsha
  1. iThemplethi:Citeweb
  2. iThemplethi:Citeweb
  3. iThemplethi:Citeweb
  4. Purves, William Kirkwood et al (2001) Life, the science of biology Macmillan p. 455 ISBN 0716738732 
  5. iThemplethi:Citeweb
  6. iThemplethi:Citeweb
  7. iThemplethi:Citeweb
  8. Staff (2007-08-07) "Useful Constants" International Earth Rotation and Reference Systems Service retrieved 2008-09-23