Ukuvakashelwa Kweplanethi Ebomvu Futhi

“Abaseshi” ababili abasuka eMhlabeni bathunyelwe kumakhelwane wethu esimisweni sikanozungezilanga, i-Mars. Abazokuthola kungase kusize ekuphenduleni imibuzo ethile eyisisekelo ngokuphathelene nomlando wale planethi ebomvu kanye nesimo sayo samanje.

KUSUKELA endulo, i-Mars ibilokhu ishukumisa izingqondo zabantu. Okhokho bethu babenomuzwa wokuthi kukhona okuyinqaba ngale ndikimba yasemkhathini egqamile, ebomvu, eyayitshuza emkhathini iyodwa ishiye ezinye izinkanyezi. AbaseBabiloni lasendulo, amaGreki namaRoma betha le planethi ngonkulunkulu babo bempi nokufa, bengaliqapheli iqiniso lokuthi umbala wayo obomvu wawumane ubonisa ukuthi inhlabathi yayo ine-iron oxide.

Ezikhathini zamuva nje, njengoba izazi zezinkanyezi zisebenzisa izibona-kude ezinamandla ukuze zihlole isimiso sonozungezilanga, ziqaphela ukuthi lo makhelwane wethu obomvu unezinkathi zonyaka, iqhwa eningizimu nasenyakatho, kanye nezinye izici ezifana nalezo ezitholakala eMhlabeni. Ekhulwini lama-20, i-Mars yaqale yahlolwa ngemikhumbi-mkhathi eminingi, kuhlanganise naleyo ezungeza emkhathini kanye nehlala phansi kuyiplanethi, eyathunyelwa yiSoviet Union ne-United States. Kwabe sekulandela uhambo lwe-Mars Pathfinder, olwakhanga izigidigidi zababukeli bethelevishini ngo-July 1997.a

Okwamanje, umkhumbi-mkhathi i-Mars Global Surveyor uqongelela ukwaziswa ngale planethi ebomvu. Nakuba lolu hambo luye lwembula ukwaziswa okuningi, kusaphakama imibuzo eminingi eyisisekelo ngokuphathelene ne-Mars.

Akuphi Amanzi?

Isici esivelele kule mibuzo yindaba yamanzi. Ososayensi bacabanga ukuthi endulo, i-Mars yayihluke kakhulu kulokho eyikho namuhla. Bachaza ukuthi le planethi yayinesimo sezulu esithokomele, umoya onomhwamuko, nemifula egelezayo eyayimatisa izwe. Nokho, la manzi anyamalala ngandlela-thile, ashiya imbulunga eyomile, enothuli nemimoya evunguzayo ewugwadule ngempela uma uyiqhathanisa nezingwadule zoMhlaba. Ashonaphi lawo manzi? Amanzi angatholakala kuphi manje kuyi-Mars, futhi akusiphi isimo? Amanzi asithonya kanjani isimo sezulu se-Mars?

UNorman Haynes, owayephethe ihhovisi le-Mars Exploration leJet Propulsion Laboratory ye-NASA, ePasadena, eCalifornia, uthi: “Kudingeka ukuphenyisisa. Inselele enkulu nge-Mars ukuthola ukuthi kwenzekani ngalawo manzi.” Ososayensi banethemba lokuthi maduze bazoyithola impendulo. Cishe njalo ngemva kweminyaka emibili, lapho uMhlaba uqondene ne-Mars, abacwaningi bahlela ukuthumela imishini yamarobothi ukuba iyoxazulula le mfihlakalo ye-Mars.

Iqembu lamuva nje lalabo “baseshi,” umkhumbi-mkhathi ohlola isimo sezulu kanye nerobothi elithatha amasampula elizonikeza ososayensi umbono ongcono wokuthi kunani ngaphansi kwenhlabathi ye-Mars. Amagama alaba baseshi ngo-Mars Climate Orbiter no-Mars Polar Lander.

Ukuhlola Indawo Phezulu

I-Mars Climate Orbiter yacitshwa emkhathini ngo-December 11, 1998, eKennedy Space Center, eCape Canaveral, eFlorida, futhi yaqala uhambo lwayo lwezinyanga ezingu-9 lokuya kuyi-Mars. Iklanyelwe ukuba izungeze ebangeni eliphakeme ngamakhilomitha angu-400, lapho iyokwazi khona ukuhlola isimo sezulu sale planethi, izici ezikuyo kanye nezintaba zeqhwa ezisenyakatho naseningizimu. Ucwaningo luyothatha wonke unyaka wakuyi-Mars—okuwukuthi, isikhathi esiyizinsuku ezingu-687 lapha eMhlabeni.

Umsebenzi walo mkhumbi-mkhathi uhlanganisa ukuhlola ukubukeka nokuvunguza kothuli kanye nomhwamuko kuyi-Mars. Futhi uklanyelwe ukuba uhlole ukushintsha kwezinkathi zonyaka kule planethi. Izithombe ezicacile zezici zendawo zingase zinikeze ososayensi umkhondo ngokuphathelene nokuthi sasinjani isimo sezulu sale planethi endulo. Ngaphezu kwalokho, ukwaziswa okunjalo kungase kunikeze abacwaningi ukwaziswa okwengeziwe ngemithombo yamanzi okungenzeka ikhona ngaphansi kwe-Mars.

Lo mkhumbi-mkhathi uyosebenza futhi njengomxhumanisi womngane wawo, i-Mars Polar Lander. Lona wamuva wacitshwa ngo-January 3, 1999, futhi kulindeleke ukuba ufike kuyi-Mars ekuqaleni kuka-December nonyaka. Kodwa lo mkhumbi-mkhathi uyohlala kuphi ukuze uveze imiphumela engcono kakhulu?

Uyohlala Kuphi?

Khumbula ukuthi indaba yamanzi iyisici esibaluleke kakhulu ekuhlolweni kwe-Mars. Ikuphi indawo ekahle kuleyo planethi yokuhlola amanzi? Isimo sezulu nomjikelezo wamanzi eMhlabeni kuhlolwa ngokuqhathanisa imiphumela yocwaningo olwenziwe ngamathuluzi ahlukahlukene ezindaweni ezahlukene. Nokho, ukuhlolwa kwamanye amaplanethi kudinga inqubo ekhethekile. Ngenxa yokuthi ithuba ngalinye lokuhlola inhlabathi kuyi-Mars liyivelakancane, abacwaningi besayensi kumelwe bacophelele lapho benquma ukuthi yimaphi amathuluzi abazowasebenzisa nokuthi bazowathumelaphi.

Kungcono ukuhlola isimo sezulu se-Mars ezindaweni ezisenyakatho naseningizimu—nakuba zihluke kakhulu emathafeni agcwele amadwala nemisele yamanzi lapho i-Mars Pathfinder yahlala khona eminyakeni emibili edlule. Kukulezi zindawo lapho ukushintsha kwezinkathi zonyaka kubonakala khona ngokucacile. Kucatshangwa ukuthi iziphepho zothuli eziba khona lapho kushintsha izinkathi zonyaka zishiya uthuli enyakatho naseningizimu. Lapho kufika ubusika, lolu thuli lumbozwa yiqhwa lesikhutha namanzi. Njengoba kuhamba isikhathi, kuye kwakheka izingqimba eziningi. “Lezi zingqimba zilondolozé umlando wesimo sezulu [se-Mars],” kusho uRalph Lorenz, e-University of Arizona. Ochwepheshe bakholelwa ukuthi ukuhlola le ndawo entsha kuyoba neqhaza elikhulu ekucwaningeni nge-Mars. Kanjani? Lo mkhumbi-mkhathi uyokwenzani lapho usufike khona?

Ukuhlola Ngaphansi Komhlabathi

Njengoba uwumshini ofana nesicabucabu, ongaba yimitha ukuphakama, lo mkhumbi-mkhathi unemilenze emithathu kanye nengalo engaba amamitha amabili ubude enokhezo ekugcineni. Umsebenzi wawo uyoqala ngaphambi kokuba uthi cababa kuyi-Mars. Ngaphambi nje kokungena emkhathini wale planethi ebomvu, lo mkhumbi-mkhathi uyokhipha amabhola amabili, ngalinye elilingana ne-basketball.

La mabhola amabili ayokwehla aze ayoshaya phansi ngesivinini esingamakhilomitha angu-700 ngehora. Aklanywe ngendlela yokuba aphahlazeke lapho eshaya phansi, kuphume imishini emibili emincane eyoshona phansi ibanga elingaba yimitha. Lapho isingaphansi komhlaba, le mishini iyokhipha amabhola amancane bese iqala ukuhlola ukuthi yimaphi amakhemikhali atholakala enhlabathini kuyi-Mars. Umgomo wokuqala kuyoba ukuthola ukuthi awekho yini amanzi ayiqhwa ngaphansi komhlabathi.

Ngokushesha ngemva kokuba le mishini isifike enhlabathini, kuyobe sekulandela umkhumbi-mkhathi, oyokwehliswa nge-parachute. Njengoba uhlome ngamakhamera nemishini yokuthungatha amaza, lo mkhumbi-mkhathi uklanyelwe ukuhlola indawo nesimo sezulu kuyi-Mars. Uyothwebula izithombe lapho wehla nalapho usuthé cababa phansi. Umbhobho ofakwe kuwo uyoqopha umsindo womoya kuyi-Mars ngokokuqala ngqá. Kuhlelwe ukuba lo mkhumbi-mkhathi usebenze izinsuku ezingaba ngu-90 ngemva kokuhlala phansi.

Isifiso Sokuhlola

Yiqiniso, kuyobathatha iminyaka eminingi ososayensi ukucwaninga nokuhlaziya ukwaziswa okuqongelelwe yi-Mars Climate Orbiter ne-Mars Polar Lander. Le mikhumbi-mkhathi ecitshwe muva nje iyingxenye yomzamo weminyaka engu-16 wokufunda okwengeziwe nge-Mars. Ngaphandle kwe-NASA, izinhlangano ezihlola umkhathi zaseJapane, eRussia naseYurophu nazo zihilelekile kuleyo mikhankaso. Ekugcineni, ososayensi bathemba ukuthi ohambweni lwesikhathi esizayo kuyotholakala amasampula enhlabathi ye-Mars azohlolwa ezikhungweni zocwaningo ezilapha eMhlabeni. Lokhu ekugcineni kungase kubasize ukuba baphendule umbuzo wokuthi kwenzekani ngesimo sezulu seplanethi ebomvu engumakhelwane wethu, i-Mars.

[Umbhalo waphansi]

[Ibhokisi/Isithombe ekhasini 15]

Ingabe Ukuphila Kwavela Kuyi-Mars?

I-meteorite ALH84001—okukholelwa ukuthi yavela kuyi-Mars—yatholakala e-Antarctica ngo-1984. Ngo-August 1996 abanye abacwaningi baseJohnson Space Center ye-NASA naseStanford University bamemezela ukuthi leli tshe elingangezambane liqukethe ubufakazi obungacacile ngokuphelele bokuthi kunokuphila kuyi-Mars—izinsalela, amaminerali nezilwanyana ezincane. Lokhu kwakusho ukuthi ukuphila eMhlabeni kungenzeka kwaqala kuyi-Mars.

Nokho, cishe bonke ososayensi bayavumelana ngokuthi le meteorite ayinakuba ubufakazi obuqinisekile bokuthi ukuphila kwaqala kuyi-Mars. UWilliam Schopf wase-University of California, eLos Angeles, wathi: “Ngicabanga ukuthi akunakwenzeka ukuthi kunezinsalela zokuthile okuphilayo.” Ngokufanayo, uRalph P. Harvey waseCase Western Reserve University, wathi: “Nakuba abaningi bethu becabanga ukuthi kunokuthile okuphilayo kuyi-Mars, kusobala ukuthi i-ALH[84001] ayinabo ubufakazi balokho.”b

[Umbhalo waphansi]

[Ibhokisi/Izithombe ekhasini 16, 17]

Iminyaka Engamashumi Amane Yokuhlolwa Kwe-Mars

◼ Ngo-1960 elaseSoviet Union laciba imishini emibili yokuhlola amaplanethi, eyathunyelwa kuyi-Mars. Le mishini ayizange ifinyelele emkhathini.

◼ Ngo-July 14, 1965, i-Mariner 4 yase-United States, yadlula kuyi-Mars futhi yathumela eMhlabeni izithombe nezilinganiso zobukhulu beplanethi.

◼ Ngo-1971, i-Mars 3, umshini wasemkhathini waseSoviet, waciba inqola yokuqala eyayizihambela yodwa eyahlala kuyi-Mars. I-Mariner 9, umshini wasemkhathini wase-United States, yafika kuyi-Mars ngawo lowo nyaka futhi yathwebula izithombe zengxenye enkulu yaleyo planethi. I-Mariner 9 nayo yathwebula izithombe eziveza izinyanga ezimbili ezincane zale planethi, i-Phobos ne-Deimos.

◼ Imishini yasemkhathini emibili yase-Unites States, i-Viking 1 ne-Viking 2, zahlala kuyi-Mars ngo-1976. Le mishini yasebenza iminyaka eminingi, yenza ucwaningo oluyinkimbinkimbi.

◼ Ngo-1988, ososayensi baseSoviet baciba imikhumbi-mkhathi emibili, i-Phobos 1 ne-Phobos 2, eya kuyi-Mars. I-Phobos 1 yehluleka ukundiza, kodwa i-Phobos 2 yafika kuyi-Mars futhi kwaphela izinsuku ezimbalwa ithumela imiphumela yocwa- ningo emhlabeni.

◼ Ngo-1992 elase-United States laciba umshini wasemkhathini i-Mars Observer, owahluleka ukufeza umsebenzi wawo.

◼ I-Mars Pathfinder, eyayithwele irobothi i-Sojourner, yafika kuyi-Mars ngo-July 4, 1997. Kwatholakala izithombe ezinhle ezigqamile zomhlabathi wale planethi ebomvu.

[Izithombe]

I-Mariner 4

Omunye wemishini ye-Viking

I-Phobos 2

[Isithombe ekhasini 15]

I-Mars Climate Orbiter

[Isithombe ekhasini 15]

I-Mars Polar Lander

[Isithombe ekhasini 16, 17]

Isithombe se-Mars, esithwetshulwe yi-Mars Pathfinder

[Imithombo Yesithombe ekhasini 14]

Page 15: Meteorite: NASA photo; background: NASA/U.S. Geological Survey; orbiter and lander: NASA/JPL/Caltech

Pages 16 and 17: Landscape, Mariner 4, Viking lander: NASA/JPL/Caltech; planet: NASA photo; Phobos 2: NASA/National Space Science Data Center