Kwiminyaka ezigidi ezingama-500 edlulileyo, kuye kwakho iziqendu ezintlanu ubuncinane ukuphelelwa ngamandla yezidalwa eziphilayo emhlabeni xa ngaphezulu kwekota ezintathu zeentlobo ezikhoyo zapheliswa. Ukuphela kobomi bokugqibela kubukhulu becala kwenzeka ngenxa yempembelelo ye-asteroid malunga ne-65 yezigidi zeminyaka eyadlulayo kwixesha le-Cretaceous. Iimeko zesiphumo zakhokelela ekuphelisweni kweedinosaurs ebusweni be umhlaba.
Izinto ezikufuphi noMhlaba (NEOs) ezifana ne-asteroids kunye ne-comets, oko kukuthi, izinto ezidlula kufutshane nomhlaba. ukuhamba zinokuba yingozi. Ukhuselo lweplanethi imalunga nokufumanisa kunye nokunciphisa izoyikiso zempembelelo ezivela kwiiNEOs. Ukuphambukisa i-asteroid kude noMhlaba yenye yeendlela yokwenza oku.
UVavanyo lwe-Asteroid Redirection eDouble (DART) yayiyimishini yokuqala ezinikele ekutshintsheni intshukumo ye-asteroid isithuba ngempembelelo kinetic. Ibilumboniso wetekhnoloji ye-kinetic impactor viz., echaphazela i-asteroid ukulungisa isantya kunye nendlela yayo.
Ithagethi ye-DART yayiyinkqubo yokubini yeasteroid equka i-asteroid enkulu i-Didymos kunye ne-asteroid encinci, i-Dimorphos ethi ii-orbits iasteroid enkulu. Yayingumgqatswa ofanelekileyo kuqala ukhuselo lweplanethi ulingelo, nangona ingekho kwindlela yokungqubana noMhlaba kwaye ayibangeli isoyikiso sokwenyani.
Isiphekepheke se-DART sibe nefuthe kwi-asteroid Dimorphos ngomhla wama-26 kuSeptemba 2022. Ibonise ukuba impembelelo yekinetic ingaphambukisa iasteroid eyingozi kwindlela yokungqubana noMhlaba.
Uphononongo olupapashwe nge-19 kaMatshi ngo-2024 lunika ingxelo yokuba impembelelo yatshintsha zombini ukuhamba kunye nokumila kweDimorphos. I-orbit ayisekho setyhula, kwaye ixesha le-orbital yimizuzu engama-33 kunye nemizuzwana ye-15 emfutshane. Ubume butshintshile ukusuka kwi-symmetrical "oblate spheroid" ukuya kwi "triaxial ellipsoid" njengevatala ene-oblong.
Iqela lophando lisebenzise imithombo emithathu yedatha kwiimodeli zabo zekhompyuter ukufumana iziphumo zempembelelo kwi-asteroid.
- Imifanekiso ethathwe sisiphekepheke se-DART: Imifanekiso ethathwe sisiphekepheke njengoko isondela kwi-asteroid kwaye iyibuyisele eMhlabeni nge INethiwekhi yeNdawo eNzulu yeNASA (DSN). Le mifanekiso ibonelele ngemilinganiselo esondeleyo yomsantsa phakathi kweDidymos kunye neDimorphos ngelixa ikwalinganisa imilinganiselo yazo zombini iiasteroids ngaphambi nje kwempembelelo.
- Ukuqwalaselwa kweRadar: I-DSN ye-Goldstone Solar System Radar iqhume unomathotholo amaza asuka kuzo zombini iiasteroids ukulinganisa ngokuchanekileyo indawo kunye nesantya seDimorphos ngokunxulumene neDidymos emva kwempembelelo.
- Umthombo wesithathu wolwazi wanikelwa ziiteleskopu zomhlaba ezijikeleze ihlabathi ezilinganisa zombini “ijika elijikajikayo” leeasteroids, okanye indlela ukukhanya kwelanga okubonakala kwimigangatho yeeasteroids eyatshintsha ngayo ekuhambeni kwexesha. Ngokuthelekisa iijika zokukhanya ngaphambi nangemva kwempembelelo, abaphandi banokufunda indlela i-DART eguqule ngayo intshukumo yeDimorphos.
Njengoko i-Dimorphos ijikeleza, idlula rhoqo ngaphambi nangemva kwe-Didymos. Kwezi zinto zibizwa ngokuba “ziziganeko ezifanayo,” enye iasteroid inokuphosa isithunzi kwelinye, okanye ithintele umbono wethu eMhlabeni. Kuyo nayiphi na imeko, ukufiphala okwethutyana - ukudipha kwijika elikhanyayo - kuya kubhalwa ngeeteleskopu.
Iqela lophando lisebenzise ixesha lolu luhlu oluchanekileyo lwe-light-curve dips ukufumanisa imilo ye-orbit kwaye yafumanisa imilo ye-asteroid. Iqela lifumene i-orbit ye-Dimorphos ngoku yande kancinci, okanye i-eccentric.
Abaphandi baphinde babala indlela i-Dimorphos 'orbital period yavela ngayo. Ngokukhawuleza emva kwempembelelo, i-DART yanciphisa umgama ophakathi phakathi kwee-asteroids ezimbini, inciphisa ixesha le-orbital ye-Dimorphos ngemizuzu ye-32 kunye ne-42 imizuzwana, ukuya kwiiyure ze-11, imizuzu ye-22 kunye ne-37 imizuzwana. Kwiiveki ezilandelayo, ixesha lokujikeleza kwe-asteroid laqhubeka lifinyela njengoko i-Dimorphos ilahlekelwa yizinto ezinamatye. isithuba, ekugqibeleni ukuhlalisa kwiiyure ze-11, imizuzu ye-22, kunye ne-3 imizuzwana nge-orbit - imizuzu ye-33 kunye ne-15 imizuzwana yexesha elingaphantsi kuneempembelelo zangaphambili.
I-Dimorphos ngoku inomgama oqhelekileyo we-orbital ukusuka kwi-Didymos malunga ne-3,780 yeenyawo (i-1,152 yeemitha) - malunga ne-120 yeemitha (i-37 yeemitha) kufutshane kunangaphambili impembelelo.
I-mission ye-Hera ezayo (eya kuqaliswa kwi-2024) ye-ESA iya kuhamba kwi-binary asteroid system ukwenza uphando olunzulu kwaye iqinisekise indlela i-DART eguqule ngayo i-Dimorphos.
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Iingxelo:
- NASA. Iindaba - Uphononongo lweNASA: I-Asteroid's Orbit, iMilo eTshintshwe emva kweMpembelelo ye-DART. Ithunyelwe nge-19 kaMatshi 2024. Iyafumaneka e https://www.jpl.nasa.gov/news/nasa-study-asteroids-orbit-shape-changed-after-dart-impact
- Naidu SP, okqhubekayo 2024. I-Orbital kunye ne-Physical Characterization ye-Asteroid Dimorphos Ukulandela i-DART Impact. I-Planetary Science Journal, uMqulu 5, iNombolo yesi-3. Ipapashwe nge-19 kaMatshi ngo-2024. DOI: https://doi.org/10.3847/PSJ/ad26e7
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