M'zaka zapitazi za 500 miliyoni, pakhala pali magawo asanu a kutha kwakukulu zamoyo pa Dziko Lapansi pamene zoposa zitatu mwa zinayi za zamoyo zomwe zinalipo zinathetsedwa. Kutha komaliza kwa moyo waukulu wotere kunachitika chifukwa cha kukhudzidwa kwa asteroid pafupifupi zaka 65 miliyoni zapitazo mu nthawi ya Cretaceous. Zotsatira zake zidapangitsa kuti ma dinosaurs achotsedwe pamaso pa Earth.
Zinthu za Near-Earth (NEOs) monga asteroids ndi comets, mwachitsanzo, zinthu zomwe zimadutsa pafupi ndi dziko lapansi. orbit zili zowopsa. Chitetezo cha mapulaneti ndizokhudza kuzindikira ndi kuchepetsa ziwopsezo zakukhudzidwa ndi ma NEO. Kupatutsa asteroid kutali ndi Dziko Lapansi ndi njira imodzi yochitira izi.
Mayeso a Double Asteroid Redirection Test (DART) inali ntchito yoyamba yosintha kayendedwe ka asteroid mu danga kupyolera mu mphamvu ya kinetic. Chinali chiwonetsero chaukadaulo wa kinetic impactor viz., kukhudza asteroid kuti isinthe liwiro ndi njira yake.
Cholinga cha DART chinali njira ya binary asteroid yomwe ili ndi asteroid yayikulu Didymos ndi asteroid yaying'ono, Dimorphos yomwe. mayendedwe wamkulu wa asteroid. Zinali zoyenera kwa oyamba chitetezo cha dziko kuyesa, ngakhale sikuli panjira yogundana ndi Dziko lapansi ndipo sikuyambitsa vuto lililonse.
Chombo cha DART chinakhudza Dimorphos ya asteroid pa 26 September 2022. Zinawonetsa kuti kinetic impactor ikhoza kupatutsa asteroid yowopsa ikagundana ndi Earth.
Kafukufuku yemwe adasindikizidwa pa Marichi 19, 2024 akuti zasintha zonsezi orbit ndi mawonekedwe a Dimorphos. Njirayi sikhala yozungulira, ndipo nthawi ya orbital ndi mphindi 33 ndi masekondi 15 kufupi. Maonekedwe ake asintha kuchoka ku "oblate spheroid" wofanana kukhala "triaxial ellipsoid" ngati chivwende cha oblong.
Gulu lofufuzalo linagwiritsa ntchito magwero atatu a data pamakompyuta awo kuti adziwe zomwe zimachitika pamlengalenga.
- Zithunzi zojambulidwa ndi chombo cha m'mlengalenga cha DART: Zithunzi zojambulidwa ndi chombocho chikuyandikira mlengalenga ndikuzibweza ku Earth kudzera. NASA's Deep Space Network (DSN). Zithunzizi zidapereka miyeso yapafupi ya kusiyana pakati pa Didymos ndi Dimorphos ndikuwunikanso kukula kwa ma asteroids onse asanachitike.
- Zowonera radar: DSN's Goldstone Solar System Radar idagunda wailesi mafunde amachotsa ma asteroids onse kuti ayeze bwino malo ndi liwiro la Dimorphos poyerekeza ndi Didymos pambuyo pa kugunda.
- Chidziŵitso chachitatu chinaperekedwa ndi makina oonera zakuthambo padziko lonse amene anayeza “kupindika kwa kuwala” kwa ma asteroid, kapenanso mmene kuwala kwa dzuŵa kumasinthira m’kupita kwa nthaŵi. Poyerekeza zokhotakhota zowunikira zisanachitike komanso pambuyo pake, ofufuzawo amatha kuphunzira momwe DART idasinthira kuyenda kwa Dimorphos.
Pamene Dimorphos imazungulira, nthawi ndi nthawi imadutsa kutsogolo ndi kumbuyo kwa Didymos. M'zinthu zomwe zimatchedwa "zochitika zofanana," asteroid imodzi imatha kuyika mthunzi pa inzake, kapena kutilepheretsa kuona dziko lapansi. Mulimonse momwe zingakhalire, dimming kwakanthawi - kuviika munjira yowala - idzajambulidwa ndi telescopes.
Gulu lofufuzalo linagwiritsa ntchito nthawi ya mndandanda wolondola wa ma curve dips kuti azindikire mawonekedwe a kanjira ndikuzindikira mawonekedwe a asteroid. Gululo lidapeza njira ya Dimorphos tsopano ndiyotalikirapo pang'ono, kapena eccentric.
Ofufuzawo adawerengeranso momwe Dimorphos 'orbital period idasinthira. Atangokhudzidwa, DART inachepetsa mtunda wapakati pakati pa ma asteroid awiriwa, kufupikitsa nthawi ya Dimorphos ya orbital ndi mphindi 32 ndi masekondi 42, mpaka maola 11, mphindi 22, ndi masekondi 37. M'masabata otsatirawa, nthawi ya orbital ya asteroid idapitilira kufupikitsidwa pomwe Dimorphos idataya miyala yambiri. danga, potsiriza kukhazikika pa maola a 11, maminiti a 22, ndi masekondi a 3 pa orbit - mphindi 33 ndi masekondi 15 nthawi yochepa kusiyana ndi zomwe zisanachitike.
Dimorphos tsopano ili ndi mtunda wocheperako kuchokera ku Didymos pafupifupi 3,780 mapazi (1,152 metres) - pafupifupi 120 mapazi (37 metres) kuyandikira kuposa momwe zimakhudzira kale.
Ntchito yomwe ikubwera ya Hera (yomwe idzakhazikitsidwe mu 2024) ya ESA idzapita ku binary asteroid system kuti ikafufuze mwatsatanetsatane ndikutsimikizira momwe DART idasinthiranso Dimorphos.
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Zothandizira:
- NASA. Nkhani - Phunziro la NASA: Orbit ya Asteroid, Mawonekedwe Asinthidwa Pambuyo pa DART Impact. Yolembedwa pa Marichi 19, 2024. Ipezeka pa https://www.jpl.nasa.gov/news/nasa-study-asteroids-orbit-shape-changed-after-dart-impact
- Naidu SP, Et al 2024. Makhalidwe a Orbital ndi Physical of Asteroid Dimorphos Kutsatira DART Impact. The Planetary Science Journal, Volume 5, Number 3. Lofalitsidwa 19 March 2024. DOI: https://doi.org/10.3847/PSJ/ad26e7
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