Iyunifomu enkulu ye-aurora ebonwe emhlabeni ngobusuku beKrisimesi ka-2022 iqinisekisiwe ukuba yimvula yepolar aurora. Esi yaba sisiganeko sokuqala esisekwe emhlabeni kwi-polar rain aurora. Ngokungafaniyo ne-aurora eqhelekileyo eqhutywa zii-electron zesiganeko ezigcinwe kwimagnetotail yemagnetosphere yomhlaba, i-polar rain aurora yenziwa zii-electron ezihamba ngokuthe ngqo ukusuka kwi-corona yelanga ukuya kwi-polar kwimimandla yomhlaba ecaleni kwemigca yemagnethi evulekileyo ukuya kutsho kuvuthondaba “kwipolar. imvula” imvula ye-electron ebangela ukuba kubekho izinto ezikhutshwayo zamehlo xa idibana neoksijini kunye neeathom zenitrogen emoyeni.
Ibali le-aurorae, ukukhanya okuqaqambileyo okumibalabala kubonisa (okubizwa ngokuba zizibane zaseMantla okanye i-aurora borealis kwingingqi esemantla kunye nezibane zaseMazantsi okanye i-Aurora Australis kwingingqi esemazantsi) iqala kumaleko e-coronal emoyeni welanga. Ubushushu balo maleko we-atmospheric yelanga buphezulu kakhulu. Ngelixa ubushushu be i-photosphere layer (ethathwa njengomphezulu welanga kuba le nto sinokuyibona ngokukhanya) malunga ne-6000 Kelvin, ubushushu obuphakathi kwe-corona buphakathi kwe-1 ukuya kwi-2 yesigidi se-Kelvin ngenxa ye-'Coronal Heating Paradox'. Ubushushu obuphezulu ngolo hlobo benza i-corona ibe ngumaleko weplasma eshushu kakhulu. Umoya welanga oquka amasuntswana asebenza ngamandla ombane (njengeelektroni, iiproton, amasuntswana e-alpha kunye neeyoni ezinzima) oqhubekayo uphuma kumaleko e-coronal kuwo onke amacala kuquka kwicala loMhlaba.
Uhambo lwangaphandle lwamasuntswana atshajisiweyo anamandla ukusuka elangeni ukuya emhlabeni alulula kwaye luthe ngqo. Ngokuqhelekileyo, amasuntswana e-ioned ajikwa yimagnethi yomhlaba (magnetosphere) ngoko ke iifom zobomi kunye neenkqubo zombane emhlabeni zihlala zingachaphazeleki kwiziphumo eziyingozi zomoya welanga.
Nangona kunjalo, kwimeko yokukhutshwa okukhulu kwamasuntswana ahlawulisiweyo ukusuka elangeni njengakwimeko ye-Coronal Mass Ejection (CMEs), imagnetosphere yomhlaba iyoyisakala kwaye iziphumo zesaqhwithi semagnethi. Isaqhwithi sigxininisa i-magnetosphere de ibuyele umva iphosa amanye amasuntswana ahlawuliweyo ukuya eMhlabeni.
Ibhendi yokuhlehla yamandla kazibuthe irhuqa ii-electron kumoya welanga ukuya kwimimandla epholileyo apho i-aurorae ibonwa i-100-300 km ngaphezu komphezulu kwi-atmosfera ephezulu. Igalelo leeproton kunye nezinye i-ion kumoya welanga ekubunjweni kwe-aurora ayinanto.
I-Aurora ngokusisiseko kukukhutshwa kwamehlo okuphuma kwioksijini kunye neeathom zenitrogen ezichulumanciswa zii-elektroni ezinamandla eziphuma kwimagnethi ehamba nemigca yomhlaba evaliweyo yemagnethi (imvula ye-electron yamandla okanye i-EEP ibhekiselele ekubekweni kwamandla eelektroni emoyeni). Ukusebenzisana kwee-elektroni ezinamandla kunye neoksijini emoyeni kunoxanduva lwemibala eluhlaza nebomvu ngelixa ukunxibelelana ne-nitrogen kukhokelela ekuvelisweni kwemibala eluhlaza kunye nebomvu enzulu.
Ke, ukubunjwa kwe-aurora kuqhutywa zii-electron zesiganeko ezigcinwe kwi-magnetotail (ummandla we-magnetosphere yomhlaba otshayelwa ngumoya welanga ukuya kumsila omkhulu kwicala elikude nelanga). Ii-elektroni ezigcinwe kwi-magnetosphere zifumana amandla kukunyanzeliswa komoya welanga kwaye emva koko zidlulele kwiatmosfera ngokugqabhuka kwemimandla yencam yomhlaba ukuze kubangele i-aurora.
Imvula yePolar Aurora
Nangona kunjalo, kunqabile, ii-aurorae zenziwa zii-electron ezihamba ngokuthe ngqo ukusuka kwi-corona yelanga ukuya kwimimandla yepolar yomhlaba kunye nemigca yemagnethi evulekileyo ukuze ifikelele incopho yemvula ye-electron "ye-polar". Imvula ye-electron enjalo ifunyenwe inamandla xa ubuninzi bomoya welanga buphantsi. Ukukhutshwa kwe-optical okubangelwa yi-electrons enjalo kubuthathaka kwaye i-aurora eyenziwe ibizwa ngokuba "yi-polar rain aurora".
I-aurorae yemvula encanyana iye yabonwa ngamaxesha ambalwa ukusuka emajukujukwini ziisathelayithi. Nangona kunjalo, akukho tyala elakhe lafunyanwa ngamaziko asezantsi.
Nge25th-26th NgoDisemba 2022, i-atypical aurora yabanjwa ziikhamera ezisekwe emhlabeni kwingingqi ye-Artic xa umoya welanga uphantse wanyamalala. I-aurora eyayijongwe yayifana kwaye inkulu ngobukhulu. Ayizange ibonakale njenge-aurora eqhelekileyo. Ipolar cap aurora eqhelekileyo ngumboniso wokukhanya oqaqambileyo obonisa iipateni eziguqukayo zezibane ezinjengomnyama. Isenokubonakala njengeekhethini, imitha, i-spirals, okanye njenge-flickers eguqukayo. Theta aurora ibonakala njengonobumba wesiGrike u-theta (i-oval enomgca onqumla embindini) xa ijongwa phezulu ziisathelayithi. I-Theta aurorae ikwabizwa ngokuba 'i-transpolar arcs' ngenxa yembonakalo yee-arcs ezinkulu xa zibonwa ukusuka phezulu. 'Ii-arcs ezihambelana nelanga.' zincinci kwaye zimfiliba ii-arcs ze-auroral ezijongwe kwiindawo zokujonga ezisekwe emhlabeni. Esinye isiphelo se-arcs sibhekiswe kwiLanga kungoko kuthiwa 'Ii-arcs ezihambelana nelanga. '
I-aurora eyabonwa ngobusuku beKrisimesi ngo-2022 yayigudileyo, isasazekile kwaye inkulu ngobukhulu. Yayingajongeki njenge-aurora eqhelekileyo kungoko kwakucingelwa ukuba yi-polar rain aurora. Ukuqinisekisa oku, abaphandi baphanda oku ngokusebenzisa idatha esekelwe kwisathelayithi kunye neyomhlaba.
Imifanekiso yesathelayithi ibonise ukuba indawo yepolar cap yayingenanto kwaphela ekuqaleni. I-polar cap yaqala ukuzaliswa yi-aurora epholileyo eyasasazeka nge-25th EtiMnga. Emva koko, phantse wonke ummandla okwincam encanyana ngokukhawuleza wagutyungelwa kukukhutshwa kwezinto ezikhutshwayo ezinamandla kodwa ezingalungelelananga kangako. Oku kuzaliswa kwe-polar cap nge-diffuse aurorae kuqhubeke malunga neeyure ezingama-28. Ukukhutshwa okumandla ngaphakathi komnqwazi wepolar kuqale ukuncipha ngentsasa yama-26th NgoDisemba kwaye kwiiyure ezimbalwa, isakhiwo se-aurora sasibuyele kulwabiwo oluqhelekileyo kwaye i-polar cap yayingenanto kwakhona.
Imvula ye-electron yemvula yepolar ngokuqhelekileyo iyenzeka kwi-hemisphere enye kuphela ngokuxhomekeke kwi-interplanetary magnetic field (IMF). Imifanekiso yesathelayithi ngexesha elinye ibonise ukuzaliswa okupheleleyo kwe-polar cap kwi-Northern Hemisphere ngelixa i-polar cap ye-Southern Hemisphere yayingenanto. Oku kuqwalaselwe i-asymmetry ye-interhemispheric kunye ne-orientation elindelekileyo ye-IMF iphakamise ngamandla ukuba i-aurora enkulu efunyenwe ngaphakathi kwe-polar cap ye-Northern Hemisphere yayiyi-polar rain aurora. I-interhemispheric asymmetry nayo yabonwa kwidatha ye-electron. Kwakhona, unxulumano phakathi kwexesha lokunyamalala komoya welanga kunye nokuzaliswa kwekepusi yepolar kwakukuhle kakhulu.
Imilinganiselo yokubona evela kwiziko elisezantsi kwidolophu yaseArtic yaseLongyearbyen ngomhla wama-25th -26th UDisemba wabonisa ukuba ii-electron zamandla aphezulu (> 1 keV) zenza icandelo eliphambili lemvula ye-electron. Ukuthontelana kwee-electron zamandla aphezulu nako kwabonwa yisathelayithi. Ngenxa yoko, i-aurora yayibonakala emhlabeni njengokukhutshwa okukhanyayo okuluhlaza.
Kuphononongo lwangaphambili, kwaboniswa ukuba i-aurora yemvula emhlophe ihamba ngokuchasene nelanga kwi-150 yeemitha ngomzuzwana. Kwimeko ye-atypical aurora ebonwe ngobusuku beKrisimesi ka-2022, uhlalutyo lwedatha ye-optical cross-sectional lubonise ukuba i-aurora isasazeke kwicala elichasene nelanga kodwa isantya se-aurora njengoko sibonwa emhlabeni sasiphindwe kabini ukuya kathathu ngokukhawuleza.
Ke, i-aurora enkulu yeyunifomu ebonakalayo emhlabeni ngobusuku beKrisimesi ngo-2022 yayiyi-aurora yemvula yepolar. Olu yayiluqwalaselo lokuqala olusekwe emhlabeni kwipolar rain aurora, inkalo eyodwa yodibaniso oluntsonkothileyo lwe-Sun-Earth.
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Iingxelo:
- Hosokawa, K. okqhubekayo 2024. I-aurora enkulu kakhulu kwi-polar cap ngosuku apho umoya welanga uphantse wanyamalala. INKQUBELA YEZESAYENSI. 21 Juni 2024. Vol 10, Issue 25. DOI: https://doi.org/10.1126/sciadv.adn5276
- SWPC, NOAA. Aurora. Ifumaneka e https://www.swpc.noaa.gov/phenomena/aurora
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