Yanayin Uranus

**Yanayin Uranus** yana da tasiri sosai ta hanyar rashin zafi  a ciki ta, wanda ke iyakance aikin yanayi, da kuma matsanancin juyawa, wanda ke haifar da bambancin yanayi mai tsanani. Yanayin Uranus yana da kyau sosai idan aka kwatanta da sauran manyan taurari waɗanda in ba haka ba yayi kama da juna. Lokacin da Voyager 2 ya tashi ta Uranus a cikin 1986, ya lura da jimlar siffofin girgije goma a duk faɗin duniyar. Bincike daga baya daga ƙasa ko ta Hubble Space Telescope da aka yi a cikin 1990s da 2000s sun bayyana girgije mai haske a arewacin (winter) hemisphere. A shekara ta 2006 an gano wani wuri mai duhu mai kama da Babban Dark Spot a kan Neptune.

## Tsarin banded, iskõki da girgije

Shawarwarin farko na ƙungiyoyi da yanayi a kan Uranus sun zo ne a cikin karni na 19, kamar lura a watan Maris da Afrilu na shekara ta 1884 na fararen ƙungiyar da ke kewaye da ma'aunin Uranus, shekaru biyu kawai bayan "spring" equinox na Uranus.

A cikin 1986 Voyager 2 ta gano cewa za'a iya raba yankin kudancin Uranus zuwa yankuna biyu: mai haske mai haske da duhu mai duhu (duba adadi a dama).  Yankin su yana cikin kimanin -45 digiri na latitude. Ƙananan band da ke kewaye da kewayon latitudinal daga -45 zuwa -50 digiri shine mafi girman fasalin da ke bayyane a Uranus. Ana kiranta "ƙwallo" ta kudu. Ana zaton murfin da wuyan suna da yanki mai zurfi na girgije na methane wanda ke cikin kewayon matsin lamba na 1.3 zuwa 2 bar. Abin takaici Voyager 2 ya isa a lokacin tsawo na kudancin lokacin rani na Uranus kuma bai iya lura da arewacin arewa ba. Koyaya, a ƙarshen shekarun 1990 da farkon ƙarni na ashirin da ɗaya, lokacin da yankin arewacin polar ya zo cikin gani, Hubble Space Telescope (HST) da Keck telescope da farko ba su lura da ƙwallo ko ƙuƙwalwar polar a arewacin arewacin Hemisphere ba. Don haka, Uranus ya bayyana ya zama asymmetric: mai haske a kusa da kudancin kudanci kuma yana da duhu a yankin arewacin ƙwallo na kudanci. A shekara ta 2007, duk da haka, lokacin da Uranus ya wuce equinox, ƙuƙwalwar kudancin kusan ta ɓace, yayin da ƙuƙwalwa ta arewa ta fito kusa da digiri 45 na latitude. Tsarin latitudinal da ake gani na Uranus ya bambanta da na Jupiter da Saturn, wanda ke nuna ƙananan ƙungiyoyi masu launi.&nbsp;

Baya ga tsarin banded mai girma, Voyager 2 ya lura da ƙananan girgije goma masu haske, mafi yawa suna kwance digiri da yawa zuwa arewa daga ƙwallo. A duk sauran fannoni Uranus ya yi kama da duniyar da ta mutu a shekarar 1986. Koyaya, a cikin shekarun 1990s yawan abubuwan da aka lura da girgije mai haske sun karu sosai. An samo mafi yawansu a arewacin arewa yayin da suka fara zama bayyane. Bayani na yau da kullun duk da ba daidai ba game da wannan gaskiyar shi ne cewa girgije mai haske yana da sauƙin ganewa a cikin ɓangaren duhu, yayin da a kudancin kudancin ƙwallo mai haske yana rufe su. Duk da haka, akwai bambance-bambance tsakanin girgije na kowane hemisphere. Girgije na arewa sun fi karami, sun fi kaifi kuma sun fi haske. Sun bayyana suna kwance a wani tsawo mafi girma, wanda ke da alaƙa da gaskiyar cewa har zuwa 2004 (duba ƙasa) ba a lura da girgije na kudancin a cikin wavelength 2.2 micrometers, wanda ke mai hankali ga shawo kan methane, yayin da aka lura da girgizar arewa a kai a kai a cikin wannan wavelengtion band. Rayuwar girgije ta ƙunshi umarni da yawa na girman. Wasu ƙananan girgije suna rayuwa na tsawon sa'o'i, yayin da akalla girgije ɗaya na kudancin ya ci gaba tun lokacin da Voyager ya tashi. Binciken da aka yi kwanan nan ya kuma gano cewa siffofin girgije a kan Uranus suna da alaƙa da waɗanda ke kan Neptune, kodayake yanayin da ke kan Uranus ya fi kwanciyar hankali.&nbsp;

Ba a taɓa ganin tabo masu duhu a kan Neptune ba a kan Uranus kafin 2006, lokacin da aka fara hoton irin wannan fasalin  A cikin wannan shekarar, abubuwan da aka gani daga Hubble Space Telescope da Keck Telescope sun nuna wani ɗan ƙaramin wuri mai duhu a arewacin (hunturu) na Uranus.  An samo shi a latudu na kusan 28 ± 1° kuma an auna shi kusan 2° (1300 km) a cikin latitude da 5° (2700 km) a cikin longitude.  Siffar da ake kira Uranus Dark Spot (UDS) ta motsa a cikin hanyar da ake bi na jujjuyawar Uranus tare da matsakaicin saurin 43.1 ± 0.1 m/s, wanda ya kusan 20 m/s da sauri fiye da gudun girgije a wannan latitude.[5].  Latitude na UDS ya kasance kusan akai-akai.  Siffar ta kasance mai sauye-sauye cikin girma da kamanni kuma galibi tana tare da wani farin girgije mai haske mai suna Bright Companion (BC), wanda ke tafiya da kusan gudu ɗaya da UDS kanta..&nbsp;&nbsp;

Halin da bayyanar UDS da abokinsa mai haske sun yi kama da Neptunian Great Dark Spots (GDS) da abokansu masu haske, bi da bi, kodayake UDS ya fi karami. Wannan kamanceceniya tana nuna cewa suna da asali iri ɗaya. An yi la'akari da GDS a matsayin vortices na anticyclonic a cikin yanayi na Neptune, yayin da aka yi tunanin abokan aikinsu masu haske su ne girgije na methane da aka kafa a wurare, inda iska ke tashi (girgije na orographic).  UDS ya kamata ya sami irin wannan yanayi, kodayake ya bambanta da GDS a wasu tsawo. Kodayake GDS yana da bambanci mafi girma a 0.47 μm, UDS ba a guguwa a wannan tsawo ba. A gefe guda, UDS ya nuna bambanci mafi girma a 1.6 μm, inda ba a gano GDS ba. Wannan yana nuna cewa wurare masu duhu a kan manyan kankara guda biyu suna cikin matakai daban-daban na matsin lamba - fasalin Uranian mai yiwuwa yana kusa da 4 bar. Launi mai duhu na UDS (kazalika da GDS) na iya haifar da taƙaicewar hydrogen sulfide ko ammonium hydrosulfide.&nbsp;&nbsp;&nbsp;

Fitowar wani wuri mai duhu a kan hemisphere na Uranus wanda ya kasance cikin duhu na shekaru da yawa yana nuna cewa kusa da equinox Uranus ya shiga wani lokaci na aikin yanayi mai girma.

### Iska
Binciken siffofin girgije da yawa ya ba da damar ƙaddamar da iskar yanki da ke hurawa a saman troposphere na Uranus. A ma'auni iska suna retrograde, wanda ke nufin cewa suna busawa a cikin juyawa zuwa juyawa na duniya. Saurin su yana daga -100 zuwa -50 m/s. Saurin iska yana ƙaruwa tare da nesa daga ma'auni, yana kaiwa ƙimar sifili kusa da ± 20 ° latitude, inda mafi ƙarancin zafin jiki na troposphere yake.   Kusa da sanduna, iskõki suna canzawa zuwa hanyar ci gaba, suna gudana tare da juyawa. Saurin iska yana ci gaba da ƙaruwa yana kaiwa mafi girma a ± 60 ° latitude kafin ya faɗi zuwa sifili a sanduna. Saurin iska a -40 ° latitude ya kasance daga 150 zuwa 200 m / s. Saboda wuyan yana rufe duk girgije da ke ƙasa da wannan layi daya, saurin tsakanin shi da kudancin ba zai yiwu a auna ba. Sabanin haka, a arewacin arewacin arewa ana lura da saurin gudu har zuwa 240 m / s kusa da digiri +50 na latitude.   Wadannan saurin wani lokaci suna haifar da maganganun da ba daidai ba cewa iskõki suna da sauri a arewacin arewa. A zahiri, latitude ta latitude, iskõki suna da ɗan jinkiri a arewacin Uranus, musamman a tsakiyar latitudes daga ±20 zuwa ±40 digiri. A halin yanzu babu wata yarjejeniya game da ko duk wani canji a cikin saurin iska ya faru tun 1986,   kuma babu wani abu da aka sani game da iskõki masu saurin gaske.&nbsp;&nbsp;&nbsp;

## Bambancin yanayi
Tabbatar da yanayin wannan bambancin yanayi yana da wahala saboda bayanai masu kyau game da yanayin Uranus sun wanzu ƙasa da shekara ɗaya ta Uranian (shekaru 84 na Duniya).  Duk da haka an yi binciken da yawa. Photometry a cikin rabin shekara ta Uranian (farawa a cikin 1950s) ya nuna bambancin yau da kullun a cikin haske a cikin bands biyu, tare da maxima da ke faruwa a solstices da minima da ke faruwa ne a equinoxes. Irin wannan bambancin lokaci, tare da maxima a solstices, an lura da shi a cikin ma'aunin microwave na zurfin troposphere da aka fara a cikin shekarun 1960. Ma'aunin zafin jiki na Stratospheric wanda ya fara a cikin 1970s ya nuna matsakaicin dabi'u kusa da 1986 solstice.

Yawancin wannan bambancin an yi imanin cewa yana faruwa ne saboda canje-canje a cikin yanayin kallo. Uranus wani nau'i ne mai laushi, wanda ke haifar da yanki da ake gani ya zama babba idan aka kalli shi daga sanduna. Wannan ya bayyana a wani bangare bayyanarsa mai haske a solstices. An kuma san Uranus da nuna bambance-bambance masu karfi a cikin albedo (duba sama).  Misali, yankin kudancin Uranus ya fi haske fiye da bands na equatorial. Bugu da kari, duka sanduna biyu suna nuna haske mai tsawo a cikin ɓangaren microwave na bakan,  yayin da aka san stratosphere na polar ya fi sanyi fiye da na equatorial.  Don haka canjin yanayi yana faruwa kamar haka: sanduna, waɗanda suke da haske a cikin bands masu ganuwa da microwave, suna zuwa cikin ra'ayi a solstices wanda ke haifar da duniyar da ta fi haske, yayin da duhu mai duhu yana bayyane galibi kusa da equinoxes wanda ke haifar a duniyar da tafi duhu. Bugu da kari, ɓoyewa a solstices suna bincika zafi mai zafi na equatorial stratosphere.

Koyaya, akwai wasu dalilai na gaskata cewa canje-canje na yanayi suna faruwa a Uranus. Kodayake an san Uranus da yankin kudancin da ke da haske, arewacin arewacin yana da duhu, wanda bai dace da samfurin canjin yanayi da aka tsara a sama ba. A lokacin da ya gabata na arewa a cikin 1944, Uranus ya nuna matakan haske, wanda ke nuna cewa arewacin arewa ba koyaushe ba ne. Wannan bayyane yana nuna cewa ginshiƙi mai ganuwa yana haskakawa wani lokaci kafin solstice kuma yana duhu bayan equinox. Cikakken bincike game da bayanan da ake gani da microwave ya nuna cewa sauye-sauyen lokaci-lokaci na haske ba cikakke ba ne a kusa da solstices, wanda kuma ke nuna canji a cikin tsarin albedo. Bugu da kari, bayanan microwave sun nuna karuwa a bambancin ma'auni bayan 1986 solstice. A ƙarshe a cikin shekarun 1990s, yayin da Uranus ya ƙaura daga solstice, Hubble da telescopes na ƙasa sun bayyana cewa kudancin polar cap ya yi duhu sosai (sai dai kudancin collar, wanda ya kasance mai haske),  yayin da arewacin arewacin arewa ya nuna karuwar aiki,  kamar tsarin girgije da iskõki masu ƙarfi, suna da ƙarfafa tsammanin cewa zai haskaka nan ba da daɗewa ba. Musamman, ana sa ran wani analog na haske mai haske wanda ke cikin kudancinsa a -45 ° zai bayyana a arewacinsa. Wannan ya faru ne a shekara ta 2007 lokacin da Uranus ya wuce equinox: wani karamin wuyan arewacin ya tashi, yayin da wuyan kudancin ya zama kusan ba a ganuwa, kodayake bayanin iska na yanki ya kasance ba daidai ba, tare da iskar arewa ta kasance dan kadan fiye da kudanci.

Hanyar canje-canje na jiki har yanzu ba a bayyana ba. Kusa da lokacin rani da hunturu, sassan Uranus suna kwance ko dai a cikin cikakken haske na hasken rana ko fuskantar sararin samaniya. Ana zaton haskakawar hasken rana ya haifar da kauri na girgije na methane da yadudduka masu haushi da ke cikin troposphere. Har ila yau, ƙuƙwalwar mai haske a -45 ° latitude tana da alaƙa da girgije na methane. Sauran canje-canje a yankin kudancin polar za a iya bayyana su ta hanyar canje-canje da ke cikin ƙananan girgije. Bambancin fitowar microwave daga Uranus mai yiwuwa ya haifar da canje-canje a cikin zurfin yaduwar tropospheric, saboda girgije mai zurfi da haze na iya hana convection.

A cikin ɗan gajeren lokaci a rabi na biyu na shekara ta 2004, yawancin manyan girgije sun bayyana a cikin yanayi Uranian, suna ba shi kamannin Neptune. Binciken ya haɗa da saurin iska mai rikodin 824 km / h da kuma tsawa mai tsawo da ake kira "Fourth of July fireworks". Me ya sa wannan hauhawar kwatsam a cikin aiki ya kamata ya faru ba a san shi ba, amma ya bayyana cewa matsanancin juyawa na Uranus yana haifar da bambancin yanayi a cikin yanayin sa.&nbsp;

## Misalai na zirga-zirga

An ba da shawarar mafita da yawa don bayyana yanayin kwanciyar hankali akan Uranus.  Ɗayan bayanin da aka yi niyya don wannan ƙarancin sifofin girgije shine cewa Uranus na ciki yana bayyana ƙasa da na sauran manyan taurari;  ta fuskar falaki, tana da }aramar magudanar zafin jiki.  Me yasa zafin zafin Uranus yayi ƙasa da ƙasa har yanzu ba a gane ba.  Neptune, wanda shine tagwayen Uranus kusa da girmansa da tsarinsa, yana haskakawa sau 2.61 yawan kuzari zuwa sararin samaniya kamar yadda yake samu daga Rana.  Uranus, akasin haka, yana haskakawa da ƙyar ƙuruciyar zafi ko kaɗan.  Jimlar ƙarfin da Uranus ke haskawa a cikin infrared mai nisa (watau zafi) ɓangaren bakan shine sau 1.06 ± 0.08 na hasken rana da ke shanye cikin yanayin sa.  A haƙiƙa, yanayin zafi na Uranus shine kawai 0.042 ± 0.047 W/m2, wanda yayi ƙasa da yanayin zafi na ciki na Duniya kusan 0.075 W/m2. Mafi ƙarancin zafin jiki da aka rubuta a cikin tropopause na Uranus shine 49 K (-224 °C), wanda ya sa Uranus ya zama duniya mafi sanyi a cikin Tsarin Rana, sanyi fiye da Neptune.

Wani ra'ayi ya bayyana cewa lokacin da Uranus ya "kusa" ta hanyar tasirin supermassive wanda ya haifar da matsanancin juyawa, taron kuma ya sa ya fitar da mafi yawan zafin jikinsa na farko, ya bar shi tare da matsanancin zafin jiki. Wani ra'ayi shi ne cewa wasu nau'ikan shingen sun wanzu a cikin matakan Uranus na sama wanda ke hana zafin core daga isa farfajiya. Misali, convection na iya faruwa a cikin saiti na nau'o'i daban-daban, wanda zai iya hana jigilar zafi sama.

## Manazarta