shukr


shukr The Venusian symbol, a circle with a small equal-armed cross beneath it
Venus in approximately true-color, a nearly uniform pale cream, although the image has been processed to bring out details.[1] The planet's disk is about three-quarters illuminated. Almost no variation or detail can be seen in the clouds.
shukr vaastavik rang mein, satah baadalon ki ek moti chaadar se chhip gaya hai.
upanaam
visheshan Venusian or (rarely) Cytherean, Venerean
yug J2000
upasaur
  • 10,89,39,000 kimi
  • 0.728213 AU
apasaur
  • 10,74,77,000 kimi
  • 0.718440 AU
ardh mukhya aksh
  • 10,82,08,000 kimi
  • 0.723327 AU
vikendrata 0.006756
parikraman kaal
  • 224.698 diwas
  • 0.615 190 varsh
  • 1.92 shukr saur diwas
sanyuti kaal 583.92 days[3]
ausat parikraman gati 35.02 kimi/second
maadhya konaantar 50.115°
jhukaav
  • 3.394 58° kraantivrutt se
  • 3.86° soorya ke vishuvavrutt se
  • 2.19° avikaari tal se[4]
aaroh paat ka anulamb 76.678°
Argument of perihelion 55.186°
upagrah koi naheen
bhautik visheshataaeain
maadhya trijya
  • 6,051.8 ± 1.0 km[5]
  • 0.9499 pruthvi
sapaatata 0[5]
tal-kshetrafal
  • 4.60 x 108 kimi2
  • 0.902 pruthvi
aayatan
  • 9.28 x 1011 kimi3
  • 0.866 pruthvi
dravyamaan
  • 4.868 5×a1024 kigra
  • 0.815 pruthvi
maadhya ghanatv 5.243 gram/semi3
vishuvateeya satah gurutvaakarshan
  • 8.87 meter/second2
  • 0.904 gram
palaayan veg 10.36 kimi/second
naakshatr ghoornan
kaal
−243.018 diwas (pratigaami)
vishuvateeya ghoornan veg 6.52
aksheeya naman 177.3°[3]
uttari dhruv daayaan adhirohan
  • 18 ghante 11 minute 2 second
  • 272.76°[6]
uttari dhruvavanaman 67.16°
albedo
  • 0.67 (jyaamiteeya)[7]
  • 0.90 (baand)[7]
satah ka taapamaan
Kelvin
Celsius
nyoon maadhya adhi
735 K[3][11][12]
462 °aC
spasht parimaan
  • sarvaadhik chamak −4.9[8][9] (ardhachandr)
  • −3.8[10] (poornachandr)
koneeya vyaas 9.7"–66.0"[3]
vaayu-mandal
satah par daab 92 bar (9.2 MPa)
sanghatan

shukr (Venus), soorya se doosra grah hai aur pratyek 224.7 pruthvi dinon me soorya parikrama karta hai |[13] grah ka naamakaran prem aur saundarya ki roman devi par hua hai | chandrama ke baad yeh raatri aakaash mein sabse chamakeeli praakrutik vastu hai | iska aabhaasi parimaan -4.6 ke star tak pahuainch jaata hai aur yeh chhaaya daalne ke lae paryaapt ujjavalata hai |[14] chooainki shukr ek avar grah hai isliye pruthvi se dekhne par yeh kabhi soorya se door nazar naheen aata hai: iska prasarakon 47.8 degree ke adhiktam tak pahuainchata hai | shukr sooryodaya se pehle ya sooryaast ke baad keval thodi der ke lae hi apni adhiktam chamak par pahuainchata hai | yaheen kaaran hai jiske liye yeh praacheen sanskrutiyon ke dvaara subah ka taara ya shaam ka taara ke roop mein sandarbhit kiya gaya hai |

shukr ek sthaleeya grah ke roop mein vargeekrut hai aur samaan aakaar, gurutvaakarshan aur sanrachana ke kaaran kabhi kabhi use pruthvi ka "bahan grah" kaha gaya hai | shukr aakaar aur doori donon me pruthvi ke niktatam hai | haalaanki anya maamalon mein yeh pruthvi se ekdam alag nazar aata hai | shukr salfyoorik esid yukt atyadhik paraavartak baadalon ki ek apaaradarshi parat se dhainka hua hai| jisne iski satah ko drushya prakaash mein antariksh se nihaarane se bacha rakha hai | iska vaayumandal chaar sthaleeya grahon me saghanatam hai aur adhikaaainshat: kaarban daaioksaaid se bana hai | grah ki satah par vaayumandaleeya dabaav pruthvi ki tulana me 92 guna hai | 735° K (462°aC,863°aF) ke ausat satahi taapamaan ke saath shukr saur mandal me ab tak ka sabse tapt grah hai | kaarban ko chattaanon aur satahi bhooaakrutiyon mein vaapas jakadne ke liye yahaaain koi kaarban chakr maujood nahi hai aur na hi jeevadravya ko isame avashoshit karne ke liye koi kaarbanik jeevan yahaaain nazar aata hai | shukr par ateet mein mahaasaagar ho sakte hai[15]lekin anvarat greenahaaus prabhaav ke kaaran badhte taapamaan ke saath vah vaashpeekrut hote gaye honge |[16] paani ki adhikaansh sambhaavana prakaash-viyojit (Photodissociation) rahi hone ki, va, graheeya chunbakeeya kshetr ke abhaav ki vajah se, mukt haaidrojan saur vaayu dvaara grahon ke beech antariksh mein baha di gayi hai.[17]shukr ki bhoomi bikhre shilaakhandon ka ek sookha marudyaan hai aur samay-samay par jvaalaamukheekaran dvaara tarotaaja ki hui hai.

anukram

bhautik lakshan

shukr chaar saur sthaleeya grahon mein se ek hai | jiska arth hai ki pruthvi ki hi tarah yeh ek chattaani pind hai | aakaar va dravyamaan mein yeh pruthvi ke samaan hai aur aksar pruthvi ki "bahan" ya "judva " ke roop mein varnit kiya gaya hai |[18] shukr ka vyaas 12,092 kimi (pruthvi ki tulana mein keval 650 kimi kam) aur dravyamaan pruthvi ka 81.5% hai | apne ghane kaarban daaioksaaid yukt vaataavaran ke kaaran shukr ki satahi paristhitiyaaain pruthvi par ki tulana me bilkul bhinn hai | shukr ke vaayumandaleeya dravyamaan ka 96.5% kaarban daaioksaaid aur shesh 3.5% ka adhikaansh naaitrojan raha hai |[19]

bhoogol

20 veen sadi mein graheeya vigyaan dvaara kuchh satahi rahasyon ko ujaagar karne tak shukr ki satah atkalon ka vishay thi | antat: iska 1990-91 mein maigalan pariyojana dvaara vistaar mein maapan kiya gaya | yahaaain ki bhoomi vistrut jvaalaamukheekaran ke pramaan pesh karti hai aur vaataavaran mein salfar vahaaain haal hi mein hue kuchh udagaar ka sanket ho sakti hai |[20][21]

shukr ki satah ka kareeban 80% hissa chikne aur jvaalaamukheeya maidaanon se aachhaadit hai | jinmein se 70% salavati choteedaar maidaanon se va 10% chikni ya lodaar maidaanon se bana hai.[22]do uchchabhoomi " mahaadveep " iske satahi kshetr ke shesh ko sanvaarata hai jisme se ek grah ke uttari golaardh aur ek anya bhoomadhyarekha ke bas dakshin mein sthit hai. uttari mahaadveep ko bebeelon ke pyaar ki devi ishtaar ke naam par ishtaar tera kaha gaya hai aur aakaar takareeban Australia jitna hai. shukr ka sarvochch parvat Maxwell montes ishtaar tera par sthit hai. iska shikhar shukr ki ausat satahi uchchataansh se 11 kimi oopar hai. dakshini mahaadveep efrodaait tera greek ki pyaar ki devi ke naam par hai aur lagbhag dakshin America ke aakaar ka yeh mahaadveep donon uchchabhoom kshetron mein bada hai. daraaron aur bhransho ke sanjaal ne is kshetr ke adhikaaainsh bhaag ko ghera hua hai.[23]

shukr par drushyamaan kisi bhi jvaalaamukh-kund ke saath laava pravaah ke pramaan ka abhaav ek paheli bana hua hai | grah par kuchh prahaar kretar hai jo satah ke apekshaakrut yuva hone ka pradarshan karte hai aur lagbhag 30-60 karod saal puraane hai |[24][25] aamtaur par sthaleeya grahon par paae jaane vaale prahaar kretaron, pahaadon aur ghaatiyon ke alaava, shukr par anekon adviteeya bhaugolik sanrachanaaen hai. in sanrachanaaon mein, chapate shikhar waali jvaalaamukhi sanrachanaaen "fera" kahalaati hai, yeh kuchh maalapuaa jaisi dikhti hai aur aakaar mein 20-50 kimi vistaar mein hoti hai. 100-1,000 meter ooainchi daraar yukt sitaara-sadrushya chakreeya pranaali ko "nova" kaha jaata hai. chakreeya aur sankeindrit daraaron, donon ke saath makadi ke jaale se milti-julati sanrachanaaen "arkanoid" ke roop mein jaani jaati hai. "korona" daraaron se saje vruttaakaar chhalle hai aur kabhi-kabhi gaddhon se ghire hote hai. in sanrachanaaon ke mool jvaalaamukhi mein hain.[26]

shukr ki adhikaansh satahi aakrutiyon ko aitihaasik aur pauraanik mahilaaon ke naam par rakha gaya hain |[27] lekin James Clark Maxwell par naamit Maxwell montes aur uchchabhoomi kshetron alfa reejiyo, beeta reejiyo aur ovada reejiyo kuchh apavaad hai | poorv ki in teen bhooaakrutiyon ko antaraashtreeya khagoleeya sangh dvaara apnaai gayi maujooda pranaali se pehle naamit kiya gaya hai | antaraashtreeya khagoleeya sangh graheeya naamakaran ki dekharekh karta hai |[28]

shukr par bhautik aakrutiyon ke deshaantaron ko unki pradhaan madhyaahn rekha ke saapeksh vyakt kiya gaya hai | mool pradhaan madhyaahn rekha alfa reejiyo ke dakshin me sthit ujjval andaakaar aakruti "ev" ke kendra se hokar gujarati hai |[29] venara mission poora hone ke baad, pradhaan madhyaahn rekha ko eriyaadan kretar se hokar paarit karne ke liye nae sire se paribhaashit kiya gaya tha |[30][31]

bhootal bhoovijnyaaan

A false color image of Venus: Ribbons of lighter color stretch haphazardly across the surface. Plainer areas of more even colouration lie between.
1990-1994 ke beech maigalan radaar se pratichitrit satah ki vaishvik radaar chhavi

shukr ki adhiktar satah jvaalaamukhi gatividhi dvaara nirmit najar aati hai. shukr par pruthvi ki tarah anekaanek jvaalaamukhi hai aur iske pratyek 100 kimi ke daayare me kuchh 167 ke aaspaas bade jvaalaamukhi hai | pruthvi par is aakaar ki jvaalaamukhi jatilta keval havaai ke bade dweep par hai |[26] yeh isliye naheen ki shukr jvaalaamukhi najriye se pruthvi ki tulana mein adhik sakriya hai, balki iski parpati puraani hai | pruthvi ki samudri parpati vivrtanik pleton ki seemaaon par bhoogarbhiya prakriya dvaara nirantar punarnaveekrut kar di jaati hai aur kareeb 10 karod varsh ausat umr ki hai,[32] jabki shukr ki satah 30-60 karod varsh puraani hone ka anumaan hai |[33]

shukr par avirt jvaalaamukheeta ke liye anek pramaan bindu maujud hai | soviyt venera kaaryakram ke dauraan, venera 11 aur venera 12 prob ne bijli ke ek nirantar pravaah ka pata lagaaya aur venera 12 ne apne avataran ke baad ek shaktishaali garjan ki karataal darj ki | Europeeya antariksh agency ke Venus express ne uainche vaayumandal mein prachur maatra mein bijli darj ki |[34] jabki pruthvi par baarish garaj-toofaan laati hai, vaheen shukr ki satah par koi varsha naheen hoti hai (haalaanki upari vaayumandal mein yeh varsha salfyurik aml karta hai jo satah se kareeb 25 kimi upar vaashpeekrut kar di jaati hai). ek sambhaavana hai ek jvaalaamukhi visfot se udi raakh ne bijli paida ki thi | ek anya pramaan vaayumandal mein maujud salfar daaioksaaid saandrata ke maap se aata hai, jise 1978 aur 1986 ke beech ek 10 ke kaarak ke saath bundon se paaya gaya tha. This may imply the levels had earlier been boosted by a large volcanic eruption.[35]

shukr ke satah par prahaar kretar (chhavi radaar deta se punarnirmit hai.

shukr par samooche hajaar bhar prahaar kretar satah bhar me samaan rup se vitrit hai | pruthvi aur chandrama jaise anya kretarayukt nikaayon par, kretar giraavat ki avasthaaon ki ek range dikhaate hai | chandrama par giraavat ka kaaran uttarottar tkkar hai, to vaheen pruthvi par yeh hava aur baarish ke kataav ke kaaran hoti hai | shukr par lagbhag 85% kretar praacheen haalat mein hain | kretaron ki sankhya, apni susanrakshit paristhiti ke saanidhya ke saath, kareeb 30-60 karod varsh poorv ki ek vaishvik punarsataheekaran ghatna ke adheen is grah ke gujarane ka sanket karti hai,[36][37] jvaalaamukheekaran me patan ka anusaran karti hai |[38] jahaan ek or pruthvi ki parpati nirantar prakriyaarat hai, vaheen shukr ko is tarah ki prakriya ke poshan ke liye asamarth samjha gaya hai | bina plate vivrtaniki ke baavajud apne meintal se garmi failaane ke liye shukr ek chakreeya prakriya se hokar gujarata hai jismein meintal taapamaan vruddhi parpati ke kamjor hone ke liye aavashyak charam star tak pahunchane tak jaari rahati hai | fir, lagbhag 10 karod varshon ki avadhi mein dabaav ek vishaal paimaane par hota hai jo parpati ka poori tarah se punarnaveekaran kar deta hai |[26]

shukr kretaron ke paraas vyaas mein 3 kimi se lekar 280 kimi tak hai. aagantuk nikaayon par ghane vaayumandal ke prabhaav ke kaaran 3 kimi se kam koi kretar naheen hai. ek nishchit gatij oorja se kam ke saath aane waali vastuon ko vaayumandal ne itna dheema kiya hain ki vein ek prahaar kretar naheen bana paate hai |[39] vyaas me 50 kimi se kam ke aane vaale prakshyep khand-khand ho jaaenge aur satah par pahunchane se pehle hi vaayumandal mein bhasm ho jaaenge.[40]

aantarik sanrachana

bhookampeeya deta ya jadtvaaghoorn ki jaankaari ke bagair shukr ki aantarik sanrachana aur bhoo-rasaayan ke baare mein thodi hi pratyaksh jaankaari upalabdh hai.[41] shukr aur pruthvi ke beech aakaar aur ghanatv mein samaanata bataati hai, vein samaan aantarik sanrachana saajha karti hai: ek kor, ek meintal aur ek krast. pruthvi par ki hi tarah shukr ka kor kam se kam aanshik roop se taral hai kyonki in do grahon ke thande hone ki dar lagbhag ek samaan rahi hai.[42] shukr ka thoda chhota aakaar bataata hai, iske gahre aantarik bhaag mein dabaav pruthvi se kaafi kam hain. in do grahon ke beech pramukh antar hai, shukr par plate tektoniks ke liye pramaan ka abhaav, possibly because its crust is too strong to subduct without water to make it less viscous. This results in reduced heat loss from the planet, preventing it from cooling and providing a likely explanation for its lack of an internally generated magnetic field.[43] baavajud, shukr pramukh punarsataheekaran ghatnaaon mein apni aantarik ooshma beech beech mein kho sakta hain.[36]

vaataavaran aur jalavaayu

1979 mein pioneer Venus orbitr se paraabaingani prekshanon se pragat shukr ki vaayumandaleeya meghaakruti
pruthvi ke vaayumandal ke anurup ek saral gas mishran ka sinthetik stick avashoshan spectrum
shukr ki vaayumandaleeya sanrachana HITRAN deta par aadhaarit hai,[44] jo web pranaali par Hitran ka upayog kar banaai gayi hai.[45] hara rang-jal vaashp, laal rang-kaarban daaioksaaid, WN - tarang sankhya (chetaavani: anya rangon ke bhinn arth hai, nimn tarang dairdhya daanye par aur uchch baain taraf hai.)

shukr ka vaayumandal atyant ghana hai, jo mukhya roop se kaarban daaioksaaid aur naaitrojan ki ek chhoti maatra se milkar bana hai | vaayumandaleeya dravyamaan pruthvi par ke vaayumandal ki tulana me 93 guna hai, jabki grah ke satah par ka dabaav pruthvi par ke satahi dabaav ki tulana me 92 guna hai- yeh dabaav pruthvi ke mahaasaagaron ki ek kilometer kareeb ki gaharaai par paaye jaane vaale dabaav ke baraabar hai | satah par ghanatv 65 kilo/ghanameetar hai (paani ki tulana mein 6.5%) | yahaan ka CO2-bahul vaayumandal, salfar daaioksaaid ke ghane baadalon ke saath-saath, saur mandal ka sabse shaktishaali green house prabhaav utpann karta hai aur kam se kam 462 °aC (864 °aF) ka satahi taapamaan paida karta hai |[11][46] yeh shukr ki satah ko budh ki tulana mein jyaada tapt banaata hai | budh ka nyoonatam satahi taapamaan −220 °aC aur adhiktam satahi taapamaan 420 °aC hai |[47] shukr grah soorya se doguni ke kareeb doori par hone ke baavajud budh saur vikirn (irradiance) ka keval 25% praapt karta hai | praay: shukr ki satah naarakeeya roop mein varnit hai |[48] This temperature is even higher than temperatures used to achieve sterilization. (See also: Hot air oven)

adhyayanon ne bataaya hai ki shukr ka vaataavaran haal ki tulana mein arabon saal pehle pruthvi ki tarah bahut jyaada tha aur vahaan satah par taral paani ki paryaapt maatra rahi ho sakti hai | lekin, 60 karod se lekar kai arab varshon tak ki avadhi ke baad,[49] mool paani ke vaashpeekaran ke kaaran ek daudata-bhaagata greenahaaus prabhaav hua, jisne vahaan ke vaataavaran mein ek mahatvapoorn star ki green house gaison ko paida kiya |[50] haalaanki grah par satahi haalaat kisi bhi pruthvi-sadrushya jeevan ke liye lambi mehmaan navaaji yogya naheen hai, jo is ghatna ke pehle rahe ho sakte hai | yeh sambhaavana ki ek rahane yogya doosari jagah nichle aur madhyam baadal paraton mein maujud hai, shukr ab bhi daud se baahar naheen hua hai |[51]

taapeeya jadta aur nichle vaayumandal mein havaaon dvaara ushma ke hastaantaran ka matlab hai ki shukr ki satah ke taapamaan raat aur din ke pakshon ke beech kaafi bhinn naheen hote hai, baavajud iske ki grah ka ghoornan atyadhik dheema hai. satah par havaaen dheemi hain, prati ghante kuchh hi kilometer ki doori chalti hai, lekin shukr ke satah par vaataavaran ke uchch ghanatv ki vajah se, ve avarodhon ke khilaaf ullekhaneeya maatra ka bal daalati hai aur satah bhar mein dhool aur chhote pattharon ka parivhan karti hai. yeh akela hi isse hokar maanaveeya chahal kadami ke liye mushkil khadi karta hoga, anyatha garmi, dabaav aur okseejan ki kami koi samasya naheen thi.[52]

saghan CO2 parat ke oopar ghane baadal hain jo mukhya rup se salfar daaioksaaid aur salfyoorik aml ki boondon se milkar bane hai.[53][54] ye baadal lagbhag 90% soorya prakaash ko paraavartit va bikherate hai jo ki vaapas antariksh mein un par girta hai aur shukr ki satah ke drushya prekshan ko rokate hai. baadalon ke sthaayi aavaran ka arth hai ki bhale hi shukr grah pruthvi ki tulana mein soorya se najadeek hai, par shukr ki satah achhi tarah se tapi naheen hai. baadalon ke sheersh par ki 300 kimi/ghanta ki shaktishaali havaaen har chaar se paanch pruthvi divso mein grah ka chakkar lagaati hai.[55] shukr ki havaaen usaki ghoornan ke 60 gune tak gatisheel hai, jabki pruthvi ki sabse tej havaaen ghoornan gati ki keval 10% se 20% hain.[56]

shukr ki satah prabhaavi dhang se samataapeeya hai, yeh na sirf din aur raat ke beech balki bhoomadhya rekha aur dhruvon ke madhya bhi ek sthir taapamaan banaae rakhata hai |[3][57] grah ka alp aksheeya jhukaav (kam se kam teen degree, tulana ke liye pruthvi ka 23 degree) bhi mausami taapamaan vividhta ko kam karta hai |[58] taapamaan mein ullekhaneeya bhinnata keval oonchaai ke saath milti hai | In 1995, the Magellan probe imaged a highly reflective substance at the tops of the highest mountain peaks that bore a strong resemblance to terrestrial snow. This substance arguably formed from a similar process to snow, albeit at a far higher temperature. Too volatile to condense on the surface, it rose in gas form to cooler higher elevations, where it then fell as precipitation. The identity of this substance is not known with certainty, but speculation has ranged from elemental tellurium to lead sulfide (galena).[59]

shukr ke baadal pruthvi par ke baadalon ki hi tarah bijli paida karne mein saksham hain.[60] bijli ki maujudagi vivaadit rahi hai jab se soviyt venera prob dvaara pratham sandehaaspad bauchhaar ka pata lagaaya gaya tha. 2006-07 mein Venus express ne spasht roop se vhistalar mod tarangon ka pata lagaaya, jo bijli ka chinhak hai | unki aantaraayik upasthiti mausam gatividhi se jude ek paitarn ko ingit karta hai. bijli ki dar pruthvi par ki tulana mein kam se kam aadhi hai.[60] 2007 mein Venus express prob ne khoj ki ki ek vishaal dohara vaayumandaleeya bhanvar grah ke dakshini dhruv par maujood hai.[61][62]

2011 mein Venus express prob dvaara ek anya khoj ki gayi aur vah hai, shukr ke vaataavaran ki oonchaai mein ek ojon parat maujood hai |[63]

29 January 2013 ko iesae ke vaigyaaniko ne bataaya ki shukr grah ka aayanamandal baahar ki or bahata hai, jo is maayane mein samaan hai "isi tarah ki paristhitiyon mein ek dhoomaketu se aayan poonchh ki bauchhaar hoti dekhi gayi"."[64][65]

chunbakeeya kshetr aur kor

sthaleeya grahon ke aakaar ki tulana (baaen se daaen) budh, shukr, pruthvi aur mangal vaastavik rango mein

1967 mein venera 4 ne shukr ke chunbakeeya kshetr ko pruthvi ki tulana mein bahut kamjor paaya. yeh chunbakeeya kshetr ek aantarik daainemo, pruthvi ke andaruni kor ki tarah, ki bajaay aayanamandal aur saur vaayu ke beech ek ant:kriya dvaara prerit hai.[66][67] shukr ka chhota sa prerit chunbakeeya kshetr vaayumandal ko brahmaandeeya vikirn ke khilaaf naganya suraksha pradaan karta hai | yeh vikirn baadal dar baadal bijli nirvahan ka parinaam ho sakta hai.[68]

aakaar mein pruthvi ke baraabar hone ke baavajud shukr par ek aantarik chunbakeeya kshetr ki kami hona aashcharya ki baat thi | yeh bhi ummeed thi ki iska kor ek daainemo rakhata hai. ek daainemo ko teen cheejon ki jarurat hoti hai: ek suchaalak taral, ghoornan aur sanvahan. kor ko vidyut pravaahakeeya hona maana gaya hai, jabki iske ghoornan ko praay: bahut jyaada dheemi gati ka hona maana gaya hai, simuleshan dikhaate hai ki ek daainemo nirmaan ke liye yeh paryaapt hai.[69][70] iska taatparya hai, daainemo gum hai kyonki shukr ke kor mein sanvahan ki kami hai. pruthvi par, sanvahan kor ke baahari parat me paaya jaata hai kyonki tali ki taral parat sheersh ki tulana mein bahut jyaada tapt hai. shukr par, ek vaishvik punarsataheekaran ghatna ne plate vivrtaniki ko band kar diya ho sakta hai aur yeh bhoopatal se hokar ushma pravaah ke ghataav ka kaaran bana. isne meintal taapamaan ko badhne ke liye prerit kiya, jisse kor ke baahar ushma pravaah badh gaya. nateejatan, ek chunbakeeya kshetr chalaane ke liye koi aantarik bhoodaainemo upalabdh naheen hai | iske bajaay, kor se nikalne waali taapeeya oorja bhoopatal ko dobaara garm karne ke liye baar-baar istemaal hui hai.[71]

ek sambhaavana yeh ki shukr ka koi thos bheetari kor naheen hai,[72] ya iska kor vartamaan mein thanda naheen hai, isliye kor ka poora taral hissa lagbhag ek hi taapamaan par hai. ek aur sambhaavana ki iska kor pehle se hi poori tarah jam gaya hai. kor ki avastha gandhak ke saandran par atyadhik nirbhar hai, jo filhaal agyaat hai.[71]

shukr ke irdagird durbal chunbakeeya aavaran ka matlab hai saur vaayu grah ke baahya vaayumandal ke saath seedhe sampark karti hai. yahaan, haaidrojan va okseejan ke aayan paraabaingani vikirn se nikle tatasth anuon ke viyojan dvaara banaaye gaye hai. saur vaayu fir oorja ki aapoorti karti hai jo inmein se kuchh aayanon ko grah ke chunbakeeya kshetr se palaayan ke liye paryaapt veg deti hai. is ksharan prakriya ka parinaam nimn-dravyamaan haaidrojan, heeliym aur okseejan aayanon ki haani ke rup me hoti hai, jabki uchch-dravyamaan anuon, jaise ki kaarban daaioksaaid, ko usi tarah se jyaada banaaye rakhane ke liye hoti hai. saur vaayu dvaara vaayumandaleeya ksharan grah ke gathan ke baad ke arabon varshon ke daramyaan jal ke khone ka shaayad sabse bada kaaran bana. is ksharan ne upari vaayumandal mein uchch-dravyamaan dyooteriym se nimn-dravyamaan haaidrojan ke anupaat ko nichle vaayumandal mein anupaat ka 150 guna badha diya hai.[73]

parikrama evam ghoornan

shukr ki kaksha (peeli) aur pruthvi ki kaksha (neeli) ki aapas me tulana I

shukr kareeban 0.72 eyoo (10,80,00,000 kimi; 6,70,00,000 meal) ki ek ausat doori par soorya ki parikrama karta hai aur har 224.65 diwas ko ek chakkar poora karta hai. yadyapi sabhi graheeya kakshaaen deerghavrutteeya hain, shukr ki kaksha 0.01 se kam ki ek vikendrata ke saath, vruttaakaar ke jyaada kareeb hai.[3] jab shukr grah, pruthvi aur soorya ke beech sthit hota hai, yeh sthiti avar sanyojan kahalaati hai, jo usaki pahunch ko pruthvi se niktatam banaati hai, anya grah 4.1 karod ki ausat doori par hai.[3] shukr ausatan har 584 dinon mein avar sanyojan par pahuainchata hai.[3] pruthvi ki kaksha ki ghatati vikendrata ke kaaran, yeh nyoonatam doori daseeyon hajaaron varsh uparaant sarvaadhik ho jaaegi. san 1 se lekar 5383 tak, 4 karod kimi se kam ki 526 pahunch hai, fir lagbhag 60,158 varshon tak koi pahunch naheen hai.[74] sarvaadhik vikendrata ki avadhi ke dauraan, shukr kareeb se kareeb 3.82 karod kimi tak aa sakta hai.[3]

sauramandal ke sabhi grah soorya ki parikrama ek vaamaavart disha mein karte hai, jaisa ki soorya ke uttari dhruv ke upar se dekha gaya. adhikaansh grah apne aksh par bhi ek vaamaavart disha mein ghoomate hai, lekin shukr har 243 pruthvi divson mein ek baar dakshinaavart ( "pratigaami" ghoornan kaha jaata hai) ghoomta hai, yeh kisi bhi grah ki sarvaadhik dheemi ghoornan avadhi hai. is prakaar ek shukr naakshatr diwas ek shukr varsh (243 banaam 224.7 pruthvi diwas) se lambe samay tak rahata hai | shukr ki bhoomadhya rekha 6.5 kimi/ghanta ki gati se ghumati hai, jabki pruthvi ki bhoomadhya rekha par ghoornan lagbhag 1,670 kimi/ghanta hai.[75] shukr ka ghoornan 6.5 minute/shukr naakshatr diwas tak dheema ho gaya hai, jab se maigalan antariksh yaan ne 16 saal pehle usaka daura kiya hai |[76] pratigaami ghoornan ke kaaran, shukr par ek saur diwas ki lanbaai iske naakshatr diwas ki tulana mein kaafi kam hai, jo ki 116.75 pruthvi diwas hai (yeh shukr saur diwas ko budh ke 176 pruthvi divson ki tulana mein chhota banaata hai). shukr ka ek varsh lagbhag 1.92 shukr saur diwas lamba hai |[12] shukr ki dharati se ek prekshak ke liye, soorya pashchim mein udit aur poorv mein ast hoga.[12]

shukr grah, vibhinn ghoornan avadhi aur jhukaav ke saath ek saur neehaarika se gathit hua ho sakta hai. saghan vaayumandal par jvaareeya prabhaav aur graheeya udvignata dvaara prerit astavyast ghoornan badlaav ke kaaran vah vahaan se apni vartamaan sthiti tak pahuncha hai. yeh badlaav jo ki arabon varshon ki kriyaavidhi uparaant ghatit hua hoga. shukr ki ghoornan avadhi sambhavat: ek santulan ki avastha ko darshaati hai jo, soorya ke gurutvaakarshan ki or se jvaareeya jakadn jiski pravrutti ghoornan ko dheema karne ki hoti hai aur ghane shukr vaayumandal ke saur taapan dvaara banaai gayi ek vaayumandaleeya jvaar, ke madhya banti hai.[77][78] shukr ki kaksha aur usaki ghoornan avadhi ke beech ke 584-divseeya ausat antaraal ka ek rochak pahaloo yeh hai ki shukr ki pruthvi se uttarottar najadeeki pahunch kareeb-kareeb paanch shukr saur divso ke theek baraabar hai.[79] tathaapi, pruthvi ke saath ek ghoornan-kaksheeya anunaad ki parikalpana chhoot gayi hai.[80]

shukr ka koi praakrutik upagrah naheen hai,[81] haalaanki kshudragrah 2002 VE68 vartamaan mein iske saath ek ardh kaksheeya sambandh rakhata hai |[82][83] is ardh upagrah ke alaava, iske do anya asthaayi sah kaksheeya 2001 CK32 aur 2012 XE33 hai | 17 veen sadi mein giyovanni kaisini ne shukr ki parikrama kar rahe chandrama ki soochana di jo neith se naamit kiya gaya tha | agale 200 varshon ke uparaant anekon drashtavyon ki soochana di gayi | parantu adhikaansh ko aaspaas ke sitaaron ka hona nirdhaarit kiya gaya tha. California praudyogiki sansthaan mein, Alex elami va David steevensan ke poorv saur pranaali par 2006 ke modelon ke adhyayan bataate hai ki shukr ka hamaare jaisa kam se kam ek chaand tha jise arabo saal pehle ek badi takaraav ki ghatna ne banaaya tha.[84] adhyayan ke mutaabik kareeb ek karod saal baad ek anya takkar ne grah ki ghoornan disha ulat di. isne shukr ke chandrama ke ghumaav ya kaksha ko dheere dheere andar ki or sikudne ke liye prerit kiya jab tak ki vah shukr ke saath takaraakar usamein vileen naheen ho gaya.[85] yadi baad ki takkaron ne chandrama banaaye hai to vein bhi usi tarah se kheench liye gaye. upagrahon ke abhaav liye ek vaikalpik vyaakhya shaktishaali saur jvaar ka prabhaav hai jo bheetari sthaleeya grahon ki parikrama kar rahe bade upagrahon ko asthir kar sakte hai.[81]

paryavekshan

shukr ke charan aur iske spasht vyaas ka vikaas
A photograph of the night sky taken from the seashore. A glimmer of sunlight is on the horizon. There are many stars visible. Venus is at the center, much brighter than any of the stars, and its light can be seen reflected in the ocean.
shukr sada hamaare sauramandal se baahar ke sabse chamakeele taaron se bhi jyaada chamakadaar raha hai, jaisa prashaant mahaasaagar ke oopar yahaan dekha ja saka hai I

shukr kisi bhi taare (soorya ke alaava) ki tulana mein hamesha ujjaval hai. sarvaadhik kaantimaan, saapeksh kaantimaan −4.9,[9] arddhachandr charan ke dauraan hoti hai jab yeh pruthvi ke nikat hota hai. shukr kareeb −3 parimaan tak mand pad jaata hai jab yeh soorya dvaara chhupa liya jaata hai.[8] yeh grah dopahar ke saaf aasmaan me kaafi ujjaval dikhaai deta hai,[86] aur aasaani se dekha ja sakta hai jab soorya kshitij par neecha ho. ek avar grah ke roop mein, yeh hamesha soorya se lagbhag 47° ke bheetar hota hai.[10]

soorya ki parikrama karte hue shukr pratyek 584 divson par pruthvi ko paar kar jaata hai.[3] jaisa ki yeh dikhaai deta hai, yeh sooryaast ke baad "saanjh ka taara" se lekar sooryodaya se pehle "bhor ka taara" tak badal jaata hai. ek anya avar grah budh ka prasarakon maatr 28° ke adhiktam tak pahuainchata hai aur godhooli mein praay: mushkil se pahachaana jaata hai, jabki shukr ko apni adhiktam kaanti par chuk jaana kathin hai. iske adhik se adhik adhiktam prasarakon ka matlab hai yeh sooryaast ke ekdam baad tak andhere aasmaan mein najar aata hai. aakaash mein ek chamakadaar bindu sadrushya vastu ke rup mein shukr ko ek "agyaat udn tastari" maan lene ki sahaj galat bayaani hui hai. ameriki raashtrapati Jimmy Carter ne 1969 mein ek udn tastari dekhe jaane ki soochana di, jiske vishleshan ne baad mein grah hone ki sambhaavana ka sujhaav diya tha | anginat anya logon ne shukr ko asaadhaaran maanane ki bhool ki hai.[87]

jaise hi shukr ki apni kaksha ke irdagird halachal hoti hai, doorabeen drushyaavali mein yeh chandrama ki tarah kalaaon ka pradarshan karta hai: shukr ki kalaaon mein, grah ek chhoti si "poorn" chhavi prastut karta hai jab yeh soorya ke vipreet disha mein hota hai, jab yeh soorya se adhiktam kon par hota hai ek badi "chaturthaans kala" pradarshit karta hai, evam ratri aakaash mein apni adhiktam chamak par hota hai, tatha jaise hi yeh pruthvi aur soorya ke madhya sameepasth kaheen aaspaas aata hai doorabeen drushyaavali mein ek bahut bada "patala arddhachandr" prastut karta hai. shukr jab pruthvi aur soorya ke beechobeech hota hai, apne sabse bade aakaar par hota hai aur apni "nav kala" prastut karta hai. iske vaayumandal ko grah ke chaaron or ke apavartit prakaash ke prabhaamandal dvaara ek doorabeen mein dekha ja sakta hain.[10]

shukr paaragaman

shukr paaragaman, 2004

shukr ki kaksha pruthvi ki kaksha ke saapeksh thodi jhuki hui hai; isliye, jab yeh grah pruthvi aur soorya ke beech se gujarata hai, aamtaur par soorya ke mukhaakruti ko paar naheen karta. shukr paaragaman karna tab paaya jaata hai jab grah ka avar sanyojan pruthvi ke kaksheeya tal mein upasthiti ke saath mel khaata hai. shukr ke paaragaman 243 saal ke chakron mein hote hain | paaragaman ki vartamaan paddhati me, pehle do paaragaman aath varshon ke antaraal mein hote hai, fir kareeb 105.5 varsheeya ya 121.5 varsheeya lamba viraam aur fir se vaheen aath varsheeya antaraal ke nae paaragaman jodo ka daur shooroo hota hai. is svarup ko sabse pehle 1639 mein angrej khagolavid yirmayaah horoks ne khoja tha.[88]

naveenatam joda 8 June,2004 aur 5-6 June 2012 ko tha. paaragaman ka anekon online aautalets se seedhe athva uchit upakaran aur paristhitiyon ke saath sthaaneeya roop se dekha jaana ho saka.[89]

paaragaman ki poorvavarti jodi December 1874 aur December 1882 mein hui; aagaami jodi December 2117 aur December 2125 mein ghatit hogi.[90] aitihaasik rup se, shukr ke paaragaman mahatvapoorn the, kyonki unhone khagolavidon ko khagoleeya ikaai ke aakaar ke seedhe nirdhaaran karne ki anumati di hai, saath hi sauramandal ke aakaar ki bhi, jaisa ki 1639 mein horoks ke dvaara dekha gaya[91] captain cook ki Australia ki poorvi tat ki khoj tab sambhav ho pai jab vein shukr paaragaman ke prekshan ke liye peechha karte hue jalayaatra kar 1768 mein taahiti aa gaye.[92][93]

bhasmavarn prakaash

tathaakathit bhasmavarn prakaash lambe samay se chala aa raha shukr prekshanon ka ek rahasya hai. bhasmavarn prakaash shukr ke andhakaar paksh ki ek sukshm roshani hai aur najar aati hai jab grah arddh chandraakaar charan mein hota hai. is prakaash ko sarvapratham dekhne ka daava bahut pehle 1643 mein hua tha, parantu roshani ke astitv ki bharosemand pushti kabhi naheen ho pai. paryavekshakon ne anumaan lagaaya hai, yeh shukr ke vaayumandal mein bijli ki gatividhi se nikla parinaam ho sakta hai, lekin yeh bhraamak ho sakta hai. ho sakta hai yeh ek ujjval, arddh chandraakaar aakaar ki vastu dekhne ke bhram ka nateeja ho.[94]

adhyayan

poorv adhyayan

ek "black draap ifekt", jaisa ki 1769 ke paaragaman daramyaan darj kiya gaya.

shukr grah ko