Duniyar Dwarf

Duniyoyin Dwarf suna iya kasancewa masu aiki a fannin ilimin ƙasa, tsammanin da aka tabbatar a cikin shekarar ta 2015 ta hanyar aikin Dawn zuwa Ceres da aikin New Horizons zuwa Pluto. Saboda haka, masu ilimin ƙasa na duniya suna da sha'awar su musamman.

Masana ilimin taurari sun yarda da cewa aƙalla manyan 'yan takara tara sune ƙananan taurari - a cikin tsari na raguwar diamita, Pluto, Eris, Haumea, Makemake, Gonggong, Quaoar, Sedna, Ceres, da Orcus. Wani rashin tabbas ya kasance a kan dan takara na goma mafi girma Salacia, wanda za'a iya la'akari da shi a matsayin shari'ar iyaka. Daga cikin wadannan goma, biyu sun ziyarci jirgin sararin samaniya (Pluto da Ceres) kuma wasu bakwai suna da akalla wata daya da aka sani (Eris, Haumea, Makemake, Gonggong, Quaoar, Orcus, da Salacia), wanda ke ba da damar yawan su kuma ta haka ne a ƙayyade ƙididdigar yawan su. Mass da yawa a bi da bi za su iya dacewa da Tsarin geophysical a cikin ƙoƙari na ƙayyade yanayin waɗannan duniyoyi. Ɗaya kawai, Sedna, ba a ziyarta ba kuma ba shi da wata da aka sani, yana mai da ƙididdigar ƙididdigatattun nauyi da wuya. Wasu masu ilimin taurari sun haɗa da ƙananan abubuwa da yawa,  amma babu wata yarjejeniya cewa waɗannan na iya zama ƙananan taurari.

## Tarihin ra'ayin

Farawa a cikin 1801, masu binciken sararin samaniya sun gano Ceres da sauran abubuwa tsakanin Mars da Jupiter waɗanda aka ɗauka a matsayin taurari na shekaru da yawa. Tsakanin wannan lokacin da kuma kusa da 1851, lokacin da yawan taurari suka kai 23, masu binciken taurari sun fara amfani da kalmar Asteroid (daga Girkanci, ma'ana 'kamar tauraron' ko 'shaped-taurari') don ƙananan jiki kuma sun fara rarrabe su a matsayin *Ƙananan taurari* maimakon *Manyan taurari*.

Tare da gano Pluto a cikin 1930, yawancin masu binciken sararin samaniya sun yi la'akari da Tsarin Hasken rana don samun manyan taurari tara, tare da dubban ƙananan abubuwa (Asteroids da comets). Kusan shekaru 50, an yi tunanin Pluto ya fi Mercury girma,   amma tare da ganowa a 1978 na Wata na Pluto Charon, ya zama mai yiwuwa a auna nauyin Pluto daidai kuma a tantance cewa ya fi karami fiye da ƙididdigar farko.  Ya kasance kusan kashi ɗaya cikin ashirin na Mercury, wanda ya sanya Pluto mafi ƙanƙanta a duniya. Kodayake har yanzu yana da yawa fiye da sau goma kamar abu mafi girma a cikin belin asteroid, Ceres, yana da kashi ɗaya cikin biyar na nauyin Moon na Duniya. Bugu da ƙari, samun wasu halaye masu ban mamaki, kamar babban ƙarancin orbital da babban karkatawar orbital, ya zama bayyananne cewa wani nau'in jiki ne daban daga kowane ɗayan taurari.&nbsp;

A cikin shekarun 1990s, masu binciken sararin samaniya sun fara samun abubuwa a cikin wannan yankin sararin samaniya kamar Pluto (wanda yanzu ake kira Kuiper belt), kuma wasu ma da nisa. Da yawa daga cikin waɗannan sun raba wasu mahimman halaye na Pluto, kuma an fara ganin Pluto a matsayin mafi girma a cikin sabon nau'in abubuwa, plutinos. Ya bayyana cewa ko dai mafi girma daga cikin wadannan jikin dole ne a rarraba su a matsayin taurari, ko kuma dole ne a sake rarraba Pluto, kamar yadda aka sake rarraba Ceres bayan gano ƙarin asteroids. Wannan ya sa wasu masanan taurari su daina magana game da Pluto a matsayin duniyar. Kalmomi da yawa, gami da *subplanet* da *planetoid*, sun fara amfani da su don jikin da yanzu ake kira dwarf planets. Masana ilimin taurari sun kuma amince da cewa za a gano abubuwa da yawa kamar Pluto, kuma yawan taurari za su fara girma da sauri idan Pluto ya kasance an rarraba shi a matsayin duniyar.

Eris (wanda aka sani da 2003 UB313), wani abu ne na trans-Neptunian, an gano shi a watan Janairun shekara ta 2005;  an yi tunanin ya fi Pluto girma, kuma wasu rahotanni sun kira shi a matsayin duniyar goma.  A sakamakon haka, batun ya zama batun muhawara mai tsanani a lokacin Babban Taron IAU a watan Agustan shekara ta 2006. Shirin farko na IAU ya haɗa da Charon, Eris, da Ceres a cikin jerin taurari. Bayan da masanan taurari da yawa suka ki amincewa da wannan shawarar, masanan tauraron dan adam na Uruguay Julio Ángel Fernández da Gonzalo Tancredi sun tsara wani zaɓi: Sun ba da shawarar wani rukuni na tsakiya don abubuwa masu girma don zama zagaye amma hakan bai share hanyoyin su na planetesimals ba. Baya ga sauke Charon daga jerin, sabon tayin ya kuma cire Pluto, Ceres, da Eris, saboda ba su share hanyoyin su ba.

Kodayake an nuna damuwa game da rarraba taurari da ke kewaye da wasu taurari,  ba a warware batun ba; an ba da shawarar a maimakon haka don yanke shawarar wannan ne kawai lokacin da aka fara lura da abubuwa masu girman duniya. 

Nan da nan bayan ma'anar IAU na dwarf planet, wasu masana kimiyya sun nuna rashin jituwa da ƙudurin IAU. Kamfen ɗin sun haɗa da takalma na bumper mota da T-shirts. Mike Brown (wanda ya gano Eris) ya yarda da rage yawan taurari zuwa takwas.

NASA ta sanar a shekara ta 2006 cewa za ta yi amfani da sabbin jagororin da IAU ta kafa. Alan Stern, darektan aikin NASA zuwa Pluto, ya ki amincewa da ma'anar IAU ta yanzu game da duniyar, duka dangane da bayyana taurari masu ƙanƙanta a matsayin wani abu banda wani nau'in duniyar, da kuma amfani da halaye na orbital (maimakon halaye na ainihi) na abubuwa don bayyana su a matsayin taurari masu ƙananan. Don haka, a cikin 2011, har yanzu yana magana game da Pluto a matsayin duniyar,  kuma ya yarda da wasu taurari masu yiwuwa kamar Ceres da Eris, da kuma manyan watanni, a matsayin ƙarin taurari.  Shekaru da yawa kafin ma'anar IAU, ya yi amfani da halaye na orbital don raba "überplanets" (mafi rinjaye takwas) daga "counterplanets" ("ƙananan taurari"), la'akari da nau'ikan "duniya".

## Sunan

Sunayen manyan jikin duniya sun haɗa da dwarf planet, *planetoid* (mafi yawan lokaci), meso-planet (wanda aka yi amfani da shi don girman tsakanin Mercury da Ceres), kusan-planet, da (a yankin transneptunian) *plutoid*. *Duniyar Dwarf*, duk da haka, an samo asali ne a matsayin kalma don ƙananan taurari, ba manyan taurari ba, kuma har yanzu masu binciken taurari da yawa suna amfani da ita ta wannan hanyar.

Kalmar dwarf planet, wacce aka yi amfani da ita azaman ma'anar *Asteroid,* ta samo asali ne daga akalla zuwa 1838. An kuma yi amfani da shi azaman antonym ga *babbar ,*, gami da taurari na duniya Mercury, Venus, Duniya, da Mars, da kuma Wata. A cikin tsarin su na shekara ta 2006, IAU ta yanke shawarar cewa ba za a dauki taurari masu ƙanƙanta a matsayin taurari ba. Sauran sharuɗɗa don ma'anar IAU na manyan jikin da ba su da irin wannan rikice-rikice ko amfani sun haɗa da kusan-duniya  da tsohuwar kalmar *planetoid* ("suna da siffar duniyar").  Michael E. Brown ya bayyana cewa *planetoid* "kalma ce mai kyau" wacce aka yi amfani da ita ga waɗannan jikin shekaru da yawa, kuma amfani da kalmar dwarf planet don wanda ba duniyar ba "mafi hankali" ce, amma an motsa shi ta hanyar yunkurin da IAU Division III ya yi don sake dawo da Pluto a matsayin duniyar a cikin ƙuduri na biyu. Lalle ne, daftarin Resolution 5A ya kira waɗannan matsakaitan jikin planetoids, amma zaman majalisa ya kada kuri'a tare don canza sunan zuwa dwarf planet. Ƙuduri na biyu, 5B, ya bayyana taurari masu ƙanƙanta a matsayin nau'in duniyar, kamar yadda Stern ya yi niyya da farko, ya bambanta da sauran takwas da za a kira "duniyoyin gargajiya". A karkashin wannan tsari, za a adana taurari goma sha biyu na shawarar da aka ƙi a cikin bambanci tsakanin taurari takwas na gargajiya da taurari huɗu. An kayar da ƙuduri na 5B a wannan zaman da aka zartar da 5A. Saboda rashin daidaituwa na *****karamin duniya*.**','' da ba ta zama duniyar ba saboda gazawar Resolution 5B, an tattauna wasu kalmomi kamar ''Nanoplanet'' da ''subplanet'', amma babu wata yarjejeniya tsakanin CSBN don canza shi.

A cikin mafi yawan harsuna an halicci kalmomin daidai ta hanyar fassara dwarf planet mafi-ko-ƙasa a zahiri: Faransanci dwarf planet, Mutanen Espanya dwarf planet. Jamusanci **', Rasha karlikovaya planet (karlic planet), Larabci *kaukab qazm* (), Sinanci ǎixíngxīng (), Koriya *waesohangseong* (Wesohangsoong) ko *waehangseong* (Yancianciancianci (Wasi성 /矮行星), amma a cikin Jafananci suna kiran su jun-duni" (koka-duni). [ana buƙatar ƙa'ida]&#x5B;**'&#x5D;</sup>

IAU Resolution 6a na 2006  ya amince da Pluto a matsayin "ainihin sabon rukuni na abubuwa na trans-Neptunian". Ba a ƙayyade sunan da ainihin yanayin wannan rukunin ba amma an bar su ga IAU don kafawa a kwanan wata; a cikin muhawara da ta kai ga ƙudurin, an kira membobin rukunin daban-daban a matsayin **'pluton**' da abubuwa na plutonian amma ba a ci gaba da sunan ba, watakila saboda ƙin yarda daga masu ilimin ƙasa cewa wannan zai haifar da rikicewa tare da pluton din su.

A ranar 11 ga Yuni, 2008, Kwamitin Zartarwa na IAU ya ba da sanarwar sabon lokaci, ''plutoid'', da ma'anar: duk taurari masu karami na trans-Neptunian sune plutoids. Sauran sassan IAU sun ki amincewa da kalmar:
 

Rukunin 'plutoid' ya kama bambancin da ya gabata tsakanin 'dwargwadon duniya' Ceres da 'dwarbannin kankara' na tsarin hasken rana na waje,  wani ɓangare na ra'ayi na rabuwa uku na tsarin haskyar rana a cikin taurari na ciki, ''manyan taurari'' na [[Comet]]_nucleus" id="mwAWo" rel="mw:WikiLink" title="Comet nucleus">tsakiya, da ƙananan kankara na waje, wanda Pluto shine babban memba.  'Ice dwarf' kuma ya ga wasu amfani a matsayin laima ga duk Ƙananan taurari na trans-Neptunian, ko ga Asteroids na kankara na tsarin hasken rana na waje; daya daga cikin ƙoƙarin bayyanawa shine cewa ''dwarfs na kankara'' "ya fi girma fiye da tsakiya na comet na al'ada kuma a nan fiye da asteroid".

Tun lokacin da aka yi aikin Dawn, an gane cewa Ceres wani abu ne mai sanyi wanda zai iya samo asali ne daga tsarin hasken rana na waje. Ceres tun daga lokacin ana kiranta karamin kankara.

== Ka'idoji ==

Dynamicists yawanci sun fi son yin amfani da rinjaye mai nauyi a matsayin ƙofar planethood, saboda daga hangen nesa ƙananan jikin su sun fi dacewa da makwabtansu, misali Ceres a matsayin babban asteroid kuma Pluto a matsayin babban abu na Kuiper. Masana kimiyyar ƙasa yawanci sun fi son zagaye a matsayin ƙofar, saboda daga hangen nesa ilimin ƙasa na jiki kamar Ceres ya sa ya fi kama da duniyar gargajiya kamar Mars, fiye da ƙaramin asteroid wanda ba shi da ilimin ƙasa na ciki. Wannan ya bukaci kirkirar rukunin taurari masu ƙanƙanta don bayyana wannan aji na tsakiya.

=== Gudanar da sararin samaniya ===
<div class="pie-thumb thumb tright"><div class="thumbinner"><div class="smooth-pie-container" style=""><div class="smooth-pie-legend-container"><div class="smooth-pie-caption">Nauyin kwatankwacin taurari masu ƙanƙanta, tare da [[Charon (moon)|Charon]] don kwatanta.</div>

# <span class="l-label">Eris 16.6</span>
# <span class="l-label">Pluto 13.03</span>
# <span class="l-label">Haumea 4.01</span>
# <span class="l-label">Ka yi amfani da shi 3.1</span>
# <span class="l-label">Gonggong 1.75</span>
# <span class="l-label">Charon 1.59</span>
# <span class="l-label">Quaoar 1.4</span>
# <span class="l-label">Ceres 0.94</span>
# <span class="l-label">Orcus 0.61</span>
# <span class="l-label">Salacia 0.492</span>

<div class="smooth-pie-footer">Rukunin taro shine <span style="margin:0 .15em 0 .25em">×</span> kg. [[Eris (dwarf planet)|Eris]] da Pluto sun mamaye. An cire [[90377 Sedna|Sedna]] mara ma'auni, amma mai yiwuwa ne a kan umarnin Ceres. Wata da bambanci shine 73.5×10<sup><span class="nowrap"><sup><span class="nowrap">21</span></sup></span></sup> kg, sama da sau hudu fiye da Eris.</div></div><div aria-hidden="true" class="smooth-pie" style="width:250px;height:250px;background:#888;color:#000;-webkit-print-color-adjust: exact; print-color-adjust: exact;"><div class="pie25" style="background:#1b7837;color:#000" title="Eris 16.6"></div><div class="pie25" style="background:#1b7837;color:#000; transform: rotate(0.1334163turn)" title="Eris 16.6"></div><div class="pie25" style="background:#7fbf7b;color:#000; transform: rotate(0.3804163turn)" title="Pluto 13.03"></div><div class="pie25" style="background:#7fbf7b;color:#000; transform: rotate(0.4318051turn)" title="Pluto 13.03"></div><div class="pie7" style="background:#d9f0d3;color:#000; transform: rotate(0.6807051turn)" title="Haumea 4.01"></div><div class="pie7" style="background:#d9f0d3;color:#000; transform: rotate(0.7030424turn)" title="Haumea 4.01"></div><div class="pie7" style="background:#762a83;color:#000; transform: rotate(0.7728424turn)" title="Makemake 3.1"></div><div class="pie7" style="background:#762a83;color:#000; transform: rotate(0.7742708turn)" title="Makemake 3.1"></div><div style="transform: rotate(0.8440708turn); background:#af8dc3;color:#000; clip-path: polygon(0% 0%, 25.67563604% 0%, 0 100%)" title="Gonggong 1.75"></div><div style="transform: rotate(0.8842803turn); background:#e7d4e8;color:#000; clip-path: polygon(0% 0%, 23.67585852% 0%, 0 100%)" title="Charon 1.59"></div><div style="transform: rotate(0.9208136turn); background:#d73027;color:#000; clip-path: polygon(0% 0%, 20.38158399% 0%, 0 100%)" title="Quaoar 1.4"></div><div style="transform: rotate(0.9529812turn); background:#fc8d59;color:#000; clip-path: polygon(0% 0%, 13.91172711% 0%, 0 100%)" title="Ceres 0.94"></div><div style="transform: rotate(0.9745795turn); background:#fee090;color:#000; clip-path: polygon(0% 0%, 8.81921820% 0%, 0 100%)" title="Orcus 0.61"></div><div style="transform: rotate(0.9885954turn); background:#fff;color:#000; clip-path: polygon(0% 0%, 6.92253007% 0%, 0 100%)" title="Salacia 0.492"></div><div class="smooth-pie-border"></div></div></div></div></div>Alan Stern da Harold F. Levison sun gabatar da ma'auni Λ ( babban case lambda ) a cikin 2000, yana bayyana yuwuwar haduwar da ke haifar da karkatar da sararin samaniya.[1] Darajar wannan siga a cikin samfurin Stern yayi daidai da murabba'in taro kuma sabanin lokacin. Ana iya amfani da wannan ƙimar don ƙididdige ƙarfin jiki don share unguwar da ke kewaye da shi, inda Λ > 1 zai share ta. An sami rata na umarni biyar na girma a cikin Λ tsakanin mafi ƙanƙantar taurarin duniya da mafi girma asteroids da abubuwan bel na Kuiper.[2]

Yin amfani da wannan siginar, Steven Soter da sauran masu binciken sararin samaniya sun yi jayayya game da bambancin tsakanin taurari da ƙananan taurari bisa ga rashin iyawar ƙarshen don "bayyana makwabta a kusa da hanyoyin su": taurari suna iya cire ƙananan abubuwa kusa da hanyoyinsu ta hanyar haɗuwa, kamawa, ko rikice-rikice na nauyi (ko kafa tasirin da ke hana haɗuwa), yayin da ƙananan tauraron ba su da nauyin yin hakan. Soter ya ci gaba da ba da shawarar wani siginar da ya kira mai ''nuna bambanci na duniya'', wanda aka sanya tare da alamar μ (mu), wanda ke wakiltar ma'auni na gwaji na ainihin matakin tsabta na yankin orbital (inda aka lissafa μ ta hanyar raba nauyin jikin dan takarar ta jimlar nauyin sauran abubuwa da ke raba yankin orbital), inda aka ɗauka μ > 100 za a share shi.

Jean-Luc Margot ya inganta ra'ayin Stern da Levison don samar da irin wannan fasalin Π (babban shari'ar Pi).  Ya dogara ne akan ka'idar, kauce wa bayanan da Λ ta yi amfani da su.  yana nuna duniyar, kuma akwai gibin da yawa tsakanin taurari da ƙananan taurari.

Akwai wasu tsare-tsare da yawa waɗanda ke ƙoƙarin rarrabe tsakanin taurari da ƙananan taurari,  amma ma'anar 2006 tana amfani da wannan ra'ayi. 

=== Daidaitawar ruwa ===
Isasshen matsin lamba na ciki, wanda ya haifar da ƙarfin maganaɗiso na jiki, zai juya filastik na jiki, kuma isasshen filastik zai ba da damar tsaunuka masu tsawo su nutse kuma ramuka su cika, tsarin da aka sani da shakatawa na nauyi. Jikin da suka fi 'yan kilomita suna mamaye dakarun da ba na jan hankali ba kuma suna da siffar da ba ta dace ba kuma suna iya zama tarin tarkace. Abubuwa mafi girma, inda nauyi yake da mahimmanci amma ba ya rinjaye, suna da siffar dankali; mafi girman jiki, mafi girman matsin lamba na ciki, mafi ƙarfi yana da kuma siffarsa, har sai matsin ya isa ya shawo kan ƙarfin ƙarfinsa kuma ya sami daidaitattun hydrostatic. Sa'an nan kuma, jiki yana da zagaye kamar yadda zai yiwu, saboda juyawa da tasirin ruwa, kuma yana da siffar ellipsoid. Wannan shine iyakar iyakar duniyar karami.

Idan wani abu yana cikin daidaitattun ruwa, wani nau'i na ruwa na duniya a samansa zai samar da wani nau'in iri ɗaya da jiki, ban da ƙananan siffofi na saman kamar craters da fissures. Jikin zai sami siffar ƙwallo idan ba ya juyawa kuma yana da siffar ellipsoidal idan ya yi. Da sauri yake juyawa, ya fi tsayi ko ma scalene ya zama. Idan irin wannan jiki mai juyawa ya yi zafi har sai ya narke, siffarsa ba za ta canza ba. Misali mai tsanani na jiki wanda zai iya zama scalene saboda saurin juyawa shine Haumea, wanda yake sau biyu a kan babban axis kamar yadda yake a kan sanduna. Idan jiki yana da babban aboki na kusa, to, dakarun ruwa a hankali suna jinkirta juyawa har sai an kulle shi; wato, koyaushe yana gabatar da fuska ɗaya ga abokinsa. Jikin da aka kulle a cikin ruwa ma suna da scalene, kodayake wani lokacin kadan ne kawai. [[Wata]] ta Duniya tana kulle, kamar yadda duk tauraron dan adam na manyan iskar gas suke. Pluto da Charon suna kulle juna, kamar yadda Eris da Dysnomia, kuma mai yiwuwa ma Orcus da Vanth. [ana buƙatar ƙa'ida]<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">&#x5B;**'&#x5D;

IAU takamaiman girman ko iyakar taro na taurari masu ƙanƙanta, saboda waɗannan ba su bayyana siffofi ba. Babu iyaka mai zurfi: wani abu da ke da nisa a cikin Tsarin Hasken rana wanda ya fi girma fiye da Mercury bazai sami lokaci don share makwabtanta ba, kuma irin wannan jiki zai dace da ma'anar duniyar dwarf maimakon duniyar. Lalle ne, Mike Brown ya fara neman irin wannan abu. Ƙananan iyaka an ƙayyade ta hanyar buƙatun cimma da riƙe daidaitattun hydrostatic, amma girman ko taro wanda abu ya kai kuma ya riƙe daidaituwa ya dogara da abun da ke ciki da tarihin zafi, ba kawai nauyinsa ba.  Sashe na tambaya da amsar ya kiyasta cewa abubuwa da ke da taro sama da 0.5×10 kg da radius sama da 400 km za su kasance a "al'ada" a cikin daidaitattun ruwa (shapin ... zai ƙayyade shi ta hanyar lura da kai-gravity), amma duk lokuta na iyaka za a ƙayyade su ƙayyade don ƙaddara su Wannan yana kusa da abin da ya zuwa 2019 aka yi imanin cewa kusan iyaka ne ga abubuwa da suka wuce Neptune waɗanda ke da cikakkiyar kamfani, jiki mai ƙarfi, tare da Salacia (r = 423±11 km , m = (0.492±0.007) ×1021 kg) kasancewa layin iyaka duka don tsammanin Q & A na 2006 da kuma a cikin ƙididdigar kwanan nan, kuma tare da Orcus yana sama da iyakar da ake tsammani. Babu wani jiki da aka auna taro kusa da iyakar taro da ake tsammani, kodayake da yawa ba tare da auna taro ba suna kusantar iyakar girman da ake tsammami. [ana buƙatar ƙa'ida]&#x5B;**'&#x5D;</sup>

== Yawan taurari masu ƙanƙanta ==
 

Kodayake ma'anar duniyar karami a bayyane take, shaidar game da ko wani abu na trans-Neptunian da aka ba shi girma ne kuma mai iya daidaitawa don a tsara shi ta hanyar filin sa na nauyi sau da yawa ba a kammala shi ba. Har ila yau, akwai tambayoyi masu ban sha'awa game da fassarar ma'aunin IAU a wasu lokuta. Sakamakon haka yawan TNOs da aka daidaita a halin yanzu wanda ya hadu da ma'auni na daidaitaccen ruwa ba shi da tabbas.

Abubuwa uku da ake la'akari da su a lokacin muhawara da ta kai ga karɓar IAU na 2006 na rukunin dwarf planet - Ceres, Pluto da Eris - ana karɓar su gabaɗaya a matsayin dwarf planetes, gami da waɗancan masu binciken taurari waɗanda ke ci gaba da rarraba dwarf planets a matsayin taurari. Ɗaya daga cikinsu - Pluto - an lura da shi dalla-dalla don tabbatar da cewa siffarsa ta yanzu ta dace da abin da za a sa ran daga daidaitattun hydrostatic. Ceres yana kusa da daidaituwa, amma wasu anomalies na gravitational sun kasance ba a bayyana su ba. Ana zaton Eris gabaɗaya ƙaramar duniyar ce saboda ta fi Pluto girma.

# Ceres - an gano shi a ranar 1 ga Janairu, 1801, kuma an sanar da Janairu 24, shekaru 45 kafin [[Neptune]]. An yi la'akari da duniyar har tsawon rabin karni kafin sake rarraba shi a matsayin asteroid. IAU ta yi la'akari da karamin duniyar tun lokacin da aka amince da Resolution 5A a ranar 24 ga watan Agusta, 2006.
# Pluto - an gano shi a ranar 18 ga Fabrairu, 1930, kuma an sanar da shi a ranar 13 ga Maris. An yi la'akari da duniyar shekaru 76. An sake rarraba shi a bayyane a matsayin karamin duniyar ta IAU tare da Resolution 6A a ranar 24 ga watan Agusta, 2006.  Wata biyar da aka sani.
# Eris (2003 UB313) - an gano shi a ranar 5 ga Janairu, 2005, kuma an sanar da shi a ranar 29 ga Yuli. An kira shi "[[Planets beyond Neptune|Duniyar ta goma]]" a cikin rahotanni na kafofin watsa labarai. IAU ta yi la'akari da karamin duniyar tun lokacin da aka amince da Resolution 5A a ranar 24 ga watan Agusta, 2006, kuma kwamitin suna na karamin duniyar IAU ya sanya masa suna a ranar 13 ga watan Satumba na wannan shekarar. Wata daya da aka sani. 
Al'ummar taurari galibi suna nufin wasu manyan TNOs a matsayin ƙananan taurari. Akalla ƙarin jiki huɗu sun cika ka'idojin farko na Brown, na Tancredi et al., na Grundy et al., da na Emery et al. don gano taurari masu ƙanƙanta, kuma yawanci ana kiransu taurari masu yawa ta hanyar masu binciken taurari:
 
Misali, JPL / NASA da ake kira Gonggong, duniyar karami bayan lura a cikin 2016,  da Simon Porter na Cibiyar Bincike ta Kudu maso Yamma ya yi magana game da "manyan taurari takwas [TNO] karami" a cikin 2018, yana nufin Pluto, Eris, Haumea, Makemake, Gonggong, Quaoar, Sedna da Orcus.  IAU kanta ta kira Quaoar karamin duniyar a cikin rahoton shekara-shekara na 2022-2023.

An gabatar da ƙarin jikin, kamar Salacia da Máni ta Brown; Varuna da Ixion ta Tancredi da sauransu, da Chiminigagua ta Sheppard da sauransu. Yawancin manyan jikin suna da watannin, wanda ke ba da damar ƙaddamar da nauyin su kuma ta haka ne yawan su, wanda ke sanar da kimantawa game da ko za su iya zama ƙananan taurari. Mafi girma TNOs da ba a san su da wata ba sune Sedna, Máni, Aya, da Ixion. Musamman, Salacia yana da sanannen taro da diamita, yana sanya shi a matsayin shari'ar iyaka ta IAU ta 2006 Q&A. [ana buƙatar ƙa'ida]<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">&#x5B;**'&#x5D;A lokacin da aka ambaci sunan Makemake da Haumea, an yi tunanin cewa abubuwa na trans-Neptunian (TNOs) tare da ƙwayoyin ƙanƙara za su buƙaci diamita kusan kilomita 400 (250 mi), ko 3% girman Duniya - girman watanni Mimas, ƙaramin wata wanda ke zagaye, da Proteus, mafi girma wanda ba - don shakatawa cikin daidaituwa na nauyi. Masu bincike sun yi tunanin cewa yawan irin waɗannan jikin zasu iya zama kusan 200 a cikin Kuiper belt, tare da dubban da suka wuce.   Wannan yana daya daga cikin dalilan (ci gaba da jerin 'duniyoyin' zuwa adadi mai ma'ana) cewa an sake rarraba Pluto da farko. Bincike tun daga wannan lokacin ya sanya shakku game da ra'ayin cewa ƙananan jikin zasu iya cimma ko kiyaye daidaito a ƙarƙashin yanayin da ke cikin belin Kuiper da bayan. [ana buƙatar ƙa'ida]&#x5B;**'&#x5D;</sup>

Kowane masanin taurari ya gane abubuwa da yawa a matsayin ƙananan taurari ko kuma yiwuwar tabbatar da cewa ƙananan taurari ne. A cikin 2008, Tancredi et al. sun shawarci IAU da su yarda da Orcus, Sedna da Quaoar a matsayin taurari masu ƙanƙanta (ba a san Gonggong ba tukuna), kodAya IAU ba ta magance batun ba a lokacin kuma ba ta da tun daga lokacin. Tancredi ya kuma yi la'akari da TNOs guda biyar Varuna, Ixion, Achlys, 2004 GV9, da Aya a matsayin yiwuwar su zama taurari masu ƙanƙanta. Tun daga shekara ta 2011, Brown ya ci gaba da jerin daruruwan abubuwa masu takara, daga "kusan tabbas" zuwa "mai yiwuwa" taurari masu ƙanƙanta, bisa ga ƙididdigar girman kawai. Ya zuwa ranar 13 ga Satumba, 2019, jerin Brown sun gano abubuwa goma na trans-Neptunian tare da diamita sannan ana zaton sun fi 900 km (wanda IAU ta kira hudu tare da Gonggong, Quaoar, Sedna, Orcus, Máni, da Salacia) a matsayin "kusan tabbas" don zama dwarf planetes, da kuma wani 16, tare da diamitar fiye da 600 km, kamar yadda "mai yiwuwa". Musamman, Gonggong na iya samun diamita mafi girma (1230±50 km) fiye da wata mai zagaye na Pluto Charon (1212 km).

Amma a cikin 2019 Grundy et al. sun ba da shawarar, bisa ga binciken da suka yi game da Gī'hòmdímà, cewa duhu, ƙananan abubuwa da suka fi kusan 900-1000 km a diamita, kamar Salacia da Varda, ba su taɓa rushewa cikin abubuwa masu ƙarfi na duniya ba kuma suna riƙe da ƙuƙwalwar ciki daga kafawarsu (inda ba za su iya zama ƙananan taurari ba). Sun yarda cewa mafi haske (albedo > ≈0.2)  ko mafi yawa (> ≈1.4 g /cc) Orcus da Quaoar tabbas sun kasance cikakke: 

Daga baya aka gano Salacia yana da ɗan yawa, wanda za'a iya kwatanta shi da na Orcus, kodayake har yanzu yana da duhu sosai. Duk da wannan ƙuduri, Grundy et al. suna kiranta "girman tauraron dwarf", yayin da suke kiran Orcus duniyar dwarf. Bincike na baya a kan Varda ya nuna cewa yawanta na iya zama babba, kodayake ba za a iya cire ƙananan yawa ba.

A cikin <sub>2</sub>, Emery et al. sun rubuta cewa spectroscopy na kusa da infrared ta hanyar James Webb Space Telescope (JWST) a cikin 2022 ya nuna cewa Sedna, Gonggong, da Quaoar sun sami narkewar ciki, bambanci, da juyin halitta na sinadarai, kamar manyan taurari masu suna Pluto, Eris, Haumea, da Makemake, amma ba kamar "duk ƙananan KBOs ba". Wannan shi ne saboda hydrocarbons masu haske suna nan a saman su (misali ethane, acetylene, da ethylene), wanda ke nuna cewa ana ci gaba da sake samar da methane, kuma methane zai iya fitowa daga geochemistry na ciki. A gefe guda, saman Sedna, Gonggong, da Quaoar suna da ƙananan CO da CO2, kama da Pluto, Eris, da Makemake, amma ya bambanta da ƙananan jiki. Wannan yana nuna cewa ƙofar dwarf planethood a cikin yankin trans-Neptunian yana da diamita na ~900 km (don haka ya haɗa da Pluto, Eris, Haumea, Makemake, Gonggong, Quaoar, Orcus, da Sedna), kuma har ma Salacia bazai zama dwarf planet ba. Binciken 2023 na Máni ya nuna cewa mai yiwuwa yana da babban rami, wanda zurfinsa ya kai kashi 5.7% na diamita: wannan ya fi girma fiye da rami na Rheasilvia a kan Vesta, wanda shine dalilin da ya sa ba a yawan la'akari da Vesta a yau.

A cikin 2024, Kiss et al. sun gano cewa Quaoar yana da siffar ellipsoidal wanda bai dace da daidaitattun hydrostatic ba don juyawa na yanzu. Sun yi zaton cewa Quaoar da farko yana da saurin juyawa kuma yana cikin daidaitattun ruwa, amma siffarsa ta zama "tsuntsu a ciki" kuma ba ta canza ba yayin da ta juya ƙasa saboda ƙarfin ruwa daga wata Weywot. Idan haka ne, wannan zai yi kama da halin da ake ciki na wata na Saturn Iapetus, wanda ya yi yawa don juyawa na yanzu. Iapetus gabaɗaya har yanzu ana ɗaukarsa wata ce mai yawan duniya duk da haka,  ko da yake ba koyaushe ba.

=== Duniyoyin da suka fi dacewa ===


Abubuwan trans-Neptunian a cikin tebur masu zuwa, ban da Salacia, Brown, Tancredi et al., Grundy et al., da Emery et al. sun amince da su don zama yiwuwar dwarf planetes, ko kusa da shi. An haɗa Salacia a matsayin mafi girma TNO wanda ba a yarda da shi ba a matsayin karamin duniyar; jiki ne mai iyaka ta hanyar ka'idoji da yawa, sabili da haka an yi amfani da shi. Charon, wata na Pluto wanda IAU ta gabatar a matsayin karamin duniyar a cikin shekara ta 2006, an haɗa shi don kwatanta. Wadannan abubuwa da ke da cikakkiyar girman da ya fi +1, don haka sun hadu da ƙofar kwamitin suna na duniya-ƙananan duniya na IAU, an nuna su, kamar yadda Ceres, wanda IAU ta ɗauka cewa duniya ce mai ƙanƙanta tun lokacin da suka fara muhawara game da manufar.

An lissafa yawan taurari masu ƙanƙanta don tsarin su (idan suna da tauraron dan adam) ban da Pluto da Orcus.



=== Alamomi ===
Ceres  da Pluto  sun sami Alamomin duniya, saboda an dauke su taurari lokacin da aka gano su. A lokacin da aka gano sauran, alamomin duniya galibi sun ɓace daga amfani tsakanin masu binciken sararin samaniya. Unicode ya haɗa da alamomi don Quaoar , Sedna , Orcus , Haumea , Eris , Makemake , da Gonggong , waɗanda masu ilimin taurari ke amfani da su da farko: Denis Moskowitz, injiniyan software a Massachusetts ne ya tsara su. NASA ta yi amfani da alamomin Haumea, Eris, da Makemake, da kuma alamar tauraron gargajiya ga Pluto  lokacin da take magana game da shi a matsayin karamin duniyar.  Alamomin ƙananan abubuwa ba su da tabbas; wani tsari na Unicode ya lura da alamar Moskowitz don Salacia. Moskowitz ya kuma tsara alama ga Charon . 

== Bincike ==

Ya zuwa 2025, manufofi biyu ne kawai suka yi niyya kuma suka binciki taurari masu ƙanƙanta a kusa. A ranar 6 ga Maris, 2015, jirgin sararin samaniya na Dawn ya shiga orbit a kusa da Ceres, ya zama jirgin sararin sama na farko da ya ziyarci duniyar dwarf. A ranar 14 ga watan Yulin shekara ta 2015, binciken sararin samaniya na New Horizons ya tashi ta [[Pluto]] da watanni biyar.

Ceres yana nuna irin wannan shaidar ilimin ƙasa mai aiki kamar ajiyar gishiri da cryovolcanos, yayin da Pluto yana da tsaunuka masu kankara da ke gudana a cikin ƙanƙarar nitrogen, da kuma yanayi mai mahimmanci. Ceres a bayyane yake yana da saline percolating ta hanyar ƙasa, yayin da akwai shaidar cewa Pluto yana da ainihin teku mai zurfi. [ana buƙatar ƙa'ida]<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">&#x5B;**'&#x5D;

Dawn a baya ta kewaye asteroid Vesta. Cassini ya zana hoton wata ta Saturn Phoebe kuma kafin haka ta Voyager 2, wanda kuma ya haɗu da wata ta Neptune Triton. Dukkanin jikin uku suna nuna shaidar cewa sun kasance taurari masu ƙanƙanta, kuma binciken su yana taimakawa wajen bayyana juyin halitta na taurari masu ƙarami. [ana buƙatar ƙa'ida]&#x5B;**'&#x5D;</sup>

New Horizons ya kama hotuna masu nisa na Triton, Quaoar, Haumea, Eris, da Makemake, da kuma ƙananan 'yan takara Ixion, Máni, da 2014 OE394.  An gabatar da Quaoar a matsayin mai yuwuwar tashi ta hanyar binciken ''Shensuo'' guda biyu na Hukumar Kula da sararin samaniya ta kasar Sin.

== Irin waɗannan abubuwa ==
Yawancin jikin suna kama da ƙananan taurari. Wadannan sun hada da tsoffin taurari masu ƙanƙanta, wanda har yanzu yana da siffar daidaitawa ko shaidar ilimin ƙasa mai aiki; watannin duniya, waɗanda suka haɗu da ma'anar jiki amma ba ma'anar orbital don duniyar ƙanƙara ba; da Charon a cikin tsarin Pluto-Charon, wanda tabbas shine duniyar ƙanshin binary. Wadannan rukuni na iya haɗuwa: Triton, alal misali, tsohuwar duniyar dwarf ce da wata mai yawan duniya. [ana buƙatar ƙa'ida]<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">&#x5B;**'&#x5D;

### Tsoffin dwarf planetes

Vesta, jiki mafi girma na gaba a cikin belin asteroid bayan Ceres, ya kasance a cikin daidaitattun ruwa kuma yana da kusan spheroidal, yana karkatar da shi saboda tasirin da ya haifar da craters na Rheasilvia da Veneneia bayan ya karfafa. Girmansa bai dace da shi a halin yanzu yana cikin daidaitattun ruwa ba. Triton ya fi girma fiye da Eris ko Pluto, yana da siffar daidaitawa, kuma ana zaton yana da duniyar dwarf da aka kama (watakila memba ne na tsarin binary), amma ba ya kewaye da rana kai tsaye. Phoebe ce da aka kama wacce, kamar Vesta, ba ta cikin daidaitattun ruwa, amma ana zaton ta kasance da wuri a tarihinta saboda zafi na radiogenic.

### Watanni masu yawa
Akalla watanni goma sha tara suna da siffofin daidaito daga sun rushe cikin jiki mai ƙarfi (ko a wasu lokuta cikin kusan jiki mai ƙarfi) ko ma sun shakatawa a ƙarƙashin ƙarfin kai a wani lokaci, kodayake wasu daga cikin waɗannan sun daskare kuma ba su cikin daidaito ba. Bakwai sun fi girma fiye da ko dai Eris ko Pluto. Wadannan manyan watanni ba su da bambanci daga ƙananan taurari, amma ba su dace da ma'anar IAU ba saboda ba sa kewaye da Rana kai tsaye.  (Hakika, wata na Neptune Triton duniyar dwarf ce da aka kama, kuma Ceres ta samo asali ne a wannan yankin na Tsarin Hasken rana kamar watannin Jupiter da Saturn.) Alan Stern ya kira watannin duniya "Duniyoyin tauraron dan adam", ɗaya daga cikin nau'ikan tauraron dan kasa guda uku, tare da tauraron dwarf da taurari na gargajiya. Kalmar planemo ("abu na duniya") kuma ya rufe dukkan al'ummomi uku.

#### Charon
An yi muhawara game da ko ya kamata a dauki tsarin Pluto-Charon a matsayin duniyar dwarf biyu. A cikin ƙuduri na IAU game da ma'anar duniya, an yi la'akari da Pluto da Charon a matsayin taurari a cikin tsarin binary.  IAU a halin yanzu ta ce Charon ba a dauke shi duniyar karami ba amma a maimakon haka tauraron dan adam na Pluto, kodayake ra'ayin cewa Charon na iya cancanta a matsayin duniyar karami ana iya la'akari da shi a baya. Duk da haka, ba a bayyana cewa Charon yana cikin daidaitattun ruwa ba. Har ila yau, wurin da baricentre ya dogara ba kawai da dangi na jikin ba, har ma da nisan da ke tsakanin su; baricentre na Sun-Jupiter orbit, alal misali, yana waje da Sun, amma ba a dauke su abu na binary ba. Don haka, dole ne a kafa ma'anar abin da ke cikin duniyar binary (dwarf) kafin a bayyana Pluto da Charon a matsayin taurari masu ƙanƙanta.

## Dubi kuma

## Bayani

## Manazarta

## Haɗin waje

* Gabatarwa ta gani ga Duniyoyin Dwarf a cikin Tsarin Hasken rana (Anshool Deshmukh, Visual Capitalist, Oktoba 8, 2021, zane-zane na Mark Belan) 
* NPR: Dwarf Planets Na iya A ƙarshe Samun Daraja (David Kestenbaum, Morning Edition) 
* Labaran BBC: Tambaya da Sabbin taurari, Agusta 16, 2006
* Ottawa Citizen: Shari'ar da aka yi wa Pluto (P. Surdas Mohit) Agusta 24, 2006
* James L. Hilton: Yaushe Asteroids suka zama Ƙananan Duniyoyi?
* NASA: IYA 2009 Dwarf Planets