Demokloid

Damokloid veya Demokloid (İngilizce: Damocloid), bir tür küçük gezegen grubuna verilen genel isimdir. 5335 Damokles ve 1996 PW gibi küçük gezegenler, yüksek dışmerkezliğe sahip uzun dönemli yörüngeleri olan fakat koması veya kuyruğu olmayan kuyruklu yıldızlar bu sınıfa dahil edilmektedir. David Jewitt bir Damokloid'i Jüpiter'e göre Tisserand parametresi 2 ya da daha az olan bir cisim olarak tanımlarken, Akimasa Nakamura bu grubu aşağıdaki yörünge elemanları uyarınca tanımlamaktadır:

 q < 5.2 AU, a > 8.0 AU ve e > 0,75,
 veya alternatif olarak, i > 90 °

Ancak bu tanım, Jüpiter'e odaklanmamakta ve ,  ve  gibi cisimleri kapsamamaktadır.

Jüpiter'e göre Tisserand parametresinin 2 veya daha az hesaplanması neticesinde Nisan 2023 itibarıyla 258 adet damokloid adayı bulunmaktadır. Bu nesnelerden yörünge gözlem yayı 30 günden daha büyük olanlarının sayısı ise 240'tır. Bu cisimler astronomik fotografide kırmızımsı görünmekle birlikte, diğer Kuiper kuşağı cisimleri ya da centaurlar kadar kırmızı renk vermezler. Diğer damokloidler arasında; , , ,  ve 20461 Dioretsa bulunmaktadır.

Halley kuyrulu yıldızı ve  adlı damokloid gibi ters yön yörüngeli cisimler Dünya'ya oranla  hızda hareket edebilirler.

Damokloid adı, 5335 Damokles adlı küçük gezegenin de adlandırıldığı gibi Yunan mitolojik kahramanı Damokles'ten gelmektedir.

 Köken 
Damokloidlerin Halley tipi kuyruklu yıldızların uçucu materyallerini gaz çıkışı ve sönme nedeniyle kaybeden çekirdekler olabileceği düşünülmektedir. Muhtemelen Oort bulutu kökenlidirler. Bu iddiayı güçlendiren bir diğer kanıt ise damokloid tanımına girebileceği düşünülen bazı cisimlerin kuyruklu yıldız benzeri kuyruklarının bulunmasıdır. Bu kapsamdaki bazı kuyruklu yıldızlar C/2001 OG108 (LONEOS), , ,  ve diğerleridir. Diğer küçük gezegenlerden farklı olarak damokloidlerin ters yön yörüngeye sahip olduğunu gösterir kanıtlar da bu iddiayı güçlendirmektedir. Yörünge eğikliği 90 ila 180 derece arasındaki nesneler ters yön yörüngeyle hareket etmektedirler.

 Liste 
Nisan 2023 itibarıyla JPL SBDB'den alınan listede Akimasa Nakamura'nın damokloid olarak sınıflandırılma kriterlerini karşılayan cisimler aşağıda listelenmektedir. Tisserand'ın Jüpiter'e göre parametresi (TJüpiter) de ayrıca verilmiştir. Akimasa Nakamura'nın kriterleri ve Tisserand parametresi büyük ölçüde birbirini tutmaktadır.

Damokloidlerin çoğu MPC'nin diğer olağandışı küçük gezegenler listesinde de yer almaktadır. Yörünge verileri JPL tarafından numaralandırılmış ve numaralandırılmamış element dosyalarından elde edilmiştir. 
İsimea(AU)q(AU)i(°)Q(AU)DSYılTjüpSınıfKaynak5335 Damocles 1991 DA0,865911,871,59261,6822,1540,91,16CEN15504 1999 RG330,77359,3652,12134,9816,6128,71,95CEN20461 Dioretsa 1999 LD310,901623,822,344160,4345,29116 -1,53CEN65407 2002 RP1200,953953,912,484119,51105,34396 -0,855NÖC154783 2004 PA440,75814,253,4493,2725,0553,82,52CEN606187 2017 QO330,858434,884,94148,8464,81206 -2,12NÖC614592 2009 YS60,91920,221,637147,7738,890,9 -1,06CEN1996 PW0,9909275,72,51830,02548,845801,72NÖC1997 MD100,943326,531,50459,1951,551370,964CEN1998 QJ10,814511,242,08523,620,437,72,03CEN1998 WU240,907915,131,39442,5728,8658,81,4CEN2000 AB2290,95651,992,28568,43101,693750,781NÖC2000 DG80,791610,782,246129,3719,3135,4 -0,633CEN2000 HE460,901123,622,335158,5344,91115 -1,5CEN2000 KP650,962689,123,3345,49174,928411,63NÖC2002 AR910,965275,232,61717,57147,846531,96NÖC2002 RN1090,9957627,42,67158,471252,09157001,07NÖC2003 UY2830,895433,263,47918,8863,051922,29NÖC2003 WN1880,845614,382,2226,9126,5354,51,94CEN2004 CM1110,8533,174,9744,6961,371912,81NÖC2004 NN80,9769100,92,33165,57199,51010 -1,77NÖC2005 HL30,830311,291,91735,5520,6737,91,8CEN2005 OE0,951263,333,08867,51123,585040,905NÖC2005 SB2230,905629,442,77891,6756,11600,118CEN2005 UH5250,907617,781,64314,2233,9174,91,8CEN2005 VX30,9951835,84,116112,591667,5224200 -0,959NÖC2006 BZ80,80189,6081,905165,317,3129,8 -1,03CEN2006 EX520,938742,042,579150,3381,51273 -1,58NÖC2006 LM10,88532,193,702172,1460,67183 -2,13NÖC2006 RG10,920825,762,04133,3649,48131 -0,99CEN2006 RJ20,75889,6792,335164,6717,0230,1 -1,18CEN2006 SO1340,832119,573,2854,235,8686,62,41CEN2007 DA610,9936414,52,64176,57826,3984400,48NÖC2007 TG2500,925921,291,57810,594198,21,75CEN2007 VJ2000,941224,351,4317,1647,271201,66CEN2008 BN180,91430,342,60928,7858,071671,89NÖC2008 SE820,835319,43,19517,4535,6185,52,29CEN2008 WA950,878914,011,69760,3626,3252,41,15CEN2009 AU160,917323,511,94570,1445,071140,797CEN2009 DD470,948142,482,204107,2682,75277 -0,416NÖC2009 FW230,856411,51,65286,421,36390,549CEN2009 KK310,922820,041,54722,8238,5489,71,65CEN2009 QY60,832912,492,087137,9222,8944,1 -0,856CEN2009 SE80,901613,261,30418,0125,2148,31,71CEN2009 WX1990,955131,31,4068,7361,21751,6NÖC2010 BA1010,83289,1271,52626,5516,7327,61,88CEN2010 CG550,909131,582,872146,160,29177 -1,54NÖC2010 CH2470,77810,42,3099,6518,4933,52,25CEN2010 DD570,9883227,52,6538,32452,2834302,02NÖC2010 EB460,955233,251,491156,365,02192 -1,21NÖC2010 EJ1040,921,532,15241,3640,999,91,57CEN2010 ER1440,827410,891,888,8319,91362,08CEN2010 EX1750,946349,392,65229,2196,143471,84NÖC2010 GW640,940661,893,679105,27120,1487 -0,533NÖC2010 HR680,875712,421,54521,923,343,81,8CEN2010 HK1260,831616,562,788121,9230,3267,4 -0,733CEN2010 JH1240,962269,892,64553,37137,145841,27NÖC2010 JC1470,761614,573,47341,6825,6655,61,98CEN2010 JA1910,792510,022,07915,1517,9631,72,15CEN2010 LN1350,999761791,7364,7312357,254860000,697NÖC2010 MK190,804614,862,90425,6326,8157,32,16CEN2010 OR10,923427,092,075143,9152,11141 -1,22CEN2010 OU1000,890617,291,89215,2232,771,91,9CEN2010 OM1010,917926,22,151118,7750,24134 -0,658CEN2010 PK160,904818,821,79227,735,8581,61,71CEN2011 BL400,83159,991,6843,3618,331,62,06CEN2011 OR170,9894293,53,115110,25583,95030 -0,738NÖC2011 SP250,883719,642,285109,323787,1 -0,337CEN2011 UR4020,777918,494,10624,5932,8779,52,44CEN2011 WS410,944937,412,062141,7272,76229 -1,24NÖC2012 HD20,959161,942,533146,67121,35488 -1,55NÖC2012 KA510,9903502,14,87170,89999,27113000,904NÖC2012 TF720,864111,141,5145,320,7637,21,93CEN2012 TT720,86059,5811,3375,0617,8329,71,92CEN2012 TL1390,881529,973,553160,0456,4164 -1,96CEN2012 VG940,829810,571,7988,4619,3434,42,07CEN2013 BN270,973958,831,537101,8116,12451 -0,224NÖC2013 HS1500,951357,562,80297,04112,32437 -0,161NÖC2013 JD40,863911,981,6372,9122,3241,50,884CEN2013 LD160,968680,332,524154,61158,14720 -1,7NÖC2013 LG290,789717,063,58715,3530,5370,52,45CEN2013 NS110,785312,582,7130,4522,4544,6 -0,835CEN2013 PS210,835711,011,80911,2520,2236,52,04CEN2013 RA960,920419,841,585,1838,188,41,78CEN2013 YG480,7528,1612,02461,3914,323,31,43CEN2014 CW140,867932,654,314170,7560,99187 -2,3NÖC2014 HR710,951141,562,03461,8381,082680,95NÖC2014 MH550,899444,734,592,2884,962990,014NÖC2014 QZ1110,865212,181,64115,8522,7242,51,9CEN2014 QW2430,75968,2561,98518,1414,5323,72,19CEN2014 QU2500,86712,331,649,0923,0243,31,94CEN2014 SQ3390,90328,912,803128,5755,02155 -1,08CEN2014 UG60,889212,41,3747,0723,4343,71,82CEN2014 UC2410,75649,5852,3357,3616,8329,72,3CEN2014 XS30,954972,273,259101,64141,28614 -0,374NÖC2015 AO440,833921,833,624139,9340,03102 -1,49CEN2015 AM1070,874512,791,6057,0823,9745,71,92CEN2015 BE3840,8089,3521,7960,3416,9128,62,14CEN2015 BH5260,877416,732,0518,3531,468,42,01CEN2015 FK370,9888441,34,935156,12877,739270 -2,5NÖC2015 KJ870,885911,981,3678,222,5841,41,83CEN2015 RK2450,966482,132,76191,8161,49744 -0,001NÖC2015 RE2770,765420,264,7531,6235,7791,22,8CEN2015 TP100,901914,211,39437,9527,0353,61,49CEN2015 TN1780,956154,212,38291,26106,043990,054NÖC2015 TS3500,965144,95,0757,91284,6717401,51NÖC2015 XX3510,852114,452,136159,1826,7654,9 -1,27CEN2015 XR3840,901136,183,577157,4868,78218 -1,97NÖC2015 YY180,829919,313,283118,2735,3384,8 -0,748CEN2016 AT2810,956662,032,69422,18121,374891,95NÖC2016 CJ1550,764613,293,1297,8123,4548,52,43CEN2016 CO2640,935846,963,015129,7490,91322 -1,24NÖC2016 EJ2030,958265,172,721170,96127,62526 -1,92NÖC2016 GE530,874910,771,3470,5820,1935,31,88CEN2016 GZ1200,831410,721,80810,4819,6335,12,05CEN2016 NL1000,759913,933,34521,9224,52522,35CEN2016 PN660,906631,162,911105,2759,41174 -0,377NÖC2016 US1090,94835,661,85487,3669,472130,223NÖC2016 UK2120,950229,621,4762,2857,771611,66CEN2016 UN2320,861930,394,19911,1756,591682,58NÖC2016 UN2330,936624,861,5771,448,141241,74CEN2016 UG2450,83018,4721,4392,3415,524,72,04CEN2016 VY170,850111,171,674148,5320,6637,3 -0,85CEN2016 WS10,882314,331,68753,1426,9854,31,3CEN2017 AX130,883628,623,332137,2353,9153 -1,43CEN2017 CW320,9832174,82,943152,43346,72310 -1,85NÖC2017 EM40,920132,922,62983,4263,211890,384NÖC2017 GD80,946842,852,28174,8383,432810,605NÖC2017 JB60,884232,953,814160,8562,08189 -2,06NÖC2017 MZ40,952767,793,20465,81132,385580,975NÖC2017 MB70,996311874,44655,842370,31409001,47NÖC2017 OX680,970758,71,72394,72115,68450 -0,044NÖC2017 PY240,925117,411,30471,7533,5272,60,734CEN2017 RR20,782911,652,52987,0520,7639,70,543CEN2017 SV130,79149,6722,017113,3117,3330,1 -0,122CEN2017 SN330,9926251,31,856152,08500,73980 -1,47NÖC2017 SZ1180,954134,081,5642,4666,61991,68NÖC2017 UW510,9751126,63,148144,23250,021420 -1,73NÖC2017 YL20,76588,9052,08527,8615,7226,62,07CEN2017 YL40,97081464,26589,02287,8317700,079NÖC2018 AS180,871112,871,6662,9824,0846,21,11CEN2018 DE40,924231,572,39281,3860,751770,447NÖC2018 DF40,982993,791,60668,24185,979080,636NÖC2018 KH30,959892,513,71746,87181,318901,67NÖC2018 MP80,98973733,84268,28742,1172000,911NÖC2018 PQ180,80798,9531,721,2216,1926,82,13CEN2018 PL280,861319,472,774,1236,2485,90,805CEN2018 SQ130,9809155,72,97690,98308,411940 -0,003NÖC2018 TL60,78848,1471,724170,9214,5723,3 -0,881CENA/2018 V30,989121,41,34164,98241,551340 -1,34NÖCA/2018 W30,99427354,292104,81465,7919900 -0,648NÖCA/2019 G20,9967699,82,291159,211397,4118500 -1,75NÖCA/2019 G30,833617,162,854156,8131,4671,1 -1,54CEN2019 KN190,763812,352,91514,7521,7743,42,34CENA/2019 N20,998210591,94589,432115,35344000,022NÖCA/2019 O40,889232,883,644115,0962,12189 -0,817NÖC2019 PN20,920325,242,012113,0448,47127 -0,468CENA/2019 T10,888138,254,282120,8772,22237 -1,14NÖC2019 YJ60,930836,992,5592271,432251,95NÖCA/2020 A10,935625,941,671149,0550,21132 -1,15CENA/2020 B10,966652,321,74818,51102,883781,64NÖC2020 EP0,763710,472,47576,418,4733,90,927CEN2020 FH240,802616,923,3427,5330,4969,62,21CENA/2020 H90,9925341,52,578137,85680,426310 -1,46NÖC2020 KD60,870813,011,6838,6724,3446,91,61CEN2020 KU70,87934,694,195103,8365,18204 -0,439NÖC2020 KX110,946861,013,24472,58118,774770,745NÖC2020 ML10,954155,282,53882,49108,024110,349NÖC2020 OP70,894428,4379,4753,811510,565CEN2020 QN60,9913552,34,82876,831099,85130000,629NÖC2020 QO60,875619,222,39180,4936,0684,30,578CEN2020 SJ50,856418,282,62577,433,9378,10,707CEN2020 SV790,884117,522,035,7433,0273,42CEN2020 TK90,878320,492,494105,5738,4992,8 -0,256CEN2020 XQ70,917523,471,93532,47451141,65CEN2021 DL10,888135,143,933148,5466,35208 -1,89NÖC2021 DN20,81922,013,98410,8340,041032,56CENA/2021 E20,9894216,42,288167,49430,463180 -1,8NÖCA/2021 E40,9936725,84,676116,361447,0119600 -1,18NÖC2021 FQ20,791910,772,24154,9319,335,31,49CEN2021 GQ570,960286,893,455125,1170,33810 -1,25NÖC2021 LB180,869525,753,361128,9648,14131 -1,18CEN2021 LU440,844929,574,58643,7854,551612,02CEN2021 NS710,905437,363,53520,3871,182282,27NÖC2021 PN720,9857316,24,52584,79627,8756200,255NÖC2021 RM1140,9618105,44,024103,18206,691080 -0,512NÖC2021 TR810,83258,7681,46836,8316,07261,75CEN2021 UL190,949837,031,858154,9272,19225 -1,37NÖC2021 VQ80,78919,3281,96723,2516,6928,52,07CEN2021 VU110,76814,173,28911,8725,0653,42,44CEN2021 XZ30,781514,223,107172,0925,3353,6 -1,68CEN2021 XS60,89938,923,93396,9173,91243 -0,155NÖC2022 AA70,806211,712,269122,4121,1440,1 -0,507CEN2022 AB80,978778,851,67775,13156,037000,476NÖC2022 AC80,807213,592,619153,1524,5650,1 -1,32CEN2022 AZ90,906952,214,86373,4299,563770,861NÖCA/2022 B30,9962980,53,698132,061957,2530700 -1,59NÖC2022 CT70,783210,532,28379,2618,7834,20,824CEN2022 GU0,952937,091,746116,9172,43226 -0,592NÖC2022 GK110,809222,824,355102,4141,29109 -0,301CEN2022 HB50,904536,73,506147,1869,9222 -1,76NÖC2022 JK50,93843,342,68716,8383,992852,04NÖC2022 OC210,951568,933,34493,38134,51572 -0,056NÖC2022 UH420,75599,8082,39424,6117,2230,72,17CEN2022 YU90,78869,0151,906172,7516,1227,1 -1,03CEN

 Ayrıca bakınız 

 Küçük gezegen grupları listesi

 Kaynakça 

 Dış bağlantılar 

 Damocloidlere ilk bakış , David Jewitt, Ocak 2005
 Damocloid ailesi , David J. Darling

Kategori:Demokloid
Kategori:Asteroit grupları ve aileleri
Kategori:Neptün ötesi bölge
Kategori:Küçük gezegenler
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