Damocloid

Damocloids are a class of minor planets such as 5335 Damocles and 1996 PW that have Halley-family or long-period highly eccentric orbits typical of periodic comets such as Halley's Comet, but without showing a cometary coma or tail. David Jewitt defines a damocloid as an object with a Tisserand's parameter relative to Jupiter of 2 or less ( $T J \leq 2$ ),^[1] while Akimasa Nakamura defines this group with the following orbital criterion:^[2]

q < 5.2 AU, a > 8.0 AU, and e > 0.75,
or alternatively, i > 90°

However, this definition that does not focus on Jupiter excludes objects such as (127546) 2002 XU₉₃, 2003 WG₁₆₆, and 2004 DA₆₂.^[3]

Using the Tisserand's parameter with respect to Jupiter of 2 or less, there are currently 155 damocloid candidates.^[4] Of these objects, 122 have orbital observation arcs greater than 30 days providing reasonably decent orbits.^[5]^[1] Their average radius is eight kilometers assuming an albedo of 0.04. The albedos of four damocloids have been measured, and they are among the darkest objects known in the Solar System. Damocloids are reddish in color, but not as red as many Kuiper-belt objects or centaurs. Other damocloids include: 2013 BL76, 2012 DR30, 2008 KV42, (65407) 2002 RP120, and 20461 Dioretsa.

Retrograde objects such as Halley's Comet and damocloid (343158) 2009 HC82 can have relative velocities to Earth of 81 km/s (290,000 km/h).^[6]

Origin

Damocloids are thought to be nuclei of Halley-type comets that have lost all their volatile materials due to outgassing and become dormant. Such comets probably originate from the Oort cloud. This hypothesis is strengthened by the fact that a number of objects thought to be damocloids (and assigned minor-planet provisional designations) subsequently showed a coma and were confirmed to be comets: C/2001 OG₁₀₈ (LONEOS), C/2002 CE₁₀ (LINEAR), C/2002 VQ₉₄ (LINEAR), C/2004 HV₆₀ (Spacewatch) and possibly others. Another strong indication of cometary origin is the fact that some damocloids have retrograde orbits, unlike any other minor planets. (Objects with an inclination beyond 90 degrees up to 180 degrees are in a retrograde orbit and orbit in the opposite direction of other objects.)

List

This is a list of 14 numbered and 128 unnumbered bodies from the JPL SBDB as of April 2018, that meet Akimasa Nakamura's criteria for being classified as a damocloid, that is, either a retrograde orbit, or the following orbital elements: q < 5.2 AU, a > 8.0 AU, and e > 0.75 (also see § top). Tisserand's parameter with respect to Jupiter (T_Jupiter) is also given. Akimasa Nakamura's criteria and a T_Jupiter of less than 2 are largely equivalent as only 9 of the listed bodies (6%) do not meet the defined T_Jupiter threshold.

Designation	a (AU)	e	i (°)	Orbital criteria and classes				q (AU)	Q (AU)	Catalog	Refs
Designation	a (AU)	e	i (°)	Cls	Retro	T_Jupiter	T_J ≤ 2	q (AU)	Q (AU)	Catalog	Refs
5335 Damocles	11.83	0.867	61.8	CEN	—	1.15	Y	1.58	22.08	LoMP	JPL · MPC
(15504) 1999 RG₃₃	9.39	0.773	34.9	CEN	—	1.952	Y	2.13	16.65	LoMP	JPL · MPC
20461 Dioretsa	23.88	0.899	160.4	CEN	Y	-1.55	Y	2.41	45.35	LoMP	JPL · MPC
(65407) 2002 RP120	54.22	0.955	118.9	TNO	Y	-0.833	Y	2.46	105.99	LoMP	JPL · MPC
(154783) 2004 PA₄₄	14.2	0.76	3.3	CEN	—	2.512	—	3.41	24.99	LoMP	JPL · MPC
(330759) 2008 SO₂₁₈	8.11	0.565	170.3	CEN	Y	-1.389	Y	3.53	12.7	LoMP	JPL · MPC
(336756) 2010 NV1	302.69	0.969	140.8	TNO	Y	-2.904	Y	9.4	595.99	LoMP	JPL · MPC
(342842) 2008 YB₃	11.63	0.44	105.1	CEN	Y	-0.25	Y	6.5	16.75	LoMP	JPL · MPC
(343158) 2009 HC82	2.53	0.807	154.4	NEO	Y	1.317	Y	0.49	4.57	LoMP	JPL · MPC
(434620) 2005 VD	6.67	0.252	172.9	CEN	Y	-1.394	Y	4.99	8.35	LoMP	JPL · MPC
(459870) 2014 AT₂₈	10.93	0.404	165.6	CEN	Y	-2.092	Y	6.51	15.36	LoMP	JPL · MPC
(468861) 2013 LU₂₈	175.51	0.95	125.4	TNO	Y	-2.064	Y	8.73	342.3	LoMP	JPL · MPC
(471325) 2011 KT19	35.58	0.331	110.1	TNO	Y	-1.55	Y	23.81	47.35	LoMP	JPL · MPC
(514107) 2015 BZ509	5.14	0.381	163	Other	Y	-0.745	Y	3.18	7.09	LoMP	JPL · MPC
1996 PW	251.53	0.99	29.8	TNO	—	1.72	Y	2.51	500.56	—	JPL · MPC
1997 MD₁₀	26.47	0.942	59.4	CEN	—	0.97	Y	1.54	51.39	—	JPL · MPC
1998 QJ₁	11.26	0.813	23.6	CEN	—	2.03	—	2.1	20.41	—	JPL · MPC
1998 WU₂₄	15.16	0.905	42.5	CEN	—	1.413	Y	1.44	28.88	—	JPL · MPC
1999 LE31	8.13	0.466	151.8	CEN	Y	-1.311	Y	4.34	11.93	—	JPL · MPC
1999 XS35	17.8	0.946	19.4	NEO	—	1.421	Y	0.96	34.65	—	JPL · MPC
2000 AB₂₂₉	52.89	0.956	68.6	TNO	—	0.781	Y	2.32	103.47	—	JPL · MPC
2000 DG8	10.76	0.794	129.3	CEN	Y	-0.623	Y	2.21	19.31	—	JPL · MPC
2000 HE₄₆	23.6	0.899	158.5	CEN	Y	-1.517	Y	2.39	44.8	—	JPL · MPC
2000 KP₆₅	90.26	0.964	45.7	TNO	—	1.614	Y	3.29	177.24	—	JPL · MPC
2002 RN109	564.22	0.995	58	TNO	—	1.088	Y	2.7	1125.75	—	JPL · MPC
2003 UY₂₈₃	33.34	0.895	18.9	TNO	—	2.294	—	3.51	63.17	—	JPL · MPC
2003 WN₁₈₈	14.39	0.848	26.9	CEN	—	1.935	Y	2.19	26.58	—	JPL · MPC
2004 CM₁₁₁	33.93	0.852	4.7	TNO	—	2.819	—	5.03	62.84	—	JPL · MPC
2004 NN₈	97.47	0.976	165.5	TNO	Y	-1.774	Y	2.35	192.58	—	JPL · MPC
2005 HL₃	11.28	0.833	35.7	CEN	—	1.784	Y	1.88	20.67	—	JPL · MPC
2005 NP₈₂	5.87	0.478	130.5	CEN	Y	-0.327	Y	3.07	8.68	—	JPL · MPC
2005 OE	62.72	0.952	67.5	TNO	—	0.897	Y	3.03	122.41	—	JPL · MPC
2005 SB₂₂₃	29.47	0.906	91.3	CEN	Y	0.132	Y	2.77	56.17	—	JPL · MPC
2005 TJ₅₀	9.24	0.589	110.2	CEN	Y	-0.181	Y	3.8	14.68	—	JPL · MPC
2005 VX3	1042.77	0.996	112.2	TNO	Y	-0.946	Y	4.12	2081.42	—	JPL · MPC
2006 BZ₈	9.61	0.803	165.3	CEN	Y	-1.026	Y	1.89	17.32	—	JPL · MPC
2006 EX₅₂	42.71	0.94	150.2	TNO	Y	-1.577	Y	2.57	82.84	—	JPL · MPC
2006 LM₁	37.18	0.9	172.1	TNO	Y	-2.166	Y	3.71	70.66	—	JPL · MPC
2006 RG₁	25.39	0.921	133.4	CEN	Y	-0.978	Y	2.01	48.76	—	JPL · MPC
2006 RJ₂	9.68	0.762	164.6	CEN	Y	-1.164	Y	2.3	17.05	—	JPL · MPC
2006 SO₁₃₄	19.53	0.83	4.2	CEN	—	2.42	—	3.31	35.75	—	JPL · MPC
2007 DA₆₁	496.46	0.995	76.7	TNO	—	0.476	Y	2.68	990.24	—	JPL · MPC
2007 VW₂₆₆	5.44	0.39	108.3	Other	Y	0.365	Y	3.32	7.56	—	JPL · MPC
2008 BN₁₈	30.42	0.914	28.8	TNO	—	1.888	Y	2.61	58.24	—	JPL · MPC
2008 KV42	41.5	0.491	103.4	TNO	Y	-1.015	Y	21.11	61.9	—	JPL · MPC
2008 SE₈₂	19.31	0.835	17.4	CEN	—	2.292	—	3.19	35.43	—	JPL · MPC
2008 WA₉₅	14.06	0.877	60.2	CEN	—	1.156	Y	1.73	26.39	—	JPL · MPC
2009 AU₁₆	23.68	0.918	69.8	CEN	—	0.804	Y	1.94	45.43	—	JPL · MPC
2009 DD₄₇	47.98	0.954	107.5	TNO	Y	-0.439	Y	2.22	93.73	—	JPL · MPC
2009 FW₂₃	11.52	0.855	86.6	CEN	—	0.542	Y	1.67	21.37	—	JPL · MPC
2009 QY₆	12.47	0.835	137.6	CEN	Y	-0.842	Y	2.06	22.88	—	JPL · MPC
2009 YS₆	20.18	0.921	147.8	CEN	Y	-1.044	Y	1.6	38.76	—	JPL · MPC
2010 BK118	416.05	0.985	143.9	TNO	Y	-2.451	Y	6.09	826.02	—	JPL · MPC
2010 CG₅₅	32	0.91	146.3	TNO	Y	-1.548	Y	2.88	61.12	—	JPL · MPC
2010 EB₄₆	31.43	0.952	156.6	TNO	Y	-1.213	Y	1.5	61.35	—	JPL · MPC
2010 EJ₁₀₄	21.64	0.901	41.6	CEN	—	1.564	Y	2.14	41.14	—	JPL · MPC
2010 EQ₁₆₉	2.05	0.102	91.6	MBA	Y	2.501	—	1.84	2.26	—	JPL · MPC
2010 GW₆₄	63.35	0.941	105.2	TNO	Y	-0.538	Y	3.73	122.98	—	JPL · MPC
2010 GW₁₄₇	165.99	0.968	99.8	TNO	Y	-0.452	Y	5.38	326.59	—	JPL · MPC
2010 JH₁₂₄	69.18	0.962	53.4	TNO	—	1.256	Y	2.6	135.77	—	JPL · MPC
2010 JC₁₄₇	14.62	0.763	41.8	CEN	—	1.971	Y	3.46	25.78	—	JPL · MPC
2010 LG₆₁	7.07	0.807	123.7	CEN	Y	-0.029	Y	1.37	12.77	—	JPL · MPC
2010 OR₁	26.99	0.925	143.9	CEN	Y	-1.209	Y	2.04	51.95	—	JPL · MPC
2010 OM₁₀₁	26.06	0.919	118.8	CEN	Y	-0.65	Y	2.12	50.01	—	JPL · MPC
2010 PO₅₈	13.25	0.78	121.3	CEN	Y	-0.646	Y	2.91	23.58	—	JPL · MPC
2011 MM₄	21.13	0.473	100.5	CEN	Y	-0.4	Y	11.14	31.12	—	JPL · MPC
2011 OR₁₇	259.22	0.988	110.5	TNO	Y	-0.742	Y	3.11	515.33	—	JPL · MPC
2011 SP₂₅	19.58	0.884	109	CEN	Y	-0.324	Y	2.27	36.89	—	JPL · MPC
2011 UR₄₀₂	18.73	0.78	24.6	CEN	—	2.436	—	4.11	33.35	—	JPL · MPC
2011 WS₄₁	38.31	0.946	141.6	TNO	Y	-1.248	Y	2.08	74.54	—	JPL · MPC
2012 HD₂	62.39	0.959	146.9	TNO	Y	-1.563	Y	2.56	122.21	—	JPL · MPC
2012 KA₅₁	224.45	0.978	70.7	TNO	—	0.928	Y	4.91	444	—	JPL · MPC
2012 TL₁₃₉	30.14	0.883	160	TNO	Y	-1.949	Y	3.52	56.77	—	JPL · MPC
2012 YO₆	6.32	0.478	106.9	CEN	Y	0.261	Y	3.3	9.34	—	JPL · MPC
2012 YE₈	9.38	0.592	136.1	CEN	Y	-1.005	Y	3.83	14.93	—	JPL · MPC
2013 BN₂₇	66.41	0.976	101.8	TNO	Y	-0.238	Y	1.57	131.26	—	JPL · MPC
2013 BL76	1036.23	0.992	98.6	TNO	Y	-0.53	Y	8.36	2064.1	—	JPL · MPC
2013 HS₁₅₀	26.15	0.894	96.5	CEN	Y	-0.027	Y	2.78	49.52	—	JPL · MPC
2013 JD₄	12.1	0.866	73	CEN	—	0.877	Y	1.62	22.58	—	JPL · MPC
2013 LA2	7.51	0.594	175.2	CEN	Y	-1.233	Y	3.05	11.97	—	JPL · MPC
2013 LD₁₆	79.99	0.968	154.8	TNO	Y	-1.712	Y	2.55	157.43	—	JPL · MPC
2013 LG₂₉	16.95	0.791	15.4	CEN	—	2.438	—	3.55	30.35	—	JPL · MPC
2013 NS₁₁	12.65	0.787	130.3	CEN	Y	-0.834	Y	2.7	22.61	—	JPL · MPC
2013 YG₄₈	8.19	0.752	61.3	CEN	—	1.429	Y	2.03	14.36	—	JPL · MPC
2014 CW₁₄	27.76	0.846	170.7	CEN	Y	-2.246	Y	4.28	51.24	—	JPL · MPC
2014 JJ₅₇	6.99	0.293	95.9	CEN	Y	0.516	Y	4.94	9.04	—	JPL · MPC
2014 MH₅₅	27.54	0.838	91.5	CEN	Y	0.124	Y	4.45	50.63	—	JPL · MPC
2014 PP₆₉	21.36	0.942	93.6	NEO	Y	0.157	Y	1.25	41.46	—	JPL · MPC
2014 SQ₃₃₉	28.66	0.903	128.5	CEN	Y	-1.075	Y	2.78	54.54	—	JPL · MPC
2014 UV₁₁₄	6.36	0.385	170.5	CEN	Y	-1.195	Y	3.91	8.81	—	JPL · MPC
2014 XS₃	75.07	0.957	101.4	TNO	Y	-0.367	Y	3.25	146.89	—	JPL · MPC
2015 AO₄₄	22.15	0.836	140	CEN	Y	-1.497	Y	3.63	40.67	—	JPL · MPC
2015 BH₃₁₁	9.17	0.729	94.5	CEN	Y	0.424	Y	2.49	15.85	—	JPL · MPC
2015 FK₃₇	191.08	0.974	156.1	TNO	Y	-2.478	Y	4.95	377.22	—	JPL · MPC
2015 RK₂₄₅	81.99	0.966	91.6	TNO	Y	0.007	Y	2.76	161.22	—	JPL · MPC
2015 TN₁₇₈	57.01	0.958	91.1	TNO	Y	0.055	Y	2.39	111.64	—	JPL · MPC
2015 TS₃₅₀	138.64	0.964	58.1	TNO	—	1.497	Y	5.05	272.23	—	JPL · MPC
2015 XN₆₃	19.91	0.932	19.7	CEN	—	1.601	Y	1.36	38.45	—	JPL · MPC
2015 XX₃₅₁	14.61	0.854	159.1	CEN	Y	-1.27	Y	2.13	27.09	—	JPL · MPC
2015 XR₃₈₄	37.1	0.904	157.5	TNO	Y	-1.974	Y	3.58	70.62	—	JPL · MPC
2015 YY₁₈	19.5	0.831	118.2	CEN	Y	-0.752	Y	3.29	35.7	—	JPL · MPC
2016 CO₂₆₄	48.39	0.938	129.8	TNO	Y	-1.251	Y	3.02	93.77	—	JPL · MPC
2016 DF₂	5.58	0.415	166.8	CEN	Y	-0.904	Y	3.27	7.9	—	JPL · MPC
2016 EJ₂₀₃	67.48	0.959	171	TNO	Y	-1.928	Y	2.74	132.23	—	JPL · MPC
2016 FH₁₃	24.55	0.615	93.5	CEN	Y	0.002	Y	9.46	39.64	—	JPL · MPC
2016 JK₂₄	13.05	0.66	152.3	CEN	Y	-1.708	Y	4.43	21.66	—	JPL · MPC
2016 LS	13.34	0.608	114.3	CEN	Y	-0.659	Y	5.24	21.45	—	JPL · MPC
2016 NM₅₆	73.5	0.857	144	TNO	Y	-3.066	Y	10.52	136.47	—	JPL · MPC
2016 PN₆₆	31.46	0.908	105.1	TNO	Y	-0.372	Y	2.9	60.02	—	JPL · MPC
2016 PO₆₆	49.66	0.996	53.1	NEO	—	0.442	Y	0.21	99.12	—	JPL · MPC
2016 TK₂	9.18	0.552	92.3	CEN	Y	0.477	Y	4.12	14.24	—	JPL · MPC
2016 TP₉₃	7.48	0.56	138.3	CEN	Y	-0.787	Y	3.29	11.67	—	JPL · MPC
2016 US₁₀₉	36.45	0.949	87.2	TNO	—	0.225	Y	1.86	71.03	—	JPL · MPC
2016 VY₁₇	11.2	0.851	148.4	CEN	Y	-0.847	Y	1.67	20.73	—	JPL · MPC
2016 WS₁	14.48	0.883	53	CEN	—	1.303	Y	1.7	27.26	—	JPL · MPC
2016 YB₁₃	5.46	0.408	139.7	Other	Y	-0.473	Y	3.23	7.69	—	JPL · MPC
2017 AX₁₃	28.5	0.882	137.2	CEN	Y	-1.433	Y	3.35	53.66	—	JPL · MPC
2017 BD₈₆	5.5	0.475	159.2	CEN	Y	-0.746	Y	2.89	8.11	—	JPL · MPC
2017 CW₃₂	187.66	0.984	152.4	TNO	Y	-1.855	Y	2.96	372.37	—	JPL · MPC
2017 EE	17.92	0.884	73.9	CEN	—	0.772	Y	2.08	33.76	—	JPL · MPC
2017 EM₄	33.5	0.921	83.4	TNO	—	0.382	Y	2.65	64.35	—	JPL · MPC
2017 GD₈	43.29	0.947	74.9	TNO	—	0.601	Y	2.28	84.3	—	JPL · MPC
2017 JB₆	32.8	0.884	160.9	TNO	Y	-2.06	Y	3.81	61.78	—	JPL · MPC
2017 KZ₃₁	53.1	0.794	161.7	TNO	Y	-3.593	Y	10.96	95.23	—	JPL · MPC
2017 MZ₄	66.2	0.952	65.8	TNO	—	0.973	Y	3.18	129.21	—	JPL · MPC
2017 MB7	4059.09	0.999	55.7	TNO	—	1.474	Y	4.45	8113.72	—	JPL · MPC
2017 NM₂	14.67	0.625	101.3	CEN	Y	-0.159	Y	5.5	23.84	—	JPL · MPC
2017 OX₆₈	59.01	0.971	94.7	TNO	Y	-0.046	Y	1.74	116.29	—	JPL · MPC
2017 PY₂₄	17.38	0.924	71.8	CEN	—	0.736	Y	1.31	33.45	—	JPL · MPC
2017 QO₃₃	34.55	0.857	148.8	TNO	Y	-2.12	Y	4.93	64.17	—	JPL · MPC
2017 RR₂	17.21	0.849	88.6	CEN	—	0.35	Y	2.61	31.82	—	JPL · MPC
2017 SV₁₃	9.68	0.793	113.2	CEN	Y	-0.119	Y	2.01	17.36	—	JPL · MPC
2017 SN₃₃	280.77	0.993	152.1	TNO	Y	-1.465	Y	1.84	559.71	—	JPL · MPC
2017 UW₅₁	137.18	0.977	144.2	TNO	Y	-1.732	Y	3.13	271.23	—	JPL · MPC
2017 UX₅₁	30.26	0.749	90.5	TNO	Y	0.142	Y	7.61	52.91	—	JPL · MPC
2017 UR₅₂	411.87	0.997	108.2	NEO	Y	-0.42	Y	1.24	822.49	—	JPL · MPC
2018 AS₁₈	13.02	0.873	63	CEN	—	1.101	Y	1.66	24.39	—	JPL · MPC
2018 DE₄	32.65	0.927	81.3	TNO	—	0.443	Y	2.39	62.9	—	JPL · MPC
2018 DF₄	100.35	0.984	68.2	TNO	—	0.632	Y	1.6	199.11	—	JPL · MPC
2018 DO₄	27.52	0.912	160.5	CEN	Y	-1.5900	Y	2.42	52.61	—	JPL · MPC
2018 EN₄	18.34	0.921	81.6	CEN	—	0.4980	Y	1.45	35.24	—	JPL · MPC
2018 EF₉	533.09	0.997	84.7	TNO	—	0.1530	Y	1.56	1064.62	—	JPL · MPC

References

1 2 David Jewitt (August 2013). "The DAMOCLOIDS". UCLA, Department of Earth and Space Sciences. Retrieved 2014-02-14. (2013 list / 2011 list / 2010 list)
↑ Akimasa Nakamura and bas (2 May 2009). "List of Damocloids (Oort cloud asteroids)". Lowell Observatory. Retrieved 15 February 2017.
↑ Jewitt, David (2005). "A first look at the Damocloids" (PDF). The Astronomical Journal. 129 (1): 530–538. Bibcode:2005AJ....129..530J. doi:10.1086/426328. Retrieved 2011-02-13.
↑ "JPL Small-Body Database Search Engine: asteroids and T-Jupiter <= 2". JPL Solar System Dynamics. Retrieved 2017-02-20. Search parameters used: Limited by object type/group: Asteroids and T-Jupiter <= 2
↑ "JPL Small-Body Database Search Engine: asteroids and T-Jupiter <= 2 and data-arc span > 30 (d)". JPL Solar System Dynamics. Retrieved 2017-11-07.
↑ "NEO Close-Approaches (Between 1900 and 2200)". NASA/JPL Near-Earth Object Program. Retrieved 2012-06-22. (sorted by descending relative velocity, dist<0.5AU = "215,221 close-Earth approaches")

External links

David Jewitt, A first look at the Damocloids, January 2005

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[Jewitt-1] 1 2 David Jewitt (August 2013). "The DAMOCLOIDS". UCLA, Department of Earth and Space Sciences. Retrieved 2014-02-14. (2013 list / 2011 list / 2010 list)

[Nakamura-Damocloid-list-2] Akimasa Nakamura and bas (2 May 2009). "List of Damocloids (Oort cloud asteroids)". Lowell Observatory. Retrieved 15 February 2017.

[Jewitt2005-3] Jewitt, David (2005). "A first look at the Damocloids" (PDF). The Astronomical Journal. 129 (1): 530–538. Bibcode:2005AJ....129..530J. doi:10.1086/426328. Retrieved 2011-02-13.

[jpl-search-4] "JPL Small-Body Database Search Engine: asteroids and T-Jupiter <= 2". JPL Solar System Dynamics. Retrieved 2017-02-20. Search parameters used: Limited by object type/group: Asteroids and T-Jupiter <= 2

[jpl-30day-5] "JPL Small-Body Database Search Engine: asteroids and T-Jupiter <= 2 and data-arc span > 30 (d)". JPL Solar System Dynamics. Retrieved 2017-11-07.

[velocity-6] "NEO Close-Approaches (Between 1900 and 2200)". NASA/JPL Near-Earth Object Program. Retrieved 2012-06-22. (sorted by descending relative velocity, dist<0.5AU = "215,221 close-Earth approaches")

Damocloid

Origin

List

See also

References

External links