Periodic comets (also known as short-period comets) are comets with orbital periods of less than 200 years or that have been observed during more than a single perihelion passage^[1] (e.g. 153P/Ikeya–Zhang). "Periodic comet" is also sometimes used to mean any comet with a periodic orbit, even if greater than 200 years.

Periodic comets receive a permanent number prefix usually after the second perihelion passage, which is why there are a number of unnumbered periodic comets, such as P/2005 T5 (Broughton). Comets that are not observed after a number of perihelion passages, or presumed to be destroyed, are given the D designation, and likewise comets given a periodic number and subsequently lost are given D instead of P, such as 3D/Biela or 5D/Brorsen.

In nearly all cases, comets are named after their discoverers, but in a few cases such as 2P/Encke and 27P/Crommelin they were named for a person who calculated their orbits (the orbit computers). The long-term orbits of comets can be difficult to calculate due to errors in the known trajectory that can accumulate from perturbations from the planets. Even so, quite a few comets were lost because their orbits are also affected by non-gravitational effects such as the release of gas and other material that forms the comet's coma and tail. Unlike a long-period comet, the next perihelion passage of a numbered periodic comet can be predicted with a high degree of accuracy.

Periodic comets sometimes bear the same name repeatedly (e.g. the nine Shoemaker–Levy comets or the twenty-four NEAT comets); the IAU system distinguishes between them either through the number prefix or by the full designation (e. g. 181P and 192P/Shoemaker–Levy are both "Comet Shoemaker–Levy"). In the literature, an informal numbering system is applied to periodic comets (skipping the non-periodic ones), thus 181P and 192P are known as Comet Shoemaker–Levy 6 and Comet Shoemaker–Levy 1, respectively. Non-periodic Shoemaker–Levy comets are interleaved in this sequence: C/1991 B1 between 2 and 3, C/1991 T2 between 5 and 6, C/1993 K1 and C/1994 E2 after Shoemaker–Levy 9.

In comet nomenclature, the letter before the "/" is either "C" (a non-periodic comet), "P" (a periodic comet), "D" (a comet that has been lost or has disintegrated), "X" (a comet for which no reliable orbit could be calculated —usually historical comets), "I" for an interstellar object, or "A" for an object that was either mistakenly identified as a comet, but is actually a minor planet,^[1] or for an object on a hyperbolic orbit that does not show cometary activity.^[2] Some lists retain the "C" prefix for comets of periods larger than about 30 years until their return is confirmed.^[3]

List of Halley-type comets

List of unnumbered Jupiter-Family comets

While Jupiter-family comets are officially defined by 2 < T_Jupiter < 3, they can also be loosely defined as any comet with a period of less than 20 years, a relatively low inclination, and an orbit coinciding loosely with that of Jupiter. These comets are often patchily observed, as orbital interactions with the planet often cause comets' orbits to become perturbed, causing them to not be found at the expected position in the sky and subsequently lost. Additionally, their low cometary albedos and frequent proximity to the Sun compared to Oort Cloud comets cause them to much more quickly become depleted of volatiles, making them comparatively dimmer than comets with longer orbital periods.

Zdroj:https://en.wikipedia.org?pojem=Periodic_comet
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Comet designation	Name/ discoverer(s)	Period (years)	e	a (AU)	q (AU)	i (°)	Abs. mag (M1)	Last observed perihelion	Next perihelion	Ref
X/1979 O3	Kowal	5.44	0.33	3.09	2.07	1.75	15.8	1979/07/26	1985
X/1981 R1	Stattmayer	3.84	0.26	2.45	1.28	11.00	13.4	1981/08/18	1986
X/1991 G1	Meyer	3.73	0.44	2.41	1.36	5.96	18.7	1991/04/11	1995[4]
P/1996 R2	Lagerkvist	7.36	0.30998	3.782	2.60964	2.6054	6.3	1997/01/19	2004/05/30	MPC · JPL
P/1998 VS24	LINEAR	9.56	0.24393	4.5041	3.4054	5.031	11.3	1998/11/03	2008/05/26	MPC · JPL
C/1999 J6	SOHO	5.46	0.98418	3.1005	0.04906	26.61		2004/11/08	2021/03/27	MPC · JPL
P/1999 RO28	LONEOS	6.62	0.65079	3.5272	1.23176	8.191	19.4	1999/10/02	2006/05/17	MPC · JPL
P/1999 XN120	Catalina	8.55	0.21391	4.1806	3.2863	5.0283	9.9	2000/05/01	2008/11/17	MPC · JPL
P/2000 R2	LINEAR	6.1	0.5837	3.338	1.38997	3.2163	17.6	2000/09/12	2006/10/18	MPC · JPL
P/2001 H5	NEAT	14.68	0.6002	5.995	2.3966	8.3993	6.8	2001/01/28	2015/10/03	MPC · JPL
P/2002 EJ57	LINEAR	16.53	0.59391	6.49	2.6355	4.9697	15.8	2001/12/19	2018/06/30	MPC · JPL
C/2002 R5	SOHO	5.77	0.98526	3.21612	0.0474	14.12		2002/09/05	2008/02/02	MPC · JPL
P/2002 S7	SOHO	5.79	0.98496	3.22344	0.04849	13.6		2002/09/21	2008/07/06	MPC · JPL
P/2003 F2	NEAT	16.58	0.54219	6.503	2.9772	11.605	13.7	2003/04/14	2019/11/12	MPC · JPL
P/2003 T12	SOHO	4.12	0.775433	2.570078	0.57716	11.4579	19.7	2016/03/09	2020/05/06	MPC · JPL
X/2004 D5	Murakami				1.1			2004/02/15	?
P/2004 FY140	LINEAR	11.02	0.1709	4.9523	4.1061	2.1279	12.5	2004/08/06	2015/08/13	MPC · JPL
P/2004 R3	LINEAR-NEAT	7.52	0.44184	3.8367	2.14148	7.9723	13.5	2004/05/24	2011/11/30	MPC · JPL
P/2005 E1	Tubbiolo	19.42	0.3847	7.225	4.4456	5.154	10.7	2005/03/18	2024/08/15	MPC · JPL
P/2005 J1	McNaught	6.74	0.57096	3.5664	1.53015	31.7659	13.4	2005/04/17	2012/01/12	MPC · JPL
P/2005 L1	McNaught	7.92	0.20924	3.9745	3.1428	7.7369	10.2	2005/12/13	2013/11/14	MPC · JPL
P/2005 SB216	LONEOS	18.97	0.463208	7.11312	3.818266	24.09843	9.9	2007/02/11	2018/01/31	MPC · JPL
P/2005 T5	Broughton	19.54	0.55245	3.2468	3.2468	21.3724	11.2	2005/11/03	2025/05/19	MPC · JPL
P/2005 XR132	Spacewatch	7.29	0.432	3.759	2.135	14.475	16.44	2020/11/26	2028	MPC · JPL
P/2007 C2	Catalina	18.63	0.462251	7.0283	3.779481	8.6747	10	2007/09/04	2026/04/22	MPC · JPL
P/2007 K2	Gibbs	19.23	0.684	7.18	2.2686	7.6197	14	2007/06/08	2026/09/01	MPC · JPL
P/2007 Q2	Gilmore	13.23	0.67123	5.594	1.83902	10.2384	16.7	2007/08/23	2020/11/15	MPC · JPL
P/2007 S1	Zhao	7.4	0.34339	3.7989	2.4944	5.973	13.5	2007/12/06	2015/05/01	MPC · JPL
P/2007 T2	Kowalski	5.43	0.77483	3.0904	0.695863	9.89528	18.6	2007/09/19	2013/02/23	MPC · JPL
P/2008 Y12	SOHO	5.4	0.9787	3.07822	0.0654	23.35		2008/12/22	2014/05/17	MPC · JPL
P/2009 B1	Boattini	17.3	0.63719	6.688	2.42659	22.2285	13.2	2009/02/06	2026/05/27	MPC · JPL
P/2009 WX51	Catalina	5.41	0.740297	3.0803	0.799956	9.5926	20.6	2010/01/31	2015/06/30	MPC · JPL
P/2009 Y2	Kowalski	16.6	0.64052	6.507	2.33919	29.9296	6.1	2010/03/30	2026/11/04	MPC · JPL
P/2010 A3	Hill	14.91	0.73223	6.0568	1.621828	15.02825	6.5	2010/04/03	2025/03/01	MPC · JPL
P/2010 C1	Scotti	18.78	0.25911	7.0657	5.2349	9.14247	5.7	2009/12/01	2028/09/12	MPC · JPL
P/2010 D2	WISE	17.3	0.45301	6.6894	3.65902	57.17704	11.1	2010/03/05	2027/06/23	MPC · JPL
P/2010 H2	Vales	7.56	0.192894	3.85038	3.10767	14.2529	6.9	2010/03/09	2017/09/29	MPC · JPL
P/2010 H4	Scotti	17.05	0.272	6.624	4.821	2.314	10.8	2010/07/03	2027/07/21	MPC · JPL
P/2010 H5	Scotti	19.09	0.15646	7.1436	6.0259	14.0871	9.6	2010/04/17	2029/05/20	MPC · JPL
P/2010 T2	PANSTARRS	13.06	0.3231	5.546	3.754	8.0109	6.4	2011/07/09	2024/07/31	MPC · JPL
P/2010 U1	Boattini	17.09	0.26112	6.636	4.90317	8.24623	6	2010/03/28	2027/04/30	MPC · JPL
P/2010 UH55	Spacewatch	16.63	0.57514	6.515	2.767969	8.66257	6.6	2011/05/10	2027/12/26	MPC · JPL
P/2010 WK	LINEAR	13.72	0.691987	5.7309	1.765178	11.47913	12.4	2010/10/19	2024/07/09	MPC · JPL
P/2011 C2	Gibbs	19.99	0.26846	7.366	5.38854	10.91098	6.2	2012/01/07	2032/01/03	MPC · JPL
P/2011 FR143	Lemmon	17.85	0.45305	6.8296	3.73541	16.01358	11.1	2011/03/10	2029/01/14	MPC · JPL
P/2011 N1	ASH	15.79	0.545926	6.2935	2.857712	35.66877	10.3	2012/05/31	2028/03/15	MPC · JPL
P/2011 UA134	Spacewatch-PANSTARRS	13.2	0.6327	5.5854	2.05151	10.5395	15.7	2011/12/07	2025/02/18	MPC · JPL
P/2011 V1	Boattini	7.53	0.555	3.843	1.7094	7.397	13.7	2011/05/11	2018/11/15	MPC · JPL
P/2011 W1	PANSTARRS	10.05	0.28866	4.65606	3.31206	3.71861	6.2	2012/01/22	2022/02/09	MPC · JPL
P/2011 Y2	Boattini	15.53	0.71291	6.2251	1.787145	6.35139	13.6	2012/03/21	2027/09/03	MPC · JPL
P/2012 B1	PANSTARRS	16.53	0.4104966	6.4887702	3.8251522	7.62779	5.6	2013/07/23	2030/02/01	MPC · JPL
P/2012 F2	PANSTARRS	15.92	0.54224	6.3287	2.89707	14.72465	12	2013/04/10	2029/03/12	MPC · JPL
P/2012 G1	PANSTARRS	8.60	0.3852	4.1967	2.580	11.6965	15.2	2012/06/06	2021/01/08	MPC · JPL
P/2012 K3	Gibbs	6.88	0.42596	3.618	2.07686	13.2012	6.9	2012/09/30	2019/08/17	MPC · JPL
P/2012 O1	McNaught	6.73	0.57925	3.563	1.499145	11.4286	16.6	2012/07/23	2019/04/15	MPC · JPL
P/2012 O2	McNaught	6.82	0.53827	3.597	1.660834	24.5274	17.3	2012/06/25	2019/04/20	MPC · JPL
P/2012 S2	La Sagra	9.33	0.69059	4.4316	1.371192	8.58181	15.3	2021/12/16	2031/02/11	MPC · JPL
P/2012 SB6	Lemmon	7.73	0.38462	3.91053	2.4065	10.9897	14.1	2020/07/24	2027/12/21	MPC · JPL
P/2012 T2	PANSTARRS	13.73	0.159	5.735	4.823	12.562	10.2	2013/04/10	2026/12/31	MPC · JPL
P/2012 T3	PANSTARRS	14.66	0.602	5.990	2.39	9.51	14.8	2012/04/15	2026/12/24	MPC · JPL
P/2012 U2	PANSTARRS	19.94	0.50657	7.3522	3.6278	10.5345	12.1	2012/12/04	2032/11/12	MPC · JPL
P/2012 US27	Siding Spring	11.79	0.64858	5.1814	1.820844	39.29295	6.8	2013/02/08	2024/11/23