Encke (2P)

NEO ⇩ IMP ⇩ COV ★ EPH ⇩ OBS ⇩ Radar
Orbital Elements
Epoch (TDB)2022-10-03 (JD 2459855.5)
Eccentricity (e)0.8477003353 ± 2.19e-07
Semi-major axis (a)2.2196888070 AU ± 1.36e-07
Inclination (i)11.40704099° ± 2.08e-05
Long. of Asc. Node (Ω)334.18510998° ± 5.54e-05
Arg. of Perihelion (ω)187.14215822° ± 5.56e-05
Mean Anomaly (M)245.50091097° ± 1.14e-05
Mean Motion (n)0.2980340852°/day ± 2.73e-08
Perihelion dist (q)0.33805786 AU ± 4.86e-07
Aphelion dist (Q)4.10131975 AU ± 5.46e-07
Orbital Period3.30709248 yr ± 3.03e-07
Physical Parameters
Diameter4.800 km
Geometric Albedo0.046
Rotation Period11.083 h
Orbit Solution
SourceJPL
Solution Date2026-08-13 12:41:21
RMS Residual0.448″
Uncertainty1
Orbit TypeEncke-type Comet
MOID0.166917 AU
Observations Used645
Oppositions—
Arc Total2018-2026
First Observation Used—
Last Observation Used2026-08-11
Observations (6393)
Date Type RA Dec Mag Band Observatory
2020-09-07 10:15:43 C 16 30 36.16 -31 47 47.7 – q Q68
2020-09-07 10:17:58 C 16 30 36.58 -31 47 47.7 – q Q68
2020-09-12 09:09:31 C 16 50 10.82 -31 37 30.3 – q E94
2020-09-12 09:19:52 C 16 50 12.50 -31 37 28.9 – q E94
2020-09-12 09:41:25 C 16 50 15.82 -31 37 25.8 – q E94
2020-09-12 09:52:52 C 16 50 17.59 -31 37 23.1 – q E94
2021-07-09 13:30:30 C 23 00 00.084 -07 36 44.96 – U F51
2021-07-09 13:47:40 C 22 59 59.721 -07 36 46.71 – U F51
2021-07-09 14:04:51 C 22 59 59.354 -07 36 48.50 – U F51
2021-07-09 14:22:04 C 22 59 58.986 -07 36 50.24 – U F51
2021-07-11 23:55:17 C 22 58 44.81 -07 43 01.8 – q 215
2021-07-11 23:59:00 C 22 58 44.71 -07 43 02.6 – q 215
2021-07-12 00:02:43 C 22 58 44.57 -07 43 02.3 – q 215
2021-07-13 11:15:19 C 22 57 55.777 -07 47 06.97 – U F51
2021-07-13 11:47:29 C 22 57 54.996 -07 47 10.91 – U F51
2021-07-13 12:04:43 C 22 57 54.574 -07 47 12.93 – U F51
2021-07-19 12:30:59 C 22 54 08.281 -08 06 23.77 – U F51
2021-07-19 12:43:20 C 22 54 07.918 -08 06 25.39 – U F51
2021-07-19 12:56:02 C 22 54 07.546 -08 06 27.38 – U F51
2021-07-31 18:46:16 C 22 44 28.83 -08 55 55.5 – q D29
2021-07-31 19:06:37 C 22 44 28.04 -08 55 59.5 – q D29
2021-07-31 19:26:59 C 22 44 27.32 -08 56 04.6 – q D29
2021-08-04 16:31:44 C 22 40 55.243 -09 14 04.85 – V P07
2021-08-04 17:35:44 C 22 40 52.685 -09 14 17.38 – V P07
2021-08-04 19:55:14 C 22 40 47.129 -09 14 44.52 – V P07
2021-08-04 20:43:19 C 22 40 45.209 -09 14 55.18 – V P07
2021-08-04 21:52:45 C 22 40 42.475 -09 15 07.70 – V P07
2021-08-06 10:50:49 C 22 39 14.888 -09 22 36.85 – U F51
2021-08-06 11:04:00 C 22 39 14.350 -09 22 39.53 – U F51
2021-08-06 11:17:40 C 22 39 13.797 -09 22 42.29 – U F51
2021-08-06 11:30:59 C 22 39 13.252 -09 22 45.00 – U F51
2021-08-07 17:17:20 C 22 38 01.39 -09 28 49.7 – q D29
2021-08-07 17:18:37 C 22 38 01.26 -09 28 50.4 – q D29
2021-08-07 17:37:43 C 22 38 00.53 -09 28 54.1 – q D29
2021-08-07 17:38:59 C 22 38 00.42 -09 28 54.9 – q D29
2021-08-07 17:58:05 C 22 37 59.63 -09 28 57.8 – q D29
2021-08-07 17:59:21 C 22 37 59.60 -09 28 58.7 – q D29
2021-08-10 02:34:44 C 22 35 40.26 -09 40 42.7 – c J04
2021-08-10 02:51:34 C 22 35 39.55 -09 40 46.5 – c J04
2021-08-10 03:08:24 C 22 35 38.86 -09 40 49.7 – c J04
2021-08-10 03:25:14 C 22 35 38.08 -09 40 53.6 – c J04
2021-08-11 15:52:48 C 22 34 06.691 -09 48 30.28 – V P07
2021-08-11 15:54:42 C 22 34 06.643 -09 48 31.03 – V P07
2021-08-11 16:45:28 C 22 34 04.474 -09 48 42.19 – V P07
2021-08-11 18:48:51 C 22 33 59.143 -09 49 08.44 – V P07
2021-08-11 18:53:30 C 22 33 58.939 -09 49 09.26 – V P07
2021-08-12 00:40:46 C 22 33 44.39 -09 50 26.3 – V 204
2021-08-12 00:51:36 C 22 33 43.90 -09 50 28.1 – V 204
2021-08-16 17:01:19 C 22 28 55.15 -10 14 27.1 – q D29
2021-08-16 17:21:40 C 22 28 54.29 -10 14 31.6 – q D29
Radar Observations (2)
Epoch (UTC)ValueSigmaUnitsFreq (MHz)ReceiverTransmitter
1980-11-05 14:44:00 -280334.5 2.5 Hz 2380 -1 -1
1980-11-05.613889 -2803345 10 Hz 2380 251 251
Station codes
-1 Arecibo (305-m, 1963–2020)