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
2002-10-04 20:58:22 C 22 42 40.04 -04 17 11.7 – c 246
2002-10-04 20:59:28 C 22 42 39.97 -04 17 12.1 – c 246
2002-10-04 21:00:51 C 22 42 39.83 -04 17 12.0 – c 246
2003-07-08 01:24:42 C 01 44 19.35 +17 33 39.3 – c 599
2003-07-08 01:35:43 C 01 44 19.92 +17 33 44.4 – c 599
2003-07-08 01:46:47 C 01 44 20.28 +17 33 47.9 – c 599
2003-07-08 01:58:03 C 01 44 20.73 +17 33 52.4 – c 599
2003-08-03 02:36:29 C 02 08 24.86 +21 32 59.3 – o J95
2003-08-03 02:52:28 C 02 08 25.36 +21 33 04.6 – o J95
2003-08-07 01:24:09 C 02 11 36.36 +22 11 19.4 – c 213
2003-08-07 01:26:59 C 02 11 36.41 +22 11 19.7 – c 213
2003-08-12 02:41:34 C 02 15 26.20 +23 01 33.4 – c 204
2003-08-12 02:46:46 C 02 15 26.30 +23 01 35.8 – c 204
2003-08-12 02:51:59 C 02 15 26.51 +23 01 38.3 – c 204
2003-08-14 02:00:32 C 02 16 50.70 +23 21 34.8 – o 620
2003-08-14 02:24:31 C 02 16 51.40 +23 21 45.4 – o 620
2003-08-20 00:54:14 C 02 20 45.29 +24 23 44.5 – r 213
2003-08-22 23:09:12 C 02 22 27.75 +24 55 19.9 – c 235
2003-08-24 06:49:21 C 02 23 10.30 +25 09 57.5 – m 859
2003-08-24 07:01:24 C 02 23 10.51 +25 10 03.7 – m 859
2003-08-24 07:13:05 C 02 23 10.78 +25 10 11.5 – m 859
2003-08-25 01:59:11 C 02 23 35.36 +25 18 44.9 – c A32
2003-08-25 02:09:46 C 02 23 35.52 +25 18 49.3 – c A32
2003-08-25 09:40:57 C 02 23 45.19 +25 22 18.5 – c 704
2003-08-25 09:58:25 C 02 23 45.62 +25 22 28.1 – c 704
2003-08-25 10:15:51 C 02 23 45.87 +25 22 36.7 – c 704
2003-08-27 00:54:18 C 02 24 33.02 +25 40 41.2 – c 246
2003-08-27 00:55:27 C 02 24 33.04 +25 40 41.6 – c 246
2003-08-27 00:56:51 C 02 24 33.08 +25 40 42.4 – c 246
2003-08-27 00:58:07 C 02 24 33.08 +25 40 42.7 – c 246
2003-08-27 02:47:32 C 02 24 35.16 +25 41 34.5 – c 204
2003-08-27 03:04:05 C 02 24 35.44 +25 41 42.8 – c 204
2003-08-29 23:00:28 C 02 25 49.54 +26 14 16.7 – r 213
2003-08-29 23:05:53 C 02 25 49.54 +26 14 19.5 – r 213
2003-08-29 23:11:17 C 02 25 49.69 +26 14 20.7 – r 213
2003-08-30 23:42:22 C 02 26 13.40 +26 26 22.5 – c 235
2003-08-30 23:57:54 C 02 26 13.61 +26 26 27.7 – c 235
2003-09-01 17:05:29 – 02 26 49.50 +26 46 52.8 – – 372
2003-09-03 15:32:42 C 02 27 24.43 +27 10 23.6 – – 360
2003-09-03 15:40:46 C 02 27 24.52 +27 10 27.8 – – 360
2003-09-03 16:17:30 – 02 27 24.90 +27 10 46.7 – – 372
2003-09-03 21:05:07 C 02 27 28.10 +27 13 12.4 – c 215
2003-09-04 02:12:34 C 02 27 31.27 +27 15 52.8 – c 235
2003-09-05 07:19:31 C 02 27 49.04 +27 31 00.4 – c H41
2003-09-05 07:24:19 C 02 27 48.87 +27 31 01.7 – c H41
2003-09-05 22:54:19 C 02 27 57.04 +27 39 05.8 – d A46
2003-09-05 22:57:32 C 02 27 57.06 +27 39 06.7 – d A46
2003-09-05 23:00:48 C 02 27 57.07 +27 39 09.2 – d A46
2003-09-05 23:08:56 C 02 27 57.14 +27 39 13.3 – d A46
2003-09-05 23:12:09 C 02 27 57.21 +27 39 15.6 – d A46
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)