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2P/Encke

メタデータ

項目
Designation 2P/Encke
Type P
Perihelion (tp_cal, UTC) 2023-10-22T03:35:18.398400Z
Orbit solution date (soln_date, UTC) 2025-12-15T09:34:26Z
Obs used 640
NEO Yes
M1 15.600
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2022-09-25.0000000
e 0.84774970
q (au) 0.337948
a (au) 2.219689
i (deg) 11.412278
Ω (om, deg) 334.193585
ω (w, deg) 187.134246
M (ma, deg) 243.126069

等級

2P/Encke · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (13.799 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 13.799
n 2.000
gf 1.000
gb -1.000
k 1.000
δ90 10.000
パラメータ 記号 範囲 説明
太陽・地球距離が1 AUのときの絶対等級 H0 -5 to 20 彗星の固有の明るさ
測光スロープパラメータ n 2 to 6 太陽距離に対する明るさ変化率
前方散乱非対称係数 gf 0.8 to 1 前方散乱の強さ
後方散乱非対称係数 gb -1 to -0.5 後方散乱の強さ
分配係数 k 0.8 to 1 前方/後方散乱の寄与比
ダスト/ガス明るさ比 δ90 1 to 10 ダスト散乱とガス放射の相対寄与

参考: EPSC-DPS2025-160

ファインディングチャート

2P/Encke · Next 30 Days

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 22:58:36.23 -03:19:17.1 HIP 113355 20.13
2026-02-03 12:00 22:59:01.59 -03:16:34.0 HIP 113523 24.43
2026-02-04 00:00 22:59:27.03 -03:13:50.3 HIP 113523 20.71
2026-02-04 12:00 22:59:52.54 -03:11:05.9 HIP 113523 18.88
2026-02-05 00:00 23:00:18.12 -03:08:20.9 HIP 113555 17.61
2026-02-05 12:00 23:00:43.77 -03:05:35.1 HIP 113555 18.07
2026-02-06 00:00 23:01:09.50 -03:02:48.7 HIP 113555 20.99
2026-02-06 12:00 23:01:35.29 -03:00:01.7 HIP 113727 19.52
2026-02-07 00:00 23:02:01.15 -02:57:14.0 HIP 113727 16.14
2026-02-07 12:00 23:02:27.09 -02:54:25.7 HIP 113727 15.45
2026-02-08 00:00 23:02:53.08 -02:51:36.7 HIP 113727 17.80
2026-02-08 12:00 23:03:19.15 -02:48:47.1 HIP 113727 22.26
2026-02-09 00:00 23:03:45.28 -02:45:56.9 HIP 113727 27.85
2026-02-09 12:00 23:04:11.48 -02:43:06.0 HIP 113727 34.04
2026-02-10 00:00 23:04:37.75 -02:40:14.5 HIP 113727 40.55
2026-02-10 12:00 23:05:04.07 -02:37:22.4 HIP 113931 44.85
2026-02-11 00:00 23:05:30.46 -02:34:29.6 HIP 114202 43.00
2026-02-11 12:00 23:05:56.92 -02:31:36.2 HIP 114202 36.18
2026-02-12 00:00 23:06:23.44 -02:28:42.3 HIP 114202 29.53
2026-02-12 12:00 23:06:50.01 -02:25:47.7 HIP 114202 23.20
2026-02-13 00:00 23:07:16.65 -02:22:52.5 HIP 114202 17.59
2026-02-13 12:00 23:07:43.35 -02:19:56.7 HIP 114202 13.64
2026-02-14 00:00 23:08:10.11 -02:17:00.4 HIP 114202 12.99
2026-02-14 12:00 23:08:36.93 -02:14:03.4 HIP 114322 8.50
2026-02-15 00:00 23:09:03.80 -02:11:05.9 HIP 114322 4.82
2026-02-15 12:00 23:09:30.74 -02:08:07.7 HIP 114322 9.07
2026-02-16 00:00 23:09:57.72 -02:05:09.0 HIP 114322 15.81
2026-02-16 12:00 23:10:24.77 -02:02:09.8 HIP 114322 22.96
2026-02-17 00:00 23:10:51.87 -01:59:09.9 HIP 114551 20.58
2026-02-17 12:00 23:11:19.02 -01:56:09.6 HIP 114551 15.03
2026-02-18 00:00 23:11:46.23 -01:53:08.6 HIP 114551 11.75
2026-02-18 12:00 23:12:13.49 -01:50:07.1 HIP 114551 12.70
2026-02-19 00:00 23:12:40.80 -01:47:05.1 HIP 114551 17.20
2026-02-19 12:00 23:13:08.16 -01:44:02.5 HIP 114618 19.72
2026-02-20 00:00 23:13:35.57 -01:40:59.4 HIP 114618 23.46
2026-02-20 12:00 23:14:03.03 -01:37:55.7 HIP 114618 28.73
2026-02-21 00:00 23:14:30.54 -01:34:51.5 HIP 114864 23.87
2026-02-21 12:00 23:14:58.10 -01:31:46.9 HIP 114864 16.33
2026-02-22 00:00 23:15:25.70 -01:28:41.7 HIP 114864 8.78
2026-02-22 12:00 23:15:53.35 -01:25:35.9 HIP 114864 1.25
2026-02-23 00:00 23:16:21.05 -01:22:29.7 HIP 114864 6.40
2026-02-23 12:00 23:16:48.79 -01:19:23.0 HIP 114864 13.99
2026-02-24 00:00 23:17:16.58 -01:16:15.8 HIP 115012 15.91