Comet Archive

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C/2012 E2 (SWAN)

メタデータ

項目
Designation C/2012 E2 (SWAN)
Type C
Perihelion (tp_cal, UTC) 2012-03-15T00:41:51.241920Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:32:04Z
Obs used 43
NEO -
M1 -
K1 -
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2012-03-13.0000000
e 1.00049131
q (au) 0.006962
a (au) -14.169573
i (deg) 144.430741
Ω (om, deg) 6.576461
ω (w, deg) 82.412294
M (ma, deg) -0.037494

等級

C/2012 E2 (SWAN) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 -
n -
gf -
gb -
k -
δ90 -
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 06:59:25.52 -13:10:32.2 HIP 33664 10.72
2026-02-03 12:00 06:59:22.77 -13:10:15.0 HIP 33664 10.63
2026-02-04 00:00 06:59:20.03 -13:09:57.7 HIP 33664 10.58
2026-02-04 12:00 06:59:17.31 -13:09:40.1 HIP 33664 10.58
2026-02-05 00:00 06:59:14.60 -13:09:22.4 HIP 33664 10.62
2026-02-05 12:00 06:59:11.91 -13:09:04.5 HIP 33664 10.71
2026-02-06 00:00 06:59:09.23 -13:08:46.4 HIP 33664 10.84
2026-02-06 12:00 06:59:06.57 -13:08:28.1 HIP 33664 11.01
2026-02-07 00:00 06:59:03.92 -13:08:09.7 HIP 33664 11.22
2026-02-07 12:00 06:59:01.30 -13:07:51.0 HIP 33664 11.47
2026-02-08 00:00 06:58:58.68 -13:07:32.3 HIP 33560 11.32
2026-02-08 12:00 06:58:56.09 -13:07:13.3 HIP 33560 10.65
2026-02-09 00:00 06:58:53.51 -13:06:54.2 HIP 33560 9.99
2026-02-09 12:00 06:58:50.95 -13:06:34.9 HIP 33560 9.34
2026-02-10 00:00 06:58:48.41 -13:06:15.4 HIP 33560 8.69
2026-02-10 12:00 06:58:45.89 -13:05:55.8 HIP 33560 8.06
2026-02-11 00:00 06:58:43.38 -13:05:36.0 HIP 33560 7.43
2026-02-11 12:00 06:58:40.89 -13:05:16.0 HIP 33560 6.82
2026-02-12 00:00 06:58:38.42 -13:04:55.9 HIP 33560 6.23
2026-02-12 12:00 06:58:35.97 -13:04:35.6 HIP 33560 5.65
2026-02-13 00:00 06:58:33.53 -13:04:15.2 HIP 33560 5.10
2026-02-13 12:00 06:58:31.12 -13:03:54.6 HIP 33560 4.59
2026-02-14 00:00 06:58:28.72 -13:03:33.9 HIP 33560 4.13
2026-02-14 12:00 06:58:26.35 -13:03:13.0 HIP 33560 3.73
2026-02-15 00:00 06:58:23.99 -13:02:52.0 HIP 33560 3.41
2026-02-15 12:00 06:58:21.65 -13:02:30.8 HIP 33560 3.21
2026-02-16 00:00 06:58:19.34 -13:02:09.4 HIP 33560 3.13
2026-02-16 12:00 06:58:17.04 -13:01:48.0 HIP 33560 3.18
2026-02-17 00:00 06:58:14.76 -13:01:26.4 HIP 33560 3.37
2026-02-17 12:00 06:58:12.51 -13:01:04.6 HIP 33560 3.65
2026-02-18 00:00 06:58:10.27 -13:00:42.7 HIP 33560 4.03
2026-02-18 12:00 06:58:08.05 -13:00:20.7 HIP 33560 4.46
2026-02-19 00:00 06:58:05.86 -12:59:58.5 HIP 33560 4.93
2026-02-19 12:00 06:58:03.69 -12:59:36.3 HIP 33560 5.44
2026-02-20 00:00 06:58:01.53 -12:59:13.8 HIP 33560 5.97
2026-02-20 12:00 06:57:59.40 -12:58:51.3 HIP 33560 6.51
2026-02-21 00:00 06:57:57.29 -12:58:28.6 HIP 33560 7.07
2026-02-21 12:00 06:57:55.21 -12:58:05.9 HIP 33560 7.63
2026-02-22 00:00 06:57:53.14 -12:57:42.9 HIP 33560 8.20
2026-02-22 12:00 06:57:51.10 -12:57:19.9 HIP 33560 8.78
2026-02-23 00:00 06:57:49.07 -12:56:56.8 HIP 33560 9.35
2026-02-23 12:00 06:57:47.08 -12:56:33.5 HIP 33560 9.93
2026-02-24 00:00 06:57:45.10 -12:56:10.2 HIP 33560 10.51