C/2015 C2 (SWAN)

メタデータ

項目
Designation C/2015 C2 (SWAN)
Type C
Perihelion (tp_cal, UTC) 2015-03-04T13:33:59.673600Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:06Z
Obs used 151
NEO -
M1 12.700
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2015-04-26.0000000
e 0.99851030
q (au) 0.711377
a (au) 477.531702
i (deg) 94.501074
Ω (om, deg) 49.529700
ω (w, deg) 334.134062
M (ma, deg) 0.004952

等級

C/2015 C2 (SWAN) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (14.217 + 3.643\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 14.217
n 3.643
gf 1.000
gb -1.000
k 0.800
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-03-26 00:00 16:17:28.77 +24:35:51.3 HIP 79930 20.23
2026-03-26 12:00 16:17:26.37 +24:36:34.6 HIP 79930 21.01
2026-03-27 00:00 16:17:23.93 +24:37:17.9 HIP 79930 21.80
2026-03-27 12:00 16:17:21.45 +24:38:01.0 HIP 79930 22.61
2026-03-28 00:00 16:17:18.94 +24:38:43.9 HIP 79930 23.44
2026-03-28 12:00 16:17:16.39 +24:39:26.7 HIP 79930 24.27
2026-03-29 00:00 16:17:13.81 +24:40:09.3 HIP 79930 25.12
2026-03-29 12:00 16:17:11.18 +24:40:51.8 HIP 79930 25.98
2026-03-30 00:00 16:17:08.53 +24:41:34.1 HIP 79930 26.85
2026-03-30 12:00 16:17:05.83 +24:42:16.3 HIP 79930 27.73
2026-03-31 00:00 16:17:03.10 +24:42:58.3 HIP 79930 28.62
2026-03-31 12:00 16:17:00.34 +24:43:40.1 HIP 79639 28.39
2026-04-01 00:00 16:16:57.54 +24:44:21.8 HIP 79639 28.12
2026-04-01 12:00 16:16:54.70 +24:45:03.2 HIP 79639 27.87
2026-04-02 00:00 16:16:51.83 +24:45:44.5 HIP 79639 27.65
2026-04-02 12:00 16:16:48.93 +24:46:25.6 HIP 79639 27.44
2026-04-03 00:00 16:16:45.99 +24:47:06.6 HIP 79639 27.27
2026-04-03 12:00 16:16:43.02 +24:47:47.3 HIP 79639 27.11
2026-04-04 00:00 16:16:40.01 +24:48:27.8 HIP 79639 26.98
2026-04-04 12:00 16:16:36.97 +24:49:08.2 HIP 79639 26.88
2026-04-05 00:00 16:16:33.89 +24:49:48.3 HIP 79639 26.80
2026-04-05 12:00 16:16:30.79 +24:50:28.3 HIP 79639 26.75
2026-04-06 00:00 16:16:27.65 +24:51:08.0 HIP 79639 26.73
2026-04-06 12:00 16:16:24.47 +24:51:47.5 HIP 79639 26.74
2026-04-07 00:00 16:16:21.27 +24:52:26.8 HIP 79639 26.77
2026-04-07 12:00 16:16:18.03 +24:53:05.9 HIP 79639 26.83
2026-04-08 00:00 16:16:14.76 +24:53:44.8 HIP 79639 26.93
2026-04-08 12:00 16:16:11.45 +24:54:23.5 HIP 79639 27.05
2026-04-09 00:00 16:16:08.12 +24:55:01.9 HIP 79639 27.19
2026-04-09 12:00 16:16:04.75 +24:55:40.1 HIP 79639 27.37
2026-04-10 00:00 16:16:01.35 +24:56:18.1 HIP 79639 27.58
2026-04-10 12:00 16:15:57.92 +24:56:55.8 HIP 79639 27.81
2026-04-11 00:00 16:15:54.47 +24:57:33.3 HIP 79639 28.07
2026-04-11 12:00 16:15:50.98 +24:58:10.5 HIP 79639 28.36
2026-04-12 00:00 16:15:47.45 +24:58:47.5 HIP 79639 28.67
2026-04-12 12:00 16:15:43.90 +24:59:24.3 HIP 79639 29.01
2026-04-13 00:00 16:15:40.32 +25:00:00.8 HIP 79639 29.38
2026-04-13 12:00 16:15:36.71 +25:00:37.0 HIP 79639 29.77
2026-04-14 00:00 16:15:33.08 +25:01:13.0 HIP 79639 30.18
2026-04-14 12:00 16:15:29.41 +25:01:48.7 HIP 79510 30.12
2026-04-15 00:00 16:15:25.71 +25:02:24.2 HIP 79510 29.11
2026-04-15 12:00 16:15:21.99 +25:02:59.4 HIP 79510 28.10
2026-04-16 00:00 16:15:18.23 +25:03:34.3 HIP 79510 27.09