C/2017 K1 (PANSTARRS)

メタデータ

項目
Designation C/2017 K1 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2018-03-14T18:30:37.512000Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:33Z
Obs used 138
NEO -
M1 6.900
K1 10.250
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2018-05-01.0000000
e 1.00209402
q (au) 7.285700
a (au) -3479.295246
i (deg) 154.008296
Ω (om, deg) 225.641843
ω (w, deg) 4.202591
M (ma, deg) 0.000227

等級

C/2017 K1 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (8.144 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 8.144
n 6.000
gf 0.999
gb -0.867
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 08:15:18.89 +45:59:17.0 HIP 40434 7.28
2026-03-26 12:00 08:15:12.69 +45:58:48.3 HIP 40434 7.94
2026-03-27 00:00 08:15:06.58 +45:58:19.2 HIP 40434 8.71
2026-03-27 12:00 08:15:00.55 +45:57:49.8 HIP 40434 9.56
2026-03-28 00:00 08:14:54.60 +45:57:20.2 HIP 40434 10.46
2026-03-28 12:00 08:14:48.73 +45:56:50.2 HIP 40434 11.41
2026-03-29 00:00 08:14:42.94 +45:56:19.9 HIP 40434 12.38
2026-03-29 12:00 08:14:37.24 +45:55:49.4 HIP 40434 13.37
2026-03-30 00:00 08:14:31.62 +45:55:18.5 HIP 40434 14.38
2026-03-30 12:00 08:14:26.07 +45:54:47.4 HIP 40434 15.39
2026-03-31 00:00 08:14:20.61 +45:54:16.0 HIP 40434 16.41
2026-03-31 12:00 08:14:15.24 +45:53:44.3 HIP 40434 17.43
2026-04-01 00:00 08:14:09.94 +45:53:12.4 HIP 40195 17.72
2026-04-01 12:00 08:14:04.73 +45:52:40.2 HIP 40195 17.14
2026-04-02 00:00 08:13:59.60 +45:52:07.7 HIP 40195 16.63
2026-04-02 12:00 08:13:54.55 +45:51:35.0 HIP 40195 16.18
2026-04-03 00:00 08:13:49.58 +45:51:02.0 HIP 40195 15.79
2026-04-03 12:00 08:13:44.70 +45:50:28.7 HIP 40195 15.48
2026-04-04 00:00 08:13:39.90 +45:49:55.2 HIP 40195 15.25
2026-04-04 12:00 08:13:35.18 +45:49:21.5 HIP 40195 15.09
2026-04-05 00:00 08:13:30.54 +45:48:47.5 HIP 40195 15.00
2026-04-05 12:00 08:13:25.99 +45:48:13.3 HIP 40195 15.00
2026-04-06 00:00 08:13:21.51 +45:47:38.8 HIP 40195 15.06
2026-04-06 12:00 08:13:17.12 +45:47:04.1 HIP 40195 15.20
2026-04-07 00:00 08:13:12.82 +45:46:29.2 HIP 40195 15.40
2026-04-07 12:00 08:13:08.59 +45:45:54.1 HIP 40195 15.67
2026-04-08 00:00 08:13:04.45 +45:45:18.7 HIP 40195 16.00
2026-04-08 12:00 08:13:00.39 +45:44:43.1 HIP 40195 16.38
2026-04-09 00:00 08:12:56.42 +45:44:07.4 HIP 40195 16.81
2026-04-09 12:00 08:12:52.52 +45:43:31.4 HIP 40195 17.28
2026-04-10 00:00 08:12:48.71 +45:42:55.1 HIP 40195 17.79
2026-04-10 12:00 08:12:44.98 +45:42:18.7 HIP 40195 18.33
2026-04-11 00:00 08:12:41.34 +45:41:42.1 HIP 40352 18.73
2026-04-11 12:00 08:12:37.77 +45:41:05.3 HIP 40119 18.55
2026-04-12 00:00 08:12:34.29 +45:40:28.3 HIP 40119 17.71
2026-04-12 12:00 08:12:30.90 +45:39:51.2 HIP 40119 16.87
2026-04-13 00:00 08:12:27.58 +45:39:13.8 HIP 40119 16.03
2026-04-13 12:00 08:12:24.35 +45:38:36.3 HIP 40119 15.20
2026-04-14 00:00 08:12:21.20 +45:37:58.5 HIP 40119 14.38
2026-04-14 12:00 08:12:18.13 +45:37:20.6 HIP 40119 13.57
2026-04-15 00:00 08:12:15.14 +45:36:42.6 HIP 40119 12.76
2026-04-15 12:00 08:12:12.24 +45:36:04.3 HIP 40119 11.96
2026-04-16 00:00 08:12:09.41 +45:35:26.0 HIP 40119 11.16