Comet Archive

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D/1977 C1 (Skiff-Kosai)

メタデータ

項目
Designation D/1977 C1 (Skiff-Kosai)
Type D
Perihelion (tp_cal, UTC) 1976-08-03T23:51:26.127360Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:24Z
Obs used 8
NEO -
M1 8.500
K1 15.000
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1977-02-23.0000000
e 0.25917112
q (au) 2.849755
a (au) 3.846712
i (deg) 3.201388
Ω (om, deg) 80.768376
ω (w, deg) 26.550778
M (ma, deg) 26.520292

等級

D/1977 C1 (Skiff-Kosai) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (12.449 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 12.449
n 2.000
gf 1.000
gb -0.502
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 20:48:38.30 -19:51:24.3 HIP 102660 36.26
2026-02-03 12:00 20:49:08.38 -19:49:32.0 HIP 102660 36.29
2026-02-04 00:00 20:49:38.44 -19:47:39.5 HIP 102660 37.76
2026-02-04 12:00 20:50:08.49 -19:45:46.8 HIP 103018 30.88
2026-02-05 00:00 20:50:38.52 -19:43:53.9 HIP 103018 23.57
2026-02-05 12:00 20:51:08.53 -19:42:00.8 HIP 103018 16.26
2026-02-06 00:00 20:51:38.53 -19:40:07.5 HIP 103018 8.97
2026-02-06 12:00 20:52:08.52 -19:38:14.0 HIP 103018 1.82
2026-02-07 00:00 20:52:38.48 -19:36:20.3 HIP 103032 5.23
2026-02-07 12:00 20:53:08.42 -19:34:26.4 HIP 103032 10.00
2026-02-08 00:00 20:53:38.35 -19:32:32.3 HIP 103032 16.71
2026-02-08 12:00 20:54:08.26 -19:30:38.1 HIP 103032 23.77
2026-02-09 00:00 20:54:38.14 -19:28:43.7 HIP 103114 26.87
2026-02-09 12:00 20:55:08.01 -19:26:49.2 HIP 103332 28.26
2026-02-10 00:00 20:55:37.85 -19:24:54.4 HIP 103332 23.81
2026-02-10 12:00 20:56:07.67 -19:22:59.5 HIP 103332 21.02
2026-02-11 00:00 20:56:37.47 -19:21:04.5 HIP 103332 20.57
2026-02-11 12:00 20:57:07.24 -19:19:09.3 HIP 103332 22.59
2026-02-12 00:00 20:57:36.99 -19:17:14.0 HIP 103332 26.53
2026-02-12 12:00 20:58:06.71 -19:15:18.5 HIP 103566 24.23
2026-02-13 00:00 20:58:36.41 -19:13:22.8 HIP 103616 18.05
2026-02-13 12:00 20:59:06.08 -19:11:27.1 HIP 103616 11.73
2026-02-14 00:00 20:59:35.72 -19:09:31.2 HIP 103616 7.41
2026-02-14 12:00 21:00:05.34 -19:07:35.2 HIP 103616 8.81
2026-02-15 00:00 21:00:34.93 -19:05:39.0 HIP 103616 14.33
2026-02-15 12:00 21:01:04.48 -19:03:42.8 HIP 103751 10.10
2026-02-16 00:00 21:01:34.01 -19:01:46.4 HIP 103751 6.96
2026-02-16 12:00 21:02:03.50 -18:59:49.9 HIP 103751 9.99
2026-02-17 00:00 21:02:32.97 -18:57:53.3 HIP 103751 15.99
2026-02-17 12:00 21:03:02.40 -18:55:56.6 HIP 103865 19.41
2026-02-18 00:00 21:03:31.79 -18:53:59.9 HIP 103865 23.65
2026-02-18 12:00 21:04:01.16 -18:52:03.0 HIP 103997 20.86
2026-02-19 00:00 21:04:30.48 -18:50:06.1 HIP 103997 19.13
2026-02-19 12:00 21:04:59.78 -18:48:09.0 HIP 103997 20.01
2026-02-20 00:00 21:05:29.03 -18:46:12.0 HIP 103997 23.21
2026-02-20 12:00 21:05:58.25 -18:44:14.8 HIP 104230 16.32
2026-02-21 00:00 21:06:27.43 -18:42:17.6 HIP 104230 9.27
2026-02-21 12:00 21:06:56.57 -18:40:20.3 HIP 104230 2.94
2026-02-22 00:00 21:07:25.68 -18:38:22.9 HIP 104230 5.85
2026-02-22 12:00 21:07:54.74 -18:36:25.5 HIP 104230 12.74
2026-02-23 00:00 21:08:23.76 -18:34:28.1 HIP 104387 11.06
2026-02-23 12:00 21:08:52.74 -18:32:30.6 HIP 104387 11.14
2026-02-24 00:00 21:09:21.68 -18:30:33.1 HIP 104387 15.09