Comet Archive

Clear skies!

C/1987 H1 (Shoemaker)

メタデータ

項目
Designation C/1987 H1 (Shoemaker)
Type C
Perihelion (tp_cal, UTC) 1986-11-17T00:37:43.749120Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:33Z
Obs used 126
NEO -
M1 5.200
K1 9.750
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1987-11-03.0000000
e 1.00321165
q (au) 5.457290
a (au) -1699.216266
i (deg) 132.485156
Ω (om, deg) 268.336619
ω (w, deg) 16.992162
M (ma, deg) 0.004939

等級

C/1987 H1 (Shoemaker) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (2.864 + 5.022\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 2.864
n 5.022
gf 0.980
gb -1.000
k 1.000
δ90 9.814
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 06:50:14.87 +36:32:21.3 HIP 32798 8.24
2026-02-03 12:00 06:50:12.64 +36:32:18.6 HIP 32798 8.20
2026-02-04 00:00 06:50:10.42 +36:32:15.8 HIP 32798 8.18
2026-02-04 12:00 06:50:08.22 +36:32:12.9 HIP 32798 8.18
2026-02-05 00:00 06:50:06.02 +36:32:10.0 HIP 32728 7.97
2026-02-05 12:00 06:50:03.84 +36:32:07.0 HIP 32728 7.63
2026-02-06 00:00 06:50:01.67 +36:32:03.9 HIP 32728 7.30
2026-02-06 12:00 06:49:59.52 +36:32:00.8 HIP 32728 6.99
2026-02-07 00:00 06:49:57.38 +36:31:57.6 HIP 32728 6.69
2026-02-07 12:00 06:49:55.25 +36:31:54.3 HIP 32728 6.40
2026-02-08 00:00 06:49:53.14 +36:31:51.0 HIP 32728 6.14
2026-02-08 12:00 06:49:51.04 +36:31:47.6 HIP 32728 5.89
2026-02-09 00:00 06:49:48.95 +36:31:44.2 HIP 32728 5.66
2026-02-09 12:00 06:49:46.88 +36:31:40.7 HIP 32728 5.46
2026-02-10 00:00 06:49:44.82 +36:31:37.1 HIP 32728 5.29
2026-02-10 12:00 06:49:42.78 +36:31:33.4 HIP 32728 5.14
2026-02-11 00:00 06:49:40.75 +36:31:29.7 HIP 32728 5.02
2026-02-11 12:00 06:49:38.73 +36:31:26.0 HIP 32728 4.93
2026-02-12 00:00 06:49:36.73 +36:31:22.1 HIP 32728 4.87
2026-02-12 12:00 06:49:34.75 +36:31:18.3 HIP 32728 4.84
2026-02-13 00:00 06:49:32.78 +36:31:14.3 HIP 32728 4.85
2026-02-13 12:00 06:49:30.82 +36:31:10.3 HIP 32728 4.89
2026-02-14 00:00 06:49:28.88 +36:31:06.2 HIP 32728 4.96
2026-02-14 12:00 06:49:26.96 +36:31:02.1 HIP 32728 5.05
2026-02-15 00:00 06:49:25.05 +36:30:57.9 HIP 32728 5.17
2026-02-15 12:00 06:49:23.16 +36:30:53.6 HIP 32728 5.32
2026-02-16 00:00 06:49:21.28 +36:30:49.3 HIP 32728 5.48
2026-02-16 12:00 06:49:19.42 +36:30:44.9 HIP 32728 5.67
2026-02-17 00:00 06:49:17.58 +36:30:40.5 HIP 32728 5.87
2026-02-17 12:00 06:49:15.75 +36:30:36.0 HIP 32728 6.08
2026-02-18 00:00 06:49:13.94 +36:30:31.4 HIP 32728 6.30
2026-02-18 12:00 06:49:12.15 +36:30:26.8 HIP 32728 6.54
2026-02-19 00:00 06:49:10.37 +36:30:22.1 HIP 32728 6.78
2026-02-19 12:00 06:49:08.61 +36:30:17.4 HIP 32728 7.03
2026-02-20 00:00 06:49:06.87 +36:30:12.6 HIP 32728 7.29
2026-02-20 12:00 06:49:05.14 +36:30:07.8 HIP 32728 7.55
2026-02-21 00:00 06:49:03.43 +36:30:02.9 HIP 32728 7.82
2026-02-21 12:00 06:49:01.74 +36:29:57.9 HIP 32728 8.09
2026-02-22 00:00 06:49:00.07 +36:29:52.9 HIP 32728 8.36
2026-02-22 12:00 06:48:58.41 +36:29:47.8 HIP 32728 8.63
2026-02-23 00:00 06:48:56.78 +36:29:42.7 HIP 32728 8.91
2026-02-23 12:00 06:48:55.16 +36:29:37.5 HIP 32728 9.18
2026-02-24 00:00 06:48:53.55 +36:29:32.3 HIP 32728 9.46