Comet Archive

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P/2021 HS (PANSTARRS)

メタデータ

項目
Designation P/2021 HS (PANSTARRS)
Type P
Perihelion (tp_cal, UTC) 2021-08-06T09:22:36.661440Z
Orbit solution date (soln_date, UTC) 2021-12-17T03:12:57Z
Obs used 181
NEO Yes
M1 20.600
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2021-07-03.0000000
e 0.81016790
q (au) 0.796446
a (au) 4.195528
i (deg) 12.171396
Ω (om, deg) 262.395858
ω (w, deg) 46.086196
M (ma, deg) 356.055743

等級

P/2021 HS (PANSTARRS) · 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 08:33:42.52 +08:08:53.6 HIP 42049 19.78
2026-02-03 12:00 08:33:27.54 +08:09:49.0 HIP 42049 20.70
2026-02-04 00:00 08:33:12.58 +08:10:44.7 HIP 42049 22.24
2026-02-04 12:00 08:32:57.65 +08:11:40.8 HIP 41840 19.70
2026-02-05 00:00 08:32:42.75 +08:12:37.1 HIP 41840 16.02
2026-02-05 12:00 08:32:27.87 +08:13:33.7 HIP 41840 12.42
2026-02-06 00:00 08:32:13.03 +08:14:30.5 HIP 41840 8.98
2026-02-06 12:00 08:31:58.22 +08:15:27.7 HIP 41840 5.98
2026-02-07 00:00 08:31:43.44 +08:16:25.1 HIP 41840 4.43
2026-02-07 12:00 08:31:28.70 +08:17:22.7 HIP 41840 5.65
2026-02-08 00:00 08:31:14.00 +08:18:20.6 HIP 41840 8.51
2026-02-08 12:00 08:30:59.33 +08:19:18.8 HIP 41840 11.87
2026-02-09 00:00 08:30:44.71 +08:20:17.1 HIP 41840 15.41
2026-02-09 12:00 08:30:30.13 +08:21:15.7 HIP 41652 13.82
2026-02-10 00:00 08:30:15.60 +08:22:14.5 HIP 41652 10.09
2026-02-10 12:00 08:30:01.11 +08:23:13.5 HIP 41652 6.38
2026-02-11 00:00 08:29:46.68 +08:24:12.8 HIP 41652 2.67
2026-02-11 12:00 08:29:32.29 +08:25:12.2 HIP 41652 1.03
2026-02-12 00:00 08:29:17.95 +08:26:11.8 HIP 41652 4.71
2026-02-12 12:00 08:29:03.67 +08:27:11.5 HIP 41652 8.37
2026-02-13 00:00 08:28:49.45 +08:28:11.5 HIP 41652 12.03
2026-02-13 12:00 08:28:35.28 +08:29:11.6 HIP 41652 15.67
2026-02-14 00:00 08:28:21.18 +08:30:11.8 HIP 41652 19.30
2026-02-14 12:00 08:28:07.13 +08:31:12.2 HIP 41652 22.92
2026-02-15 00:00 08:27:53.15 +08:32:12.7 HIP 41652 26.52
2026-02-15 12:00 08:27:39.23 +08:33:13.4 HIP 41652 30.11
2026-02-16 00:00 08:27:25.38 +08:34:14.2 HIP 41652 33.68
2026-02-16 12:00 08:27:11.59 +08:35:15.1 HIP 41652 37.23
2026-02-17 00:00 08:26:57.88 +08:36:16.1 HIP 41340 37.98
2026-02-17 12:00 08:26:44.24 +08:37:17.2 HIP 41204 36.91
2026-02-18 00:00 08:26:30.67 +08:38:18.4 HIP 41204 34.45
2026-02-18 12:00 08:26:17.18 +08:39:19.6 HIP 41204 32.19
2026-02-19 00:00 08:26:03.76 +08:40:20.9 HIP 41204 30.19
2026-02-19 12:00 08:25:50.42 +08:41:22.3 HIP 41204 28.49
2026-02-20 00:00 08:25:37.16 +08:42:23.8 HIP 41204 27.14
2026-02-20 12:00 08:25:23.98 +08:43:25.3 HIP 41204 26.18
2026-02-21 00:00 08:25:10.89 +08:44:26.8 HIP 41204 25.65
2026-02-21 12:00 08:24:57.88 +08:45:28.4 HIP 41204 25.57
2026-02-22 00:00 08:24:44.96 +08:46:30.0 HIP 41150 25.15
2026-02-22 12:00 08:24:32.12 +08:47:31.6 HIP 41150 24.41
2026-02-23 00:00 08:24:19.37 +08:48:33.2 HIP 41150 24.13
2026-02-23 12:00 08:24:06.71 +08:49:34.8 HIP 41150 24.30
2026-02-24 00:00 08:23:54.15 +08:50:36.4 HIP 41183 23.90