C/2020 H4 (Leonard)

メタデータ

項目
Designation C/2020 H4 (Leonard)
Type C
Perihelion (tp_cal, UTC) 2020-08-29T06:41:40.873920Z
Orbit solution date (soln_date, UTC) 2025-01-10T09:12:15Z
Obs used 37
NEO -
M1 16.600
K1 4.500
PC -
Discovery observation (MPC, UTC) 2020-04-21T11:20:52.512000Z
Discovery magnitude (MPC) 19.50 G
Discovery observatory (MPC) G96 · University of Arizona Mt. Lemmon Survey
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2020-04-30.0000000
e 0.99234750
q (au) 0.937676
a (au) 122.531978
i (deg) 84.325459
Ω (om, deg) 307.763404
ω (w, deg) 116.826499
M (ma, deg) 359.911872

等級

C/2020 H4 (Leonard) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (12.688 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 12.688
n 6.000
gf 1.000
gb -1.000
k 0.988
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)
2026-06-01 00:00 06:31:24.94 -67:00:41.6 HIP 31057 8.77
2026-06-01 12:00 06:31:40.09 -67:00:03.1 HIP 31057 8.69
2026-06-02 00:00 06:31:55.29 -66:59:25.2 HIP 31057 8.93
2026-06-02 12:00 06:32:10.54 -66:58:48.1 HIP 31057 9.45
2026-06-03 00:00 06:32:25.83 -66:58:11.6 HIP 31057 10.22
2026-06-03 12:00 06:32:41.17 -66:57:35.9 HIP 31057 11.17
2026-06-04 00:00 06:32:56.55 -66:57:00.9 HIP 31057 12.28
2026-06-04 12:00 06:33:11.98 -66:56:26.6 HIP 31057 13.50
2026-06-05 00:00 06:33:27.45 -66:55:53.1 HIP 31057 14.81
2026-06-05 12:00 06:33:42.97 -66:55:20.2 HIP 31057 16.18
2026-06-06 00:00 06:33:58.52 -66:54:48.1 HIP 31057 17.59
2026-06-06 12:00 06:34:14.12 -66:54:16.7 HIP 31057 19.05
2026-06-07 00:00 06:34:29.76 -66:53:46.0 HIP 31450 20.43
2026-06-07 12:00 06:34:45.44 -66:53:16.0 HIP 31450 20.60
2026-06-08 00:00 06:35:01.15 -66:52:46.8 HIP 31450 20.88
2026-06-08 12:00 06:35:16.91 -66:52:18.3 HIP 31450 21.27
2026-06-09 00:00 06:35:32.70 -66:51:50.5 HIP 31450 21.76
2026-06-09 12:00 06:35:48.53 -66:51:23.5 HIP 31450 22.34
2026-06-10 00:00 06:36:04.39 -66:50:57.2 HIP 31450 23.01
2026-06-10 12:00 06:36:20.29 -66:50:31.7 HIP 31450 23.76
2026-06-11 00:00 06:36:36.23 -66:50:06.8 HIP 31450 24.58
2026-06-11 12:00 06:36:52.20 -66:49:42.7 HIP 31450 25.46
2026-06-12 00:00 06:37:08.20 -66:49:19.4 HIP 31450 26.41
2026-06-12 12:00 06:37:24.23 -66:48:56.8 HIP 31450 27.40
2026-06-13 00:00 06:37:40.29 -66:48:35.0 HIP 31450 28.44
2026-06-13 12:00 06:37:56.38 -66:48:13.8 HIP 31450 29.53
2026-06-14 00:00 06:38:12.50 -66:47:53.5 HIP 31450 30.65
2026-06-14 12:00 06:38:28.65 -66:47:33.9 HIP 31450 31.81
2026-06-15 00:00 06:38:44.83 -66:47:15.0 HIP 32200 32.00
2026-06-15 12:00 06:39:01.03 -66:46:56.9 HIP 32200 30.49
2026-06-16 00:00 06:39:17.26 -66:46:39.6 HIP 32200 29.00
2026-06-16 12:00 06:39:33.51 -66:46:23.0 HIP 32200 27.53
2026-06-17 00:00 06:39:49.79 -66:46:07.1 HIP 32200 26.09
2026-06-17 12:00 06:40:06.09 -66:45:52.0 HIP 32200 24.67
2026-06-18 00:00 06:40:22.41 -66:45:37.7 HIP 32200 23.29
2026-06-18 12:00 06:40:38.75 -66:45:24.1 HIP 32200 21.96
2026-06-19 00:00 06:40:55.11 -66:45:11.3 HIP 32200 20.67
2026-06-19 12:00 06:41:11.49 -66:44:59.2 HIP 32200 19.44
2026-06-20 00:00 06:41:27.88 -66:44:47.9 HIP 32200 18.29
2026-06-20 12:00 06:41:44.30 -66:44:37.4 HIP 32200 17.23
2026-06-21 00:00 06:42:00.73 -66:44:27.6 HIP 32200 16.27
2026-06-21 12:00 06:42:17.18 -66:44:18.5 HIP 32200 15.44
2026-06-22 00:00 06:42:33.64 -66:44:10.3 HIP 32200 14.75