C/2020 K3 (Leonard)

メタデータ

項目
Designation C/2020 K3 (Leonard)
Type C
Perihelion (tp_cal, UTC) 2020-05-30T02:55:42.355200Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:34:07Z
Obs used 212
NEO -
M1 14.900
K1 13.000
PC 0.030
Discovery observation (MPC, UTC) 2020-05-22T10:46:25.824000Z
Discovery magnitude (MPC) 18.00 G
Discovery observatory (MPC) 703 · University of Arizona Catalina Sky Survey
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2020-06-08.0000000
e 0.99242187
q (au) 1.593446
a (au) 210.269034
i (deg) 128.715444
Ω (om, deg) 27.927767
ω (w, deg) 62.697775
M (ma, deg) 0.002870

等級

C/2020 K3 (Leonard) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (15.248 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 15.248
n 6.000
gf 1.000
gb -0.656
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

残差 (区間線形)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

開始日 (UTC) 終了日 (UTC) a b
2019-10-25 2020-05-29 +3.6819 -1.535
2020-05-31 2020-09-12 +12.6466 -2.959

log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-07-29 00:00 11:48:19.42 -21:39:03.4 HIP 57468 23.52
2026-07-29 12:00 11:48:22.94 -21:39:01.4 HIP 57468 24.24
2026-07-30 00:00 11:48:26.50 -21:38:59.8 HIP 57468 24.97
2026-07-30 12:00 11:48:30.10 -21:38:58.6 HIP 57468 25.73
2026-07-31 00:00 11:48:33.73 -21:38:57.9 HIP 57468 26.50
2026-07-31 12:00 11:48:37.41 -21:38:57.6 HIP 57468 27.28
2026-08-01 00:00 11:48:41.12 -21:38:57.7 HIP 57468 28.08
2026-08-01 12:00 11:48:44.86 -21:38:58.3 HIP 57468 28.90
2026-08-02 00:00 11:48:48.65 -21:38:59.3 HIP 57583 29.64
2026-08-02 12:00 11:48:52.47 -21:39:00.7 HIP 57583 29.87
2026-08-03 00:00 11:48:56.33 -21:39:02.6 HIP 57583 30.11
2026-08-03 12:00 11:49:00.22 -21:39:04.9 HIP 57583 30.37
2026-08-04 00:00 11:49:04.15 -21:39:07.7 HIP 57583 30.66
2026-08-04 12:00 11:49:08.11 -21:39:10.8 HIP 57583 30.96
2026-08-05 00:00 11:49:12.11 -21:39:14.4 HIP 57717 31.15
2026-08-05 12:00 11:49:16.15 -21:39:18.5 HIP 57717 30.81
2026-08-06 00:00 11:49:20.21 -21:39:23.0 HIP 57717 30.50
2026-08-06 12:00 11:49:24.32 -21:39:27.9 HIP 57827 29.89
2026-08-07 00:00 11:49:28.45 -21:39:33.2 HIP 57827 28.94
2026-08-07 12:00 11:49:32.62 -21:39:39.0 HIP 57827 27.98
2026-08-08 00:00 11:49:36.82 -21:39:45.2 HIP 57827 27.01
2026-08-08 12:00 11:49:41.06 -21:39:51.8 HIP 57827 26.03
2026-08-09 00:00 11:49:45.33 -21:39:58.9 HIP 57827 25.05
2026-08-09 12:00 11:49:49.62 -21:40:06.3 HIP 57827 24.06
2026-08-10 00:00 11:49:53.96 -21:40:14.3 HIP 57827 23.07
2026-08-10 12:00 11:49:58.32 -21:40:22.6 HIP 57827 22.08
2026-08-11 00:00 11:50:02.71 -21:40:31.4 HIP 57827 21.08
2026-08-11 12:00 11:50:07.14 -21:40:40.6 HIP 57827 20.07
2026-08-12 00:00 11:50:11.59 -21:40:50.2 HIP 57827 19.07
2026-08-12 12:00 11:50:16.08 -21:41:00.2 HIP 57827 18.06
2026-08-13 00:00 11:50:20.59 -21:41:10.7 HIP 57827 17.06
2026-08-13 12:00 11:50:25.13 -21:41:21.6 HIP 57827 16.06
2026-08-14 00:00 11:50:29.70 -21:41:32.9 HIP 57827 15.06
2026-08-14 12:00 11:50:34.31 -21:41:44.7 HIP 57827 14.07
2026-08-15 00:00 11:50:38.93 -21:41:56.8 HIP 57827 13.09
2026-08-15 12:00 11:50:43.59 -21:42:09.4 HIP 57827 12.13
2026-08-16 00:00 11:50:48.27 -21:42:22.4 HIP 57827 11.18
2026-08-16 12:00 11:50:52.98 -21:42:35.8 HIP 57827 10.27
2026-08-17 00:00 11:50:57.72 -21:42:49.6 HIP 57827 9.41
2026-08-17 12:00 11:51:02.48 -21:43:03.8 HIP 57827 8.60
2026-08-18 00:00 11:51:07.27 -21:43:18.5 HIP 57827 7.87
2026-08-18 12:00 11:51:12.08 -21:43:33.5 HIP 57827 7.25
2026-08-19 00:00 11:51:16.92 -21:43:49.0 HIP 57827 6.77