C/1990 K1 (Levy)

メタデータ

項目
Designation C/1990 K1 (Levy)
Type C
Perihelion (tp_cal, UTC) 1990-10-24T16:24:53.331840Z
Orbit solution date (soln_date, UTC) 2023-08-19T20:42:31Z
Obs used 666
NEO -
M1 4.600
K1 9.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1990-10-29.0000000
e 1.00058309
q (au) 0.938738
a (au) -1609.945375
i (deg) 131.583977
Ω (om, deg) 139.364097
ω (w, deg) 242.666331
M (ma, deg) 0.000066

等級

C/1990 K1 (Levy) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (4.561 + 3.402\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 4.561
n 3.402
gf 0.800
gb -0.500
k 0.916
δ90 1.000
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
1990-05-20 1990-07-17 +0.5628 -0.382
1990-07-17 1990-10-23 -2.7920 +0.454
1990-10-24 1991-04-15 +1.4645 +0.190
1991-04-15 1991-11-07 -5.2198 +3.605

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 07:20:38.80 +55:49:46.0 HIP 35530 27.10
2026-07-29 12:00 07:20:41.94 +55:49:48.2 HIP 35530 27.16
2026-07-30 00:00 07:20:45.08 +55:49:50.5 HIP 35530 27.22
2026-07-30 12:00 07:20:48.21 +55:49:53.0 HIP 35530 27.29
2026-07-31 00:00 07:20:51.32 +55:49:55.6 HIP 35530 27.37
2026-07-31 12:00 07:20:54.43 +55:49:58.3 HIP 35530 27.45
2026-08-01 00:00 07:20:57.53 +55:50:01.1 HIP 35530 27.53
2026-08-01 12:00 07:21:00.62 +55:50:04.1 HIP 35530 27.62
2026-08-02 00:00 07:21:03.70 +55:50:07.2 HIP 35530 27.71
2026-08-02 12:00 07:21:06.77 +55:50:10.5 HIP 35530 27.80
2026-08-03 00:00 07:21:09.84 +55:50:13.8 HIP 35530 27.90
2026-08-03 12:00 07:21:12.89 +55:50:17.3 HIP 35530 28.01
2026-08-04 00:00 07:21:15.93 +55:50:20.9 HIP 35530 28.11
2026-08-04 12:00 07:21:18.96 +55:50:24.7 HIP 35530 28.22
2026-08-05 00:00 07:21:21.98 +55:50:28.6 HIP 35530 28.33
2026-08-05 12:00 07:21:24.99 +55:50:32.6 HIP 35530 28.45
2026-08-06 00:00 07:21:27.99 +55:50:36.8 HIP 35530 28.57
2026-08-06 12:00 07:21:30.97 +55:50:41.0 HIP 35530 28.69
2026-08-07 00:00 07:21:33.95 +55:50:45.4 HIP 35530 28.82
2026-08-07 12:00 07:21:36.91 +55:50:50.0 HIP 35530 28.95
2026-08-08 00:00 07:21:39.87 +55:50:54.6 HIP 35530 29.08
2026-08-08 12:00 07:21:42.81 +55:50:59.4 HIP 35530 29.22
2026-08-09 00:00 07:21:45.74 +55:51:04.4 HIP 35530 29.35
2026-08-09 12:00 07:21:48.65 +55:51:09.4 HIP 35530 29.49
2026-08-10 00:00 07:21:51.55 +55:51:14.6 HIP 35530 29.63
2026-08-10 12:00 07:21:54.44 +55:51:19.9 HIP 35530 29.78
2026-08-11 00:00 07:21:57.32 +55:51:25.4 HIP 35530 29.93
2026-08-11 12:00 07:22:00.18 +55:51:30.9 HIP 35530 30.07
2026-08-12 00:00 07:22:03.03 +55:51:36.6 HIP 35530 30.22
2026-08-12 12:00 07:22:05.87 +55:51:42.5 HIP 35530 30.38
2026-08-13 00:00 07:22:08.69 +55:51:48.4 HIP 35530 30.53
2026-08-13 12:00 07:22:11.49 +55:51:54.5 HIP 35530 30.69
2026-08-14 00:00 07:22:14.29 +55:52:00.7 HIP 35530 30.84
2026-08-14 12:00 07:22:17.06 +55:52:07.0 HIP 35530 31.00
2026-08-15 00:00 07:22:19.83 +55:52:13.5 HIP 35530 31.16
2026-08-15 12:00 07:22:22.57 +55:52:20.1 HIP 35530 31.32
2026-08-16 00:00 07:22:25.31 +55:52:26.8 HIP 35530 31.49
2026-08-16 12:00 07:22:28.02 +55:52:33.6 HIP 35530 31.65
2026-08-17 00:00 07:22:30.72 +55:52:40.6 HIP 35530 31.81
2026-08-17 12:00 07:22:33.41 +55:52:47.7 HIP 35530 31.98
2026-08-18 00:00 07:22:36.08 +55:52:54.9 HIP 35530 32.15
2026-08-18 12:00 07:22:38.73 +55:53:02.3 HIP 35530 32.31
2026-08-19 00:00 07:22:41.37 +55:53:09.7 HIP 35530 32.48