Comet Archive

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C/2018 R4 (Fuls)

メタデータ

項目
Designation C/2018 R4 (Fuls)
Type C
Perihelion (tp_cal, UTC) 2018-03-03T15:59:10.642560Z
Orbit solution date (soln_date, UTC) 2022-06-20T23:12:32Z
Obs used 114
NEO -
M1 16.300
K1 4.500
PC -
Discovery observation (MPC, UTC) 2018-09-09T07:28:08.544000Z
Discovery magnitude (MPC) 19.10 G
Discovery observatory (MPC) 703 · Catalina Sky Survey
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2018-09-02.0000000
e 0.99435878
q (au) 1.709214
a (au) 302.986704
i (deg) 11.682034
Ω (om, deg) 298.460925
ω (w, deg) 345.148323
M (ma, deg) 0.034075

等級

C/2018 R4 (Fuls) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (16.140 + 3.866\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 16.140
n 3.866
gf 1.000
gb -0.685
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 04:22:04.78 +30:27:51.5 HIP 20415 4.19
2026-02-03 12:00 04:22:02.74 +30:27:33.3 HIP 20415 4.40
2026-02-04 00:00 04:22:00.75 +30:27:15.3 HIP 20415 4.65
2026-02-04 12:00 04:21:58.82 +30:26:57.4 HIP 20415 4.94
2026-02-05 00:00 04:21:56.95 +30:26:39.5 HIP 20415 5.25
2026-02-05 12:00 04:21:55.13 +30:26:21.7 HIP 20415 5.57
2026-02-06 00:00 04:21:53.37 +30:26:04.1 HIP 20415 5.91
2026-02-06 12:00 04:21:51.67 +30:25:46.5 HIP 20415 6.25
2026-02-07 00:00 04:21:50.02 +30:25:29.0 HIP 20415 6.60
2026-02-07 12:00 04:21:48.44 +30:25:11.6 HIP 20415 6.95
2026-02-08 00:00 04:21:46.91 +30:24:54.3 HIP 20415 7.29
2026-02-08 12:00 04:21:45.43 +30:24:37.1 HIP 20415 7.63
2026-02-09 00:00 04:21:44.02 +30:24:20.0 HIP 20415 7.97
2026-02-09 12:00 04:21:42.66 +30:24:03.0 HIP 20415 8.30
2026-02-10 00:00 04:21:41.36 +30:23:46.1 HIP 20415 8.63
2026-02-10 12:00 04:21:40.11 +30:23:29.3 HIP 20415 8.95
2026-02-11 00:00 04:21:38.93 +30:23:12.6 HIP 20415 9.26
2026-02-11 12:00 04:21:37.80 +30:22:56.0 HIP 20415 9.57
2026-02-12 00:00 04:21:36.73 +30:22:39.5 HIP 20415 9.87
2026-02-12 12:00 04:21:35.72 +30:22:23.2 HIP 20415 10.15
2026-02-13 00:00 04:21:34.77 +30:22:06.9 HIP 20415 10.43
2026-02-13 12:00 04:21:33.88 +30:21:50.8 HIP 20415 10.70
2026-02-14 00:00 04:21:33.04 +30:21:34.7 HIP 20415 10.97
2026-02-14 12:00 04:21:32.26 +30:21:18.8 HIP 20415 11.22
2026-02-15 00:00 04:21:31.54 +30:21:03.0 HIP 20415 11.46
2026-02-15 12:00 04:21:30.88 +30:20:47.3 HIP 20415 11.69
2026-02-16 00:00 04:21:30.28 +30:20:31.8 HIP 20415 11.92
2026-02-16 12:00 04:21:29.73 +30:20:16.3 HIP 20415 12.13
2026-02-17 00:00 04:21:29.24 +30:20:01.0 HIP 20415 12.34
2026-02-17 12:00 04:21:28.81 +30:19:45.8 HIP 20415 12.54
2026-02-18 00:00 04:21:28.44 +30:19:30.7 HIP 20415 12.72
2026-02-18 12:00 04:21:28.13 +30:19:15.8 HIP 20415 12.90
2026-02-19 00:00 04:21:27.88 +30:19:00.9 HIP 20415 13.07
2026-02-19 12:00 04:21:27.68 +30:18:46.2 HIP 20415 13.23
2026-02-20 00:00 04:21:27.54 +30:18:31.6 HIP 20415 13.38
2026-02-20 12:00 04:21:27.46 +30:18:17.2 HIP 20415 13.52
2026-02-21 00:00 04:21:27.44 +30:18:02.9 HIP 20415 13.65
2026-02-21 12:00 04:21:27.47 +30:17:48.7 HIP 20415 13.77
2026-02-22 00:00 04:21:27.57 +30:17:34.6 HIP 20415 13.89
2026-02-22 12:00 04:21:27.72 +30:17:20.7 HIP 20415 13.99
2026-02-23 00:00 04:21:27.93 +30:17:06.9 HIP 20415 14.09
2026-02-23 12:00 04:21:28.19 +30:16:53.2 HIP 20415 14.18
2026-02-24 00:00 04:21:28.51 +30:16:39.7 HIP 20415 14.27