C/2018 R4 (Fuls)

メタデータ

項目 値
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 · University of Arizona Catalina Sky Survey
オスキュレーティング軌道要素
項目 値
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

$$ M_a = (16.140 + 3.865\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目 値
H0 16.140
n 3.865
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)
2026-09-20 00:00 04:49:52.43 +31:06:24.9 HIP 22375 13.98
2026-09-20 12:00 04:49:51.36 +31:06:34.2 HIP 22375 13.89
2026-09-21 00:00 04:49:50.23 +31:06:43.4 HIP 22375 13.79
2026-09-21 12:00 04:49:49.05 +31:06:52.5 HIP 22375 13.69
2026-09-22 00:00 04:49:47.81 +31:07:01.5 HIP 22375 13.59
2026-09-22 12:00 04:49:46.52 +31:07:10.3 HIP 22375 13.49
2026-09-23 00:00 04:49:45.18 +31:07:19.1 HIP 22375 13.38
2026-09-23 12:00 04:49:43.79 +31:07:27.8 HIP 22375 13.26
2026-09-24 00:00 04:49:42.34 +31:07:36.3 HIP 22375 13.15
2026-09-24 12:00 04:49:40.84 +31:07:44.8 HIP 22375 13.04
2026-09-25 00:00 04:49:39.28 +31:07:53.1 HIP 22375 12.92
2026-09-25 12:00 04:49:37.68 +31:08:01.4 HIP 22375 12.81
2026-09-26 00:00 04:49:36.02 +31:08:09.5 HIP 22375 12.70
2026-09-26 12:00 04:49:34.31 +31:08:17.5 HIP 22375 12.59
2026-09-27 00:00 04:49:32.55 +31:08:25.4 HIP 22375 12.48
2026-09-27 12:00 04:49:30.73 +31:08:33.2 HIP 22375 12.38
2026-09-28 00:00 04:49:28.86 +31:08:40.9 HIP 22375 12.29
2026-09-28 12:00 04:49:26.95 +31:08:48.4 HIP 22375 12.20
2026-09-29 00:00 04:49:24.97 +31:08:55.9 HIP 22375 12.11
2026-09-29 12:00 04:49:22.95 +31:09:03.2 HIP 22375 12.04
2026-09-30 00:00 04:49:20.88 +31:09:10.4 HIP 22375 11.98
2026-09-30 12:00 04:49:18.75 +31:09:17.5 HIP 22375 11.93
2026-10-01 00:00 04:49:16.57 +31:09:24.5 HIP 22375 11.90
2026-10-01 12:00 04:49:14.34 +31:09:31.3 HIP 22375 11.87
2026-10-02 00:00 04:49:12.06 +31:09:38.1 HIP 22375 11.87
2026-10-02 12:00 04:49:09.73 +31:09:44.7 HIP 22375 11.88
2026-10-03 00:00 04:49:07.35 +31:09:51.2 HIP 22375 11.91
2026-10-03 12:00 04:49:04.91 +31:09:57.5 HIP 22375 11.96
2026-10-04 00:00 04:49:02.43 +31:10:03.8 HIP 22375 12.03
2026-10-04 12:00 04:48:59.89 +31:10:09.9 HIP 22375 12.12
2026-10-05 00:00 04:48:57.30 +31:10:15.9 HIP 22375 12.24
2026-10-05 12:00 04:48:54.67 +31:10:21.8 HIP 22375 12.38
2026-10-06 00:00 04:48:51.98 +31:10:27.5 HIP 22375 12.54
2026-10-06 12:00 04:48:49.24 +31:10:33.1 HIP 22375 12.73
2026-10-07 00:00 04:48:46.45 +31:10:38.6 HIP 22375 12.94
2026-10-07 12:00 04:48:43.62 +31:10:43.9 HIP 22375 13.18
2026-10-08 00:00 04:48:40.73 +31:10:49.1 HIP 22375 13.44
2026-10-08 12:00 04:48:37.79 +31:10:54.2 HIP 22375 13.73
2026-10-09 00:00 04:48:34.81 +31:10:59.2 HIP 22375 14.04
2026-10-09 12:00 04:48:31.78 +31:11:04.0 HIP 22375 14.38
2026-10-10 00:00 04:48:28.69 +31:11:08.7 HIP 22375 14.74
2026-10-10 12:00 04:48:25.56 +31:11:13.2 HIP 22375 15.12
2026-10-11 00:00 04:48:22.38 +31:11:17.6 HIP 22375 15.53