C/2021 Q4 (Fuls)

メタデータ

項目 値
Designation C/2021 Q4 (Fuls)
Type C
Perihelion (tp_cal, UTC) 2023-06-10T10:47:21.906240Z
Orbit solution date (soln_date, UTC) 2025-10-03T14:42:16Z
Obs used 558
NEO -
M1 6.800
K1 9.250
PC -
Discovery observation (MPC, UTC) 2021-08-26T07:09:57.139200Z
Discovery magnitude (MPC) 20.07 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 値
Epoch (epoch_cal, TDB) 2023-04-14.0000000
e 1.00316029
q (au) 7.564703
a (au) -2393.669779
i (deg) 71.474447
Ω (om, deg) 183.332460
ω (w, deg) 146.998903
M (ma, deg) -0.000483

等級

C/2021 Q4 (Fuls) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (0.678 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目 値
H0 0.678
n 6.000
gf 1.000
gb -0.500
k 1.000
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 01:49:44.87 -22:50:40.8 HIP 8554 9.61
2026-09-20 12:00 01:49:37.76 -22:53:05.6 HIP 8554 12.28
2026-09-21 00:00 01:49:30.59 -22:55:29.8 HIP 8554 15.05
2026-09-21 12:00 01:49:23.36 -22:57:53.5 HIP 8554 17.86
2026-09-22 00:00 01:49:16.07 -23:00:16.6 HIP 8554 20.71
2026-09-22 12:00 01:49:08.73 -23:02:39.2 HIP 8554 23.58
2026-09-23 00:00 01:49:01.33 -23:05:01.2 HIP 8340 25.54
2026-09-23 12:00 01:48:53.87 -23:07:22.7 HIP 8340 25.79
2026-09-24 00:00 01:48:46.35 -23:09:43.6 HIP 8340 26.35
2026-09-24 12:00 01:48:38.79 -23:12:03.9 HIP 8340 27.19
2026-09-25 00:00 01:48:31.17 -23:14:23.5 HIP 8340 28.30
2026-09-25 12:00 01:48:23.49 -23:16:42.6 HIP 8340 29.64
2026-09-26 00:00 01:48:15.77 -23:19:01.1 HIP 8340 31.18
2026-09-26 12:00 01:48:07.99 -23:21:18.9 HIP 8434 31.90
2026-09-27 00:00 01:48:00.17 -23:23:36.1 HIP 8434 30.22
2026-09-27 12:00 01:47:52.29 -23:25:52.6 HIP 8434 28.76
2026-09-28 00:00 01:47:44.37 -23:28:08.5 HIP 8434 27.54
2026-09-28 12:00 01:47:36.40 -23:30:23.7 HIP 8434 26.59
2026-09-29 00:00 01:47:28.38 -23:32:38.3 HIP 8434 25.96
2026-09-29 12:00 01:47:20.32 -23:34:52.1 HIP 8434 25.65
2026-09-30 00:00 01:47:12.21 -23:37:05.3 HIP 8281 24.78
2026-09-30 12:00 01:47:04.07 -23:39:17.7 HIP 8281 22.16
2026-10-01 00:00 01:46:55.87 -23:41:29.5 HIP 8281 19.64
2026-10-01 12:00 01:46:47.64 -23:43:40.5 HIP 8281 17.23
2026-10-02 00:00 01:46:39.37 -23:45:50.7 HIP 8281 15.02
2026-10-02 12:00 01:46:31.05 -23:48:00.3 HIP 8281 13.07
2026-10-03 00:00 01:46:22.70 -23:50:09.0 HIP 8281 11.54
2026-10-03 12:00 01:46:14.31 -23:52:17.1 HIP 8281 10.59
2026-10-04 00:00 01:46:05.88 -23:54:24.3 HIP 8281 10.39
2026-10-04 12:00 01:45:57.42 -23:56:30.8 HIP 8281 10.97
2026-10-05 00:00 01:45:48.93 -23:58:36.4 HIP 8281 12.23
2026-10-05 12:00 01:45:40.40 -24:00:41.3 HIP 8281 13.97
2026-10-06 00:00 01:45:31.83 -24:02:45.4 HIP 8281 16.03
2026-10-06 12:00 01:45:23.24 -24:04:48.6 HIP 8281 18.31
2026-10-07 00:00 01:45:14.62 -24:06:51.0 HIP 8107 18.09
2026-10-07 12:00 01:45:05.96 -24:08:52.6 HIP 8107 15.29
2026-10-08 00:00 01:44:57.28 -24:10:53.3 HIP 8107 12.51
2026-10-08 12:00 01:44:48.57 -24:12:53.2 HIP 8107 9.76
2026-10-09 00:00 01:44:39.84 -24:14:52.2 HIP 8107 7.06
2026-10-09 12:00 01:44:31.08 -24:16:50.3 HIP 8107 4.49
2026-10-10 00:00 01:44:22.30 -24:18:47.6 HIP 8107 2.49
2026-10-10 12:00 01:44:13.50 -24:20:43.9 HIP 8107 2.79
2026-10-11 00:00 01:44:04.68 -24:22:39.4 HIP 8107 4.98