C/2021 Q4 (Fuls)

メタデータ

項目
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
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
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)
2026-07-29 00:00 01:54:35.40 -18:23:00.9 HIP 8864 19.62
2026-07-29 12:00 01:54:37.50 -18:25:20.5 HIP 8864 21.96
2026-07-30 00:00 01:54:39.51 -18:27:40.6 HIP 8864 24.30
2026-07-30 12:00 01:54:41.43 -18:30:01.2 HIP 9025 23.19
2026-07-31 00:00 01:54:43.25 -18:32:22.3 HIP 9025 22.16
2026-07-31 12:00 01:54:44.97 -18:34:44.0 HIP 9025 21.38
2026-08-01 00:00 01:54:46.61 -18:37:06.1 HIP 9025 20.86
2026-08-01 12:00 01:54:48.15 -18:39:28.7 HIP 9025 20.64
2026-08-02 00:00 01:54:49.59 -18:41:51.7 HIP 9025 20.72
2026-08-02 12:00 01:54:50.94 -18:44:15.3 HIP 9025 21.10
2026-08-03 00:00 01:54:52.20 -18:46:39.3 HIP 9025 21.76
2026-08-03 12:00 01:54:53.35 -18:49:03.7 HIP 9025 22.69
2026-08-04 00:00 01:54:54.42 -18:51:28.7 HIP 9025 23.85
2026-08-04 12:00 01:54:55.39 -18:53:54.0 HIP 8956 23.33
2026-08-05 00:00 01:54:56.26 -18:56:19.8 HIP 8956 20.93
2026-08-05 12:00 01:54:57.04 -18:58:46.1 HIP 8956 18.54
2026-08-06 00:00 01:54:57.72 -19:01:12.7 HIP 8956 16.16
2026-08-06 12:00 01:54:58.31 -19:03:39.8 HIP 8956 13.81
2026-08-07 00:00 01:54:58.80 -19:06:07.3 HIP 8956 11.51
2026-08-07 12:00 01:54:59.19 -19:08:35.2 HIP 8956 9.29
2026-08-08 00:00 01:54:59.49 -19:11:03.5 HIP 8956 7.25
2026-08-08 12:00 01:54:59.69 -19:13:32.2 HIP 8956 5.58
2026-08-09 00:00 01:54:59.80 -19:16:01.2 HIP 8956 4.72
2026-08-09 12:00 01:54:59.80 -19:18:30.7 HIP 8956 5.10
2026-08-10 00:00 01:54:59.72 -19:21:00.5 HIP 8956 6.51
2026-08-10 12:00 01:54:59.53 -19:23:30.6 HIP 8956 8.46
2026-08-11 00:00 01:54:59.25 -19:26:01.1 HIP 8956 10.65
2026-08-11 12:00 01:54:58.87 -19:28:31.9 HIP 8956 12.98
2026-08-12 00:00 01:54:58.40 -19:31:03.1 HIP 8956 15.38
2026-08-12 12:00 01:54:57.83 -19:33:34.5 HIP 8956 17.82
2026-08-13 00:00 01:54:57.16 -19:36:06.3 HIP 8956 20.29
2026-08-13 12:00 01:54:56.40 -19:38:38.4 HIP 8956 22.79
2026-08-14 00:00 01:54:55.54 -19:41:10.7 HIP 8956 25.31
2026-08-14 12:00 01:54:54.59 -19:43:43.4 HIP 8956 27.84
2026-08-15 00:00 01:54:53.54 -19:46:16.3 HIP 8956 30.39
2026-08-15 12:00 01:54:52.39 -19:48:49.4 HIP 8956 32.94
2026-08-16 00:00 01:54:51.15 -19:51:22.9 HIP 8770 35.30
2026-08-16 12:00 01:54:49.81 -19:53:56.5 HIP 8770 36.64
2026-08-17 00:00 01:54:48.38 -19:56:30.4 HIP 8770 38.09
2026-08-17 12:00 01:54:46.85 -19:59:04.5 HIP 8988 37.64
2026-08-18 00:00 01:54:45.23 -20:01:38.8 HIP 8988 35.44
2026-08-18 12:00 01:54:43.51 -20:04:13.4 HIP 8988 33.31
2026-08-19 00:00 01:54:41.70 -20:06:48.1 HIP 8988 31.25