メタデータ

項目	値
Designation	465P/Hill
Type	P
Perihelion (tp_cal, UTC)	2008-08-18T17:57:24.065280Z
Orbit solution date (soln_date, UTC)	2024-07-13T19:12:23Z
Obs used	706
NEO	-
M1	6.900
K1	25.250
PC	0.030

オスキュレーティング軌道要素

項目	値
Epoch (epoch_cal, TDB)	2011-07-24.0000000
e	0.61380782
q (au)	2.322142
a (au)	6.012919
i (deg)	25.854343
Ω (om, deg)	217.938849
ω (w, deg)	141.510289
M (ma, deg)	71.475305

等級

散乱 + 全体線形

$$ M_a = (10.276 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目	値
H0	10.276
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

残差 (区間線形)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

開始日 (UTC)	終了日 (UTC)	a	b
2023-06-08	2024-01-05	+9.7551	-4.150

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)
2026-05-12 00:00	08:28:40.31	-06:46:40.4	HIP 41495	29.77
2026-05-12 12:00	08:28:49.39	-06:45:30.1	HIP 41717	29.02
2026-05-13 00:00	08:28:58.58	-06:44:20.6	HIP 41664	27.35
2026-05-13 12:00	08:29:07.87	-06:43:12.0	HIP 41664	25.46
2026-05-14 00:00	08:29:17.27	-06:42:04.2	HIP 41664	23.70
2026-05-14 12:00	08:29:26.77	-06:40:57.3	HIP 41664	22.12
2026-05-15 00:00	08:29:36.37	-06:39:51.2	HIP 41664	20.77
2026-05-15 12:00	08:29:46.08	-06:38:46.1	HIP 41664	19.69
2026-05-16 00:00	08:29:55.89	-06:37:41.8	HIP 41664	18.93
2026-05-16 12:00	08:30:05.81	-06:36:38.3	HIP 41664	18.56
2026-05-17 00:00	08:30:15.82	-06:35:35.8	HIP 41664	18.59
2026-05-17 12:00	08:30:25.94	-06:34:34.1	HIP 41664	19.04
2026-05-18 00:00	08:30:36.15	-06:33:33.3	HIP 41664	19.88
2026-05-18 12:00	08:30:46.47	-06:32:33.3	HIP 41834	19.15
2026-05-19 00:00	08:30:56.88	-06:31:34.3	HIP 41834	16.65
2026-05-19 12:00	08:31:07.38	-06:30:36.1	HIP 41834	14.25
2026-05-20 00:00	08:31:17.99	-06:29:38.8	HIP 41834	12.02
2026-05-20 12:00	08:31:28.69	-06:28:42.4	HIP 41834	10.09
2026-05-21 00:00	08:31:39.48	-06:27:46.9	HIP 41834	8.67
2026-05-21 12:00	08:31:50.37	-06:26:52.3	HIP 41834	8.06
2026-05-22 00:00	08:32:01.35	-06:25:58.5	HIP 41834	8.45
2026-05-22 12:00	08:32:12.43	-06:25:05.7	HIP 41834	9.75
2026-05-23 00:00	08:32:23.59	-06:24:13.7	HIP 41834	11.66
2026-05-23 12:00	08:32:34.85	-06:23:22.7	HIP 41834	13.94
2026-05-24 00:00	08:32:46.19	-06:22:32.5	HIP 41834	16.45
2026-05-24 12:00	08:32:57.63	-06:21:43.2	HIP 42025	17.15
2026-05-25 00:00	08:33:09.15	-06:20:54.7	HIP 42025	15.02
2026-05-25 12:00	08:33:20.76	-06:20:07.2	HIP 42025	13.19
2026-05-26 00:00	08:33:32.45	-06:19:20.6	HIP 42025	11.81
2026-05-26 12:00	08:33:44.24	-06:18:34.8	HIP 42025	11.08
2026-05-27 00:00	08:33:56.10	-06:17:50.0	HIP 42025	11.14
2026-05-27 12:00	08:34:08.06	-06:17:06.0	HIP 42025	11.98
2026-05-28 00:00	08:34:20.09	-06:16:22.9	HIP 42025	13.47
2026-05-28 12:00	08:34:32.21	-06:15:40.7	HIP 42025	15.43
2026-05-29 00:00	08:34:44.41	-06:14:59.4	HIP 42025	17.73
2026-05-29 12:00	08:34:56.69	-06:14:18.9	HIP 42018	19.89
2026-05-30 00:00	08:35:09.05	-06:13:39.4	HIP 42018	21.98
2026-05-30 12:00	08:35:21.49	-06:13:00.7	HIP 42018	24.33
2026-05-31 00:00	08:35:34.02	-06:12:22.9	HIP 42018	26.87
2026-05-31 12:00	08:35:46.62	-06:11:46.0	HIP 42292	28.74
2026-06-01 00:00	08:35:59.30	-06:11:10.0	HIP 42292	26.62
2026-06-01 12:00	08:36:12.05	-06:10:34.9	HIP 42292	24.70
2026-06-02 00:00	08:36:24.88	-06:10:00.7	HIP 42292	23.06