メタデータ

項目	値
Designation	292P/Li
Type	P
Perihelion (tp_cal, UTC)	2014-02-06T08:53:58.968960Z
Orbit solution date (soln_date, UTC)	2022-05-19T21:14:15Z
Obs used	498
NEO	-
M1	9.500
K1	13.500
PC	0.030

オスキュレーティング軌道要素

項目	値
Epoch (epoch_cal, TDB)	2009-05-04.0000000
e	0.58678712
q (au)	2.535007
a (au)	6.134869
i (deg)	24.316162
Ω (om, deg)	91.860435
ω (w, deg)	318.847932
M (ma, deg)	247.179418

等級

散乱 + 全体線形

$$ M_a = (8.075 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目	値
H0	8.075
n	6.000
gf	1.000
gb	-0.506
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
2013-05-09	2014-02-01	+14.5124	-5.970
2014-02-06	2018-04-23	-1.1227	+0.220

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)
2026-03-26 00:00	18:54:06.20	-24:17:37.6	HIP 92709	20.28
2026-03-26 12:00	18:54:14.41	-24:18:03.5	HIP 92709	21.56
2026-03-27 00:00	18:54:22.49	-24:18:29.7	HIP 92709	22.91
2026-03-27 12:00	18:54:30.44	-24:18:56.1	HIP 92709	24.32
2026-03-28 00:00	18:54:38.24	-24:19:22.8	HIP 92709	25.77
2026-03-28 12:00	18:54:45.91	-24:19:49.7	HIP 92780	26.83
2026-03-29 00:00	18:54:53.45	-24:20:17.0	HIP 92780	26.78
2026-03-29 12:00	18:55:00.85	-24:20:44.5	HIP 92780	26.83
2026-03-30 00:00	18:55:08.11	-24:21:12.2	HIP 92994	26.92
2026-03-30 12:00	18:55:15.23	-24:21:40.3	HIP 92994	25.35
2026-03-31 00:00	18:55:22.21	-24:22:08.6	HIP 92994	23.81
2026-03-31 12:00	18:55:29.05	-24:22:37.1	HIP 92994	22.31
2026-04-01 00:00	18:55:35.75	-24:23:06.0	HIP 92994	20.85
2026-04-01 12:00	18:55:42.32	-24:23:35.1	HIP 92994	19.44
2026-04-02 00:00	18:55:48.74	-24:24:04.6	HIP 92994	18.07
2026-04-02 12:00	18:55:55.01	-24:24:34.3	HIP 92994	16.74
2026-04-03 00:00	18:56:01.15	-24:25:04.2	HIP 92994	15.47
2026-04-03 12:00	18:56:07.14	-24:25:34.5	HIP 92994	14.25
2026-04-04 00:00	18:56:12.99	-24:26:05.1	HIP 92994	13.09
2026-04-04 12:00	18:56:18.69	-24:26:35.9	HIP 92994	12.01
2026-04-05 00:00	18:56:24.25	-24:27:07.1	HIP 92994	11.00
2026-04-05 12:00	18:56:29.66	-24:27:38.5	HIP 92994	10.08
2026-04-06 00:00	18:56:34.93	-24:28:10.2	HIP 92994	9.26
2026-04-06 12:00	18:56:40.05	-24:28:42.3	HIP 92994	8.57
2026-04-07 00:00	18:56:45.02	-24:29:14.6	HIP 92994	8.01
2026-04-07 12:00	18:56:49.84	-24:29:47.2	HIP 92994	7.61
2026-04-08 00:00	18:56:54.51	-24:30:20.2	HIP 92994	7.38
2026-04-08 12:00	18:56:59.04	-24:30:53.4	HIP 92994	7.31
2026-04-09 00:00	18:57:03.41	-24:31:26.9	HIP 92994	7.40
2026-04-09 12:00	18:57:07.63	-24:32:00.8	HIP 92994	7.64
2026-04-10 00:00	18:57:11.71	-24:32:34.9	HIP 92994	7.99
2026-04-10 12:00	18:57:15.63	-24:33:09.4	HIP 92994	8.44
2026-04-11 00:00	18:57:19.39	-24:33:44.2	HIP 92994	8.96
2026-04-11 12:00	18:57:23.00	-24:34:19.2	HIP 92994	9.52
2026-04-12 00:00	18:57:26.46	-24:34:54.6	HIP 92994	10.12
2026-04-12 12:00	18:57:29.77	-24:35:30.3	HIP 92994	10.74
2026-04-13 00:00	18:57:32.92	-24:36:06.4	HIP 92994	11.37
2026-04-13 12:00	18:57:35.91	-24:36:42.7	HIP 92994	12.01
2026-04-14 00:00	18:57:38.75	-24:37:19.4	HIP 92994	12.64
2026-04-14 12:00	18:57:41.43	-24:37:56.3	HIP 92994	13.27
2026-04-15 00:00	18:57:43.96	-24:38:33.6	HIP 92994	13.89
2026-04-15 12:00	18:57:46.32	-24:39:11.3	HIP 92994	14.49
2026-04-16 00:00	18:57:48.53	-24:39:49.2	HIP 93132	14.71