P/2017 D4 (PANSTARRS)

メタデータ

項目
Designation P/2017 D4 (PANSTARRS)
Type P
Perihelion (tp_cal, UTC) 2016-09-06T15:17:49.675200Z
Orbit solution date (soln_date, UTC) 2022-07-31T01:43:23Z
Obs used 91
NEO -
M1 16.300
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2017-03-06.0000000
e 0.62891585
q (au) 2.754615
a (au) 7.423156
i (deg) 10.339594
Ω (om, deg) 266.104140
ω (w, deg) 209.796281
M (ma, deg) 8.789572

等級

P/2017 D4 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (15.387 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 15.387
n 2.000
gf 0.999
gb -1.000
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)
2026-06-01 00:00 19:51:18.11 -15:29:34.2 HIP 97620 12.94
2026-06-01 12:00 19:51:12.68 -15:29:34.3 HIP 97620 11.71
2026-06-02 00:00 19:51:07.18 -15:29:34.6 HIP 97620 10.49
2026-06-02 12:00 19:51:01.61 -15:29:35.2 HIP 97620 9.28
2026-06-03 00:00 19:50:55.97 -15:29:36.0 HIP 97620 8.10
2026-06-03 12:00 19:50:50.27 -15:29:37.1 HIP 97620 6.98
2026-06-04 00:00 19:50:44.51 -15:29:38.5 HIP 97620 5.95
2026-06-04 12:00 19:50:38.67 -15:29:40.0 HIP 97620 5.10
2026-06-05 00:00 19:50:32.78 -15:29:41.8 HIP 97620 4.52
2026-06-05 12:00 19:50:26.82 -15:29:43.9 HIP 97620 4.36
2026-06-06 00:00 19:50:20.79 -15:29:46.2 HIP 97620 4.67
2026-06-06 12:00 19:50:14.71 -15:29:48.7 HIP 97620 5.38
2026-06-07 00:00 19:50:08.56 -15:29:51.5 HIP 97620 6.37
2026-06-07 12:00 19:50:02.35 -15:29:54.5 HIP 97620 7.53
2026-06-08 00:00 19:49:56.08 -15:29:57.7 HIP 97620 8.81
2026-06-08 12:00 19:49:49.74 -15:30:01.2 HIP 97620 10.17
2026-06-09 00:00 19:49:43.35 -15:30:04.9 HIP 97620 11.59
2026-06-09 12:00 19:49:36.90 -15:30:08.9 HIP 97620 13.05
2026-06-10 00:00 19:49:30.38 -15:30:13.1 HIP 97620 14.55
2026-06-10 12:00 19:49:23.81 -15:30:17.5 HIP 97620 16.07
2026-06-11 00:00 19:49:17.18 -15:30:22.1 HIP 97620 17.62
2026-06-11 12:00 19:49:10.49 -15:30:27.0 HIP 97620 19.19
2026-06-12 00:00 19:49:03.75 -15:30:32.2 HIP 97620 20.78
2026-06-12 12:00 19:48:56.95 -15:30:37.5 HIP 97620 22.39
2026-06-13 00:00 19:48:50.09 -15:30:43.1 HIP 97620 24.02
2026-06-13 12:00 19:48:43.18 -15:30:48.9 HIP 97620 25.67
2026-06-14 00:00 19:48:36.22 -15:30:54.9 HIP 97620 27.33
2026-06-14 12:00 19:48:29.20 -15:31:01.2 HIP 97620 29.01
2026-06-15 00:00 19:48:22.13 -15:31:07.7 HIP 97620 30.70
2026-06-15 12:00 19:48:15.00 -15:31:14.4 HIP 97273 32.34
2026-06-16 00:00 19:48:07.83 -15:31:21.3 HIP 97273 30.76
2026-06-16 12:00 19:48:00.60 -15:31:28.4 HIP 97273 29.20
2026-06-17 00:00 19:47:53.33 -15:31:35.8 HIP 97273 27.65
2026-06-17 12:00 19:47:46.00 -15:31:43.4 HIP 97273 26.11
2026-06-18 00:00 19:47:38.63 -15:31:51.2 HIP 97273 24.60
2026-06-18 12:00 19:47:31.21 -15:31:59.2 HIP 97273 23.12
2026-06-19 00:00 19:47:23.75 -15:32:07.4 HIP 97273 21.67
2026-06-19 12:00 19:47:16.23 -15:32:15.9 HIP 97273 20.28
2026-06-20 00:00 19:47:08.68 -15:32:24.5 HIP 97273 18.96
2026-06-20 12:00 19:47:01.07 -15:32:33.4 HIP 97273 17.72
2026-06-21 00:00 19:46:53.43 -15:32:42.4 HIP 97273 16.59
2026-06-21 12:00 19:46:45.74 -15:32:51.7 HIP 97273 15.59
2026-06-22 00:00 19:46:38.01 -15:33:01.1 HIP 97273 14.75