メタデータ
| 項目 |
値 |
| Designation |
P/2018 L4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-07-31T20:14:06.267840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:44Z |
| Obs used |
129 |
| NEO |
- |
| M1 |
15.000 |
| K1 |
21.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-06-08T12:14:11.040000Z |
| Discovery magnitude (MPC) |
21.00 i |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-06-29.0000000 |
| e |
0.66033053 |
| q (au) |
1.676234 |
| a (au) |
4.934898 |
| i (deg) |
26.625477 |
| Ω (om, deg) |
145.193041 |
| ω (w, deg) |
140.432575 |
| M (ma, deg) |
357.047219 |
等級
散乱 + 全体線形
$$
M_a = (17.644 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
17.644 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.692 |
| k |
0.800 |
| 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) |
| 2026-05-12 00:00 |
08:10:56.34 |
+12:35:10.1 |
HIP 39978 |
17.03 |
| 2026-05-12 12:00 |
08:11:05.09 |
+12:35:34.9 |
HIP 39978 |
18.90 |
| 2026-05-13 00:00 |
08:11:13.95 |
+12:35:59.1 |
HIP 39978 |
20.86 |
| 2026-05-13 12:00 |
08:11:22.91 |
+12:36:22.7 |
HIP 39978 |
22.89 |
| 2026-05-14 00:00 |
08:11:31.99 |
+12:36:45.8 |
HIP 39978 |
24.99 |
| 2026-05-14 12:00 |
08:11:41.18 |
+12:37:08.4 |
HIP 39978 |
27.13 |
| 2026-05-15 00:00 |
08:11:50.47 |
+12:37:30.4 |
HIP 39978 |
29.32 |
| 2026-05-15 12:00 |
08:11:59.88 |
+12:37:51.8 |
HIP 39978 |
31.56 |
| 2026-05-16 00:00 |
08:12:09.39 |
+12:38:12.7 |
HIP 39978 |
33.83 |
| 2026-05-16 12:00 |
08:12:19.00 |
+12:38:33.0 |
HIP 40331 |
34.28 |
| 2026-05-17 00:00 |
08:12:28.72 |
+12:38:52.8 |
HIP 40331 |
32.75 |
| 2026-05-17 12:00 |
08:12:38.55 |
+12:39:12.0 |
HIP 40331 |
31.30 |
| 2026-05-18 00:00 |
08:12:48.48 |
+12:39:30.7 |
HIP 40331 |
29.96 |
| 2026-05-18 12:00 |
08:12:58.52 |
+12:39:48.8 |
HIP 40331 |
28.74 |
| 2026-05-19 00:00 |
08:13:08.66 |
+12:40:06.4 |
HIP 40331 |
27.66 |
| 2026-05-19 12:00 |
08:13:18.90 |
+12:40:23.4 |
HIP 40331 |
26.76 |
| 2026-05-20 00:00 |
08:13:29.24 |
+12:40:39.8 |
HIP 40354 |
25.57 |
| 2026-05-20 12:00 |
08:13:39.68 |
+12:40:55.7 |
HIP 40354 |
24.17 |
| 2026-05-21 00:00 |
08:13:50.22 |
+12:41:11.1 |
HIP 40354 |
22.98 |
| 2026-05-21 12:00 |
08:14:00.87 |
+12:41:25.9 |
HIP 40375 |
21.70 |
| 2026-05-22 00:00 |
08:14:11.61 |
+12:41:40.1 |
HIP 40375 |
20.58 |
| 2026-05-22 12:00 |
08:14:22.44 |
+12:41:53.9 |
HIP 40375 |
19.74 |
| 2026-05-23 00:00 |
08:14:33.38 |
+12:42:07.0 |
HIP 40375 |
19.25 |
| 2026-05-23 12:00 |
08:14:44.41 |
+12:42:19.7 |
HIP 40375 |
19.13 |
| 2026-05-24 00:00 |
08:14:55.53 |
+12:42:31.8 |
HIP 40375 |
19.41 |
| 2026-05-24 12:00 |
08:15:06.75 |
+12:42:43.3 |
HIP 40375 |
20.07 |
| 2026-05-25 00:00 |
08:15:18.07 |
+12:42:54.3 |
HIP 40375 |
21.09 |
| 2026-05-25 12:00 |
08:15:29.47 |
+12:43:04.8 |
HIP 40375 |
22.42 |
| 2026-05-26 00:00 |
08:15:40.97 |
+12:43:14.7 |
HIP 40375 |
24.03 |
| 2026-05-26 12:00 |
08:15:52.56 |
+12:43:24.1 |
HIP 40375 |
25.87 |
| 2026-05-27 00:00 |
08:16:04.25 |
+12:43:33.0 |
HIP 40375 |
27.89 |
| 2026-05-27 12:00 |
08:16:16.02 |
+12:43:41.3 |
HIP 40375 |
30.07 |
| 2026-05-28 00:00 |
08:16:27.88 |
+12:43:49.1 |
HIP 40686 |
29.56 |
| 2026-05-28 12:00 |
08:16:39.83 |
+12:43:56.4 |
HIP 40686 |
26.88 |
| 2026-05-29 00:00 |
08:16:51.87 |
+12:44:03.1 |
HIP 40686 |
24.24 |
| 2026-05-29 12:00 |
08:17:04.00 |
+12:44:09.3 |
HIP 40686 |
21.65 |
| 2026-05-30 00:00 |
08:17:16.21 |
+12:44:15.0 |
HIP 40686 |
19.14 |
| 2026-05-30 12:00 |
08:17:28.51 |
+12:44:20.2 |
HIP 40686 |
16.77 |
| 2026-05-31 00:00 |
08:17:40.90 |
+12:44:24.8 |
HIP 40686 |
14.62 |
| 2026-05-31 12:00 |
08:17:53.37 |
+12:44:28.9 |
HIP 40686 |
12.80 |
| 2026-06-01 00:00 |
08:18:05.92 |
+12:44:32.5 |
HIP 40686 |
11.49 |
| 2026-06-01 12:00 |
08:18:18.56 |
+12:44:35.5 |
HIP 40686 |
10.90 |
| 2026-06-02 00:00 |
08:18:31.28 |
+12:44:38.1 |
HIP 40686 |
11.16 |