メタデータ
| 項目 |
値 |
| Designation |
P/2018 P4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-11-07T08:17:57.094080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:46Z |
| Obs used |
116 |
| NEO |
- |
| M1 |
11.600 |
| K1 |
10.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-08-08T12:01:59.232000Z |
| Discovery magnitude (MPC) |
20.60 w |
| 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) |
2018-09-13.0000000 |
| e |
0.44931114 |
| q (au) |
3.666142 |
| a (au) |
6.657375 |
| i (deg) |
23.112765 |
| Ω (om, deg) |
353.110347 |
| ω (w, deg) |
8.115551 |
| M (ma, deg) |
356.824339 |
等級
散乱 + 全体線形
$$
M_a = (8.263 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.263 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.852 |
| k |
0.999 |
| 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 |
11:09:43.79 |
+06:09:12.5 |
HIP 54563 |
23.45 |
| 2026-05-12 12:00 |
11:09:40.80 |
+06:09:09.0 |
HIP 54563 |
23.48 |
| 2026-05-13 00:00 |
11:09:37.91 |
+06:09:05.0 |
HIP 54563 |
23.53 |
| 2026-05-13 12:00 |
11:09:35.12 |
+06:09:00.3 |
HIP 54563 |
23.58 |
| 2026-05-14 00:00 |
11:09:32.42 |
+06:08:55.1 |
HIP 54563 |
23.63 |
| 2026-05-14 12:00 |
11:09:29.82 |
+06:08:49.3 |
HIP 54563 |
23.69 |
| 2026-05-15 00:00 |
11:09:27.32 |
+06:08:42.9 |
HIP 54563 |
23.75 |
| 2026-05-15 12:00 |
11:09:24.92 |
+06:08:36.0 |
HIP 54563 |
23.81 |
| 2026-05-16 00:00 |
11:09:22.61 |
+06:08:28.4 |
HIP 54563 |
23.87 |
| 2026-05-16 12:00 |
11:09:20.40 |
+06:08:20.2 |
HIP 54563 |
23.93 |
| 2026-05-17 00:00 |
11:09:18.29 |
+06:08:11.5 |
HIP 54563 |
23.98 |
| 2026-05-17 12:00 |
11:09:16.28 |
+06:08:02.2 |
HIP 54563 |
24.02 |
| 2026-05-18 00:00 |
11:09:14.37 |
+06:07:52.3 |
HIP 54563 |
24.06 |
| 2026-05-18 12:00 |
11:09:12.56 |
+06:07:41.8 |
HIP 54563 |
24.09 |
| 2026-05-19 00:00 |
11:09:10.84 |
+06:07:30.7 |
HIP 54563 |
24.11 |
| 2026-05-19 12:00 |
11:09:09.22 |
+06:07:19.1 |
HIP 54563 |
24.12 |
| 2026-05-20 00:00 |
11:09:07.70 |
+06:07:06.8 |
HIP 54563 |
24.11 |
| 2026-05-20 12:00 |
11:09:06.28 |
+06:06:54.0 |
HIP 54563 |
24.09 |
| 2026-05-21 00:00 |
11:09:04.96 |
+06:06:40.6 |
HIP 54563 |
24.06 |
| 2026-05-21 12:00 |
11:09:03.73 |
+06:06:26.6 |
HIP 54563 |
24.02 |
| 2026-05-22 00:00 |
11:09:02.60 |
+06:06:12.0 |
HIP 54563 |
23.96 |
| 2026-05-22 12:00 |
11:09:01.58 |
+06:05:56.8 |
HIP 54563 |
23.88 |
| 2026-05-23 00:00 |
11:09:00.64 |
+06:05:41.1 |
HIP 54563 |
23.79 |
| 2026-05-23 12:00 |
11:08:59.81 |
+06:05:24.7 |
HIP 54563 |
23.68 |
| 2026-05-24 00:00 |
11:08:59.07 |
+06:05:07.8 |
HIP 54563 |
23.55 |
| 2026-05-24 12:00 |
11:08:58.43 |
+06:04:50.4 |
HIP 54563 |
23.41 |
| 2026-05-25 00:00 |
11:08:57.89 |
+06:04:32.3 |
HIP 54563 |
23.25 |
| 2026-05-25 12:00 |
11:08:57.45 |
+06:04:13.7 |
HIP 54563 |
23.07 |
| 2026-05-26 00:00 |
11:08:57.10 |
+06:03:54.5 |
HIP 54563 |
22.87 |
| 2026-05-26 12:00 |
11:08:56.85 |
+06:03:34.7 |
HIP 54563 |
22.65 |
| 2026-05-27 00:00 |
11:08:56.69 |
+06:03:14.4 |
HIP 54563 |
22.41 |
| 2026-05-27 12:00 |
11:08:56.63 |
+06:02:53.5 |
HIP 54563 |
22.15 |
| 2026-05-28 00:00 |
11:08:56.67 |
+06:02:32.0 |
HIP 54563 |
21.87 |
| 2026-05-28 12:00 |
11:08:56.80 |
+06:02:10.0 |
HIP 54563 |
21.57 |
| 2026-05-29 00:00 |
11:08:57.03 |
+06:01:47.4 |
HIP 54563 |
21.25 |
| 2026-05-29 12:00 |
11:08:57.36 |
+06:01:24.2 |
HIP 54563 |
20.90 |
| 2026-05-30 00:00 |
11:08:57.78 |
+06:01:00.5 |
HIP 54563 |
20.54 |
| 2026-05-30 12:00 |
11:08:58.29 |
+06:00:36.2 |
HIP 54563 |
20.16 |
| 2026-05-31 00:00 |
11:08:58.90 |
+06:00:11.3 |
HIP 54563 |
19.75 |
| 2026-05-31 12:00 |
11:08:59.61 |
+05:59:45.9 |
HIP 54563 |
19.33 |
| 2026-06-01 00:00 |
11:09:00.41 |
+05:59:19.9 |
HIP 54563 |
18.88 |
| 2026-06-01 12:00 |
11:09:01.30 |
+05:58:53.4 |
HIP 54563 |
18.41 |
| 2026-06-02 00:00 |
11:09:02.29 |
+05:58:26.3 |
HIP 54563 |
17.91 |