メタデータ
| 項目 |
値 |
| 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 |
値 |
| 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
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 |
値 |
| 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) |
| 2026-09-20 00:00 |
19:25:45.81 |
-16:23:47.6 |
HIP 95670 |
26.42 |
| 2026-09-20 12:00 |
19:25:43.70 |
-16:24:01.1 |
HIP 95482 |
26.83 |
| 2026-09-21 00:00 |
19:25:41.67 |
-16:24:14.4 |
HIP 95482 |
26.51 |
| 2026-09-21 12:00 |
19:25:39.73 |
-16:24:27.6 |
HIP 95482 |
26.20 |
| 2026-09-22 00:00 |
19:25:37.87 |
-16:24:40.7 |
HIP 95482 |
25.91 |
| 2026-09-22 12:00 |
19:25:36.10 |
-16:24:53.6 |
HIP 95482 |
25.62 |
| 2026-09-23 00:00 |
19:25:34.41 |
-16:25:06.3 |
HIP 95482 |
25.35 |
| 2026-09-23 12:00 |
19:25:32.81 |
-16:25:18.9 |
HIP 95482 |
25.09 |
| 2026-09-24 00:00 |
19:25:31.28 |
-16:25:31.4 |
HIP 95482 |
24.84 |
| 2026-09-24 12:00 |
19:25:29.85 |
-16:25:43.7 |
HIP 95482 |
24.60 |
| 2026-09-25 00:00 |
19:25:28.49 |
-16:25:55.9 |
HIP 95482 |
24.36 |
| 2026-09-25 12:00 |
19:25:27.23 |
-16:26:07.9 |
HIP 95482 |
24.14 |
| 2026-09-26 00:00 |
19:25:26.04 |
-16:26:19.7 |
HIP 95482 |
23.92 |
| 2026-09-26 12:00 |
19:25:24.94 |
-16:26:31.4 |
HIP 95482 |
23.71 |
| 2026-09-27 00:00 |
19:25:23.93 |
-16:26:42.9 |
HIP 95482 |
23.50 |
| 2026-09-27 12:00 |
19:25:23.00 |
-16:26:54.3 |
HIP 95482 |
23.30 |
| 2026-09-28 00:00 |
19:25:22.15 |
-16:27:05.6 |
HIP 95482 |
23.11 |
| 2026-09-28 12:00 |
19:25:21.39 |
-16:27:16.6 |
HIP 95482 |
22.92 |
| 2026-09-29 00:00 |
19:25:20.72 |
-16:27:27.5 |
HIP 95482 |
22.73 |
| 2026-09-29 12:00 |
19:25:20.12 |
-16:27:38.3 |
HIP 95482 |
22.55 |
| 2026-09-30 00:00 |
19:25:19.62 |
-16:27:48.9 |
HIP 95482 |
22.37 |
| 2026-09-30 12:00 |
19:25:19.20 |
-16:27:59.3 |
HIP 95482 |
22.20 |
| 2026-10-01 00:00 |
19:25:18.86 |
-16:28:09.6 |
HIP 95482 |
22.03 |
| 2026-10-01 12:00 |
19:25:18.61 |
-16:28:19.7 |
HIP 95482 |
21.86 |
| 2026-10-02 00:00 |
19:25:18.44 |
-16:28:29.6 |
HIP 95482 |
21.69 |
| 2026-10-02 12:00 |
19:25:18.36 |
-16:28:39.4 |
HIP 95482 |
21.53 |
| 2026-10-03 00:00 |
19:25:18.36 |
-16:28:49.0 |
HIP 95482 |
21.37 |
| 2026-10-03 12:00 |
19:25:18.45 |
-16:28:58.4 |
HIP 95482 |
21.21 |
| 2026-10-04 00:00 |
19:25:18.63 |
-16:29:07.7 |
HIP 95482 |
21.06 |
| 2026-10-04 12:00 |
19:25:18.89 |
-16:29:16.8 |
HIP 95482 |
20.91 |
| 2026-10-05 00:00 |
19:25:19.23 |
-16:29:25.7 |
HIP 95482 |
20.76 |
| 2026-10-05 12:00 |
19:25:19.66 |
-16:29:34.4 |
HIP 95482 |
20.61 |
| 2026-10-06 00:00 |
19:25:20.18 |
-16:29:43.0 |
HIP 95482 |
20.47 |
| 2026-10-06 12:00 |
19:25:20.78 |
-16:29:51.4 |
HIP 95482 |
20.33 |
| 2026-10-07 00:00 |
19:25:21.47 |
-16:29:59.6 |
HIP 95482 |
20.20 |
| 2026-10-07 12:00 |
19:25:22.24 |
-16:30:07.6 |
HIP 95482 |
20.07 |
| 2026-10-08 00:00 |
19:25:23.10 |
-16:30:15.5 |
HIP 95482 |
19.95 |
| 2026-10-08 12:00 |
19:25:24.04 |
-16:30:23.2 |
HIP 95482 |
19.84 |
| 2026-10-09 00:00 |
19:25:25.07 |
-16:30:30.7 |
HIP 95482 |
19.73 |
| 2026-10-09 12:00 |
19:25:26.18 |
-16:30:38.0 |
HIP 95482 |
19.63 |
| 2026-10-10 00:00 |
19:25:27.38 |
-16:30:45.1 |
HIP 95482 |
19.54 |
| 2026-10-10 12:00 |
19:25:28.66 |
-16:30:52.0 |
HIP 95482 |
19.46 |
| 2026-10-11 00:00 |
19:25:30.03 |
-16:30:58.8 |
HIP 95482 |
19.39 |