P/2025 W4 (PANSTARRS)
メタデータ
| 項目 |
値 |
| Designation |
P/2025 W4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-10-04T11:21:25.992000Z |
| Orbit solution date (soln_date, UTC) |
2026-01-13T08:12:19Z |
| Obs used |
99 |
| NEO |
- |
| M1 |
17.300 |
| K1 |
10.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2025-11-30.0000000 |
| e |
0.21117810 |
| q (au) |
2.034368 |
| a (au) |
2.578995 |
| i (deg) |
1.298191 |
| Ω (om, deg) |
237.120965 |
| ω (w, deg) |
172.278336 |
| M (ma, deg) |
13.451868 |
等級
散乱 + 全体線形
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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
ファインディングチャート
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
04:28:00.68 |
+20:40:24.8 |
HIP 20897 |
9.71 |
| 2026-02-03 12:00 |
04:28:23.19 |
+20:41:12.4 |
HIP 20897 |
4.47 |
| 2026-02-04 00:00 |
04:28:46.12 |
+20:42:00.8 |
HIP 20897 |
1.65 |
| 2026-02-04 12:00 |
04:29:09.45 |
+20:42:49.9 |
HIP 20897 |
6.74 |
| 2026-02-05 00:00 |
04:29:33.20 |
+20:43:39.8 |
HIP 20994 |
12.08 |
| 2026-02-05 12:00 |
04:29:57.34 |
+20:44:30.5 |
HIP 20994 |
8.46 |
| 2026-02-06 00:00 |
04:30:21.89 |
+20:45:21.9 |
HIP 20994 |
7.93 |
| 2026-02-06 12:00 |
04:30:46.84 |
+20:46:14.0 |
HIP 20994 |
11.08 |
| 2026-02-07 00:00 |
04:31:12.18 |
+20:47:06.8 |
HIP 20994 |
15.97 |
| 2026-02-07 12:00 |
04:31:37.91 |
+20:48:00.2 |
HIP 20994 |
21.51 |
| 2026-02-08 00:00 |
04:32:04.03 |
+20:48:54.3 |
HIP 20994 |
27.36 |
| 2026-02-08 12:00 |
04:32:30.54 |
+20:49:49.0 |
HIP 21256 |
24.73 |
| 2026-02-09 00:00 |
04:32:57.43 |
+20:50:44.3 |
HIP 21256 |
20.53 |
| 2026-02-09 12:00 |
04:33:24.70 |
+20:51:40.2 |
HIP 21256 |
17.63 |
| 2026-02-10 00:00 |
04:33:52.35 |
+20:52:36.7 |
HIP 21256 |
16.83 |
| 2026-02-10 12:00 |
04:34:20.37 |
+20:53:33.7 |
HIP 21318 |
13.26 |
| 2026-02-11 00:00 |
04:34:48.77 |
+20:54:31.2 |
HIP 21318 |
12.23 |
| 2026-02-11 12:00 |
04:35:17.53 |
+20:55:29.3 |
HIP 21318 |
14.65 |
| 2026-02-12 00:00 |
04:35:46.66 |
+20:56:27.8 |
HIP 21318 |
19.35 |
| 2026-02-12 12:00 |
04:36:16.15 |
+20:57:26.8 |
HIP 21318 |
25.14 |
| 2026-02-13 00:00 |
04:36:46.00 |
+20:58:26.3 |
HIP 21604 |
27.24 |
| 2026-02-13 12:00 |
04:37:16.20 |
+20:59:26.1 |
HIP 21604 |
23.04 |
| 2026-02-14 00:00 |
04:37:46.76 |
+21:00:26.4 |
HIP 21639 |
20.44 |
| 2026-02-14 12:00 |
04:38:17.68 |
+21:01:27.1 |
HIP 21639 |
16.68 |
| 2026-02-15 00:00 |
04:38:48.94 |
+21:02:28.1 |
HIP 21639 |
15.64 |
| 2026-02-15 12:00 |
04:39:20.54 |
+21:03:29.5 |
HIP 21639 |
17.92 |
| 2026-02-16 00:00 |
04:39:52.49 |
+21:04:31.2 |
HIP 21639 |
22.60 |
| 2026-02-16 12:00 |
04:40:24.78 |
+21:05:33.2 |
HIP 21818 |
17.05 |
| 2026-02-17 00:00 |
04:40:57.40 |
+21:06:35.5 |
HIP 21818 |
13.44 |
| 2026-02-17 12:00 |
04:41:30.36 |
+21:07:38.0 |
HIP 21818 |
13.76 |
| 2026-02-18 00:00 |
04:42:03.64 |
+21:08:40.8 |
HIP 21818 |
17.90 |
| 2026-02-18 12:00 |
04:42:37.26 |
+21:09:43.8 |
HIP 21848 |
21.34 |
| 2026-02-19 00:00 |
04:43:11.20 |
+21:10:47.0 |
HIP 21848 |
25.53 |
| 2026-02-19 12:00 |
04:43:45.46 |
+21:11:50.4 |
HIP 22042 |
28.95 |
| 2026-02-20 00:00 |
04:44:20.04 |
+21:12:54.0 |
HIP 22118 |
23.07 |
| 2026-02-20 12:00 |
04:44:54.94 |
+21:13:57.6 |
HIP 22118 |
16.72 |
| 2026-02-21 00:00 |
04:45:30.14 |
+21:15:01.5 |
HIP 22118 |
12.68 |
| 2026-02-21 12:00 |
04:46:05.66 |
+21:16:05.4 |
HIP 22118 |
13.41 |
| 2026-02-22 00:00 |
04:46:41.48 |
+21:17:09.3 |
HIP 22118 |
18.44 |
| 2026-02-22 12:00 |
04:47:17.61 |
+21:18:13.4 |
HIP 22352 |
20.10 |
| 2026-02-23 00:00 |
04:47:54.04 |
+21:19:17.5 |
HIP 22352 |
11.61 |
| 2026-02-23 12:00 |
04:48:30.76 |
+21:20:21.6 |
HIP 22352 |
3.36 |
| 2026-02-24 00:00 |
04:49:07.77 |
+21:21:25.7 |
HIP 22352 |
6.09 |