メタデータ
| 項目 |
値 |
| Designation |
31P/Schwassmann-Wachmann 2 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2010-09-29T11:16:57.953280Z |
| Orbit solution date (soln_date, UTC) |
2025-11-23T22:21:40Z |
| Obs used |
1028 |
| NEO |
- |
| M1 |
4.200 |
| K1 |
23.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2011-02-16.0000000 |
| e |
0.19303098 |
| q (au) |
3.424308 |
| a (au) |
4.243419 |
| i (deg) |
4.546365 |
| Ω (om, deg) |
114.186460 |
| ω (w, deg) |
17.932787 |
| M (ma, deg) |
15.732489 |
等級
散乱 + 全体線形
$$
M_a = (14.954 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.954 |
| n |
2.000 |
| gf |
0.961 |
| gb |
-0.501 |
| k |
1.000 |
| δ90 |
9.178 |
| 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 |
02:42:58.47 |
+11:55:28.8 |
HIP 12740 |
13.69 |
| 2026-06-01 12:00 |
02:43:29.87 |
+11:57:48.2 |
HIP 12740 |
5.99 |
| 2026-06-02 00:00 |
02:44:01.24 |
+12:00:07.1 |
HIP 12740 |
3.60 |
| 2026-06-02 12:00 |
02:44:32.59 |
+12:02:25.5 |
HIP 12740 |
10.88 |
| 2026-06-03 00:00 |
02:45:03.91 |
+12:04:43.3 |
HIP 12740 |
18.75 |
| 2026-06-03 12:00 |
02:45:35.20 |
+12:07:00.5 |
HIP 12975 |
20.85 |
| 2026-06-04 00:00 |
02:46:06.48 |
+12:09:17.2 |
HIP 12975 |
13.00 |
| 2026-06-04 12:00 |
02:46:37.72 |
+12:11:33.3 |
HIP 12975 |
5.52 |
| 2026-06-05 00:00 |
02:47:08.94 |
+12:13:48.8 |
HIP 12975 |
4.33 |
| 2026-06-05 12:00 |
02:47:40.13 |
+12:16:03.8 |
HIP 12975 |
11.55 |
| 2026-06-06 00:00 |
02:48:11.29 |
+12:18:18.2 |
HIP 12975 |
19.34 |
| 2026-06-06 12:00 |
02:48:42.42 |
+12:20:32.0 |
HIP 13201 |
25.58 |
| 2026-06-07 00:00 |
02:49:13.53 |
+12:22:45.3 |
HIP 13201 |
19.24 |
| 2026-06-07 12:00 |
02:49:44.60 |
+12:24:57.9 |
HIP 13201 |
14.54 |
| 2026-06-08 00:00 |
02:50:15.65 |
+12:27:10.0 |
HIP 13201 |
13.32 |
| 2026-06-08 12:00 |
02:50:46.66 |
+12:29:21.5 |
HIP 13201 |
16.37 |
| 2026-06-09 00:00 |
02:51:17.64 |
+12:31:32.5 |
HIP 13201 |
21.97 |
| 2026-06-09 12:00 |
02:51:48.58 |
+12:33:42.8 |
HIP 13201 |
28.64 |
| 2026-06-10 00:00 |
02:52:19.50 |
+12:35:52.5 |
HIP 13201 |
35.79 |
| 2026-06-10 12:00 |
02:52:50.37 |
+12:38:01.6 |
HIP 13557 |
31.93 |
| 2026-06-11 00:00 |
02:53:21.22 |
+12:40:10.2 |
HIP 13557 |
24.67 |
| 2026-06-11 12:00 |
02:53:52.02 |
+12:42:18.1 |
HIP 13557 |
17.91 |
| 2026-06-12 00:00 |
02:54:22.80 |
+12:44:25.4 |
HIP 13557 |
12.47 |
| 2026-06-12 12:00 |
02:54:53.53 |
+12:46:32.1 |
HIP 13557 |
10.56 |
| 2026-06-13 00:00 |
02:55:24.22 |
+12:48:38.3 |
HIP 13557 |
13.74 |
| 2026-06-13 12:00 |
02:55:54.88 |
+12:50:43.7 |
HIP 13557 |
19.66 |
| 2026-06-14 00:00 |
02:56:25.50 |
+12:52:48.6 |
HIP 13638 |
21.42 |
| 2026-06-14 12:00 |
02:56:56.07 |
+12:54:52.9 |
HIP 13638 |
24.89 |
| 2026-06-15 00:00 |
02:57:26.60 |
+12:56:56.5 |
HIP 13638 |
29.99 |
| 2026-06-15 12:00 |
02:57:57.09 |
+12:58:59.5 |
HIP 13638 |
36.03 |
| 2026-06-16 00:00 |
02:58:27.54 |
+13:01:01.8 |
HIP 14037 |
33.80 |
| 2026-06-16 12:00 |
02:58:57.94 |
+13:03:03.6 |
HIP 14037 |
26.63 |
| 2026-06-17 00:00 |
02:59:28.30 |
+13:05:04.7 |
HIP 14037 |
19.86 |
| 2026-06-17 12:00 |
02:59:58.61 |
+13:07:05.1 |
HIP 14037 |
14.05 |
| 2026-06-18 00:00 |
03:00:28.87 |
+13:09:05.0 |
HIP 14037 |
10.83 |
| 2026-06-18 12:00 |
03:00:59.09 |
+13:11:04.1 |
HIP 14037 |
12.39 |
| 2026-06-19 00:00 |
03:01:29.26 |
+13:13:02.7 |
HIP 14111 |
6.71 |
| 2026-06-19 12:00 |
03:01:59.38 |
+13:15:00.6 |
HIP 14111 |
0.99 |
| 2026-06-20 00:00 |
03:02:29.45 |
+13:16:57.8 |
HIP 14111 |
8.48 |
| 2026-06-20 12:00 |
03:02:59.47 |
+13:18:54.4 |
HIP 14111 |
16.03 |
| 2026-06-21 00:00 |
03:03:29.44 |
+13:20:50.4 |
HIP 14111 |
23.57 |
| 2026-06-21 12:00 |
03:03:59.35 |
+13:22:45.7 |
HIP 14329 |
27.90 |
| 2026-06-22 00:00 |
03:04:29.22 |
+13:24:40.4 |
HIP 14329 |
23.70 |