メタデータ
| 項目 |
値 |
| Designation |
P/2008 Y12 (SOHO) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2008-12-22T11:21:24.419520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:27Z |
| Obs used |
76 |
| NEO |
Yes |
| M1 |
- |
| K1 |
- |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2010-10-24.0000000 |
| e |
0.97876170 |
| q (au) |
0.065376 |
| a (au) |
3.078198 |
| i (deg) |
23.345371 |
| Ω (om, deg) |
312.574737 |
| ω (w, deg) |
146.622073 |
| M (ma, deg) |
122.370129 |
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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
19:02:16.54 |
-40:28:39.3 |
HIP 93458 |
11.46 |
| 2026-06-01 12:00 |
19:01:46.72 |
-40:30:10.3 |
HIP 93458 |
10.01 |
| 2026-06-02 00:00 |
19:01:16.67 |
-40:31:40.1 |
HIP 93458 |
11.78 |
| 2026-06-02 12:00 |
19:00:46.41 |
-40:33:08.9 |
HIP 93250 |
13.03 |
| 2026-06-03 00:00 |
19:00:15.92 |
-40:34:36.4 |
HIP 93250 |
7.10 |
| 2026-06-03 12:00 |
18:59:45.22 |
-40:36:02.8 |
HIP 93250 |
1.50 |
| 2026-06-04 00:00 |
18:59:14.31 |
-40:37:28.0 |
HIP 93250 |
5.15 |
| 2026-06-04 12:00 |
18:58:43.19 |
-40:38:51.9 |
HIP 93250 |
11.15 |
| 2026-06-05 00:00 |
18:58:11.87 |
-40:40:14.5 |
HIP 93250 |
17.23 |
| 2026-06-05 12:00 |
18:57:40.35 |
-40:41:35.9 |
HIP 92971 |
15.41 |
| 2026-06-06 00:00 |
18:57:08.63 |
-40:42:56.0 |
HIP 92971 |
11.23 |
| 2026-06-06 12:00 |
18:56:36.72 |
-40:44:14.8 |
HIP 92971 |
9.49 |
| 2026-06-07 00:00 |
18:56:04.62 |
-40:45:32.2 |
HIP 92971 |
11.43 |
| 2026-06-07 12:00 |
18:55:32.34 |
-40:46:48.3 |
HIP 92777 |
13.77 |
| 2026-06-08 00:00 |
18:54:59.88 |
-40:48:03.0 |
HIP 92777 |
7.50 |
| 2026-06-08 12:00 |
18:54:27.24 |
-40:49:16.3 |
HIP 92777 |
1.21 |
| 2026-06-09 00:00 |
18:53:54.43 |
-40:50:28.1 |
HIP 92777 |
5.12 |
| 2026-06-09 12:00 |
18:53:21.45 |
-40:51:38.6 |
HIP 92777 |
11.46 |
| 2026-06-10 00:00 |
18:52:48.30 |
-40:52:47.5 |
HIP 92777 |
17.83 |
| 2026-06-10 12:00 |
18:52:15.00 |
-40:53:55.0 |
HIP 92621 |
16.74 |
| 2026-06-11 00:00 |
18:51:41.55 |
-40:55:01.0 |
HIP 92490 |
11.79 |
| 2026-06-11 12:00 |
18:51:07.94 |
-40:56:05.5 |
HIP 92490 |
7.82 |
| 2026-06-12 00:00 |
18:50:34.19 |
-40:57:08.4 |
HIP 92487 |
8.07 |
| 2026-06-12 12:00 |
18:50:00.30 |
-40:58:09.8 |
HIP 92487 |
12.35 |
| 2026-06-13 00:00 |
18:49:26.27 |
-40:59:09.6 |
HIP 92487 |
18.02 |
| 2026-06-13 12:00 |
18:48:52.11 |
-41:00:07.8 |
HIP 92310 |
20.09 |
| 2026-06-14 00:00 |
18:48:17.83 |
-41:01:04.4 |
HIP 92158 |
17.05 |
| 2026-06-14 12:00 |
18:47:43.43 |
-41:01:59.4 |
HIP 92158 |
11.29 |
| 2026-06-15 00:00 |
18:47:08.91 |
-41:02:52.8 |
HIP 92158 |
7.07 |
| 2026-06-15 12:00 |
18:46:34.29 |
-41:03:44.5 |
HIP 92158 |
7.70 |
| 2026-06-16 00:00 |
18:45:59.55 |
-41:04:34.6 |
HIP 92158 |
12.48 |
| 2026-06-16 12:00 |
18:45:24.72 |
-41:05:23.0 |
HIP 92158 |
18.45 |
| 2026-06-17 00:00 |
18:44:49.80 |
-41:06:09.7 |
HIP 91956 |
20.05 |
| 2026-06-17 12:00 |
18:44:14.79 |
-41:06:54.6 |
HIP 91874 |
19.66 |
| 2026-06-18 00:00 |
18:43:39.69 |
-41:07:37.9 |
HIP 91874 |
19.71 |
| 2026-06-18 12:00 |
18:43:04.52 |
-41:08:19.5 |
HIP 91874 |
21.87 |
| 2026-06-19 00:00 |
18:42:29.28 |
-41:08:59.3 |
HIP 91631 |
22.40 |
| 2026-06-19 12:00 |
18:41:53.97 |
-41:09:37.4 |
HIP 91631 |
18.36 |
| 2026-06-20 00:00 |
18:41:18.60 |
-41:10:13.7 |
HIP 91631 |
16.19 |
| 2026-06-20 12:00 |
18:40:43.17 |
-41:10:48.3 |
HIP 91551 |
13.83 |
| 2026-06-21 00:00 |
18:40:07.69 |
-41:11:21.1 |
HIP 91551 |
13.05 |
| 2026-06-21 12:00 |
18:39:32.17 |
-41:11:52.1 |
HIP 91481 |
14.53 |
| 2026-06-22 00:00 |
18:38:56.61 |
-41:12:21.4 |
HIP 91481 |
15.21 |