メタデータ
| 項目 |
値 |
| Designation |
P/2012 U2 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2012-12-04T06:27:38.750400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:26Z |
| Obs used |
36 |
| NEO |
- |
| M1 |
12.100 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2012-11-14.0000000 |
| e |
0.50656873 |
| q (au) |
3.627785 |
| a (au) |
7.352159 |
| i (deg) |
10.534475 |
| Ω (om, deg) |
186.863069 |
| ω (w, deg) |
229.534876 |
| M (ma, deg) |
358.997883 |
等級
散乱 + 全体線形
$$
M_a = (9.078 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
9.078 |
| n |
6.000 |
| gf |
0.801 |
| gb |
-0.500 |
| k |
0.973 |
| δ90 |
1.000 |
| 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) |
| 2026-03-26 00:00 |
17:59:38.03 |
-12:44:15.1 |
HIP 88090 |
17.79 |
| 2026-03-26 12:00 |
17:59:40.37 |
-12:43:38.8 |
HIP 88090 |
18.48 |
| 2026-03-27 00:00 |
17:59:42.61 |
-12:43:02.4 |
HIP 88090 |
19.17 |
| 2026-03-27 12:00 |
17:59:44.74 |
-12:42:25.9 |
HIP 88171 |
19.73 |
| 2026-03-28 00:00 |
17:59:46.75 |
-12:41:49.5 |
HIP 88171 |
20.01 |
| 2026-03-28 12:00 |
17:59:48.66 |
-12:41:13.0 |
HIP 88171 |
20.33 |
| 2026-03-29 00:00 |
17:59:50.47 |
-12:40:36.4 |
HIP 88171 |
20.68 |
| 2026-03-29 12:00 |
17:59:52.16 |
-12:39:59.8 |
HIP 88171 |
21.06 |
| 2026-03-30 00:00 |
17:59:53.74 |
-12:39:23.3 |
HIP 88171 |
21.47 |
| 2026-03-30 12:00 |
17:59:55.22 |
-12:38:46.6 |
HIP 88171 |
21.91 |
| 2026-03-31 00:00 |
17:59:56.59 |
-12:38:10.0 |
HIP 88171 |
22.37 |
| 2026-03-31 12:00 |
17:59:57.84 |
-12:37:33.3 |
HIP 88171 |
22.85 |
| 2026-04-01 00:00 |
17:59:58.99 |
-12:36:56.7 |
HIP 88171 |
23.35 |
| 2026-04-01 12:00 |
18:00:00.03 |
-12:36:20.0 |
HIP 88171 |
23.86 |
| 2026-04-02 00:00 |
18:00:00.97 |
-12:35:43.3 |
HIP 88171 |
24.39 |
| 2026-04-02 12:00 |
18:00:01.79 |
-12:35:06.6 |
HIP 88171 |
24.94 |
| 2026-04-03 00:00 |
18:00:02.50 |
-12:34:29.9 |
HIP 88171 |
25.49 |
| 2026-04-03 12:00 |
18:00:03.10 |
-12:33:53.1 |
HIP 88117 |
25.10 |
| 2026-04-04 00:00 |
18:00:03.60 |
-12:33:16.4 |
HIP 88117 |
24.51 |
| 2026-04-04 12:00 |
18:00:03.98 |
-12:32:39.7 |
HIP 88117 |
23.92 |
| 2026-04-05 00:00 |
18:00:04.25 |
-12:32:03.0 |
HIP 88117 |
23.33 |
| 2026-04-05 12:00 |
18:00:04.42 |
-12:31:26.3 |
HIP 88117 |
22.74 |
| 2026-04-06 00:00 |
18:00:04.47 |
-12:30:49.6 |
HIP 88117 |
22.14 |
| 2026-04-06 12:00 |
18:00:04.42 |
-12:30:12.9 |
HIP 88117 |
21.53 |
| 2026-04-07 00:00 |
18:00:04.25 |
-12:29:36.3 |
HIP 88117 |
20.92 |
| 2026-04-07 12:00 |
18:00:03.97 |
-12:28:59.6 |
HIP 88117 |
20.31 |
| 2026-04-08 00:00 |
18:00:03.59 |
-12:28:23.0 |
HIP 88117 |
19.70 |
| 2026-04-08 12:00 |
18:00:03.09 |
-12:27:46.4 |
HIP 88117 |
19.07 |
| 2026-04-09 00:00 |
18:00:02.49 |
-12:27:09.8 |
HIP 88117 |
18.45 |
| 2026-04-09 12:00 |
18:00:01.77 |
-12:26:33.3 |
HIP 88117 |
17.82 |
| 2026-04-10 00:00 |
18:00:00.94 |
-12:25:56.8 |
HIP 88117 |
17.18 |
| 2026-04-10 12:00 |
18:00:00.01 |
-12:25:20.3 |
HIP 88117 |
16.54 |
| 2026-04-11 00:00 |
17:59:58.96 |
-12:24:43.8 |
HIP 88117 |
15.90 |
| 2026-04-11 12:00 |
17:59:57.80 |
-12:24:07.5 |
HIP 88117 |
15.26 |
| 2026-04-12 00:00 |
17:59:56.54 |
-12:23:31.1 |
HIP 88117 |
14.61 |
| 2026-04-12 12:00 |
17:59:55.16 |
-12:22:54.8 |
HIP 88117 |
13.97 |
| 2026-04-13 00:00 |
17:59:53.67 |
-12:22:18.6 |
HIP 88117 |
13.33 |
| 2026-04-13 12:00 |
17:59:52.07 |
-12:21:42.4 |
HIP 88117 |
12.69 |
| 2026-04-14 00:00 |
17:59:50.37 |
-12:21:06.2 |
HIP 88117 |
12.07 |
| 2026-04-14 12:00 |
17:59:48.55 |
-12:20:30.2 |
HIP 88117 |
11.45 |
| 2026-04-15 00:00 |
17:59:46.62 |
-12:19:54.1 |
HIP 88117 |
10.86 |
| 2026-04-15 12:00 |
17:59:44.59 |
-12:19:18.2 |
HIP 88117 |
10.29 |
| 2026-04-16 00:00 |
17:59:42.44 |
-12:18:42.3 |
HIP 88117 |
9.76 |