C/2012 S4 (PANSTARRS)
メタデータ
| 項目 |
値 |
| Designation |
C/2012 S4 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-06-28T00:33:42.019200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:22Z |
| Obs used |
924 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
8.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2013-04-24.0000000 |
| e |
0.99998199 |
| q (au) |
4.348728 |
| a (au) |
241497.706412 |
| i (deg) |
126.541334 |
| Ω (om, deg) |
173.103524 |
| ω (w, deg) |
163.615485 |
| M (ma, deg) |
359.999999 |
等級
散乱 + 全体線形
$$
M_a = (7.720 + 4.989\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.720 |
| n |
4.989 |
| gf |
0.997 |
| gb |
-0.512 |
| k |
0.800 |
| δ90 |
9.110 |
| 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) |
| 2026-02-03 00:00 |
13:21:11.91 |
-59:35:51.7 |
HIP 65108 |
11.49 |
| 2026-02-03 12:00 |
13:21:08.35 |
-59:36:27.8 |
HIP 65108 |
10.76 |
| 2026-02-04 00:00 |
13:21:04.72 |
-59:37:03.6 |
HIP 65108 |
10.03 |
| 2026-02-04 12:00 |
13:21:01.02 |
-59:37:39.1 |
HIP 65108 |
9.31 |
| 2026-02-05 00:00 |
13:20:57.25 |
-59:38:14.3 |
HIP 65108 |
8.60 |
| 2026-02-05 12:00 |
13:20:53.42 |
-59:38:49.1 |
HIP 65108 |
7.89 |
| 2026-02-06 00:00 |
13:20:49.51 |
-59:39:23.7 |
HIP 65108 |
7.20 |
| 2026-02-06 12:00 |
13:20:45.54 |
-59:39:57.9 |
HIP 65108 |
6.53 |
| 2026-02-07 00:00 |
13:20:41.50 |
-59:40:31.9 |
HIP 65108 |
5.89 |
| 2026-02-07 12:00 |
13:20:37.39 |
-59:41:05.5 |
HIP 65108 |
5.28 |
| 2026-02-08 00:00 |
13:20:33.21 |
-59:41:38.8 |
HIP 65108 |
4.72 |
| 2026-02-08 12:00 |
13:20:28.96 |
-59:42:11.8 |
HIP 65108 |
4.24 |
| 2026-02-09 00:00 |
13:20:24.65 |
-59:42:44.4 |
HIP 65108 |
3.86 |
| 2026-02-09 12:00 |
13:20:20.27 |
-59:43:16.7 |
HIP 65108 |
3.61 |
| 2026-02-10 00:00 |
13:20:15.82 |
-59:43:48.7 |
HIP 65108 |
3.52 |
| 2026-02-10 12:00 |
13:20:11.31 |
-59:44:20.3 |
HIP 65108 |
3.61 |
| 2026-02-11 00:00 |
13:20:06.73 |
-59:44:51.6 |
HIP 65108 |
3.87 |
| 2026-02-11 12:00 |
13:20:02.08 |
-59:45:22.5 |
HIP 65108 |
4.27 |
| 2026-02-12 00:00 |
13:19:57.37 |
-59:45:53.1 |
HIP 65108 |
4.77 |
| 2026-02-12 12:00 |
13:19:52.59 |
-59:46:23.3 |
HIP 65108 |
5.35 |
| 2026-02-13 00:00 |
13:19:47.75 |
-59:46:53.1 |
HIP 65108 |
5.98 |
| 2026-02-13 12:00 |
13:19:42.84 |
-59:47:22.6 |
HIP 65108 |
6.65 |
| 2026-02-14 00:00 |
13:19:37.87 |
-59:47:51.7 |
HIP 65108 |
7.35 |
| 2026-02-14 12:00 |
13:19:32.83 |
-59:48:20.5 |
HIP 65108 |
8.07 |
| 2026-02-15 00:00 |
13:19:27.73 |
-59:48:48.9 |
HIP 65108 |
8.82 |
| 2026-02-15 12:00 |
13:19:22.56 |
-59:49:16.9 |
HIP 65108 |
9.57 |
| 2026-02-16 00:00 |
13:19:17.34 |
-59:49:44.5 |
HIP 65108 |
10.34 |
| 2026-02-16 12:00 |
13:19:12.05 |
-59:50:11.8 |
HIP 65108 |
11.12 |
| 2026-02-17 00:00 |
13:19:06.69 |
-59:50:38.6 |
HIP 65108 |
11.91 |
| 2026-02-17 12:00 |
13:19:01.28 |
-59:51:05.1 |
HIP 65108 |
12.70 |
| 2026-02-18 00:00 |
13:18:55.80 |
-59:51:31.1 |
HIP 65108 |
13.50 |
| 2026-02-18 12:00 |
13:18:50.26 |
-59:51:56.8 |
HIP 65108 |
14.31 |
| 2026-02-19 00:00 |
13:18:44.66 |
-59:52:22.1 |
HIP 65108 |
15.12 |
| 2026-02-19 12:00 |
13:18:39.00 |
-59:52:46.9 |
HIP 64913 |
15.91 |
| 2026-02-20 00:00 |
13:18:33.28 |
-59:53:11.4 |
HIP 64913 |
16.21 |
| 2026-02-20 12:00 |
13:18:27.50 |
-59:53:35.4 |
HIP 64913 |
16.55 |
| 2026-02-21 00:00 |
13:18:21.66 |
-59:53:59.1 |
HIP 64913 |
16.91 |
| 2026-02-21 12:00 |
13:18:15.76 |
-59:54:22.3 |
HIP 64913 |
17.30 |
| 2026-02-22 00:00 |
13:18:09.80 |
-59:54:45.1 |
HIP 64913 |
17.71 |
| 2026-02-22 12:00 |
13:18:03.79 |
-59:55:07.5 |
HIP 64913 |
18.14 |
| 2026-02-23 00:00 |
13:17:57.72 |
-59:55:29.4 |
HIP 64913 |
18.60 |
| 2026-02-23 12:00 |
13:17:51.59 |
-59:55:51.0 |
HIP 64913 |
19.08 |
| 2026-02-24 00:00 |
13:17:45.41 |
-59:56:12.1 |
HIP 64913 |
19.58 |