C/2012 A1 (PANSTARRS)
メタデータ
| 項目 |
値 |
| Designation |
C/2012 A1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-11-29T15:21:03.746880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:59Z |
| Obs used |
322 |
| NEO |
- |
| M1 |
10.100 |
| K1 |
5.250 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2012-12-26.0000000 |
| e |
1.00119496 |
| q (au) |
7.604434 |
| a (au) |
-6363.768778 |
| i (deg) |
120.900017 |
| Ω (om, deg) |
277.972039 |
| ω (w, deg) |
191.758696 |
| M (ma, deg) |
-0.000657 |
等級
散乱 + 全体線形
$$
M_a = (9.596 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
9.596 |
| n |
2.000 |
| gf |
0.822 |
| gb |
-0.955 |
| k |
1.000 |
| δ90 |
2.186 |
| 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 |
22:37:20.67 |
-56:46:01.8 |
HIP 111969 |
34.94 |
| 2026-02-03 12:00 |
22:37:26.74 |
-56:45:21.8 |
HIP 111969 |
34.67 |
| 2026-02-04 00:00 |
22:37:32.83 |
-56:44:42.1 |
HIP 111969 |
34.42 |
| 2026-02-04 12:00 |
22:37:38.95 |
-56:44:02.8 |
HIP 111969 |
34.19 |
| 2026-02-05 00:00 |
22:37:45.09 |
-56:43:23.8 |
HIP 111969 |
33.99 |
| 2026-02-05 12:00 |
22:37:51.26 |
-56:42:45.2 |
HIP 112005 |
33.72 |
| 2026-02-06 00:00 |
22:37:57.44 |
-56:42:07.0 |
HIP 112005 |
33.40 |
| 2026-02-06 12:00 |
22:38:03.65 |
-56:41:29.1 |
HIP 112005 |
33.10 |
| 2026-02-07 00:00 |
22:38:09.87 |
-56:40:51.6 |
HIP 112005 |
32.83 |
| 2026-02-07 12:00 |
22:38:16.12 |
-56:40:14.4 |
HIP 112005 |
32.58 |
| 2026-02-08 00:00 |
22:38:22.39 |
-56:39:37.7 |
HIP 112005 |
32.36 |
| 2026-02-08 12:00 |
22:38:28.67 |
-56:39:01.3 |
HIP 112005 |
32.16 |
| 2026-02-09 00:00 |
22:38:34.97 |
-56:38:25.2 |
HIP 112005 |
31.99 |
| 2026-02-09 12:00 |
22:38:41.29 |
-56:37:49.6 |
HIP 112005 |
31.85 |
| 2026-02-10 00:00 |
22:38:47.63 |
-56:37:14.3 |
HIP 112005 |
31.74 |
| 2026-02-10 12:00 |
22:38:53.99 |
-56:36:39.4 |
HIP 112005 |
31.65 |
| 2026-02-11 00:00 |
22:39:00.36 |
-56:36:04.9 |
HIP 112005 |
31.59 |
| 2026-02-11 12:00 |
22:39:06.75 |
-56:35:30.8 |
HIP 112005 |
31.56 |
| 2026-02-12 00:00 |
22:39:13.15 |
-56:34:57.0 |
HIP 112005 |
31.55 |
| 2026-02-12 12:00 |
22:39:19.57 |
-56:34:23.7 |
HIP 112005 |
31.58 |
| 2026-02-13 00:00 |
22:39:26.00 |
-56:33:50.7 |
HIP 112005 |
31.63 |
| 2026-02-13 12:00 |
22:39:32.45 |
-56:33:18.1 |
HIP 112005 |
31.70 |
| 2026-02-14 00:00 |
22:39:38.91 |
-56:32:45.9 |
HIP 112005 |
31.81 |
| 2026-02-14 12:00 |
22:39:45.38 |
-56:32:14.2 |
HIP 112005 |
31.94 |
| 2026-02-15 00:00 |
22:39:51.86 |
-56:31:42.8 |
HIP 112005 |
32.09 |
| 2026-02-15 12:00 |
22:39:58.36 |
-56:31:11.8 |
HIP 112005 |
32.28 |
| 2026-02-16 00:00 |
22:40:04.87 |
-56:30:41.2 |
HIP 112005 |
32.48 |
| 2026-02-16 12:00 |
22:40:11.38 |
-56:30:11.1 |
HIP 112005 |
32.71 |
| 2026-02-17 00:00 |
22:40:17.91 |
-56:29:41.3 |
HIP 112005 |
32.96 |
| 2026-02-17 12:00 |
22:40:24.45 |
-56:29:12.0 |
HIP 112005 |
33.24 |
| 2026-02-18 00:00 |
22:40:31.00 |
-56:28:43.0 |
HIP 112005 |
33.54 |
| 2026-02-18 12:00 |
22:40:37.55 |
-56:28:14.5 |
HIP 112005 |
33.85 |
| 2026-02-19 00:00 |
22:40:44.11 |
-56:27:46.4 |
HIP 112005 |
34.19 |
| 2026-02-19 12:00 |
22:40:50.68 |
-56:27:18.7 |
HIP 112005 |
34.55 |
| 2026-02-20 00:00 |
22:40:57.26 |
-56:26:51.4 |
HIP 112285 |
34.92 |
| 2026-02-20 12:00 |
22:41:03.84 |
-56:26:24.6 |
HIP 112285 |
33.91 |
| 2026-02-21 00:00 |
22:41:10.43 |
-56:25:58.1 |
HIP 112285 |
32.90 |
| 2026-02-21 12:00 |
22:41:17.03 |
-56:25:32.1 |
HIP 112285 |
31.89 |
| 2026-02-22 00:00 |
22:41:23.63 |
-56:25:06.5 |
HIP 112285 |
30.88 |
| 2026-02-22 12:00 |
22:41:30.23 |
-56:24:41.4 |
HIP 112285 |
29.88 |
| 2026-02-23 00:00 |
22:41:36.83 |
-56:24:16.6 |
HIP 112285 |
28.89 |
| 2026-02-23 12:00 |
22:41:43.44 |
-56:23:52.3 |
HIP 112285 |
27.89 |
| 2026-02-24 00:00 |
22:41:50.05 |
-56:23:28.4 |
HIP 112285 |
26.90 |