メタデータ
| 項目 |
値 |
| Designation |
C/2012 E2 (SWAN) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-03-15T00:41:51.241920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:04Z |
| Obs used |
43 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2012-03-13.0000000 |
| e |
1.00049131 |
| q (au) |
0.006962 |
| a (au) |
-14.169573 |
| i (deg) |
144.430741 |
| Ω (om, deg) |
6.576461 |
| ω (w, deg) |
82.412294 |
| M (ma, deg) |
-0.037494 |
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) |
| 2026-07-29 00:00 |
07:04:24.20 |
-11:47:14.7 |
HIP 34133 |
16.17 |
| 2026-07-29 12:00 |
07:04:26.86 |
-11:47:27.3 |
HIP 34133 |
16.25 |
| 2026-07-30 00:00 |
07:04:29.51 |
-11:47:40.0 |
HIP 34133 |
16.36 |
| 2026-07-30 12:00 |
07:04:32.16 |
-11:47:52.8 |
HIP 34133 |
16.51 |
| 2026-07-31 00:00 |
07:04:34.80 |
-11:48:05.9 |
HIP 34133 |
16.68 |
| 2026-07-31 12:00 |
07:04:37.42 |
-11:48:19.1 |
HIP 34133 |
16.88 |
| 2026-08-01 00:00 |
07:04:40.04 |
-11:48:32.5 |
HIP 34133 |
17.10 |
| 2026-08-01 12:00 |
07:04:42.65 |
-11:48:46.1 |
HIP 34133 |
17.36 |
| 2026-08-02 00:00 |
07:04:45.25 |
-11:48:59.8 |
HIP 34133 |
17.63 |
| 2026-08-02 12:00 |
07:04:47.84 |
-11:49:13.7 |
HIP 34133 |
17.94 |
| 2026-08-03 00:00 |
07:04:50.42 |
-11:49:27.8 |
HIP 34133 |
18.26 |
| 2026-08-03 12:00 |
07:04:52.99 |
-11:49:42.0 |
HIP 34133 |
18.61 |
| 2026-08-04 00:00 |
07:04:55.54 |
-11:49:56.4 |
HIP 34133 |
18.97 |
| 2026-08-04 12:00 |
07:04:58.09 |
-11:50:11.0 |
HIP 34133 |
19.36 |
| 2026-08-05 00:00 |
07:05:00.63 |
-11:50:25.8 |
HIP 34133 |
19.76 |
| 2026-08-05 12:00 |
07:05:03.15 |
-11:50:40.7 |
HIP 34133 |
20.17 |
| 2026-08-06 00:00 |
07:05:05.67 |
-11:50:55.7 |
HIP 34133 |
20.60 |
| 2026-08-06 12:00 |
07:05:08.17 |
-11:51:11.0 |
HIP 34133 |
21.05 |
| 2026-08-07 00:00 |
07:05:10.66 |
-11:51:26.4 |
HIP 34133 |
21.51 |
| 2026-08-07 12:00 |
07:05:13.14 |
-11:51:41.9 |
HIP 34133 |
21.98 |
| 2026-08-08 00:00 |
07:05:15.61 |
-11:51:57.7 |
HIP 34133 |
22.46 |
| 2026-08-08 12:00 |
07:05:18.06 |
-11:52:13.5 |
HIP 34133 |
22.95 |
| 2026-08-09 00:00 |
07:05:20.51 |
-11:52:29.6 |
HIP 34133 |
23.45 |
| 2026-08-09 12:00 |
07:05:22.94 |
-11:52:45.8 |
HIP 34133 |
23.96 |
| 2026-08-10 00:00 |
07:05:25.35 |
-11:53:02.1 |
HIP 34133 |
24.47 |
| 2026-08-10 12:00 |
07:05:27.76 |
-11:53:18.6 |
HIP 34133 |
24.99 |
| 2026-08-11 00:00 |
07:05:30.15 |
-11:53:35.3 |
HIP 34133 |
25.52 |
| 2026-08-11 12:00 |
07:05:32.53 |
-11:53:52.1 |
HIP 34287 |
25.84 |
| 2026-08-12 00:00 |
07:05:34.90 |
-11:54:09.1 |
HIP 34287 |
25.76 |
| 2026-08-12 12:00 |
07:05:37.25 |
-11:54:26.2 |
HIP 34178 |
25.63 |
| 2026-08-13 00:00 |
07:05:39.59 |
-11:54:43.5 |
HIP 34178 |
25.47 |
| 2026-08-13 12:00 |
07:05:41.91 |
-11:55:00.9 |
HIP 34178 |
25.32 |
| 2026-08-14 00:00 |
07:05:44.22 |
-11:55:18.5 |
HIP 34178 |
25.18 |
| 2026-08-14 12:00 |
07:05:46.52 |
-11:55:36.2 |
HIP 34178 |
25.05 |
| 2026-08-15 00:00 |
07:05:48.80 |
-11:55:54.1 |
HIP 34178 |
24.94 |
| 2026-08-15 12:00 |
07:05:51.07 |
-11:56:12.1 |
HIP 34178 |
24.83 |
| 2026-08-16 00:00 |
07:05:53.32 |
-11:56:30.3 |
HIP 34178 |
24.74 |
| 2026-08-16 12:00 |
07:05:55.56 |
-11:56:48.6 |
HIP 34178 |
24.66 |
| 2026-08-17 00:00 |
07:05:57.78 |
-11:57:07.0 |
HIP 34178 |
24.60 |
| 2026-08-17 12:00 |
07:05:59.99 |
-11:57:25.6 |
HIP 34178 |
24.54 |
| 2026-08-18 00:00 |
07:06:02.18 |
-11:57:44.3 |
HIP 34178 |
24.50 |
| 2026-08-18 12:00 |
07:06:04.36 |
-11:58:03.1 |
HIP 34178 |
24.47 |
| 2026-08-19 00:00 |
07:06:06.52 |
-11:58:22.1 |
HIP 34178 |
24.45 |