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) |
| 2026-03-26 00:00 |
06:56:31.06 |
-12:30:39.4 |
HIP 33489 |
19.74 |
| 2026-03-26 12:00 |
06:56:30.61 |
-12:30:13.1 |
HIP 33489 |
19.60 |
| 2026-03-27 00:00 |
06:56:30.19 |
-12:29:46.7 |
HIP 33489 |
19.47 |
| 2026-03-27 12:00 |
06:56:29.80 |
-12:29:20.4 |
HIP 33489 |
19.34 |
| 2026-03-28 00:00 |
06:56:29.43 |
-12:28:54.1 |
HIP 33489 |
19.22 |
| 2026-03-28 12:00 |
06:56:29.09 |
-12:28:27.8 |
HIP 33489 |
19.09 |
| 2026-03-29 00:00 |
06:56:28.78 |
-12:28:01.5 |
HIP 33489 |
18.98 |
| 2026-03-29 12:00 |
06:56:28.49 |
-12:27:35.3 |
HIP 33489 |
18.86 |
| 2026-03-30 00:00 |
06:56:28.23 |
-12:27:09.1 |
HIP 33489 |
18.75 |
| 2026-03-30 12:00 |
06:56:28.00 |
-12:26:42.9 |
HIP 33489 |
18.65 |
| 2026-03-31 00:00 |
06:56:27.79 |
-12:26:16.7 |
HIP 33489 |
18.55 |
| 2026-03-31 12:00 |
06:56:27.61 |
-12:25:50.6 |
HIP 33489 |
18.45 |
| 2026-04-01 00:00 |
06:56:27.45 |
-12:25:24.5 |
HIP 33489 |
18.35 |
| 2026-04-01 12:00 |
06:56:27.32 |
-12:24:58.5 |
HIP 33489 |
18.26 |
| 2026-04-02 00:00 |
06:56:27.22 |
-12:24:32.5 |
HIP 33489 |
18.18 |
| 2026-04-02 12:00 |
06:56:27.14 |
-12:24:06.5 |
HIP 33489 |
18.10 |
| 2026-04-03 00:00 |
06:56:27.09 |
-12:23:40.6 |
HIP 33489 |
18.02 |
| 2026-04-03 12:00 |
06:56:27.07 |
-12:23:14.7 |
HIP 33489 |
17.94 |
| 2026-04-04 00:00 |
06:56:27.07 |
-12:22:48.8 |
HIP 33489 |
17.87 |
| 2026-04-04 12:00 |
06:56:27.09 |
-12:22:23.0 |
HIP 33489 |
17.81 |
| 2026-04-05 00:00 |
06:56:27.15 |
-12:21:57.3 |
HIP 33489 |
17.75 |
| 2026-04-05 12:00 |
06:56:27.23 |
-12:21:31.6 |
HIP 33489 |
17.69 |
| 2026-04-06 00:00 |
06:56:27.33 |
-12:21:05.9 |
HIP 33489 |
17.63 |
| 2026-04-06 12:00 |
06:56:27.46 |
-12:20:40.3 |
HIP 33489 |
17.58 |
| 2026-04-07 00:00 |
06:56:27.62 |
-12:20:14.8 |
HIP 33489 |
17.53 |
| 2026-04-07 12:00 |
06:56:27.81 |
-12:19:49.3 |
HIP 33489 |
17.49 |
| 2026-04-08 00:00 |
06:56:28.01 |
-12:19:23.9 |
HIP 33489 |
17.45 |
| 2026-04-08 12:00 |
06:56:28.25 |
-12:18:58.5 |
HIP 33489 |
17.42 |
| 2026-04-09 00:00 |
06:56:28.51 |
-12:18:33.2 |
HIP 33489 |
17.39 |
| 2026-04-09 12:00 |
06:56:28.80 |
-12:18:08.0 |
HIP 33489 |
17.36 |
| 2026-04-10 00:00 |
06:56:29.11 |
-12:17:42.8 |
HIP 33489 |
17.34 |
| 2026-04-10 12:00 |
06:56:29.45 |
-12:17:17.7 |
HIP 33489 |
17.32 |
| 2026-04-11 00:00 |
06:56:29.81 |
-12:16:52.7 |
HIP 33489 |
17.31 |
| 2026-04-11 12:00 |
06:56:30.20 |
-12:16:27.7 |
HIP 33489 |
17.30 |
| 2026-04-12 00:00 |
06:56:30.62 |
-12:16:02.8 |
HIP 33489 |
17.29 |
| 2026-04-12 12:00 |
06:56:31.06 |
-12:15:38.0 |
HIP 33489 |
17.29 |
| 2026-04-13 00:00 |
06:56:31.52 |
-12:15:13.3 |
HIP 33489 |
17.29 |
| 2026-04-13 12:00 |
06:56:32.01 |
-12:14:48.6 |
HIP 33489 |
17.30 |
| 2026-04-14 00:00 |
06:56:32.53 |
-12:14:24.0 |
HIP 33489 |
17.31 |
| 2026-04-14 12:00 |
06:56:33.07 |
-12:13:59.5 |
HIP 33489 |
17.32 |
| 2026-04-15 00:00 |
06:56:33.64 |
-12:13:35.1 |
HIP 33489 |
17.34 |
| 2026-04-15 12:00 |
06:56:34.23 |
-12:13:10.8 |
HIP 33489 |
17.37 |
| 2026-04-16 00:00 |
06:56:34.85 |
-12:12:46.5 |
HIP 33489 |
17.40 |