メタデータ
| 項目 |
値 |
| Designation |
C/2023 A2 (SWAN) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2023-01-20T09:20:12.062400Z |
| Orbit solution date (soln_date, UTC) |
2026-03-12T09:30:38Z |
| Obs used |
159 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
20.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2023-01-06T00:00:00Z |
| Discovery magnitude (MPC) |
- |
| Discovery observatory (MPC) |
249 · SOHO |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2023-03-06.0000000 |
| e |
0.99829132 |
| q (au) |
0.947460 |
| a (au) |
554.499318 |
| i (deg) |
94.708355 |
| Ω (om, deg) |
94.471088 |
| ω (w, deg) |
142.583308 |
| M (ma, deg) |
0.003367 |
等級
散乱 + 全体線形
$$
M_a = (14.827 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.827 |
| n |
6.000 |
| gf |
0.991 |
| gb |
-1.000 |
| k |
0.840 |
| δ90 |
10.000 |
| 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) |
| 2026-06-01 00:00 |
06:22:33.92 |
-42:45:11.1 |
HIP 30476 |
21.08 |
| 2026-06-01 12:00 |
06:22:45.99 |
-42:44:03.3 |
HIP 30476 |
19.33 |
| 2026-06-02 00:00 |
06:22:58.09 |
-42:42:56.6 |
HIP 30476 |
17.75 |
| 2026-06-02 12:00 |
06:23:10.22 |
-42:41:50.8 |
HIP 30476 |
16.39 |
| 2026-06-03 00:00 |
06:23:22.38 |
-42:40:46.1 |
HIP 30476 |
15.28 |
| 2026-06-03 12:00 |
06:23:34.56 |
-42:39:42.3 |
HIP 30476 |
14.51 |
| 2026-06-04 00:00 |
06:23:46.77 |
-42:38:39.6 |
HIP 30476 |
14.11 |
| 2026-06-04 12:00 |
06:23:59.00 |
-42:37:37.9 |
HIP 30476 |
14.13 |
| 2026-06-05 00:00 |
06:24:11.26 |
-42:36:37.2 |
HIP 30476 |
14.55 |
| 2026-06-05 12:00 |
06:24:23.55 |
-42:35:37.5 |
HIP 30476 |
15.34 |
| 2026-06-06 00:00 |
06:24:35.85 |
-42:34:38.8 |
HIP 30476 |
16.45 |
| 2026-06-06 12:00 |
06:24:48.19 |
-42:33:41.2 |
HIP 30476 |
17.82 |
| 2026-06-07 00:00 |
06:25:00.54 |
-42:32:44.5 |
HIP 30476 |
19.39 |
| 2026-06-07 12:00 |
06:25:12.91 |
-42:31:48.9 |
HIP 30476 |
21.12 |
| 2026-06-08 00:00 |
06:25:25.31 |
-42:30:54.3 |
HIP 30476 |
22.97 |
| 2026-06-08 12:00 |
06:25:37.73 |
-42:30:00.7 |
HIP 30476 |
24.91 |
| 2026-06-09 00:00 |
06:25:50.16 |
-42:29:08.2 |
HIP 30476 |
26.92 |
| 2026-06-09 12:00 |
06:26:02.62 |
-42:28:16.6 |
HIP 30476 |
28.99 |
| 2026-06-10 00:00 |
06:26:15.09 |
-42:27:26.1 |
HIP 30476 |
31.11 |
| 2026-06-10 12:00 |
06:26:27.58 |
-42:26:36.7 |
HIP 30884 |
29.36 |
| 2026-06-11 00:00 |
06:26:40.09 |
-42:25:48.2 |
HIP 30884 |
26.92 |
| 2026-06-11 12:00 |
06:26:52.62 |
-42:25:00.8 |
HIP 30884 |
24.48 |
| 2026-06-12 00:00 |
06:27:05.16 |
-42:24:14.4 |
HIP 30884 |
22.04 |
| 2026-06-12 12:00 |
06:27:17.71 |
-42:23:29.0 |
HIP 30884 |
19.60 |
| 2026-06-13 00:00 |
06:27:30.28 |
-42:22:44.7 |
HIP 30884 |
17.16 |
| 2026-06-13 12:00 |
06:27:42.87 |
-42:22:01.4 |
HIP 30884 |
14.73 |
| 2026-06-14 00:00 |
06:27:55.47 |
-42:21:19.1 |
HIP 30884 |
12.30 |
| 2026-06-14 12:00 |
06:28:08.07 |
-42:20:37.9 |
HIP 30884 |
9.87 |
| 2026-06-15 00:00 |
06:28:20.70 |
-42:19:57.7 |
HIP 30884 |
7.45 |
| 2026-06-15 12:00 |
06:28:33.33 |
-42:19:18.5 |
HIP 30884 |
5.03 |
| 2026-06-16 00:00 |
06:28:45.97 |
-42:18:40.4 |
HIP 30884 |
2.63 |
| 2026-06-16 12:00 |
06:28:58.62 |
-42:18:03.3 |
HIP 30884 |
0.51 |
| 2026-06-17 00:00 |
06:29:11.28 |
-42:17:27.2 |
HIP 30884 |
2.31 |
| 2026-06-17 12:00 |
06:29:23.94 |
-42:16:52.2 |
HIP 30884 |
4.70 |
| 2026-06-18 00:00 |
06:29:36.62 |
-42:16:18.2 |
HIP 30962 |
3.86 |
| 2026-06-18 12:00 |
06:29:49.30 |
-42:15:45.3 |
HIP 30962 |
1.75 |
| 2026-06-19 00:00 |
06:30:01.98 |
-42:15:13.3 |
HIP 30962 |
1.68 |
| 2026-06-19 12:00 |
06:30:14.67 |
-42:14:42.4 |
HIP 30962 |
3.76 |
| 2026-06-20 00:00 |
06:30:27.37 |
-42:14:12.6 |
HIP 30962 |
6.07 |
| 2026-06-20 12:00 |
06:30:40.07 |
-42:13:43.7 |
HIP 30962 |
8.43 |
| 2026-06-21 00:00 |
06:30:52.77 |
-42:13:15.9 |
HIP 30962 |
10.80 |
| 2026-06-21 12:00 |
06:31:05.47 |
-42:12:49.2 |
HIP 30962 |
13.18 |
| 2026-06-22 00:00 |
06:31:18.17 |
-42:12:23.4 |
HIP 31189 |
15.06 |