メタデータ
| 項目 |
値 |
| Designation |
C/2009 F6 (Yi-SWAN) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2009-05-07T10:24:24.171840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:30Z |
| Obs used |
487 |
| NEO |
- |
| M1 |
9.700 |
| K1 |
13.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2009-05-22.0000000 |
| e |
0.99751434 |
| q (au) |
1.274159 |
| a (au) |
512.604406 |
| i (deg) |
85.764786 |
| Ω (om, deg) |
278.679026 |
| ω (w, deg) |
129.772327 |
| M (ma, deg) |
0.001237 |
等級
散乱 + 全体線形
$$
M_a = (9.977 + 4.261\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
9.977 |
| n |
4.261 |
| gf |
1.000 |
| gb |
-0.998 |
| k |
1.000 |
| 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) |
| 2026-09-20 00:00 |
08:07:41.09 |
-84:39:31.8 |
HIP 39998 |
13.29 |
| 2026-09-20 12:00 |
08:07:59.59 |
-84:40:12.6 |
HIP 39998 |
13.85 |
| 2026-09-21 00:00 |
08:08:17.91 |
-84:40:53.6 |
HIP 39998 |
14.43 |
| 2026-09-21 12:00 |
08:08:36.07 |
-84:41:34.8 |
HIP 39998 |
15.04 |
| 2026-09-22 00:00 |
08:08:54.04 |
-84:42:16.2 |
HIP 39998 |
15.67 |
| 2026-09-22 12:00 |
08:09:11.84 |
-84:42:57.8 |
HIP 39998 |
16.32 |
| 2026-09-23 00:00 |
08:09:29.45 |
-84:43:39.6 |
HIP 39998 |
16.99 |
| 2026-09-23 12:00 |
08:09:46.88 |
-84:44:21.5 |
HIP 39998 |
17.67 |
| 2026-09-24 00:00 |
08:10:04.13 |
-84:45:03.6 |
HIP 39998 |
18.36 |
| 2026-09-24 12:00 |
08:10:21.20 |
-84:45:46.0 |
HIP 39998 |
19.07 |
| 2026-09-25 00:00 |
08:10:38.07 |
-84:46:28.4 |
HIP 39998 |
19.79 |
| 2026-09-25 12:00 |
08:10:54.76 |
-84:47:11.1 |
HIP 40701 |
20.09 |
| 2026-09-26 00:00 |
08:11:11.25 |
-84:47:53.9 |
HIP 40701 |
19.29 |
| 2026-09-26 12:00 |
08:11:27.55 |
-84:48:36.9 |
HIP 40701 |
18.48 |
| 2026-09-27 00:00 |
08:11:43.65 |
-84:49:20.1 |
HIP 40701 |
17.68 |
| 2026-09-27 12:00 |
08:11:59.56 |
-84:50:03.4 |
HIP 40701 |
16.87 |
| 2026-09-28 00:00 |
08:12:15.27 |
-84:50:46.9 |
HIP 40701 |
16.07 |
| 2026-09-28 12:00 |
08:12:30.78 |
-84:51:30.6 |
HIP 40701 |
15.26 |
| 2026-09-29 00:00 |
08:12:46.08 |
-84:52:14.4 |
HIP 40701 |
14.46 |
| 2026-09-29 12:00 |
08:13:01.18 |
-84:52:58.4 |
HIP 40701 |
13.66 |
| 2026-09-30 00:00 |
08:13:16.07 |
-84:53:42.6 |
HIP 40701 |
12.86 |
| 2026-09-30 12:00 |
08:13:30.75 |
-84:54:26.9 |
HIP 40701 |
12.06 |
| 2026-10-01 00:00 |
08:13:45.22 |
-84:55:11.4 |
HIP 40701 |
11.26 |
| 2026-10-01 12:00 |
08:13:59.47 |
-84:55:56.0 |
HIP 40701 |
10.47 |
| 2026-10-02 00:00 |
08:14:13.51 |
-84:56:40.8 |
HIP 40701 |
9.67 |
| 2026-10-02 12:00 |
08:14:27.33 |
-84:57:25.7 |
HIP 40701 |
8.89 |
| 2026-10-03 00:00 |
08:14:40.93 |
-84:58:10.8 |
HIP 40701 |
8.11 |
| 2026-10-03 12:00 |
08:14:54.30 |
-84:58:56.0 |
HIP 40701 |
7.33 |
| 2026-10-04 00:00 |
08:15:07.45 |
-84:59:41.4 |
HIP 40701 |
6.57 |
| 2026-10-04 12:00 |
08:15:20.37 |
-85:00:26.9 |
HIP 40701 |
5.82 |
| 2026-10-05 00:00 |
08:15:33.05 |
-85:01:12.5 |
HIP 40701 |
5.10 |
| 2026-10-05 12:00 |
08:15:45.50 |
-85:01:58.3 |
HIP 40701 |
4.40 |
| 2026-10-06 00:00 |
08:15:57.72 |
-85:02:44.2 |
HIP 40701 |
3.76 |
| 2026-10-06 12:00 |
08:16:09.69 |
-85:03:30.3 |
HIP 40701 |
3.20 |
| 2026-10-07 00:00 |
08:16:21.43 |
-85:04:16.5 |
HIP 40701 |
2.78 |
| 2026-10-07 12:00 |
08:16:32.91 |
-85:05:02.8 |
HIP 40701 |
2.55 |
| 2026-10-08 00:00 |
08:16:44.15 |
-85:05:49.3 |
HIP 40701 |
2.58 |
| 2026-10-08 12:00 |
08:16:55.14 |
-85:06:35.8 |
HIP 40701 |
2.86 |
| 2026-10-09 00:00 |
08:17:05.88 |
-85:07:22.5 |
HIP 40701 |
3.32 |
| 2026-10-09 12:00 |
08:17:16.36 |
-85:08:09.3 |
HIP 40701 |
3.90 |
| 2026-10-10 00:00 |
08:17:26.59 |
-85:08:56.3 |
HIP 40701 |
4.56 |
| 2026-10-10 12:00 |
08:17:36.55 |
-85:09:43.3 |
HIP 40701 |
5.26 |
| 2026-10-11 00:00 |
08:17:46.25 |
-85:10:30.5 |
HIP 40701 |
5.99 |