メタデータ
| 項目 |
値 |
| Designation |
P/2013 YG46 (Spacewatch) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-01-19T12:53:16.437120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:44Z |
| Obs used |
55 |
| NEO |
- |
| M1 |
10.600 |
| K1 |
10.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-01-29.0000000 |
| e |
0.45164645 |
| q (au) |
1.815243 |
| a (au) |
3.310351 |
| i (deg) |
8.219141 |
| Ω (om, deg) |
56.868085 |
| ω (w, deg) |
232.796581 |
| M (ma, deg) |
182.197613 |
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) |
| 2026-09-20 00:00 |
09:27:26.12 |
+21:22:01.9 |
HIP 46309 |
13.85 |
| 2026-09-20 12:00 |
09:27:51.67 |
+21:20:23.9 |
HIP 46309 |
19.78 |
| 2026-09-21 00:00 |
09:28:17.14 |
+21:18:46.1 |
HIP 46309 |
25.80 |
| 2026-09-21 12:00 |
09:28:42.54 |
+21:17:08.7 |
HIP 46527 |
24.16 |
| 2026-09-22 00:00 |
09:29:07.88 |
+21:15:31.7 |
HIP 46527 |
20.93 |
| 2026-09-22 12:00 |
09:29:33.14 |
+21:13:55.0 |
HIP 46527 |
19.18 |
| 2026-09-23 00:00 |
09:29:58.32 |
+21:12:18.6 |
HIP 46527 |
19.29 |
| 2026-09-23 12:00 |
09:30:23.44 |
+21:10:42.6 |
HIP 46527 |
21.23 |
| 2026-09-24 00:00 |
09:30:48.48 |
+21:09:06.9 |
HIP 46527 |
24.54 |
| 2026-09-24 12:00 |
09:31:13.44 |
+21:07:31.6 |
HIP 46828 |
28.29 |
| 2026-09-25 00:00 |
09:31:38.33 |
+21:05:56.6 |
HIP 46828 |
23.51 |
| 2026-09-25 12:00 |
09:32:03.14 |
+21:04:22.1 |
HIP 46828 |
19.44 |
| 2026-09-26 00:00 |
09:32:27.88 |
+21:02:47.9 |
HIP 46828 |
16.60 |
| 2026-09-26 12:00 |
09:32:52.53 |
+21:01:14.1 |
HIP 46828 |
15.65 |
| 2026-09-27 00:00 |
09:33:17.11 |
+20:59:40.7 |
HIP 46828 |
16.89 |
| 2026-09-27 12:00 |
09:33:41.61 |
+20:58:07.7 |
HIP 46828 |
19.90 |
| 2026-09-28 00:00 |
09:34:06.03 |
+20:56:35.1 |
HIP 46828 |
24.01 |
| 2026-09-28 12:00 |
09:34:30.38 |
+20:55:02.9 |
HIP 46828 |
28.74 |
| 2026-09-29 00:00 |
09:34:54.63 |
+20:53:31.1 |
HIP 46828 |
33.82 |
| 2026-09-29 12:00 |
09:35:18.81 |
+20:51:59.7 |
HIP 46828 |
39.11 |
| 2026-09-30 00:00 |
09:35:42.91 |
+20:50:28.8 |
HIP 46828 |
44.52 |
| 2026-09-30 12:00 |
09:36:06.92 |
+20:48:58.3 |
HIP 47104 |
46.25 |
| 2026-10-01 00:00 |
09:36:30.85 |
+20:47:28.2 |
HIP 47377 |
42.07 |
| 2026-10-01 12:00 |
09:36:54.69 |
+20:45:58.6 |
HIP 47377 |
36.47 |
| 2026-10-02 00:00 |
09:37:18.44 |
+20:44:29.4 |
HIP 47377 |
30.96 |
| 2026-10-02 12:00 |
09:37:42.11 |
+20:43:00.7 |
HIP 47377 |
25.57 |
| 2026-10-03 00:00 |
09:38:05.70 |
+20:41:32.5 |
HIP 47377 |
20.40 |
| 2026-10-03 12:00 |
09:38:29.19 |
+20:40:04.8 |
HIP 47377 |
15.62 |
| 2026-10-04 00:00 |
09:38:52.59 |
+20:38:37.5 |
HIP 47377 |
11.70 |
| 2026-10-04 12:00 |
09:39:15.91 |
+20:37:10.7 |
HIP 47377 |
9.71 |
| 2026-10-05 00:00 |
09:39:39.13 |
+20:35:44.4 |
HIP 47377 |
10.73 |
| 2026-10-05 12:00 |
09:40:02.26 |
+20:34:18.6 |
HIP 47377 |
14.10 |
| 2026-10-06 00:00 |
09:40:25.29 |
+20:32:53.4 |
HIP 47377 |
18.57 |
| 2026-10-06 12:00 |
09:40:48.24 |
+20:31:28.6 |
HIP 47377 |
23.49 |
| 2026-10-07 00:00 |
09:41:11.08 |
+20:30:04.4 |
HIP 47377 |
28.63 |
| 2026-10-07 12:00 |
09:41:33.83 |
+20:28:40.7 |
HIP 47684 |
30.67 |
| 2026-10-08 00:00 |
09:41:56.48 |
+20:27:17.6 |
HIP 47684 |
25.55 |
| 2026-10-08 12:00 |
09:42:19.04 |
+20:25:55.0 |
HIP 47684 |
20.65 |
| 2026-10-09 00:00 |
09:42:41.49 |
+20:24:33.0 |
HIP 47684 |
16.13 |
| 2026-10-09 12:00 |
09:43:03.85 |
+20:23:11.6 |
HIP 47684 |
12.39 |
| 2026-10-10 00:00 |
09:43:26.10 |
+20:21:50.7 |
HIP 47684 |
10.29 |
| 2026-10-10 12:00 |
09:43:48.25 |
+20:20:30.4 |
HIP 47684 |
10.77 |
| 2026-10-11 00:00 |
09:44:10.30 |
+20:19:10.7 |
HIP 47684 |
13.54 |