メタデータ
| 項目 |
値 |
| Designation |
257P/Catalina |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-06-04T09:54:55.097280Z |
| Orbit solution date (soln_date, UTC) |
2023-01-14T00:13:33Z |
| Obs used |
2118 |
| NEO |
- |
| M1 |
15.100 |
| K1 |
5.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-12-24.0000000 |
| e |
0.43237437 |
| q (au) |
2.130596 |
| a (au) |
3.753523 |
| i (deg) |
20.240315 |
| Ω (om, deg) |
207.850144 |
| ω (w, deg) |
117.883991 |
| M (ma, deg) |
76.926834 |
等級
散乱 + 全体線形
$$
M_a = (13.517 + 2.899\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.517 |
| n |
2.899 |
| gf |
0.999 |
| gb |
-0.502 |
| 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
ファインディングチャート
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
12:43:39.60 |
-05:21:36.6 |
HIP 62013 |
17.13 |
| 2026-07-29 12:00 |
12:44:01.21 |
-05:22:38.2 |
HIP 62013 |
21.92 |
| 2026-07-30 00:00 |
12:44:22.97 |
-05:23:40.9 |
HIP 62250 |
22.54 |
| 2026-07-30 12:00 |
12:44:44.87 |
-05:24:44.6 |
HIP 62250 |
20.02 |
| 2026-07-31 00:00 |
12:45:06.91 |
-05:25:49.4 |
HIP 62250 |
18.86 |
| 2026-07-31 12:00 |
12:45:29.10 |
-05:26:55.1 |
HIP 62250 |
19.34 |
| 2026-08-01 00:00 |
12:45:51.42 |
-05:28:01.9 |
HIP 62250 |
21.37 |
| 2026-08-01 12:00 |
12:46:13.88 |
-05:29:09.7 |
HIP 62250 |
24.60 |
| 2026-08-02 00:00 |
12:46:36.48 |
-05:30:18.5 |
HIP 62419 |
26.94 |
| 2026-08-02 12:00 |
12:46:59.21 |
-05:31:28.3 |
HIP 62419 |
23.43 |
| 2026-08-03 00:00 |
12:47:22.09 |
-05:32:39.1 |
HIP 62419 |
20.94 |
| 2026-08-03 12:00 |
12:47:45.10 |
-05:33:50.8 |
HIP 62419 |
19.87 |
| 2026-08-04 00:00 |
12:48:08.24 |
-05:35:03.5 |
HIP 62565 |
17.31 |
| 2026-08-04 12:00 |
12:48:31.52 |
-05:36:17.2 |
HIP 62565 |
13.40 |
| 2026-08-05 00:00 |
12:48:54.94 |
-05:37:31.8 |
HIP 62565 |
11.40 |
| 2026-08-05 12:00 |
12:49:18.49 |
-05:38:47.4 |
HIP 62565 |
12.32 |
| 2026-08-06 00:00 |
12:49:42.17 |
-05:40:03.9 |
HIP 62565 |
15.70 |
| 2026-08-06 12:00 |
12:50:05.99 |
-05:41:21.4 |
HIP 62565 |
20.37 |
| 2026-08-07 00:00 |
12:50:29.94 |
-05:42:39.8 |
HIP 62701 |
21.92 |
| 2026-08-07 12:00 |
12:50:54.02 |
-05:43:59.1 |
HIP 62701 |
19.67 |
| 2026-08-08 00:00 |
12:51:18.23 |
-05:45:19.3 |
HIP 62701 |
19.20 |
| 2026-08-08 12:00 |
12:51:42.57 |
-05:46:40.5 |
HIP 62810 |
20.17 |
| 2026-08-09 00:00 |
12:52:07.04 |
-05:48:02.5 |
HIP 62810 |
17.42 |
| 2026-08-09 12:00 |
12:52:31.64 |
-05:49:25.4 |
HIP 62810 |
16.67 |
| 2026-08-10 00:00 |
12:52:56.37 |
-05:50:49.2 |
HIP 62810 |
18.19 |
| 2026-08-10 12:00 |
12:53:21.22 |
-05:52:13.9 |
HIP 62810 |
21.55 |
| 2026-08-11 00:00 |
12:53:46.21 |
-05:53:39.5 |
HIP 62810 |
26.06 |
| 2026-08-11 12:00 |
12:54:11.31 |
-05:55:05.9 |
HIP 63023 |
27.55 |
| 2026-08-12 00:00 |
12:54:36.55 |
-05:56:33.1 |
HIP 63023 |
24.24 |
| 2026-08-12 12:00 |
12:55:01.91 |
-05:58:01.2 |
HIP 63023 |
22.32 |
| 2026-08-13 00:00 |
12:55:27.39 |
-05:59:30.1 |
HIP 63023 |
22.19 |
| 2026-08-13 12:00 |
12:55:53.00 |
-06:00:59.9 |
HIP 63161 |
20.86 |
| 2026-08-14 00:00 |
12:56:18.73 |
-06:02:30.5 |
HIP 63161 |
17.37 |
| 2026-08-14 12:00 |
12:56:44.58 |
-06:04:01.8 |
HIP 63161 |
15.96 |
| 2026-08-15 00:00 |
12:57:10.55 |
-06:05:34.0 |
HIP 63161 |
17.18 |
| 2026-08-15 12:00 |
12:57:36.65 |
-06:07:07.0 |
HIP 63161 |
20.59 |
| 2026-08-16 00:00 |
12:58:02.86 |
-06:08:40.7 |
HIP 63363 |
14.61 |
| 2026-08-16 12:00 |
12:58:29.19 |
-06:10:15.2 |
HIP 63363 |
9.08 |
| 2026-08-17 00:00 |
12:58:55.64 |
-06:11:50.5 |
HIP 63363 |
6.49 |
| 2026-08-17 12:00 |
12:59:22.20 |
-06:13:26.5 |
HIP 63363 |
9.68 |
| 2026-08-18 00:00 |
12:59:48.88 |
-06:15:03.3 |
HIP 63363 |
15.45 |
| 2026-08-18 12:00 |
13:00:15.68 |
-06:16:40.7 |
HIP 63363 |
21.87 |
| 2026-08-19 00:00 |
13:00:42.59 |
-06:18:19.0 |
HIP 63363 |
28.52 |