メタデータ
| 項目 |
値 |
| Designation |
293P/Spacewatch |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-01-10T06:55:08.644800Z |
| Orbit solution date (soln_date, UTC) |
2022-06-12T21:06:40Z |
| Obs used |
463 |
| NEO |
- |
| M1 |
15.800 |
| K1 |
7.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-01-02.0000000 |
| e |
0.41974111 |
| q (au) |
2.111752 |
| a (au) |
3.639328 |
| i (deg) |
9.064844 |
| Ω (om, deg) |
78.437790 |
| ω (w, deg) |
41.152848 |
| M (ma, deg) |
358.823377 |
等級
散乱 + 全体線形
$$
M_a = (15.488 + 2.988\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.488 |
| n |
2.988 |
| gf |
0.999 |
| gb |
-0.716 |
| k |
0.994 |
| 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) |
| 2026-03-26 00:00 |
23:39:11.76 |
-10:16:19.1 |
HIP 116719 |
17.26 |
| 2026-03-26 12:00 |
23:39:42.26 |
-10:13:11.0 |
HIP 116811 |
11.48 |
| 2026-03-27 00:00 |
23:40:12.75 |
-10:10:03.1 |
HIP 116811 |
5.37 |
| 2026-03-27 12:00 |
23:40:43.24 |
-10:06:55.5 |
HIP 116811 |
7.61 |
| 2026-03-28 00:00 |
23:41:13.71 |
-10:03:48.0 |
HIP 116811 |
14.80 |
| 2026-03-28 12:00 |
23:41:44.18 |
-10:00:40.8 |
HIP 116811 |
22.63 |
| 2026-03-29 00:00 |
23:42:14.64 |
-09:57:33.8 |
HIP 117044 |
26.46 |
| 2026-03-29 12:00 |
23:42:45.09 |
-09:54:27.1 |
HIP 117044 |
18.89 |
| 2026-03-30 00:00 |
23:43:15.53 |
-09:51:20.5 |
HIP 117044 |
12.07 |
| 2026-03-30 12:00 |
23:43:45.97 |
-09:48:14.3 |
HIP 117044 |
8.14 |
| 2026-03-31 00:00 |
23:44:16.39 |
-09:45:08.2 |
HIP 117044 |
10.89 |
| 2026-03-31 12:00 |
23:44:46.80 |
-09:42:02.4 |
HIP 117044 |
17.39 |
| 2026-04-01 00:00 |
23:45:17.20 |
-09:38:56.9 |
HIP 117044 |
24.86 |
| 2026-04-01 12:00 |
23:45:47.60 |
-09:35:51.6 |
HIP 117318 |
25.96 |
| 2026-04-02 00:00 |
23:46:17.98 |
-09:32:46.6 |
HIP 117318 |
21.87 |
| 2026-04-02 12:00 |
23:46:48.34 |
-09:29:41.8 |
HIP 117318 |
20.34 |
| 2026-04-03 00:00 |
23:47:18.70 |
-09:26:37.4 |
HIP 117318 |
21.90 |
| 2026-04-03 12:00 |
23:47:49.04 |
-09:23:33.1 |
HIP 117318 |
26.01 |
| 2026-04-04 00:00 |
23:48:19.37 |
-09:20:29.2 |
HIP 117533 |
30.34 |
| 2026-04-04 12:00 |
23:48:49.69 |
-09:17:25.5 |
HIP 117533 |
25.64 |
| 2026-04-05 00:00 |
23:49:19.99 |
-09:14:22.1 |
HIP 117533 |
22.90 |
| 2026-04-05 12:00 |
23:49:50.28 |
-09:11:19.0 |
HIP 117533 |
22.84 |
| 2026-04-06 00:00 |
23:50:20.56 |
-09:08:16.2 |
HIP 117533 |
25.47 |
| 2026-04-06 12:00 |
23:50:50.81 |
-09:05:13.7 |
HIP 117756 |
30.04 |
| 2026-04-07 00:00 |
23:51:21.06 |
-09:02:11.5 |
HIP 117756 |
22.21 |
| 2026-04-07 12:00 |
23:51:51.29 |
-08:59:09.6 |
HIP 117743 |
14.31 |
| 2026-04-08 00:00 |
23:52:21.50 |
-08:56:08.1 |
HIP 117743 |
6.26 |
| 2026-04-08 12:00 |
23:52:51.69 |
-08:53:06.8 |
HIP 117743 |
1.79 |
| 2026-04-09 00:00 |
23:53:21.87 |
-08:50:05.9 |
HIP 117743 |
9.83 |
| 2026-04-09 12:00 |
23:53:52.03 |
-08:47:05.2 |
HIP 117743 |
17.86 |
| 2026-04-10 00:00 |
23:54:22.17 |
-08:44:04.9 |
HIP 117924 |
20.79 |
| 2026-04-10 12:00 |
23:54:52.29 |
-08:41:05.0 |
HIP 117924 |
15.04 |
| 2026-04-11 00:00 |
23:55:22.39 |
-08:38:05.4 |
HIP 117924 |
12.21 |
| 2026-04-11 12:00 |
23:55:52.47 |
-08:35:06.1 |
HIP 117924 |
14.17 |
| 2026-04-12 00:00 |
23:56:22.54 |
-08:32:07.2 |
HIP 117924 |
19.51 |
| 2026-04-12 12:00 |
23:56:52.58 |
-08:29:08.7 |
HIP 117924 |
26.24 |
| 2026-04-13 00:00 |
23:57:22.60 |
-08:26:10.5 |
HIP 118253 |
26.23 |
| 2026-04-13 12:00 |
23:57:52.59 |
-08:23:12.7 |
HIP 118253 |
19.58 |
| 2026-04-14 00:00 |
23:58:22.57 |
-08:20:15.2 |
HIP 118253 |
14.38 |
| 2026-04-14 12:00 |
23:58:52.52 |
-08:17:18.2 |
HIP 118253 |
12.55 |
| 2026-04-15 00:00 |
23:59:22.45 |
-08:14:21.5 |
HIP 118253 |
15.33 |
| 2026-04-15 12:00 |
23:59:52.35 |
-08:11:25.2 |
HIP 118253 |
20.95 |
| 2026-04-16 00:00 |
00:00:22.23 |
-08:08:29.3 |
HIP 118294 |
23.03 |