メタデータ
| 項目 |
値 |
| Designation |
C/1989 A5 (Shoemaker) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1989-02-26T01:49:07.296960Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:38Z |
| Obs used |
77 |
| NEO |
- |
| M1 |
8.300 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1989-01-25.0000000 |
| e |
0.99551906 |
| q (au) |
2.639638 |
| a (au) |
589.081028 |
| i (deg) |
96.558535 |
| Ω (om, deg) |
137.139302 |
| ω (w, deg) |
19.104183 |
| M (ma, deg) |
359.997789 |
等級
散乱 + 全体線形
$$
M_a = (6.268 + 5.033\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.268 |
| n |
5.033 |
| gf |
1.000 |
| gb |
-0.872 |
| 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) |
| 2026-03-26 00:00 |
21:17:43.11 |
-11:01:33.0 |
HIP 105139 |
13.04 |
| 2026-03-26 12:00 |
21:17:44.42 |
-11:01:26.3 |
HIP 105139 |
12.86 |
| 2026-03-27 00:00 |
21:17:45.72 |
-11:01:19.7 |
HIP 105139 |
12.68 |
| 2026-03-27 12:00 |
21:17:47.01 |
-11:01:13.1 |
HIP 105139 |
12.52 |
| 2026-03-28 00:00 |
21:17:48.28 |
-11:01:06.5 |
HIP 105139 |
12.36 |
| 2026-03-28 12:00 |
21:17:49.54 |
-11:01:00.0 |
HIP 105139 |
12.20 |
| 2026-03-29 00:00 |
21:17:50.79 |
-11:00:53.5 |
HIP 105139 |
12.06 |
| 2026-03-29 12:00 |
21:17:52.03 |
-11:00:47.0 |
HIP 105139 |
11.92 |
| 2026-03-30 00:00 |
21:17:53.25 |
-11:00:40.6 |
HIP 105139 |
11.80 |
| 2026-03-30 12:00 |
21:17:54.47 |
-11:00:34.3 |
HIP 105139 |
11.68 |
| 2026-03-31 00:00 |
21:17:55.67 |
-11:00:28.0 |
HIP 105139 |
11.57 |
| 2026-03-31 12:00 |
21:17:56.85 |
-11:00:21.7 |
HIP 105139 |
11.46 |
| 2026-04-01 00:00 |
21:17:58.02 |
-11:00:15.5 |
HIP 105139 |
11.37 |
| 2026-04-01 12:00 |
21:17:59.18 |
-11:00:09.4 |
HIP 105139 |
11.28 |
| 2026-04-02 00:00 |
21:18:00.33 |
-11:00:03.2 |
HIP 105139 |
11.20 |
| 2026-04-02 12:00 |
21:18:01.46 |
-10:59:57.2 |
HIP 105139 |
11.13 |
| 2026-04-03 00:00 |
21:18:02.58 |
-10:59:51.2 |
HIP 105139 |
11.07 |
| 2026-04-03 12:00 |
21:18:03.69 |
-10:59:45.2 |
HIP 105139 |
11.01 |
| 2026-04-04 00:00 |
21:18:04.78 |
-10:59:39.3 |
HIP 105139 |
10.96 |
| 2026-04-04 12:00 |
21:18:05.86 |
-10:59:33.4 |
HIP 105139 |
10.92 |
| 2026-04-05 00:00 |
21:18:06.93 |
-10:59:27.6 |
HIP 105139 |
10.89 |
| 2026-04-05 12:00 |
21:18:07.98 |
-10:59:21.9 |
HIP 105139 |
10.86 |
| 2026-04-06 00:00 |
21:18:09.02 |
-10:59:16.2 |
HIP 105139 |
10.84 |
| 2026-04-06 12:00 |
21:18:10.04 |
-10:59:10.5 |
HIP 105139 |
10.83 |
| 2026-04-07 00:00 |
21:18:11.05 |
-10:59:04.9 |
HIP 105139 |
10.82 |
| 2026-04-07 12:00 |
21:18:12.05 |
-10:58:59.4 |
HIP 105139 |
10.82 |
| 2026-04-08 00:00 |
21:18:13.03 |
-10:58:53.9 |
HIP 105139 |
10.83 |
| 2026-04-08 12:00 |
21:18:14.00 |
-10:58:48.5 |
HIP 105139 |
10.84 |
| 2026-04-09 00:00 |
21:18:14.96 |
-10:58:43.1 |
HIP 105139 |
10.86 |
| 2026-04-09 12:00 |
21:18:15.90 |
-10:58:37.8 |
HIP 105139 |
10.88 |
| 2026-04-10 00:00 |
21:18:16.82 |
-10:58:32.5 |
HIP 105139 |
10.90 |
| 2026-04-10 12:00 |
21:18:17.73 |
-10:58:27.3 |
HIP 105139 |
10.93 |
| 2026-04-11 00:00 |
21:18:18.63 |
-10:58:22.1 |
HIP 105139 |
10.97 |
| 2026-04-11 12:00 |
21:18:19.51 |
-10:58:17.0 |
HIP 105139 |
11.01 |
| 2026-04-12 00:00 |
21:18:20.38 |
-10:58:12.0 |
HIP 105139 |
11.05 |
| 2026-04-12 12:00 |
21:18:21.23 |
-10:58:07.0 |
HIP 105139 |
11.09 |
| 2026-04-13 00:00 |
21:18:22.07 |
-10:58:02.1 |
HIP 105139 |
11.14 |
| 2026-04-13 12:00 |
21:18:22.90 |
-10:57:57.3 |
HIP 105139 |
11.19 |
| 2026-04-14 00:00 |
21:18:23.70 |
-10:57:52.5 |
HIP 105139 |
11.25 |
| 2026-04-14 12:00 |
21:18:24.50 |
-10:57:47.7 |
HIP 105139 |
11.30 |
| 2026-04-15 00:00 |
21:18:25.28 |
-10:57:43.1 |
HIP 105139 |
11.36 |
| 2026-04-15 12:00 |
21:18:26.04 |
-10:57:38.4 |
HIP 105139 |
11.42 |
| 2026-04-16 00:00 |
21:18:26.79 |
-10:57:33.9 |
HIP 105139 |
11.48 |