C/1989 A6 (Shoemaker)
メタデータ
| 項目 |
値 |
| Designation |
C/1989 A6 (Shoemaker) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1988-11-02T02:05:44.491200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:38Z |
| Obs used |
28 |
| NEO |
- |
| M1 |
13.300 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1989-02-10.0000000 |
| e |
1.00000000 |
| q (au) |
2.207946 |
| a (au) |
- |
| i (deg) |
25.505596 |
| Ω (om, deg) |
74.314457 |
| ω (w, deg) |
18.838143 |
| M (ma, deg) |
- |
等級
散乱 + 全体線形
$$
M_a = (11.985 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.985 |
| n |
2.000 |
| gf |
1.000 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
16:44:17.08 |
-20:57:46.9 |
HIP 81887 |
18.44 |
| 2026-02-03 12:00 |
16:44:18.15 |
-20:57:48.7 |
HIP 81887 |
18.59 |
| 2026-02-04 00:00 |
16:44:19.20 |
-20:57:50.4 |
HIP 81887 |
18.74 |
| 2026-02-04 12:00 |
16:44:20.24 |
-20:57:52.1 |
HIP 81887 |
18.89 |
| 2026-02-05 00:00 |
16:44:21.26 |
-20:57:53.8 |
HIP 81887 |
19.05 |
| 2026-02-05 12:00 |
16:44:22.26 |
-20:57:55.5 |
HIP 81887 |
19.20 |
| 2026-02-06 00:00 |
16:44:23.25 |
-20:57:57.1 |
HIP 81887 |
19.34 |
| 2026-02-06 12:00 |
16:44:24.23 |
-20:57:58.7 |
HIP 81887 |
19.49 |
| 2026-02-07 00:00 |
16:44:25.18 |
-20:58:00.3 |
HIP 81887 |
19.64 |
| 2026-02-07 12:00 |
16:44:26.13 |
-20:58:01.8 |
HIP 81887 |
19.79 |
| 2026-02-08 00:00 |
16:44:27.05 |
-20:58:03.3 |
HIP 81887 |
19.93 |
| 2026-02-08 12:00 |
16:44:27.96 |
-20:58:04.8 |
HIP 81887 |
20.07 |
| 2026-02-09 00:00 |
16:44:28.85 |
-20:58:06.2 |
HIP 81887 |
20.21 |
| 2026-02-09 12:00 |
16:44:29.72 |
-20:58:07.6 |
HIP 81887 |
20.35 |
| 2026-02-10 00:00 |
16:44:30.58 |
-20:58:08.9 |
HIP 81887 |
20.49 |
| 2026-02-10 12:00 |
16:44:31.42 |
-20:58:10.3 |
HIP 81887 |
20.63 |
| 2026-02-11 00:00 |
16:44:32.25 |
-20:58:11.6 |
HIP 81887 |
20.77 |
| 2026-02-11 12:00 |
16:44:33.06 |
-20:58:12.8 |
HIP 81887 |
20.90 |
| 2026-02-12 00:00 |
16:44:33.85 |
-20:58:14.1 |
HIP 81887 |
21.03 |
| 2026-02-12 12:00 |
16:44:34.62 |
-20:58:15.3 |
HIP 81887 |
21.16 |
| 2026-02-13 00:00 |
16:44:35.38 |
-20:58:16.4 |
HIP 81887 |
21.28 |
| 2026-02-13 12:00 |
16:44:36.12 |
-20:58:17.6 |
HIP 81887 |
21.41 |
| 2026-02-14 00:00 |
16:44:36.84 |
-20:58:18.7 |
HIP 81887 |
21.53 |
| 2026-02-14 12:00 |
16:44:37.54 |
-20:58:19.7 |
HIP 81887 |
21.65 |
| 2026-02-15 00:00 |
16:44:38.23 |
-20:58:20.8 |
HIP 81887 |
21.77 |
| 2026-02-15 12:00 |
16:44:38.90 |
-20:58:21.7 |
HIP 81887 |
21.88 |
| 2026-02-16 00:00 |
16:44:39.55 |
-20:58:22.7 |
HIP 81887 |
21.99 |
| 2026-02-16 12:00 |
16:44:40.19 |
-20:58:23.6 |
HIP 81887 |
22.10 |
| 2026-02-17 00:00 |
16:44:40.81 |
-20:58:24.5 |
HIP 81887 |
22.21 |
| 2026-02-17 12:00 |
16:44:41.41 |
-20:58:25.4 |
HIP 81887 |
22.31 |
| 2026-02-18 00:00 |
16:44:41.99 |
-20:58:26.2 |
HIP 81887 |
22.42 |
| 2026-02-18 12:00 |
16:44:42.55 |
-20:58:27.0 |
HIP 81887 |
22.51 |
| 2026-02-19 00:00 |
16:44:43.10 |
-20:58:27.8 |
HIP 81887 |
22.61 |
| 2026-02-19 12:00 |
16:44:43.63 |
-20:58:28.5 |
HIP 81887 |
22.70 |
| 2026-02-20 00:00 |
16:44:44.14 |
-20:58:29.2 |
HIP 81887 |
22.79 |
| 2026-02-20 12:00 |
16:44:44.63 |
-20:58:29.9 |
HIP 81887 |
22.88 |
| 2026-02-21 00:00 |
16:44:45.11 |
-20:58:30.5 |
HIP 81887 |
22.96 |
| 2026-02-21 12:00 |
16:44:45.57 |
-20:58:31.1 |
HIP 81887 |
23.04 |
| 2026-02-22 00:00 |
16:44:46.01 |
-20:58:31.6 |
HIP 81887 |
23.12 |
| 2026-02-22 12:00 |
16:44:46.43 |
-20:58:32.2 |
HIP 81887 |
23.19 |
| 2026-02-23 00:00 |
16:44:46.83 |
-20:58:32.7 |
HIP 81887 |
23.27 |
| 2026-02-23 12:00 |
16:44:47.22 |
-20:58:33.1 |
HIP 81887 |
23.33 |
| 2026-02-24 00:00 |
16:44:47.59 |
-20:58:33.5 |
HIP 81887 |
23.40 |