メタデータ
| 項目 |
値 |
| Designation |
C/1965 S2 (Alcock) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1965-10-26T03:16:48.961920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:17Z |
| Obs used |
29 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1965-10-11.0000000 |
| e |
1.00034477 |
| q (au) |
1.293959 |
| a (au) |
-3753.106898 |
| i (deg) |
65.010799 |
| Ω (om, deg) |
175.619427 |
| ω (w, deg) |
150.520426 |
| M (ma, deg) |
-0.000065 |
等級
散乱 + 全体線形
$$
M_a = (9.066 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
9.066 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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) |
| 2026-09-20 00:00 |
09:25:49.35 |
-25:33:29.6 |
HIP 46238 |
13.55 |
| 2026-09-20 12:00 |
09:25:50.49 |
-25:33:41.5 |
HIP 46238 |
13.80 |
| 2026-09-21 00:00 |
09:25:51.63 |
-25:33:53.5 |
HIP 46238 |
14.06 |
| 2026-09-21 12:00 |
09:25:52.76 |
-25:34:05.6 |
HIP 46238 |
14.31 |
| 2026-09-22 00:00 |
09:25:53.88 |
-25:34:17.8 |
HIP 46238 |
14.57 |
| 2026-09-22 12:00 |
09:25:54.99 |
-25:34:29.9 |
HIP 46238 |
14.84 |
| 2026-09-23 00:00 |
09:25:56.10 |
-25:34:42.2 |
HIP 46238 |
15.10 |
| 2026-09-23 12:00 |
09:25:57.20 |
-25:34:54.5 |
HIP 46238 |
15.37 |
| 2026-09-24 00:00 |
09:25:58.29 |
-25:35:06.9 |
HIP 46238 |
15.64 |
| 2026-09-24 12:00 |
09:25:59.37 |
-25:35:19.3 |
HIP 46238 |
15.91 |
| 2026-09-25 00:00 |
09:26:00.44 |
-25:35:31.8 |
HIP 46238 |
16.19 |
| 2026-09-25 12:00 |
09:26:01.51 |
-25:35:44.3 |
HIP 46238 |
16.46 |
| 2026-09-26 00:00 |
09:26:02.56 |
-25:35:56.9 |
HIP 46238 |
16.74 |
| 2026-09-26 12:00 |
09:26:03.61 |
-25:36:09.6 |
HIP 46238 |
17.02 |
| 2026-09-27 00:00 |
09:26:04.65 |
-25:36:22.3 |
HIP 46238 |
17.30 |
| 2026-09-27 12:00 |
09:26:05.68 |
-25:36:35.0 |
HIP 46238 |
17.59 |
| 2026-09-28 00:00 |
09:26:06.71 |
-25:36:47.9 |
HIP 46238 |
17.87 |
| 2026-09-28 12:00 |
09:26:07.72 |
-25:37:00.7 |
HIP 46238 |
18.16 |
| 2026-09-29 00:00 |
09:26:08.73 |
-25:37:13.6 |
HIP 46238 |
18.44 |
| 2026-09-29 12:00 |
09:26:09.72 |
-25:37:26.6 |
HIP 46238 |
18.73 |
| 2026-09-30 00:00 |
09:26:10.71 |
-25:37:39.6 |
HIP 46238 |
19.02 |
| 2026-09-30 12:00 |
09:26:11.69 |
-25:37:52.7 |
HIP 46238 |
19.30 |
| 2026-10-01 00:00 |
09:26:12.66 |
-25:38:05.8 |
HIP 46238 |
19.59 |
| 2026-10-01 12:00 |
09:26:13.62 |
-25:38:18.9 |
HIP 46238 |
19.88 |
| 2026-10-02 00:00 |
09:26:14.57 |
-25:38:32.1 |
HIP 46238 |
20.17 |
| 2026-10-02 12:00 |
09:26:15.52 |
-25:38:45.4 |
HIP 46238 |
20.46 |
| 2026-10-03 00:00 |
09:26:16.45 |
-25:38:58.6 |
HIP 46238 |
20.75 |
| 2026-10-03 12:00 |
09:26:17.37 |
-25:39:12.0 |
HIP 46238 |
21.04 |
| 2026-10-04 00:00 |
09:26:18.29 |
-25:39:25.3 |
HIP 46238 |
21.33 |
| 2026-10-04 12:00 |
09:26:19.19 |
-25:39:38.8 |
HIP 46238 |
21.62 |
| 2026-10-05 00:00 |
09:26:20.09 |
-25:39:52.2 |
HIP 46238 |
21.91 |
| 2026-10-05 12:00 |
09:26:20.97 |
-25:40:05.7 |
HIP 46238 |
22.20 |
| 2026-10-06 00:00 |
09:26:21.85 |
-25:40:19.2 |
HIP 46238 |
22.49 |
| 2026-10-06 12:00 |
09:26:22.71 |
-25:40:32.8 |
HIP 46238 |
22.78 |
| 2026-10-07 00:00 |
09:26:23.57 |
-25:40:46.4 |
HIP 46238 |
23.07 |
| 2026-10-07 12:00 |
09:26:24.42 |
-25:41:00.0 |
HIP 46238 |
23.36 |
| 2026-10-08 00:00 |
09:26:25.25 |
-25:41:13.7 |
HIP 46238 |
23.65 |
| 2026-10-08 12:00 |
09:26:26.08 |
-25:41:27.4 |
HIP 46238 |
23.94 |
| 2026-10-09 00:00 |
09:26:26.89 |
-25:41:41.1 |
HIP 46238 |
24.22 |
| 2026-10-09 12:00 |
09:26:27.70 |
-25:41:54.9 |
HIP 46238 |
24.51 |
| 2026-10-10 00:00 |
09:26:28.49 |
-25:42:08.7 |
HIP 46238 |
24.80 |
| 2026-10-10 12:00 |
09:26:29.28 |
-25:42:22.5 |
HIP 46238 |
25.09 |
| 2026-10-11 00:00 |
09:26:30.05 |
-25:42:36.4 |
HIP 46238 |
25.37 |