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) |
| 2026-07-29 00:00 |
09:23:23.95 |
-25:20:45.1 |
HIP 46238 |
30.08 |
| 2026-07-29 12:00 |
09:23:25.36 |
-25:20:46.8 |
HIP 46238 |
29.76 |
| 2026-07-30 00:00 |
09:23:26.78 |
-25:20:48.5 |
HIP 46238 |
29.44 |
| 2026-07-30 12:00 |
09:23:28.21 |
-25:20:50.4 |
HIP 46238 |
29.12 |
| 2026-07-31 00:00 |
09:23:29.63 |
-25:20:52.4 |
HIP 46238 |
28.80 |
| 2026-07-31 12:00 |
09:23:31.06 |
-25:20:54.5 |
HIP 46238 |
28.48 |
| 2026-08-01 00:00 |
09:23:32.49 |
-25:20:56.7 |
HIP 46238 |
28.16 |
| 2026-08-01 12:00 |
09:23:33.92 |
-25:20:59.1 |
HIP 46238 |
27.84 |
| 2026-08-02 00:00 |
09:23:35.35 |
-25:21:01.5 |
HIP 46238 |
27.51 |
| 2026-08-02 12:00 |
09:23:36.78 |
-25:21:04.1 |
HIP 46238 |
27.19 |
| 2026-08-03 00:00 |
09:23:38.22 |
-25:21:06.8 |
HIP 46238 |
26.87 |
| 2026-08-03 12:00 |
09:23:39.66 |
-25:21:09.6 |
HIP 46238 |
26.54 |
| 2026-08-04 00:00 |
09:23:41.10 |
-25:21:12.5 |
HIP 46238 |
26.22 |
| 2026-08-04 12:00 |
09:23:42.54 |
-25:21:15.5 |
HIP 46238 |
25.90 |
| 2026-08-05 00:00 |
09:23:43.98 |
-25:21:18.7 |
HIP 46238 |
25.57 |
| 2026-08-05 12:00 |
09:23:45.43 |
-25:21:22.0 |
HIP 46238 |
25.25 |
| 2026-08-06 00:00 |
09:23:46.87 |
-25:21:25.3 |
HIP 46238 |
24.93 |
| 2026-08-06 12:00 |
09:23:48.32 |
-25:21:28.8 |
HIP 46238 |
24.60 |
| 2026-08-07 00:00 |
09:23:49.76 |
-25:21:32.4 |
HIP 46238 |
24.28 |
| 2026-08-07 12:00 |
09:23:51.21 |
-25:21:36.2 |
HIP 46238 |
23.96 |
| 2026-08-08 00:00 |
09:23:52.66 |
-25:21:40.0 |
HIP 46238 |
23.63 |
| 2026-08-08 12:00 |
09:23:54.11 |
-25:21:43.9 |
HIP 46238 |
23.31 |
| 2026-08-09 00:00 |
09:23:55.56 |
-25:21:48.0 |
HIP 46238 |
22.99 |
| 2026-08-09 12:00 |
09:23:57.01 |
-25:21:52.2 |
HIP 46238 |
22.67 |
| 2026-08-10 00:00 |
09:23:58.46 |
-25:21:56.5 |
HIP 46238 |
22.35 |
| 2026-08-10 12:00 |
09:23:59.91 |
-25:22:00.9 |
HIP 46238 |
22.02 |
| 2026-08-11 00:00 |
09:24:01.36 |
-25:22:05.4 |
HIP 46238 |
21.70 |
| 2026-08-11 12:00 |
09:24:02.82 |
-25:22:10.0 |
HIP 46238 |
21.38 |
| 2026-08-12 00:00 |
09:24:04.27 |
-25:22:14.8 |
HIP 46238 |
21.06 |
| 2026-08-12 12:00 |
09:24:05.72 |
-25:22:19.6 |
HIP 46238 |
20.75 |
| 2026-08-13 00:00 |
09:24:07.17 |
-25:22:24.6 |
HIP 46238 |
20.43 |
| 2026-08-13 12:00 |
09:24:08.62 |
-25:22:29.6 |
HIP 46238 |
20.11 |
| 2026-08-14 00:00 |
09:24:10.07 |
-25:22:34.8 |
HIP 46238 |
19.80 |
| 2026-08-14 12:00 |
09:24:11.52 |
-25:22:40.1 |
HIP 46238 |
19.48 |
| 2026-08-15 00:00 |
09:24:12.97 |
-25:22:45.5 |
HIP 46238 |
19.17 |
| 2026-08-15 12:00 |
09:24:14.42 |
-25:22:51.0 |
HIP 46238 |
18.86 |
| 2026-08-16 00:00 |
09:24:15.86 |
-25:22:56.7 |
HIP 46238 |
18.55 |
| 2026-08-16 12:00 |
09:24:17.31 |
-25:23:02.4 |
HIP 46238 |
18.24 |
| 2026-08-17 00:00 |
09:24:18.76 |
-25:23:08.2 |
HIP 46238 |
17.93 |
| 2026-08-17 12:00 |
09:24:20.20 |
-25:23:14.2 |
HIP 46238 |
17.63 |
| 2026-08-18 00:00 |
09:24:21.64 |
-25:23:20.2 |
HIP 46238 |
17.32 |
| 2026-08-18 12:00 |
09:24:23.08 |
-25:23:26.4 |
HIP 46238 |
17.02 |
| 2026-08-19 00:00 |
09:24:24.52 |
-25:23:32.6 |
HIP 46238 |
16.72 |