メタデータ
| 項目 |
値 |
| Designation |
C/1992 A1 (Helin-Alu) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1992-07-08T17:12:35.945280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:41Z |
| Obs used |
53 |
| NEO |
- |
| M1 |
12.200 |
| K1 |
4.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1992-02-26.0000000 |
| e |
1.00425169 |
| q (au) |
3.016597 |
| a (au) |
-709.504993 |
| i (deg) |
39.271080 |
| Ω (om, deg) |
288.912404 |
| ω (w, deg) |
239.843091 |
| M (ma, deg) |
-0.006974 |
等級
散乱 + 全体線形
$$
M_a = (5.138 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.138 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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) |
| 2026-07-29 00:00 |
20:48:32.78 |
+03:27:28.0 |
HIP 102680 |
11.66 |
| 2026-07-29 12:00 |
20:48:30.81 |
+03:27:21.9 |
HIP 102680 |
11.68 |
| 2026-07-30 00:00 |
20:48:28.84 |
+03:27:15.7 |
HIP 102680 |
11.73 |
| 2026-07-30 12:00 |
20:48:26.87 |
+03:27:09.4 |
HIP 102680 |
11.80 |
| 2026-07-31 00:00 |
20:48:24.90 |
+03:27:03.0 |
HIP 102680 |
11.89 |
| 2026-07-31 12:00 |
20:48:22.92 |
+03:26:56.5 |
HIP 102680 |
12.01 |
| 2026-08-01 00:00 |
20:48:20.95 |
+03:26:50.0 |
HIP 102631 |
11.81 |
| 2026-08-01 12:00 |
20:48:18.97 |
+03:26:43.3 |
HIP 102631 |
11.39 |
| 2026-08-02 00:00 |
20:48:17.00 |
+03:26:36.5 |
HIP 102631 |
10.98 |
| 2026-08-02 12:00 |
20:48:15.02 |
+03:26:29.6 |
HIP 102631 |
10.57 |
| 2026-08-03 00:00 |
20:48:13.05 |
+03:26:22.6 |
HIP 102631 |
10.17 |
| 2026-08-03 12:00 |
20:48:11.07 |
+03:26:15.6 |
HIP 102631 |
9.78 |
| 2026-08-04 00:00 |
20:48:09.10 |
+03:26:08.4 |
HIP 102631 |
9.39 |
| 2026-08-04 12:00 |
20:48:07.13 |
+03:26:01.2 |
HIP 102631 |
9.02 |
| 2026-08-05 00:00 |
20:48:05.15 |
+03:25:53.8 |
HIP 102631 |
8.66 |
| 2026-08-05 12:00 |
20:48:03.18 |
+03:25:46.4 |
HIP 102631 |
8.32 |
| 2026-08-06 00:00 |
20:48:01.21 |
+03:25:38.8 |
HIP 102631 |
7.99 |
| 2026-08-06 12:00 |
20:47:59.24 |
+03:25:31.2 |
HIP 102631 |
7.68 |
| 2026-08-07 00:00 |
20:47:57.27 |
+03:25:23.4 |
HIP 102631 |
7.39 |
| 2026-08-07 12:00 |
20:47:55.30 |
+03:25:15.6 |
HIP 102631 |
7.12 |
| 2026-08-08 00:00 |
20:47:53.34 |
+03:25:07.7 |
HIP 102631 |
6.88 |
| 2026-08-08 12:00 |
20:47:51.37 |
+03:24:59.7 |
HIP 102631 |
6.67 |
| 2026-08-09 00:00 |
20:47:49.41 |
+03:24:51.6 |
HIP 102631 |
6.49 |
| 2026-08-09 12:00 |
20:47:47.45 |
+03:24:43.4 |
HIP 102631 |
6.34 |
| 2026-08-10 00:00 |
20:47:45.49 |
+03:24:35.1 |
HIP 102631 |
6.23 |
| 2026-08-10 12:00 |
20:47:43.53 |
+03:24:26.8 |
HIP 102631 |
6.16 |
| 2026-08-11 00:00 |
20:47:41.58 |
+03:24:18.3 |
HIP 102631 |
6.12 |
| 2026-08-11 12:00 |
20:47:39.63 |
+03:24:09.8 |
HIP 102631 |
6.13 |
| 2026-08-12 00:00 |
20:47:37.68 |
+03:24:01.2 |
HIP 102631 |
6.18 |
| 2026-08-12 12:00 |
20:47:35.74 |
+03:23:52.5 |
HIP 102631 |
6.27 |
| 2026-08-13 00:00 |
20:47:33.80 |
+03:23:43.7 |
HIP 102631 |
6.39 |
| 2026-08-13 12:00 |
20:47:31.86 |
+03:23:34.8 |
HIP 102631 |
6.55 |
| 2026-08-14 00:00 |
20:47:29.92 |
+03:23:25.8 |
HIP 102631 |
6.74 |
| 2026-08-14 12:00 |
20:47:27.99 |
+03:23:16.8 |
HIP 102631 |
6.97 |
| 2026-08-15 00:00 |
20:47:26.06 |
+03:23:07.7 |
HIP 102631 |
7.22 |
| 2026-08-15 12:00 |
20:47:24.14 |
+03:22:58.5 |
HIP 102631 |
7.49 |
| 2026-08-16 00:00 |
20:47:22.22 |
+03:22:49.2 |
HIP 102631 |
7.78 |
| 2026-08-16 12:00 |
20:47:20.31 |
+03:22:39.8 |
HIP 102631 |
8.10 |
| 2026-08-17 00:00 |
20:47:18.40 |
+03:22:30.4 |
HIP 102631 |
8.43 |
| 2026-08-17 12:00 |
20:47:16.49 |
+03:22:20.9 |
HIP 102631 |
8.77 |
| 2026-08-18 00:00 |
20:47:14.59 |
+03:22:11.3 |
HIP 102631 |
9.13 |
| 2026-08-18 12:00 |
20:47:12.69 |
+03:22:01.6 |
HIP 102631 |
9.50 |
| 2026-08-19 00:00 |
20:47:10.80 |
+03:21:51.9 |
HIP 102631 |
9.88 |