メタデータ
| 項目 |
値 |
| Designation |
C/1977 H1 (Helin) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1977-06-30T23:22:37.151040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:27Z |
| Obs used |
35 |
| NEO |
- |
| M1 |
14.600 |
| K1 |
10.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1977-04-22.0000000 |
| e |
0.99999249 |
| q (au) |
1.117547 |
| a (au) |
148777.258886 |
| i (deg) |
43.194938 |
| Ω (om, deg) |
20.138583 |
| ω (w, deg) |
249.358219 |
| M (ma, deg) |
359.999999 |
等級
散乱 + 全体線形
$$
M_a = (12.630 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.630 |
| n |
6.000 |
| 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) |
| 2026-07-29 00:00 |
03:45:39.06 |
+54:48:52.8 |
HIP 17575 |
15.04 |
| 2026-07-29 12:00 |
03:45:40.10 |
+54:49:07.2 |
HIP 17575 |
14.79 |
| 2026-07-30 00:00 |
03:45:41.13 |
+54:49:21.5 |
HIP 17575 |
14.54 |
| 2026-07-30 12:00 |
03:45:42.13 |
+54:49:35.9 |
HIP 17575 |
14.29 |
| 2026-07-31 00:00 |
03:45:43.12 |
+54:49:50.3 |
HIP 17575 |
14.04 |
| 2026-07-31 12:00 |
03:45:44.08 |
+54:50:04.6 |
HIP 17575 |
13.79 |
| 2026-08-01 00:00 |
03:45:45.03 |
+54:50:19.0 |
HIP 17575 |
13.54 |
| 2026-08-01 12:00 |
03:45:45.95 |
+54:50:33.4 |
HIP 17575 |
13.29 |
| 2026-08-02 00:00 |
03:45:46.85 |
+54:50:47.8 |
HIP 17575 |
13.05 |
| 2026-08-02 12:00 |
03:45:47.73 |
+54:51:02.3 |
HIP 17575 |
12.80 |
| 2026-08-03 00:00 |
03:45:48.59 |
+54:51:16.7 |
HIP 17575 |
12.56 |
| 2026-08-03 12:00 |
03:45:49.43 |
+54:51:31.1 |
HIP 17575 |
12.32 |
| 2026-08-04 00:00 |
03:45:50.25 |
+54:51:45.5 |
HIP 17575 |
12.07 |
| 2026-08-04 12:00 |
03:45:51.05 |
+54:52:00.0 |
HIP 17575 |
11.83 |
| 2026-08-05 00:00 |
03:45:51.83 |
+54:52:14.4 |
HIP 17575 |
11.59 |
| 2026-08-05 12:00 |
03:45:52.58 |
+54:52:28.8 |
HIP 17575 |
11.36 |
| 2026-08-06 00:00 |
03:45:53.32 |
+54:52:43.2 |
HIP 17575 |
11.12 |
| 2026-08-06 12:00 |
03:45:54.03 |
+54:52:57.7 |
HIP 17575 |
10.88 |
| 2026-08-07 00:00 |
03:45:54.72 |
+54:53:12.1 |
HIP 17575 |
10.65 |
| 2026-08-07 12:00 |
03:45:55.39 |
+54:53:26.5 |
HIP 17575 |
10.41 |
| 2026-08-08 00:00 |
03:45:56.04 |
+54:53:40.9 |
HIP 17575 |
10.18 |
| 2026-08-08 12:00 |
03:45:56.67 |
+54:53:55.3 |
HIP 17575 |
9.95 |
| 2026-08-09 00:00 |
03:45:57.27 |
+54:54:09.7 |
HIP 17575 |
9.72 |
| 2026-08-09 12:00 |
03:45:57.86 |
+54:54:24.1 |
HIP 17575 |
9.49 |
| 2026-08-10 00:00 |
03:45:58.42 |
+54:54:38.5 |
HIP 17575 |
9.26 |
| 2026-08-10 12:00 |
03:45:58.96 |
+54:54:52.9 |
HIP 17575 |
9.03 |
| 2026-08-11 00:00 |
03:45:59.47 |
+54:55:07.2 |
HIP 17575 |
8.81 |
| 2026-08-11 12:00 |
03:45:59.97 |
+54:55:21.6 |
HIP 17575 |
8.58 |
| 2026-08-12 00:00 |
03:46:00.44 |
+54:55:35.9 |
HIP 17575 |
8.35 |
| 2026-08-12 12:00 |
03:46:00.89 |
+54:55:50.3 |
HIP 17575 |
8.13 |
| 2026-08-13 00:00 |
03:46:01.32 |
+54:56:04.6 |
HIP 17575 |
7.91 |
| 2026-08-13 12:00 |
03:46:01.72 |
+54:56:18.9 |
HIP 17575 |
7.69 |
| 2026-08-14 00:00 |
03:46:02.11 |
+54:56:33.2 |
HIP 17575 |
7.47 |
| 2026-08-14 12:00 |
03:46:02.47 |
+54:56:47.4 |
HIP 17575 |
7.25 |
| 2026-08-15 00:00 |
03:46:02.81 |
+54:57:01.7 |
HIP 17575 |
7.03 |
| 2026-08-15 12:00 |
03:46:03.12 |
+54:57:15.9 |
HIP 17575 |
6.81 |
| 2026-08-16 00:00 |
03:46:03.42 |
+54:57:30.1 |
HIP 17575 |
6.59 |
| 2026-08-16 12:00 |
03:46:03.69 |
+54:57:44.3 |
HIP 17575 |
6.38 |
| 2026-08-17 00:00 |
03:46:03.94 |
+54:57:58.4 |
HIP 17575 |
6.16 |
| 2026-08-17 12:00 |
03:46:04.16 |
+54:58:12.5 |
HIP 17575 |
5.95 |
| 2026-08-18 00:00 |
03:46:04.37 |
+54:58:26.6 |
HIP 17575 |
5.74 |
| 2026-08-18 12:00 |
03:46:04.55 |
+54:58:40.7 |
HIP 17575 |
5.53 |
| 2026-08-19 00:00 |
03:46:04.71 |
+54:58:54.8 |
HIP 17575 |
5.32 |