メタデータ
| 項目 |
値 |
| Designation |
C/2001 O2 (NEAT) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-10-17T08:10:25.610880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:10Z |
| Obs used |
73 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2001-09-20.0000000 |
| e |
0.99779815 |
| q (au) |
4.819418 |
| a (au) |
2188.798835 |
| i (deg) |
90.926212 |
| Ω (om, deg) |
328.716022 |
| ω (w, deg) |
280.894802 |
| M (ma, deg) |
0.006773 |
等級
散乱 + 全体線形
$$
M_a = (7.744 + 3.176\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.744 |
| n |
3.176 |
| gf |
0.893 |
| gb |
-0.966 |
| k |
1.000 |
| δ90 |
4.079 |
| 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) |
| 2026-05-12 00:00 |
20:19:27.39 |
+46:31:32.4 |
HIP 100131 |
7.39 |
| 2026-05-12 12:00 |
20:19:26.14 |
+46:32:07.0 |
HIP 100131 |
7.11 |
| 2026-05-13 00:00 |
20:19:24.85 |
+46:32:41.5 |
HIP 100131 |
6.87 |
| 2026-05-13 12:00 |
20:19:23.54 |
+46:33:15.9 |
HIP 100131 |
6.68 |
| 2026-05-14 00:00 |
20:19:22.20 |
+46:33:50.1 |
HIP 100131 |
6.53 |
| 2026-05-14 12:00 |
20:19:20.83 |
+46:34:24.2 |
HIP 100131 |
6.43 |
| 2026-05-15 00:00 |
20:19:19.43 |
+46:34:58.2 |
HIP 100131 |
6.39 |
| 2026-05-15 12:00 |
20:19:18.00 |
+46:35:32.1 |
HIP 100131 |
6.40 |
| 2026-05-16 00:00 |
20:19:16.54 |
+46:36:05.8 |
HIP 100131 |
6.46 |
| 2026-05-16 12:00 |
20:19:15.05 |
+46:36:39.3 |
HIP 100131 |
6.57 |
| 2026-05-17 00:00 |
20:19:13.53 |
+46:37:12.8 |
HIP 100131 |
6.74 |
| 2026-05-17 12:00 |
20:19:11.98 |
+46:37:46.1 |
HIP 100131 |
6.94 |
| 2026-05-18 00:00 |
20:19:10.40 |
+46:38:19.2 |
HIP 100131 |
7.20 |
| 2026-05-18 12:00 |
20:19:08.80 |
+46:38:52.2 |
HIP 100131 |
7.48 |
| 2026-05-19 00:00 |
20:19:07.16 |
+46:39:25.0 |
HIP 100131 |
7.81 |
| 2026-05-19 12:00 |
20:19:05.50 |
+46:39:57.7 |
HIP 100131 |
8.16 |
| 2026-05-20 00:00 |
20:19:03.81 |
+46:40:30.2 |
HIP 100131 |
8.53 |
| 2026-05-20 12:00 |
20:19:02.09 |
+46:41:02.6 |
HIP 100131 |
8.93 |
| 2026-05-21 00:00 |
20:19:00.34 |
+46:41:34.8 |
HIP 100131 |
9.35 |
| 2026-05-21 12:00 |
20:18:58.56 |
+46:42:06.9 |
HIP 100131 |
9.79 |
| 2026-05-22 00:00 |
20:18:56.75 |
+46:42:38.7 |
HIP 100131 |
10.24 |
| 2026-05-22 12:00 |
20:18:54.92 |
+46:43:10.5 |
HIP 100131 |
10.70 |
| 2026-05-23 00:00 |
20:18:53.06 |
+46:43:42.0 |
HIP 100131 |
11.17 |
| 2026-05-23 12:00 |
20:18:51.17 |
+46:44:13.4 |
HIP 100131 |
11.66 |
| 2026-05-24 00:00 |
20:18:49.25 |
+46:44:44.6 |
HIP 100131 |
12.15 |
| 2026-05-24 12:00 |
20:18:47.31 |
+46:45:15.6 |
HIP 100131 |
12.65 |
| 2026-05-25 00:00 |
20:18:45.34 |
+46:45:46.4 |
HIP 100250 |
12.90 |
| 2026-05-25 12:00 |
20:18:43.34 |
+46:46:17.1 |
HIP 100250 |
13.05 |
| 2026-05-26 00:00 |
20:18:41.31 |
+46:46:47.6 |
HIP 100250 |
13.24 |
| 2026-05-26 12:00 |
20:18:39.26 |
+46:47:17.9 |
HIP 100250 |
13.46 |
| 2026-05-27 00:00 |
20:18:37.18 |
+46:47:48.0 |
HIP 100250 |
13.71 |
| 2026-05-27 12:00 |
20:18:35.08 |
+46:48:17.9 |
HIP 100250 |
13.99 |
| 2026-05-28 00:00 |
20:18:32.94 |
+46:48:47.7 |
HIP 100250 |
14.29 |
| 2026-05-28 12:00 |
20:18:30.78 |
+46:49:17.2 |
HIP 100250 |
14.61 |
| 2026-05-29 00:00 |
20:18:28.60 |
+46:49:46.6 |
HIP 100250 |
14.96 |
| 2026-05-29 12:00 |
20:18:26.39 |
+46:50:15.7 |
HIP 100250 |
15.33 |
| 2026-05-30 00:00 |
20:18:24.15 |
+46:50:44.7 |
HIP 100250 |
15.72 |
| 2026-05-30 12:00 |
20:18:21.89 |
+46:51:13.4 |
HIP 100250 |
16.13 |
| 2026-05-31 00:00 |
20:18:19.60 |
+46:51:42.0 |
HIP 100250 |
16.55 |
| 2026-05-31 12:00 |
20:18:17.29 |
+46:52:10.4 |
HIP 100250 |
16.99 |
| 2026-06-01 00:00 |
20:18:14.95 |
+46:52:38.5 |
HIP 100250 |
17.45 |
| 2026-06-01 12:00 |
20:18:12.58 |
+46:53:06.5 |
HIP 100250 |
17.92 |
| 2026-06-02 00:00 |
20:18:10.19 |
+46:53:34.2 |
HIP 100250 |
18.40 |