メタデータ
| 項目 |
値 |
| Designation |
C/1931 O1 (Nagata) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1931-06-11T17:58:51.191040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:03Z |
| Obs used |
33 |
| NEO |
- |
| M1 |
5.700 |
| K1 |
4.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1931-10-05.0000000 |
| e |
0.97845116 |
| q (au) |
1.046195 |
| a (au) |
48.549944 |
| i (deg) |
42.302413 |
| Ω (om, deg) |
192.252622 |
| ω (w, deg) |
320.091135 |
| M (ma, deg) |
0.335788 |
等級
散乱 + 全体線形
$$
M_a = (6.469 + 3.539\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.469 |
| n |
3.539 |
| gf |
0.994 |
| gb |
-0.700 |
| k |
0.800 |
| δ90 |
9.978 |
| 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 |
21:53:28.94 |
+17:06:21.0 |
HIP 108100 |
17.45 |
| 2026-05-12 12:00 |
21:53:29.10 |
+17:06:32.0 |
HIP 108100 |
17.58 |
| 2026-05-13 00:00 |
21:53:29.25 |
+17:06:42.9 |
HIP 108100 |
17.71 |
| 2026-05-13 12:00 |
21:53:29.38 |
+17:06:53.7 |
HIP 108100 |
17.84 |
| 2026-05-14 00:00 |
21:53:29.51 |
+17:07:04.5 |
HIP 108100 |
17.98 |
| 2026-05-14 12:00 |
21:53:29.62 |
+17:07:15.3 |
HIP 108100 |
18.12 |
| 2026-05-15 00:00 |
21:53:29.73 |
+17:07:26.0 |
HIP 108100 |
18.25 |
| 2026-05-15 12:00 |
21:53:29.82 |
+17:07:36.7 |
HIP 108100 |
18.39 |
| 2026-05-16 00:00 |
21:53:29.90 |
+17:07:47.3 |
HIP 108100 |
18.53 |
| 2026-05-16 12:00 |
21:53:29.96 |
+17:07:57.9 |
HIP 108100 |
18.68 |
| 2026-05-17 00:00 |
21:53:30.02 |
+17:08:08.4 |
HIP 108100 |
18.82 |
| 2026-05-17 12:00 |
21:53:30.06 |
+17:08:18.9 |
HIP 108100 |
18.97 |
| 2026-05-18 00:00 |
21:53:30.09 |
+17:08:29.3 |
HIP 108100 |
19.11 |
| 2026-05-18 12:00 |
21:53:30.11 |
+17:08:39.7 |
HIP 108100 |
19.26 |
| 2026-05-19 00:00 |
21:53:30.12 |
+17:08:50.0 |
HIP 108100 |
19.41 |
| 2026-05-19 12:00 |
21:53:30.12 |
+17:09:00.3 |
HIP 108100 |
19.56 |
| 2026-05-20 00:00 |
21:53:30.10 |
+17:09:10.5 |
HIP 108100 |
19.71 |
| 2026-05-20 12:00 |
21:53:30.08 |
+17:09:20.6 |
HIP 108100 |
19.86 |
| 2026-05-21 00:00 |
21:53:30.04 |
+17:09:30.7 |
HIP 108100 |
20.01 |
| 2026-05-21 12:00 |
21:53:29.99 |
+17:09:40.8 |
HIP 108100 |
20.17 |
| 2026-05-22 00:00 |
21:53:29.93 |
+17:09:50.8 |
HIP 108100 |
20.32 |
| 2026-05-22 12:00 |
21:53:29.85 |
+17:10:00.7 |
HIP 108100 |
20.47 |
| 2026-05-23 00:00 |
21:53:29.77 |
+17:10:10.6 |
HIP 108100 |
20.63 |
| 2026-05-23 12:00 |
21:53:29.67 |
+17:10:20.4 |
HIP 108100 |
20.78 |
| 2026-05-24 00:00 |
21:53:29.56 |
+17:10:30.1 |
HIP 108100 |
20.94 |
| 2026-05-24 12:00 |
21:53:29.44 |
+17:10:39.8 |
HIP 108100 |
21.10 |
| 2026-05-25 00:00 |
21:53:29.31 |
+17:10:49.4 |
HIP 108100 |
21.25 |
| 2026-05-25 12:00 |
21:53:29.17 |
+17:10:59.0 |
HIP 108100 |
21.41 |
| 2026-05-26 00:00 |
21:53:29.01 |
+17:11:08.5 |
HIP 108100 |
21.57 |
| 2026-05-26 12:00 |
21:53:28.85 |
+17:11:18.0 |
HIP 108100 |
21.73 |
| 2026-05-27 00:00 |
21:53:28.67 |
+17:11:27.3 |
HIP 108100 |
21.89 |
| 2026-05-27 12:00 |
21:53:28.48 |
+17:11:36.6 |
HIP 108100 |
22.04 |
| 2026-05-28 00:00 |
21:53:28.28 |
+17:11:45.9 |
HIP 108100 |
22.20 |
| 2026-05-28 12:00 |
21:53:28.07 |
+17:11:55.1 |
HIP 108100 |
22.36 |
| 2026-05-29 00:00 |
21:53:27.84 |
+17:12:04.2 |
HIP 108100 |
22.52 |
| 2026-05-29 12:00 |
21:53:27.61 |
+17:12:13.3 |
HIP 108100 |
22.68 |
| 2026-05-30 00:00 |
21:53:27.36 |
+17:12:22.2 |
HIP 108100 |
22.84 |
| 2026-05-30 12:00 |
21:53:27.10 |
+17:12:31.2 |
HIP 108100 |
23.00 |
| 2026-05-31 00:00 |
21:53:26.83 |
+17:12:40.0 |
HIP 108100 |
23.17 |
| 2026-05-31 12:00 |
21:53:26.55 |
+17:12:48.8 |
HIP 108100 |
23.33 |
| 2026-06-01 00:00 |
21:53:26.26 |
+17:12:57.5 |
HIP 107917 |
23.31 |
| 2026-06-01 12:00 |
21:53:25.96 |
+17:13:06.1 |
HIP 107917 |
23.27 |
| 2026-06-02 00:00 |
21:53:25.64 |
+17:13:14.7 |
HIP 107917 |
23.22 |