メタデータ
| 項目 |
値 |
| Designation |
C/1947 O1 (Wirtanen) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1947-07-16T20:09:37.615680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:07Z |
| Obs used |
3 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1948-03-29.0000000 |
| e |
1.01675158 |
| q (au) |
2.807881 |
| a (au) |
-167.618847 |
| i (deg) |
97.324802 |
| Ω (om, deg) |
311.764379 |
| ω (w, deg) |
8.848565 |
| M (ma, deg) |
0.116341 |
等級
散乱 + 全体線形
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-03-26 00:00 |
09:17:46.66 |
+28:47:13.7 |
HIP 45617 |
13.60 |
| 2026-03-26 12:00 |
09:17:45.82 |
+28:47:13.9 |
HIP 45617 |
13.63 |
| 2026-03-27 00:00 |
09:17:45.00 |
+28:47:14.1 |
HIP 45617 |
13.65 |
| 2026-03-27 12:00 |
09:17:44.18 |
+28:47:14.2 |
HIP 45617 |
13.68 |
| 2026-03-28 00:00 |
09:17:43.37 |
+28:47:14.2 |
HIP 45617 |
13.71 |
| 2026-03-28 12:00 |
09:17:42.56 |
+28:47:14.2 |
HIP 45617 |
13.74 |
| 2026-03-29 00:00 |
09:17:41.77 |
+28:47:14.2 |
HIP 45617 |
13.77 |
| 2026-03-29 12:00 |
09:17:40.98 |
+28:47:14.1 |
HIP 45617 |
13.80 |
| 2026-03-30 00:00 |
09:17:40.21 |
+28:47:13.9 |
HIP 45617 |
13.83 |
| 2026-03-30 12:00 |
09:17:39.44 |
+28:47:13.7 |
HIP 45617 |
13.87 |
| 2026-03-31 00:00 |
09:17:38.68 |
+28:47:13.4 |
HIP 45617 |
13.90 |
| 2026-03-31 12:00 |
09:17:37.92 |
+28:47:13.1 |
HIP 45617 |
13.93 |
| 2026-04-01 00:00 |
09:17:37.18 |
+28:47:12.7 |
HIP 45617 |
13.97 |
| 2026-04-01 12:00 |
09:17:36.44 |
+28:47:12.3 |
HIP 45617 |
14.00 |
| 2026-04-02 00:00 |
09:17:35.72 |
+28:47:11.8 |
HIP 45617 |
14.04 |
| 2026-04-02 12:00 |
09:17:35.00 |
+28:47:11.3 |
HIP 45617 |
14.08 |
| 2026-04-03 00:00 |
09:17:34.29 |
+28:47:10.7 |
HIP 45617 |
14.11 |
| 2026-04-03 12:00 |
09:17:33.59 |
+28:47:10.0 |
HIP 45617 |
14.15 |
| 2026-04-04 00:00 |
09:17:32.90 |
+28:47:09.4 |
HIP 45617 |
14.18 |
| 2026-04-04 12:00 |
09:17:32.21 |
+28:47:08.6 |
HIP 45617 |
14.22 |
| 2026-04-05 00:00 |
09:17:31.54 |
+28:47:07.8 |
HIP 45617 |
14.26 |
| 2026-04-05 12:00 |
09:17:30.87 |
+28:47:07.0 |
HIP 45617 |
14.29 |
| 2026-04-06 00:00 |
09:17:30.22 |
+28:47:06.1 |
HIP 45617 |
14.33 |
| 2026-04-06 12:00 |
09:17:29.57 |
+28:47:05.1 |
HIP 45617 |
14.37 |
| 2026-04-07 00:00 |
09:17:28.93 |
+28:47:04.1 |
HIP 45617 |
14.40 |
| 2026-04-07 12:00 |
09:17:28.30 |
+28:47:03.0 |
HIP 45617 |
14.44 |
| 2026-04-08 00:00 |
09:17:27.68 |
+28:47:01.9 |
HIP 45617 |
14.47 |
| 2026-04-08 12:00 |
09:17:27.07 |
+28:47:00.7 |
HIP 45617 |
14.51 |
| 2026-04-09 00:00 |
09:17:26.46 |
+28:46:59.5 |
HIP 45617 |
14.54 |
| 2026-04-09 12:00 |
09:17:25.87 |
+28:46:58.3 |
HIP 45617 |
14.58 |
| 2026-04-10 00:00 |
09:17:25.29 |
+28:46:56.9 |
HIP 45617 |
14.61 |
| 2026-04-10 12:00 |
09:17:24.71 |
+28:46:55.6 |
HIP 45617 |
14.64 |
| 2026-04-11 00:00 |
09:17:24.15 |
+28:46:54.1 |
HIP 45617 |
14.68 |
| 2026-04-11 12:00 |
09:17:23.59 |
+28:46:52.6 |
HIP 45617 |
14.71 |
| 2026-04-12 00:00 |
09:17:23.05 |
+28:46:51.1 |
HIP 45617 |
14.74 |
| 2026-04-12 12:00 |
09:17:22.51 |
+28:46:49.5 |
HIP 45617 |
14.77 |
| 2026-04-13 00:00 |
09:17:21.98 |
+28:46:47.9 |
HIP 45617 |
14.80 |
| 2026-04-13 12:00 |
09:17:21.46 |
+28:46:46.2 |
HIP 45617 |
14.83 |
| 2026-04-14 00:00 |
09:17:20.96 |
+28:46:44.5 |
HIP 45617 |
14.85 |
| 2026-04-14 12:00 |
09:17:20.46 |
+28:46:42.7 |
HIP 45617 |
14.88 |
| 2026-04-15 00:00 |
09:17:19.97 |
+28:46:40.8 |
HIP 45617 |
14.91 |
| 2026-04-15 12:00 |
09:17:19.49 |
+28:46:39.0 |
HIP 45617 |
14.93 |
| 2026-04-16 00:00 |
09:17:19.02 |
+28:46:37.0 |
HIP 45617 |
14.96 |