メタデータ
| 項目 |
値 |
| Designation |
C/1948 T1 (Wirtanen) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1947-09-03T21:00:21.755520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:09Z |
| Obs used |
19 |
| NEO |
- |
| M1 |
6.000 |
| K1 |
8.250 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1949-11-26.0000000 |
| e |
1.00069715 |
| q (au) |
3.268165 |
| a (au) |
-4687.881007 |
| i (deg) |
155.078426 |
| Ω (om, deg) |
122.125436 |
| ω (w, deg) |
73.549407 |
| M (ma, deg) |
0.002500 |
等級
散乱 + 全体線形
$$
M_a = (-0.036 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
-0.036 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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) |
| 2026-05-12 00:00 |
16:29:34.79 |
-41:50:13.5 |
HIP 80759 |
12.06 |
| 2026-05-12 12:00 |
16:29:33.26 |
-41:50:13.1 |
HIP 80759 |
12.01 |
| 2026-05-13 00:00 |
16:29:31.73 |
-41:50:12.6 |
HIP 80759 |
11.97 |
| 2026-05-13 12:00 |
16:29:30.19 |
-41:50:12.1 |
HIP 80759 |
11.93 |
| 2026-05-14 00:00 |
16:29:28.65 |
-41:50:11.5 |
HIP 80759 |
11.90 |
| 2026-05-14 12:00 |
16:29:27.10 |
-41:50:10.8 |
HIP 80759 |
11.88 |
| 2026-05-15 00:00 |
16:29:25.55 |
-41:50:10.1 |
HIP 80759 |
11.86 |
| 2026-05-15 12:00 |
16:29:24.00 |
-41:50:09.3 |
HIP 80759 |
11.86 |
| 2026-05-16 00:00 |
16:29:22.45 |
-41:50:08.5 |
HIP 80759 |
11.86 |
| 2026-05-16 12:00 |
16:29:20.89 |
-41:50:07.6 |
HIP 80759 |
11.87 |
| 2026-05-17 00:00 |
16:29:19.33 |
-41:50:06.7 |
HIP 80759 |
11.89 |
| 2026-05-17 12:00 |
16:29:17.76 |
-41:50:05.7 |
HIP 80759 |
11.91 |
| 2026-05-18 00:00 |
16:29:16.19 |
-41:50:04.6 |
HIP 80759 |
11.95 |
| 2026-05-18 12:00 |
16:29:14.62 |
-41:50:03.5 |
HIP 80759 |
11.99 |
| 2026-05-19 00:00 |
16:29:13.05 |
-41:50:02.3 |
HIP 80759 |
12.04 |
| 2026-05-19 12:00 |
16:29:11.47 |
-41:50:01.1 |
HIP 80759 |
12.10 |
| 2026-05-20 00:00 |
16:29:09.89 |
-41:49:59.8 |
HIP 80759 |
12.17 |
| 2026-05-20 12:00 |
16:29:08.31 |
-41:49:58.5 |
HIP 80759 |
12.24 |
| 2026-05-21 00:00 |
16:29:06.73 |
-41:49:57.1 |
HIP 80759 |
12.32 |
| 2026-05-21 12:00 |
16:29:05.14 |
-41:49:55.6 |
HIP 80759 |
12.41 |
| 2026-05-22 00:00 |
16:29:03.55 |
-41:49:54.1 |
HIP 80746 |
12.46 |
| 2026-05-22 12:00 |
16:29:01.96 |
-41:49:52.6 |
HIP 80746 |
12.47 |
| 2026-05-23 00:00 |
16:29:00.37 |
-41:49:50.9 |
HIP 80746 |
12.48 |
| 2026-05-23 12:00 |
16:28:58.78 |
-41:49:49.3 |
HIP 80746 |
12.50 |
| 2026-05-24 00:00 |
16:28:57.19 |
-41:49:47.5 |
HIP 80746 |
12.52 |
| 2026-05-24 12:00 |
16:28:55.59 |
-41:49:45.7 |
HIP 80746 |
12.55 |
| 2026-05-25 00:00 |
16:28:53.99 |
-41:49:43.9 |
HIP 80746 |
12.59 |
| 2026-05-25 12:00 |
16:28:52.40 |
-41:49:42.0 |
HIP 80746 |
12.63 |
| 2026-05-26 00:00 |
16:28:50.80 |
-41:49:40.1 |
HIP 80746 |
12.68 |
| 2026-05-26 12:00 |
16:28:49.20 |
-41:49:38.1 |
HIP 80746 |
12.73 |
| 2026-05-27 00:00 |
16:28:47.60 |
-41:49:36.0 |
HIP 80746 |
12.79 |
| 2026-05-27 12:00 |
16:28:45.99 |
-41:49:33.9 |
HIP 80746 |
12.86 |
| 2026-05-28 00:00 |
16:28:44.39 |
-41:49:31.7 |
HIP 80746 |
12.93 |
| 2026-05-28 12:00 |
16:28:42.79 |
-41:49:29.5 |
HIP 80746 |
13.01 |
| 2026-05-29 00:00 |
16:28:41.19 |
-41:49:27.3 |
HIP 80746 |
13.09 |
| 2026-05-29 12:00 |
16:28:39.58 |
-41:49:24.9 |
HIP 80746 |
13.18 |
| 2026-05-30 00:00 |
16:28:37.98 |
-41:49:22.6 |
HIP 80746 |
13.28 |
| 2026-05-30 12:00 |
16:28:36.37 |
-41:49:20.1 |
HIP 80746 |
13.38 |
| 2026-05-31 00:00 |
16:28:34.77 |
-41:49:17.6 |
HIP 80746 |
13.48 |
| 2026-05-31 12:00 |
16:28:33.17 |
-41:49:15.1 |
HIP 80746 |
13.59 |
| 2026-06-01 00:00 |
16:28:31.56 |
-41:49:12.5 |
HIP 80746 |
13.71 |
| 2026-06-01 12:00 |
16:28:29.96 |
-41:49:09.9 |
HIP 80746 |
13.83 |
| 2026-06-02 00:00 |
16:28:28.36 |
-41:49:07.2 |
HIP 80746 |
13.96 |