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 |
0.999 |
| gb |
-0.507 |
| 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 |
16:25:55.97 |
-41:39:37.7 |
HIP 80428 |
11.53 |
| 2026-07-29 12:00 |
16:25:55.11 |
-41:39:31.2 |
HIP 80428 |
11.34 |
| 2026-07-30 00:00 |
16:25:54.26 |
-41:39:24.8 |
HIP 80428 |
11.15 |
| 2026-07-30 12:00 |
16:25:53.42 |
-41:39:18.3 |
HIP 80428 |
10.96 |
| 2026-07-31 00:00 |
16:25:52.60 |
-41:39:11.9 |
HIP 80428 |
10.77 |
| 2026-07-31 12:00 |
16:25:51.78 |
-41:39:05.4 |
HIP 80428 |
10.59 |
| 2026-08-01 00:00 |
16:25:50.98 |
-41:38:59.0 |
HIP 80428 |
10.41 |
| 2026-08-01 12:00 |
16:25:50.19 |
-41:38:52.5 |
HIP 80428 |
10.23 |
| 2026-08-02 00:00 |
16:25:49.41 |
-41:38:46.0 |
HIP 80428 |
10.05 |
| 2026-08-02 12:00 |
16:25:48.64 |
-41:38:39.5 |
HIP 80428 |
9.87 |
| 2026-08-03 00:00 |
16:25:47.88 |
-41:38:33.0 |
HIP 80428 |
9.70 |
| 2026-08-03 12:00 |
16:25:47.13 |
-41:38:26.5 |
HIP 80428 |
9.53 |
| 2026-08-04 00:00 |
16:25:46.40 |
-41:38:20.1 |
HIP 80428 |
9.36 |
| 2026-08-04 12:00 |
16:25:45.68 |
-41:38:13.6 |
HIP 80428 |
9.19 |
| 2026-08-05 00:00 |
16:25:44.97 |
-41:38:07.1 |
HIP 80428 |
9.03 |
| 2026-08-05 12:00 |
16:25:44.27 |
-41:38:00.6 |
HIP 80428 |
8.87 |
| 2026-08-06 00:00 |
16:25:43.58 |
-41:37:54.1 |
HIP 80428 |
8.71 |
| 2026-08-06 12:00 |
16:25:42.91 |
-41:37:47.6 |
HIP 80428 |
8.55 |
| 2026-08-07 00:00 |
16:25:42.25 |
-41:37:41.1 |
HIP 80428 |
8.39 |
| 2026-08-07 12:00 |
16:25:41.60 |
-41:37:34.6 |
HIP 80428 |
8.24 |
| 2026-08-08 00:00 |
16:25:40.96 |
-41:37:28.1 |
HIP 80428 |
8.09 |
| 2026-08-08 12:00 |
16:25:40.33 |
-41:37:21.6 |
HIP 80428 |
7.94 |
| 2026-08-09 00:00 |
16:25:39.72 |
-41:37:15.1 |
HIP 80428 |
7.80 |
| 2026-08-09 12:00 |
16:25:39.12 |
-41:37:08.6 |
HIP 80428 |
7.66 |
| 2026-08-10 00:00 |
16:25:38.53 |
-41:37:02.1 |
HIP 80428 |
7.52 |
| 2026-08-10 12:00 |
16:25:37.95 |
-41:36:55.6 |
HIP 80428 |
7.38 |
| 2026-08-11 00:00 |
16:25:37.39 |
-41:36:49.1 |
HIP 80428 |
7.24 |
| 2026-08-11 12:00 |
16:25:36.84 |
-41:36:42.6 |
HIP 80428 |
7.11 |
| 2026-08-12 00:00 |
16:25:36.30 |
-41:36:36.2 |
HIP 80428 |
6.99 |
| 2026-08-12 12:00 |
16:25:35.77 |
-41:36:29.7 |
HIP 80428 |
6.86 |
| 2026-08-13 00:00 |
16:25:35.26 |
-41:36:23.2 |
HIP 80428 |
6.74 |
| 2026-08-13 12:00 |
16:25:34.75 |
-41:36:16.8 |
HIP 80428 |
6.62 |
| 2026-08-14 00:00 |
16:25:34.27 |
-41:36:10.3 |
HIP 80428 |
6.50 |
| 2026-08-14 12:00 |
16:25:33.79 |
-41:36:03.9 |
HIP 80428 |
6.39 |
| 2026-08-15 00:00 |
16:25:33.33 |
-41:35:57.4 |
HIP 80428 |
6.28 |
| 2026-08-15 12:00 |
16:25:32.88 |
-41:35:51.0 |
HIP 80428 |
6.18 |
| 2026-08-16 00:00 |
16:25:32.44 |
-41:35:44.6 |
HIP 80428 |
6.08 |
| 2026-08-16 12:00 |
16:25:32.01 |
-41:35:38.2 |
HIP 80428 |
5.98 |
| 2026-08-17 00:00 |
16:25:31.60 |
-41:35:31.8 |
HIP 80428 |
5.88 |
| 2026-08-17 12:00 |
16:25:31.20 |
-41:35:25.4 |
HIP 80428 |
5.79 |
| 2026-08-18 00:00 |
16:25:30.82 |
-41:35:19.0 |
HIP 80428 |
5.71 |
| 2026-08-18 12:00 |
16:25:30.44 |
-41:35:12.6 |
HIP 80428 |
5.63 |
| 2026-08-19 00:00 |
16:25:30.08 |
-41:35:06.3 |
HIP 80428 |
5.55 |