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) |
| 2026-09-20 00:00 |
16:25:34.16 |
-41:29:03.7 |
HIP 80428 |
8.36 |
| 2026-09-20 12:00 |
16:25:34.64 |
-41:28:59.1 |
HIP 80428 |
8.47 |
| 2026-09-21 00:00 |
16:25:35.14 |
-41:28:54.4 |
HIP 80428 |
8.60 |
| 2026-09-21 12:00 |
16:25:35.64 |
-41:28:49.8 |
HIP 80428 |
8.72 |
| 2026-09-22 00:00 |
16:25:36.17 |
-41:28:45.3 |
HIP 80428 |
8.84 |
| 2026-09-22 12:00 |
16:25:36.70 |
-41:28:40.7 |
HIP 80428 |
8.97 |
| 2026-09-23 00:00 |
16:25:37.24 |
-41:28:36.3 |
HIP 80428 |
9.09 |
| 2026-09-23 12:00 |
16:25:37.80 |
-41:28:31.8 |
HIP 80428 |
9.22 |
| 2026-09-24 00:00 |
16:25:38.37 |
-41:28:27.4 |
HIP 80428 |
9.35 |
| 2026-09-24 12:00 |
16:25:38.95 |
-41:28:23.1 |
HIP 80428 |
9.48 |
| 2026-09-25 00:00 |
16:25:39.54 |
-41:28:18.8 |
HIP 80428 |
9.61 |
| 2026-09-25 12:00 |
16:25:40.15 |
-41:28:14.5 |
HIP 80428 |
9.74 |
| 2026-09-26 00:00 |
16:25:40.76 |
-41:28:10.3 |
HIP 80428 |
9.87 |
| 2026-09-26 12:00 |
16:25:41.39 |
-41:28:06.1 |
HIP 80428 |
10.01 |
| 2026-09-27 00:00 |
16:25:42.03 |
-41:28:01.9 |
HIP 80428 |
10.15 |
| 2026-09-27 12:00 |
16:25:42.69 |
-41:27:57.8 |
HIP 80428 |
10.28 |
| 2026-09-28 00:00 |
16:25:43.35 |
-41:27:53.7 |
HIP 80428 |
10.42 |
| 2026-09-28 12:00 |
16:25:44.03 |
-41:27:49.7 |
HIP 80428 |
10.56 |
| 2026-09-29 00:00 |
16:25:44.71 |
-41:27:45.8 |
HIP 80428 |
10.70 |
| 2026-09-29 12:00 |
16:25:45.41 |
-41:27:41.8 |
HIP 80428 |
10.85 |
| 2026-09-30 00:00 |
16:25:46.12 |
-41:27:37.9 |
HIP 80428 |
10.99 |
| 2026-09-30 12:00 |
16:25:46.84 |
-41:27:34.1 |
HIP 80428 |
11.14 |
| 2026-10-01 00:00 |
16:25:47.58 |
-41:27:30.3 |
HIP 80428 |
11.28 |
| 2026-10-01 12:00 |
16:25:48.32 |
-41:27:26.5 |
HIP 80428 |
11.43 |
| 2026-10-02 00:00 |
16:25:49.08 |
-41:27:22.8 |
HIP 80428 |
11.58 |
| 2026-10-02 12:00 |
16:25:49.85 |
-41:27:19.2 |
HIP 80428 |
11.73 |
| 2026-10-03 00:00 |
16:25:50.63 |
-41:27:15.5 |
HIP 80428 |
11.88 |
| 2026-10-03 12:00 |
16:25:51.42 |
-41:27:12.0 |
HIP 80428 |
12.04 |
| 2026-10-04 00:00 |
16:25:52.22 |
-41:27:08.4 |
HIP 80428 |
12.19 |
| 2026-10-04 12:00 |
16:25:53.03 |
-41:27:05.0 |
HIP 80428 |
12.35 |
| 2026-10-05 00:00 |
16:25:53.85 |
-41:27:01.5 |
HIP 80428 |
12.50 |
| 2026-10-05 12:00 |
16:25:54.69 |
-41:26:58.1 |
HIP 80428 |
12.66 |
| 2026-10-06 00:00 |
16:25:55.54 |
-41:26:54.8 |
HIP 80428 |
12.82 |
| 2026-10-06 12:00 |
16:25:56.39 |
-41:26:51.5 |
HIP 80428 |
12.99 |
| 2026-10-07 00:00 |
16:25:57.26 |
-41:26:48.3 |
HIP 80428 |
13.15 |
| 2026-10-07 12:00 |
16:25:58.14 |
-41:26:45.1 |
HIP 80428 |
13.31 |
| 2026-10-08 00:00 |
16:25:59.03 |
-41:26:41.9 |
HIP 80428 |
13.48 |
| 2026-10-08 12:00 |
16:25:59.93 |
-41:26:38.8 |
HIP 80428 |
13.65 |
| 2026-10-09 00:00 |
16:26:00.84 |
-41:26:35.8 |
HIP 80428 |
13.81 |
| 2026-10-09 12:00 |
16:26:01.76 |
-41:26:32.8 |
HIP 80428 |
13.98 |
| 2026-10-10 00:00 |
16:26:02.69 |
-41:26:29.8 |
HIP 80428 |
14.15 |
| 2026-10-10 12:00 |
16:26:03.63 |
-41:26:26.9 |
HIP 80428 |
14.33 |
| 2026-10-11 00:00 |
16:26:04.58 |
-41:26:24.1 |
HIP 80428 |
14.50 |