メタデータ
| 項目 |
値 |
| Designation |
C/1987 T1 (Levy) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1987-09-09T04:04:28.231680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:33Z |
| Obs used |
18 |
| NEO |
- |
| M1 |
9.200 |
| K1 |
31.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1987-10-24.0000000 |
| e |
0.99999043 |
| q (au) |
0.515261 |
| a (au) |
53860.674252 |
| i (deg) |
62.532659 |
| Ω (om, deg) |
143.730188 |
| ω (w, deg) |
13.191234 |
| M (ma, deg) |
0.000004 |
等級
散乱 + 全体線形
$$
M_a = (7.708 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.708 |
| n |
6.000 |
| gf |
0.994 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.999 |
| 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 |
21:54:58.86 |
-15:22:58.8 |
HIP 108176 |
7.51 |
| 2026-03-26 12:00 |
21:55:00.30 |
-15:22:52.5 |
HIP 108176 |
7.39 |
| 2026-03-27 00:00 |
21:55:01.73 |
-15:22:46.3 |
HIP 108176 |
7.30 |
| 2026-03-27 12:00 |
21:55:03.15 |
-15:22:40.1 |
HIP 108176 |
7.22 |
| 2026-03-28 00:00 |
21:55:04.56 |
-15:22:34.0 |
HIP 108176 |
7.16 |
| 2026-03-28 12:00 |
21:55:05.96 |
-15:22:27.9 |
HIP 108176 |
7.12 |
| 2026-03-29 00:00 |
21:55:07.35 |
-15:22:21.9 |
HIP 108176 |
7.09 |
| 2026-03-29 12:00 |
21:55:08.73 |
-15:22:16.0 |
HIP 108176 |
7.08 |
| 2026-03-30 00:00 |
21:55:10.10 |
-15:22:10.1 |
HIP 108176 |
7.09 |
| 2026-03-30 12:00 |
21:55:11.46 |
-15:22:04.3 |
HIP 108176 |
7.12 |
| 2026-03-31 00:00 |
21:55:12.81 |
-15:21:58.5 |
HIP 108176 |
7.16 |
| 2026-03-31 12:00 |
21:55:14.14 |
-15:21:52.8 |
HIP 108176 |
7.22 |
| 2026-04-01 00:00 |
21:55:15.47 |
-15:21:47.2 |
HIP 108176 |
7.29 |
| 2026-04-01 12:00 |
21:55:16.79 |
-15:21:41.6 |
HIP 108176 |
7.38 |
| 2026-04-02 00:00 |
21:55:18.10 |
-15:21:36.1 |
HIP 108176 |
7.48 |
| 2026-04-02 12:00 |
21:55:19.39 |
-15:21:30.7 |
HIP 108176 |
7.59 |
| 2026-04-03 00:00 |
21:55:20.68 |
-15:21:25.3 |
HIP 108176 |
7.71 |
| 2026-04-03 12:00 |
21:55:21.95 |
-15:21:20.0 |
HIP 108176 |
7.84 |
| 2026-04-04 00:00 |
21:55:23.22 |
-15:21:14.7 |
HIP 108176 |
7.99 |
| 2026-04-04 12:00 |
21:55:24.47 |
-15:21:09.6 |
HIP 108176 |
8.14 |
| 2026-04-05 00:00 |
21:55:25.71 |
-15:21:04.4 |
HIP 108176 |
8.30 |
| 2026-04-05 12:00 |
21:55:26.94 |
-15:20:59.4 |
HIP 108176 |
8.46 |
| 2026-04-06 00:00 |
21:55:28.16 |
-15:20:54.4 |
HIP 108176 |
8.64 |
| 2026-04-06 12:00 |
21:55:29.37 |
-15:20:49.5 |
HIP 108176 |
8.82 |
| 2026-04-07 00:00 |
21:55:30.56 |
-15:20:44.6 |
HIP 108176 |
9.00 |
| 2026-04-07 12:00 |
21:55:31.74 |
-15:20:39.9 |
HIP 108176 |
9.19 |
| 2026-04-08 00:00 |
21:55:32.92 |
-15:20:35.1 |
HIP 108176 |
9.38 |
| 2026-04-08 12:00 |
21:55:34.08 |
-15:20:30.5 |
HIP 108176 |
9.57 |
| 2026-04-09 00:00 |
21:55:35.23 |
-15:20:25.9 |
HIP 108176 |
9.77 |
| 2026-04-09 12:00 |
21:55:36.36 |
-15:20:21.4 |
HIP 108176 |
9.97 |
| 2026-04-10 00:00 |
21:55:37.49 |
-15:20:17.0 |
HIP 108176 |
10.17 |
| 2026-04-10 12:00 |
21:55:38.60 |
-15:20:12.6 |
HIP 108176 |
10.38 |
| 2026-04-11 00:00 |
21:55:39.70 |
-15:20:08.3 |
HIP 108176 |
10.58 |
| 2026-04-11 12:00 |
21:55:40.79 |
-15:20:04.1 |
HIP 108176 |
10.79 |
| 2026-04-12 00:00 |
21:55:41.87 |
-15:20:00.0 |
HIP 108176 |
11.00 |
| 2026-04-12 12:00 |
21:55:42.93 |
-15:19:55.8 |
HIP 108176 |
11.20 |
| 2026-04-13 00:00 |
21:55:43.98 |
-15:19:51.8 |
HIP 108176 |
11.41 |
| 2026-04-13 12:00 |
21:55:45.02 |
-15:19:47.9 |
HIP 108176 |
11.62 |
| 2026-04-14 00:00 |
21:55:46.04 |
-15:19:44.0 |
HIP 108176 |
11.82 |
| 2026-04-14 12:00 |
21:55:47.06 |
-15:19:40.2 |
HIP 108176 |
12.03 |
| 2026-04-15 00:00 |
21:55:48.06 |
-15:19:36.5 |
HIP 108176 |
12.24 |
| 2026-04-15 12:00 |
21:55:49.05 |
-15:19:32.8 |
HIP 108176 |
12.44 |
| 2026-04-16 00:00 |
21:55:50.02 |
-15:19:29.3 |
HIP 108176 |
12.64 |