メタデータ
| 項目 |
値 |
| Designation |
P/2021 L2 (Leonard) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-07-24T13:05:37.386240Z |
| Orbit solution date (soln_date, UTC) |
2021-11-20T19:13:06Z |
| Obs used |
131 |
| NEO |
- |
| M1 |
16.200 |
| K1 |
11.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-06-08T09:29:49.689600Z |
| Discovery magnitude (MPC) |
20.31 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-07-26.0000000 |
| e |
0.52175163 |
| q (au) |
1.938550 |
| a (au) |
4.053438 |
| i (deg) |
21.068982 |
| Ω (om, deg) |
266.675736 |
| ω (w, deg) |
51.538655 |
| M (ma, deg) |
0.175655 |
等級
散乱 + 全体線形
$$
M_a = (18.492 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
18.492 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.965 |
| δ90 |
1.000 |
| 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 |
09:39:16.68 |
-03:44:52.3 |
HIP 47302 |
15.03 |
| 2026-07-29 12:00 |
09:39:36.61 |
-03:46:22.5 |
HIP 47358 |
17.41 |
| 2026-07-30 00:00 |
09:39:56.57 |
-03:47:53.4 |
HIP 47358 |
19.54 |
| 2026-07-30 12:00 |
09:40:16.56 |
-03:49:25.1 |
HIP 47358 |
22.68 |
| 2026-07-31 00:00 |
09:40:36.57 |
-03:50:57.5 |
HIP 47577 |
23.58 |
| 2026-07-31 12:00 |
09:40:56.61 |
-03:52:30.6 |
HIP 47577 |
18.37 |
| 2026-08-01 00:00 |
09:41:16.68 |
-03:54:04.5 |
HIP 47577 |
13.18 |
| 2026-08-01 12:00 |
09:41:36.77 |
-03:55:39.1 |
HIP 47577 |
8.04 |
| 2026-08-02 00:00 |
09:41:56.88 |
-03:57:14.4 |
HIP 47577 |
3.25 |
| 2026-08-02 12:00 |
09:42:17.02 |
-03:58:50.4 |
HIP 47577 |
3.45 |
| 2026-08-03 00:00 |
09:42:37.18 |
-04:00:27.1 |
HIP 47577 |
8.30 |
| 2026-08-03 12:00 |
09:42:57.36 |
-04:02:04.6 |
HIP 47577 |
13.49 |
| 2026-08-04 00:00 |
09:43:17.56 |
-04:03:42.8 |
HIP 47577 |
18.74 |
| 2026-08-04 12:00 |
09:43:37.79 |
-04:05:21.6 |
HIP 47577 |
24.02 |
| 2026-08-05 00:00 |
09:43:58.03 |
-04:07:01.2 |
HIP 47577 |
29.31 |
| 2026-08-05 12:00 |
09:44:18.30 |
-04:08:41.5 |
HIP 47781 |
30.89 |
| 2026-08-06 00:00 |
09:44:38.59 |
-04:10:22.5 |
HIP 47781 |
29.13 |
| 2026-08-06 12:00 |
09:44:58.89 |
-04:12:04.3 |
HIP 47781 |
28.27 |
| 2026-08-07 00:00 |
09:45:19.21 |
-04:13:46.7 |
HIP 47990 |
23.97 |
| 2026-08-07 12:00 |
09:45:39.56 |
-04:15:29.8 |
HIP 47990 |
18.70 |
| 2026-08-08 00:00 |
09:45:59.92 |
-04:17:13.6 |
HIP 47990 |
13.49 |
| 2026-08-08 12:00 |
09:46:20.29 |
-04:18:58.1 |
HIP 47990 |
8.46 |
| 2026-08-09 00:00 |
09:46:40.68 |
-04:20:43.3 |
HIP 47990 |
4.36 |
| 2026-08-09 12:00 |
09:47:01.09 |
-04:22:29.2 |
HIP 47990 |
4.94 |
| 2026-08-10 00:00 |
09:47:21.51 |
-04:24:15.8 |
HIP 47990 |
9.38 |
| 2026-08-10 12:00 |
09:47:41.95 |
-04:26:03.0 |
HIP 47990 |
14.49 |
| 2026-08-11 00:00 |
09:48:02.40 |
-04:27:51.0 |
HIP 47990 |
19.76 |
| 2026-08-11 12:00 |
09:48:22.86 |
-04:29:39.6 |
HIP 47990 |
25.10 |
| 2026-08-12 00:00 |
09:48:43.34 |
-04:31:28.9 |
HIP 48167 |
21.74 |
| 2026-08-12 12:00 |
09:49:03.83 |
-04:33:18.9 |
HIP 48167 |
19.22 |
| 2026-08-13 00:00 |
09:49:24.32 |
-04:35:09.5 |
HIP 48167 |
18.02 |
| 2026-08-13 12:00 |
09:49:44.83 |
-04:37:00.8 |
HIP 48167 |
18.40 |
| 2026-08-14 00:00 |
09:50:05.35 |
-04:38:52.8 |
HIP 48272 |
19.71 |
| 2026-08-14 12:00 |
09:50:25.87 |
-04:40:45.4 |
HIP 48272 |
16.90 |
| 2026-08-15 00:00 |
09:50:46.41 |
-04:42:38.7 |
HIP 48272 |
15.55 |
| 2026-08-15 12:00 |
09:51:06.95 |
-04:44:32.6 |
HIP 48272 |
16.03 |
| 2026-08-16 00:00 |
09:51:27.50 |
-04:46:27.2 |
HIP 48272 |
18.21 |
| 2026-08-16 12:00 |
09:51:48.05 |
-04:48:22.4 |
HIP 48272 |
21.58 |
| 2026-08-17 00:00 |
09:52:08.61 |
-04:50:18.3 |
HIP 48272 |
25.69 |
| 2026-08-17 12:00 |
09:52:29.17 |
-04:52:14.8 |
HIP 48272 |
30.22 |
| 2026-08-18 00:00 |
09:52:49.74 |
-04:54:12.0 |
HIP 48597 |
28.63 |
| 2026-08-18 12:00 |
09:53:10.31 |
-04:56:09.7 |
HIP 48597 |
23.14 |
| 2026-08-19 00:00 |
09:53:30.89 |
-04:58:08.1 |
HIP 48597 |
17.65 |