メタデータ
| 項目 |
値 |
| Designation |
P/2017 Y3 (Leonard) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-02-11T06:14:12.742080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:39Z |
| Obs used |
93 |
| NEO |
Yes |
| M1 |
16.500 |
| K1 |
11.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-02-20.0000000 |
| e |
0.87071088 |
| q (au) |
1.275381 |
| a (au) |
9.864564 |
| i (deg) |
27.585652 |
| Ω (om, deg) |
153.873913 |
| ω (w, deg) |
67.528786 |
| M (ma, deg) |
0.278039 |
等級
散乱 + 全体線形
$$
M_a = (15.771 + 4.270\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.771 |
| n |
4.270 |
| gf |
1.000 |
| gb |
-1.000 |
| 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 |
02:20:58.84 |
-09:46:59.9 |
HIP 11012 |
26.98 |
| 2026-07-29 12:00 |
02:20:59.71 |
-09:47:43.4 |
HIP 11012 |
27.53 |
| 2026-07-30 00:00 |
02:21:00.51 |
-09:48:27.2 |
HIP 11012 |
28.10 |
| 2026-07-30 12:00 |
02:21:01.26 |
-09:49:11.3 |
HIP 11012 |
28.69 |
| 2026-07-31 00:00 |
02:21:01.94 |
-09:49:55.7 |
HIP 11012 |
29.30 |
| 2026-07-31 12:00 |
02:21:02.57 |
-09:50:40.5 |
HIP 11012 |
29.92 |
| 2026-08-01 00:00 |
02:21:03.14 |
-09:51:25.6 |
HIP 11012 |
30.56 |
| 2026-08-01 12:00 |
02:21:03.64 |
-09:52:11.0 |
HIP 11012 |
31.22 |
| 2026-08-02 00:00 |
02:21:04.09 |
-09:52:56.7 |
HIP 11012 |
31.89 |
| 2026-08-02 12:00 |
02:21:04.48 |
-09:53:42.7 |
HIP 11012 |
32.58 |
| 2026-08-03 00:00 |
02:21:04.81 |
-09:54:29.0 |
HIP 11012 |
33.28 |
| 2026-08-03 12:00 |
02:21:05.07 |
-09:55:15.6 |
HIP 10869 |
33.06 |
| 2026-08-04 00:00 |
02:21:05.28 |
-09:56:02.5 |
HIP 10869 |
32.44 |
| 2026-08-04 12:00 |
02:21:05.42 |
-09:56:49.8 |
HIP 10869 |
31.80 |
| 2026-08-05 00:00 |
02:21:05.51 |
-09:57:37.3 |
HIP 10869 |
31.16 |
| 2026-08-05 12:00 |
02:21:05.53 |
-09:58:25.1 |
HIP 10869 |
30.51 |
| 2026-08-06 00:00 |
02:21:05.50 |
-09:59:13.2 |
HIP 10869 |
29.86 |
| 2026-08-06 12:00 |
02:21:05.40 |
-10:00:01.6 |
HIP 10869 |
29.21 |
| 2026-08-07 00:00 |
02:21:05.24 |
-10:00:50.3 |
HIP 10869 |
28.54 |
| 2026-08-07 12:00 |
02:21:05.03 |
-10:01:39.2 |
HIP 10869 |
27.88 |
| 2026-08-08 00:00 |
02:21:04.75 |
-10:02:28.4 |
HIP 10869 |
27.20 |
| 2026-08-08 12:00 |
02:21:04.41 |
-10:03:17.9 |
HIP 10869 |
26.53 |
| 2026-08-09 00:00 |
02:21:04.00 |
-10:04:07.7 |
HIP 10869 |
25.84 |
| 2026-08-09 12:00 |
02:21:03.54 |
-10:04:57.7 |
HIP 10869 |
25.16 |
| 2026-08-10 00:00 |
02:21:03.02 |
-10:05:48.0 |
HIP 10869 |
24.47 |
| 2026-08-10 12:00 |
02:21:02.43 |
-10:06:38.6 |
HIP 10869 |
23.77 |
| 2026-08-11 00:00 |
02:21:01.79 |
-10:07:29.4 |
HIP 10869 |
23.08 |
| 2026-08-11 12:00 |
02:21:01.08 |
-10:08:20.5 |
HIP 10869 |
22.38 |
| 2026-08-12 00:00 |
02:21:00.31 |
-10:09:11.8 |
HIP 10869 |
21.67 |
| 2026-08-12 12:00 |
02:20:59.48 |
-10:10:03.4 |
HIP 10869 |
20.97 |
| 2026-08-13 00:00 |
02:20:58.58 |
-10:10:55.2 |
HIP 10869 |
20.27 |
| 2026-08-13 12:00 |
02:20:57.63 |
-10:11:47.2 |
HIP 10869 |
19.56 |
| 2026-08-14 00:00 |
02:20:56.62 |
-10:12:39.5 |
HIP 10869 |
18.86 |
| 2026-08-14 12:00 |
02:20:55.54 |
-10:13:32.0 |
HIP 10869 |
18.17 |
| 2026-08-15 00:00 |
02:20:54.40 |
-10:14:24.7 |
HIP 10869 |
17.47 |
| 2026-08-15 12:00 |
02:20:53.21 |
-10:15:17.7 |
HIP 10869 |
16.79 |
| 2026-08-16 00:00 |
02:20:51.95 |
-10:16:10.8 |
HIP 10869 |
16.11 |
| 2026-08-16 12:00 |
02:20:50.63 |
-10:17:04.2 |
HIP 10869 |
15.45 |
| 2026-08-17 00:00 |
02:20:49.25 |
-10:17:57.8 |
HIP 10869 |
14.80 |
| 2026-08-17 12:00 |
02:20:47.80 |
-10:18:51.6 |
HIP 10869 |
14.17 |
| 2026-08-18 00:00 |
02:20:46.30 |
-10:19:45.6 |
HIP 10869 |
13.57 |
| 2026-08-18 12:00 |
02:20:44.74 |
-10:20:39.7 |
HIP 10869 |
13.00 |
| 2026-08-19 00:00 |
02:20:43.12 |
-10:21:34.1 |
HIP 10869 |
12.46 |