メタデータ
| 項目 |
値 |
| Designation |
C/2017 W2 (Leonard) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-11-01T22:30:18.835200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:38Z |
| Obs used |
169 |
| NEO |
- |
| M1 |
10.900 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-12-26.0000000 |
| e |
0.71125672 |
| q (au) |
3.957327 |
| a (au) |
13.705348 |
| i (deg) |
98.179291 |
| Ω (om, deg) |
312.809062 |
| ω (w, deg) |
169.157714 |
| M (ma, deg) |
1.050179 |
等級
散乱 + 全体線形
$$
M_a = (10.278 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.278 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.700 |
| k |
0.800 |
| 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) |
| 2026-03-26 00:00 |
23:32:22.42 |
-54:57:58.3 |
HIP 116373 |
24.83 |
| 2026-03-26 12:00 |
23:32:32.43 |
-54:57:38.5 |
HIP 116373 |
23.79 |
| 2026-03-27 00:00 |
23:32:42.41 |
-54:57:19.5 |
HIP 116373 |
22.78 |
| 2026-03-27 12:00 |
23:32:52.37 |
-54:57:01.1 |
HIP 116373 |
21.83 |
| 2026-03-28 00:00 |
23:33:02.30 |
-54:56:43.6 |
HIP 116373 |
20.93 |
| 2026-03-28 12:00 |
23:33:12.21 |
-54:56:26.7 |
HIP 116373 |
20.08 |
| 2026-03-29 00:00 |
23:33:22.09 |
-54:56:10.6 |
HIP 116373 |
19.31 |
| 2026-03-29 12:00 |
23:33:31.95 |
-54:55:55.3 |
HIP 116373 |
18.60 |
| 2026-03-30 00:00 |
23:33:41.78 |
-54:55:40.7 |
HIP 116373 |
17.97 |
| 2026-03-30 12:00 |
23:33:51.58 |
-54:55:26.8 |
HIP 116373 |
17.42 |
| 2026-03-31 00:00 |
23:34:01.35 |
-54:55:13.7 |
HIP 116373 |
16.97 |
| 2026-03-31 12:00 |
23:34:11.10 |
-54:55:01.3 |
HIP 116373 |
16.62 |
| 2026-04-01 00:00 |
23:34:20.81 |
-54:54:49.6 |
HIP 116373 |
16.37 |
| 2026-04-01 12:00 |
23:34:30.50 |
-54:54:38.7 |
HIP 116373 |
16.23 |
| 2026-04-02 00:00 |
23:34:40.15 |
-54:54:28.5 |
HIP 116373 |
16.20 |
| 2026-04-02 12:00 |
23:34:49.78 |
-54:54:19.1 |
HIP 116373 |
16.27 |
| 2026-04-03 00:00 |
23:34:59.37 |
-54:54:10.4 |
HIP 116373 |
16.45 |
| 2026-04-03 12:00 |
23:35:08.93 |
-54:54:02.5 |
HIP 116373 |
16.72 |
| 2026-04-04 00:00 |
23:35:18.46 |
-54:53:55.3 |
HIP 116476 |
16.56 |
| 2026-04-04 12:00 |
23:35:27.95 |
-54:53:48.9 |
HIP 116476 |
15.96 |
| 2026-04-05 00:00 |
23:35:37.41 |
-54:53:43.2 |
HIP 116476 |
15.48 |
| 2026-04-05 12:00 |
23:35:46.84 |
-54:53:38.2 |
HIP 116476 |
15.12 |
| 2026-04-06 00:00 |
23:35:56.23 |
-54:53:34.0 |
HIP 116476 |
14.88 |
| 2026-04-06 12:00 |
23:36:05.58 |
-54:53:30.5 |
HIP 116476 |
14.78 |
| 2026-04-07 00:00 |
23:36:14.90 |
-54:53:27.8 |
HIP 116476 |
14.82 |
| 2026-04-07 12:00 |
23:36:24.18 |
-54:53:25.8 |
HIP 116476 |
14.99 |
| 2026-04-08 00:00 |
23:36:33.43 |
-54:53:24.6 |
HIP 116476 |
15.28 |
| 2026-04-08 12:00 |
23:36:42.63 |
-54:53:24.1 |
HIP 116476 |
15.69 |
| 2026-04-09 00:00 |
23:36:51.80 |
-54:53:24.4 |
HIP 116476 |
16.21 |
| 2026-04-09 12:00 |
23:37:00.93 |
-54:53:25.4 |
HIP 116476 |
16.83 |
| 2026-04-10 00:00 |
23:37:10.01 |
-54:53:27.2 |
HIP 116476 |
17.53 |
| 2026-04-10 12:00 |
23:37:19.06 |
-54:53:29.7 |
HIP 116476 |
18.30 |
| 2026-04-11 00:00 |
23:37:28.07 |
-54:53:32.9 |
HIP 116476 |
19.14 |
| 2026-04-11 12:00 |
23:37:37.03 |
-54:53:37.0 |
HIP 116476 |
20.03 |
| 2026-04-12 00:00 |
23:37:45.95 |
-54:53:41.7 |
HIP 116476 |
20.97 |
| 2026-04-12 12:00 |
23:37:54.83 |
-54:53:47.2 |
HIP 116476 |
21.95 |
| 2026-04-13 00:00 |
23:38:03.67 |
-54:53:53.5 |
HIP 116476 |
22.96 |
| 2026-04-13 12:00 |
23:38:12.46 |
-54:54:00.5 |
HIP 116476 |
24.00 |
| 2026-04-14 00:00 |
23:38:21.20 |
-54:54:08.2 |
HIP 116476 |
25.07 |
| 2026-04-14 12:00 |
23:38:29.90 |
-54:54:16.7 |
HIP 116476 |
26.15 |
| 2026-04-15 00:00 |
23:38:38.56 |
-54:54:26.0 |
HIP 116476 |
27.25 |
| 2026-04-15 12:00 |
23:38:47.16 |
-54:54:36.0 |
HIP 116476 |
28.37 |
| 2026-04-16 00:00 |
23:38:55.72 |
-54:54:46.8 |
HIP 116476 |
29.49 |