メタデータ
| 項目 |
値 |
| Designation |
C/2019 L2 (NEOWISE) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-04-02T01:58:42.522240Z |
| Orbit solution date (soln_date, UTC) |
2022-07-19T02:26:14Z |
| Obs used |
117 |
| NEO |
- |
| M1 |
10.400 |
| K1 |
27.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-06-11T18:48:21.312000Z |
| Discovery magnitude (MPC) |
18.00 R |
| Discovery observatory (MPC) |
C51 · WISE |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-07-05.0000000 |
| e |
0.93676409 |
| q (au) |
1.621540 |
| a (au) |
25.642708 |
| i (deg) |
152.187378 |
| Ω (om, deg) |
12.534296 |
| ω (w, deg) |
18.816880 |
| M (ma, deg) |
0.712861 |
等級
散乱 + 全体線形
$$
M_a = (13.141 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.141 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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) |
| 2026-05-12 00:00 |
13:20:02.31 |
-03:11:13.8 |
HIP 65081 |
10.95 |
| 2026-05-12 12:00 |
13:19:55.91 |
-03:10:45.4 |
HIP 65081 |
11.43 |
| 2026-05-13 00:00 |
13:19:49.55 |
-03:10:17.4 |
HIP 65081 |
12.12 |
| 2026-05-13 12:00 |
13:19:43.23 |
-03:09:49.6 |
HIP 64965 |
12.78 |
| 2026-05-14 00:00 |
13:19:36.93 |
-03:09:22.1 |
HIP 64965 |
11.17 |
| 2026-05-14 12:00 |
13:19:30.67 |
-03:08:54.8 |
HIP 64965 |
9.58 |
| 2026-05-15 00:00 |
13:19:24.44 |
-03:08:27.8 |
HIP 64965 |
8.01 |
| 2026-05-15 12:00 |
13:19:18.25 |
-03:08:01.1 |
HIP 64965 |
6.47 |
| 2026-05-16 00:00 |
13:19:12.10 |
-03:07:34.7 |
HIP 64965 |
4.99 |
| 2026-05-16 12:00 |
13:19:05.98 |
-03:07:08.5 |
HIP 64965 |
3.62 |
| 2026-05-17 00:00 |
13:18:59.89 |
-03:06:42.6 |
HIP 64965 |
2.53 |
| 2026-05-17 12:00 |
13:18:53.85 |
-03:06:16.9 |
HIP 64965 |
2.16 |
| 2026-05-18 00:00 |
13:18:47.84 |
-03:05:51.6 |
HIP 64965 |
2.80 |
| 2026-05-18 12:00 |
13:18:41.86 |
-03:05:26.5 |
HIP 64965 |
3.97 |
| 2026-05-19 00:00 |
13:18:35.93 |
-03:05:01.7 |
HIP 64965 |
5.33 |
| 2026-05-19 12:00 |
13:18:30.03 |
-03:04:37.2 |
HIP 64965 |
6.76 |
| 2026-05-20 00:00 |
13:18:24.18 |
-03:04:13.0 |
HIP 64965 |
8.22 |
| 2026-05-20 12:00 |
13:18:18.36 |
-03:03:49.1 |
HIP 64965 |
9.68 |
| 2026-05-21 00:00 |
13:18:12.58 |
-03:03:25.4 |
HIP 64965 |
11.14 |
| 2026-05-21 12:00 |
13:18:06.84 |
-03:03:02.1 |
HIP 64965 |
12.61 |
| 2026-05-22 00:00 |
13:18:01.14 |
-03:02:39.0 |
HIP 64965 |
14.06 |
| 2026-05-22 12:00 |
13:17:55.48 |
-03:02:16.3 |
HIP 64965 |
15.51 |
| 2026-05-23 00:00 |
13:17:49.86 |
-03:01:53.8 |
HIP 64965 |
16.95 |
| 2026-05-23 12:00 |
13:17:44.29 |
-03:01:31.6 |
HIP 64965 |
18.38 |
| 2026-05-24 00:00 |
13:17:38.75 |
-03:01:09.8 |
HIP 64965 |
19.80 |
| 2026-05-24 12:00 |
13:17:33.26 |
-03:00:48.2 |
HIP 64965 |
21.21 |
| 2026-05-25 00:00 |
13:17:27.81 |
-03:00:26.9 |
HIP 64965 |
22.62 |
| 2026-05-25 12:00 |
13:17:22.40 |
-03:00:05.9 |
HIP 64721 |
22.20 |
| 2026-05-26 00:00 |
13:17:17.03 |
-02:59:45.2 |
HIP 64721 |
21.04 |
| 2026-05-26 12:00 |
13:17:11.71 |
-02:59:24.9 |
HIP 64721 |
19.92 |
| 2026-05-27 00:00 |
13:17:06.43 |
-02:59:04.8 |
HIP 64721 |
18.83 |
| 2026-05-27 12:00 |
13:17:01.19 |
-02:58:45.0 |
HIP 64721 |
17.79 |
| 2026-05-28 00:00 |
13:16:56.00 |
-02:58:25.6 |
HIP 64721 |
16.80 |
| 2026-05-28 12:00 |
13:16:50.85 |
-02:58:06.4 |
HIP 64721 |
15.87 |
| 2026-05-29 00:00 |
13:16:45.75 |
-02:57:47.6 |
HIP 64721 |
15.00 |
| 2026-05-29 12:00 |
13:16:40.69 |
-02:57:29.1 |
HIP 64721 |
14.21 |
| 2026-05-30 00:00 |
13:16:35.67 |
-02:57:10.8 |
HIP 64721 |
13.50 |
| 2026-05-30 12:00 |
13:16:30.70 |
-02:56:52.9 |
HIP 64721 |
12.89 |
| 2026-05-31 00:00 |
13:16:25.78 |
-02:56:35.3 |
HIP 64721 |
12.37 |
| 2026-05-31 12:00 |
13:16:20.90 |
-02:56:18.0 |
HIP 64721 |
11.97 |
| 2026-06-01 00:00 |
13:16:16.06 |
-02:56:01.1 |
HIP 64721 |
11.69 |
| 2026-06-01 12:00 |
13:16:11.28 |
-02:55:44.4 |
HIP 64721 |
11.54 |
| 2026-06-02 00:00 |
13:16:06.54 |
-02:55:28.0 |
HIP 64721 |
11.51 |