メタデータ
| 項目 |
値 |
| Designation |
C/2019 H1 (NEOWISE) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-04-27T17:40:42.101760Z |
| Orbit solution date (soln_date, UTC) |
2022-06-20T23:12:33Z |
| Obs used |
165 |
| NEO |
- |
| M1 |
16.900 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-04-18T21:12:57.600000Z |
| 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) |
2019-05-16.0000000 |
| e |
0.99219409 |
| q (au) |
1.844784 |
| a (au) |
236.331687 |
| i (deg) |
104.580185 |
| Ω (om, deg) |
269.186008 |
| ω (w, deg) |
19.282675 |
| M (ma, deg) |
0.004955 |
等級
散乱 + 全体線形
$$
M_a = (17.164 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
17.164 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-0.518 |
| 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) |
| 2026-09-20 00:00 |
06:31:23.21 |
+38:29:13.5 |
HIP 30974 |
32.60 |
| 2026-09-20 12:00 |
06:31:24.09 |
+38:29:27.8 |
HIP 30974 |
32.48 |
| 2026-09-21 00:00 |
06:31:24.91 |
+38:29:42.2 |
HIP 30974 |
32.34 |
| 2026-09-21 12:00 |
06:31:25.66 |
+38:29:56.7 |
HIP 30974 |
32.20 |
| 2026-09-22 00:00 |
06:31:26.35 |
+38:30:11.3 |
HIP 30974 |
32.06 |
| 2026-09-22 12:00 |
06:31:26.97 |
+38:30:26.0 |
HIP 30974 |
31.91 |
| 2026-09-23 00:00 |
06:31:27.53 |
+38:30:40.7 |
HIP 30974 |
31.75 |
| 2026-09-23 12:00 |
06:31:28.02 |
+38:30:55.5 |
HIP 30974 |
31.59 |
| 2026-09-24 00:00 |
06:31:28.45 |
+38:31:10.4 |
HIP 30974 |
31.42 |
| 2026-09-24 12:00 |
06:31:28.82 |
+38:31:25.4 |
HIP 30974 |
31.25 |
| 2026-09-25 00:00 |
06:31:29.12 |
+38:31:40.4 |
HIP 30974 |
31.07 |
| 2026-09-25 12:00 |
06:31:29.35 |
+38:31:55.5 |
HIP 30974 |
30.88 |
| 2026-09-26 00:00 |
06:31:29.52 |
+38:32:10.7 |
HIP 30974 |
30.69 |
| 2026-09-26 12:00 |
06:31:29.62 |
+38:32:25.9 |
HIP 30974 |
30.48 |
| 2026-09-27 00:00 |
06:31:29.66 |
+38:32:41.2 |
HIP 30974 |
30.27 |
| 2026-09-27 12:00 |
06:31:29.63 |
+38:32:56.6 |
HIP 30974 |
30.06 |
| 2026-09-28 00:00 |
06:31:29.54 |
+38:33:12.0 |
HIP 30974 |
29.83 |
| 2026-09-28 12:00 |
06:31:29.38 |
+38:33:27.5 |
HIP 30974 |
29.60 |
| 2026-09-29 00:00 |
06:31:29.15 |
+38:33:43.0 |
HIP 30974 |
29.36 |
| 2026-09-29 12:00 |
06:31:28.86 |
+38:33:58.6 |
HIP 30974 |
29.12 |
| 2026-09-30 00:00 |
06:31:28.50 |
+38:34:14.3 |
HIP 30974 |
28.86 |
| 2026-09-30 12:00 |
06:31:28.08 |
+38:34:30.0 |
HIP 30974 |
28.60 |
| 2026-10-01 00:00 |
06:31:27.59 |
+38:34:45.7 |
HIP 30974 |
28.33 |
| 2026-10-01 12:00 |
06:31:27.03 |
+38:35:01.5 |
HIP 30974 |
28.05 |
| 2026-10-02 00:00 |
06:31:26.40 |
+38:35:17.4 |
HIP 30974 |
27.77 |
| 2026-10-02 12:00 |
06:31:25.71 |
+38:35:33.3 |
HIP 30974 |
27.47 |
| 2026-10-03 00:00 |
06:31:24.95 |
+38:35:49.2 |
HIP 30974 |
27.17 |
| 2026-10-03 12:00 |
06:31:24.13 |
+38:36:05.2 |
HIP 30974 |
26.86 |
| 2026-10-04 00:00 |
06:31:23.23 |
+38:36:21.2 |
HIP 30974 |
26.54 |
| 2026-10-04 12:00 |
06:31:22.27 |
+38:36:37.3 |
HIP 30974 |
26.21 |
| 2026-10-05 00:00 |
06:31:21.25 |
+38:36:53.4 |
HIP 30974 |
25.88 |
| 2026-10-05 12:00 |
06:31:20.15 |
+38:37:09.5 |
HIP 30974 |
25.54 |
| 2026-10-06 00:00 |
06:31:18.99 |
+38:37:25.7 |
HIP 30974 |
25.18 |
| 2026-10-06 12:00 |
06:31:17.76 |
+38:37:41.9 |
HIP 30974 |
24.82 |
| 2026-10-07 00:00 |
06:31:16.46 |
+38:37:58.1 |
HIP 30974 |
24.46 |
| 2026-10-07 12:00 |
06:31:15.09 |
+38:38:14.4 |
HIP 30974 |
24.08 |
| 2026-10-08 00:00 |
06:31:13.66 |
+38:38:30.7 |
HIP 30974 |
23.70 |
| 2026-10-08 12:00 |
06:31:12.15 |
+38:38:47.0 |
HIP 30974 |
23.31 |
| 2026-10-09 00:00 |
06:31:10.58 |
+38:39:03.3 |
HIP 30974 |
22.91 |
| 2026-10-09 12:00 |
06:31:08.94 |
+38:39:19.7 |
HIP 30974 |
22.50 |
| 2026-10-10 00:00 |
06:31:07.24 |
+38:39:36.0 |
HIP 30974 |
22.09 |
| 2026-10-10 12:00 |
06:31:05.46 |
+38:39:52.4 |
HIP 30974 |
21.67 |
| 2026-10-11 00:00 |
06:31:03.62 |
+38:40:08.8 |
HIP 30974 |
21.25 |