メタデータ
| 項目 |
値 |
| Designation |
C/2021 B3 (NEOWISE) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-03-10T21:53:20.584320Z |
| Orbit solution date (soln_date, UTC) |
2021-07-01T22:12:56Z |
| Obs used |
84 |
| NEO |
- |
| M1 |
13.900 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-01-22T05:58:17.184000Z |
| Discovery magnitude (MPC) |
19.00 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) |
2021-02-16.0000000 |
| e |
0.93819965 |
| q (au) |
2.160159 |
| a (au) |
34.953837 |
| i (deg) |
119.489804 |
| Ω (om, deg) |
67.284845 |
| ω (w, deg) |
293.559147 |
| M (ma, deg) |
359.890724 |
等級
散乱 + 全体線形
$$
M_a = (11.234 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.234 |
| 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) |
| 2026-07-29 00:00 |
22:35:29.85 |
+56:32:03.0 |
HIP 111363 |
15.05 |
| 2026-07-29 12:00 |
22:35:15.80 |
+56:32:38.7 |
HIP 111363 |
13.14 |
| 2026-07-30 00:00 |
22:35:01.67 |
+56:33:13.4 |
HIP 111363 |
11.27 |
| 2026-07-30 12:00 |
22:34:47.48 |
+56:33:47.1 |
HIP 111363 |
9.46 |
| 2026-07-31 00:00 |
22:34:33.22 |
+56:34:19.8 |
HIP 111363 |
7.73 |
| 2026-07-31 12:00 |
22:34:18.89 |
+56:34:51.6 |
HIP 111362 |
5.89 |
| 2026-08-01 00:00 |
22:34:04.50 |
+56:35:22.3 |
HIP 111362 |
3.91 |
| 2026-08-01 12:00 |
22:33:50.03 |
+56:35:52.1 |
HIP 111362 |
2.07 |
| 2026-08-02 00:00 |
22:33:35.51 |
+56:36:20.8 |
HIP 111362 |
1.33 |
| 2026-08-02 12:00 |
22:33:20.92 |
+56:36:48.5 |
HIP 111362 |
2.78 |
| 2026-08-03 00:00 |
22:33:06.27 |
+56:37:15.2 |
HIP 111362 |
4.72 |
| 2026-08-03 12:00 |
22:32:51.56 |
+56:37:40.9 |
HIP 111362 |
6.74 |
| 2026-08-04 00:00 |
22:32:36.79 |
+56:38:05.6 |
HIP 111362 |
8.79 |
| 2026-08-04 12:00 |
22:32:21.96 |
+56:38:29.2 |
HIP 111362 |
10.86 |
| 2026-08-05 00:00 |
22:32:07.07 |
+56:38:51.8 |
HIP 111362 |
12.93 |
| 2026-08-05 12:00 |
22:31:52.13 |
+56:39:13.4 |
HIP 111362 |
15.01 |
| 2026-08-06 00:00 |
22:31:37.13 |
+56:39:33.9 |
HIP 111060 |
15.94 |
| 2026-08-06 12:00 |
22:31:22.08 |
+56:39:53.4 |
HIP 111060 |
13.98 |
| 2026-08-07 00:00 |
22:31:06.97 |
+56:40:11.8 |
HIP 111060 |
12.06 |
| 2026-08-07 12:00 |
22:30:51.82 |
+56:40:29.2 |
HIP 111060 |
10.23 |
| 2026-08-08 00:00 |
22:30:36.61 |
+56:40:45.5 |
HIP 111060 |
8.53 |
| 2026-08-08 12:00 |
22:30:21.35 |
+56:41:00.8 |
HIP 111060 |
7.06 |
| 2026-08-09 00:00 |
22:30:06.05 |
+56:41:15.0 |
HIP 111060 |
5.99 |
| 2026-08-09 12:00 |
22:29:50.70 |
+56:41:28.1 |
HIP 111060 |
5.59 |
| 2026-08-10 00:00 |
22:29:35.31 |
+56:41:40.2 |
HIP 111060 |
5.97 |
| 2026-08-10 12:00 |
22:29:19.87 |
+56:41:51.1 |
HIP 110967 |
6.49 |
| 2026-08-11 00:00 |
22:29:04.39 |
+56:42:01.0 |
HIP 110967 |
5.92 |
| 2026-08-11 12:00 |
22:28:48.87 |
+56:42:09.8 |
HIP 110967 |
6.07 |
| 2026-08-12 00:00 |
22:28:33.31 |
+56:42:17.6 |
HIP 110967 |
6.90 |
| 2026-08-12 12:00 |
22:28:17.71 |
+56:42:24.2 |
HIP 110967 |
8.21 |
| 2026-08-13 00:00 |
22:28:02.08 |
+56:42:29.8 |
HIP 110967 |
9.81 |
| 2026-08-13 12:00 |
22:27:46.41 |
+56:42:34.2 |
HIP 110967 |
11.58 |
| 2026-08-14 00:00 |
22:27:30.71 |
+56:42:37.6 |
HIP 110967 |
13.46 |
| 2026-08-14 12:00 |
22:27:14.97 |
+56:42:39.8 |
HIP 110967 |
15.41 |
| 2026-08-15 00:00 |
22:26:59.21 |
+56:42:41.0 |
HIP 110807 |
16.67 |
| 2026-08-15 12:00 |
22:26:43.42 |
+56:42:41.1 |
HIP 110648 |
14.87 |
| 2026-08-16 00:00 |
22:26:27.60 |
+56:42:40.1 |
HIP 110648 |
12.70 |
| 2026-08-16 12:00 |
22:26:11.75 |
+56:42:37.9 |
HIP 110648 |
10.52 |
| 2026-08-17 00:00 |
22:25:55.88 |
+56:42:34.7 |
HIP 110648 |
8.34 |
| 2026-08-17 12:00 |
22:25:39.99 |
+56:42:30.3 |
HIP 110648 |
6.16 |
| 2026-08-18 00:00 |
22:25:24.07 |
+56:42:24.9 |
HIP 110648 |
3.98 |
| 2026-08-18 12:00 |
22:25:08.13 |
+56:42:18.4 |
HIP 110648 |
1.82 |
| 2026-08-19 00:00 |
22:24:52.18 |
+56:42:10.7 |
HIP 110648 |
0.59 |