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) |
| 2026-09-20 00:00 |
22:08:18.39 |
+55:56:44.6 |
HIP 109249 |
3.75 |
| 2026-09-20 12:00 |
22:08:04.29 |
+55:55:29.3 |
HIP 109249 |
1.44 |
| 2026-09-21 00:00 |
22:07:50.28 |
+55:54:13.2 |
HIP 109249 |
1.01 |
| 2026-09-21 12:00 |
22:07:36.33 |
+55:52:56.1 |
HIP 109249 |
3.30 |
| 2026-09-22 00:00 |
22:07:22.46 |
+55:51:38.2 |
HIP 109249 |
5.63 |
| 2026-09-22 12:00 |
22:07:08.67 |
+55:50:19.4 |
HIP 109225 |
7.06 |
| 2026-09-23 00:00 |
22:06:54.96 |
+55:48:59.8 |
HIP 109225 |
7.55 |
| 2026-09-23 12:00 |
22:06:41.32 |
+55:47:39.3 |
HIP 109225 |
8.65 |
| 2026-09-24 00:00 |
22:06:27.77 |
+55:46:18.0 |
HIP 109225 |
10.17 |
| 2026-09-24 12:00 |
22:06:14.29 |
+55:44:55.8 |
HIP 109225 |
11.95 |
| 2026-09-25 00:00 |
22:06:00.90 |
+55:43:32.8 |
HIP 109225 |
13.88 |
| 2026-09-25 12:00 |
22:05:47.59 |
+55:42:09.0 |
HIP 109225 |
15.92 |
| 2026-09-26 00:00 |
22:05:34.36 |
+55:40:44.4 |
HIP 109225 |
18.02 |
| 2026-09-26 12:00 |
22:05:21.21 |
+55:39:19.0 |
HIP 108921 |
17.52 |
| 2026-09-27 00:00 |
22:05:08.16 |
+55:37:52.8 |
HIP 108889 |
17.17 |
| 2026-09-27 12:00 |
22:04:55.18 |
+55:36:25.8 |
HIP 108889 |
16.58 |
| 2026-09-28 00:00 |
22:04:42.30 |
+55:34:58.0 |
HIP 108889 |
16.32 |
| 2026-09-28 12:00 |
22:04:29.50 |
+55:33:29.5 |
HIP 108889 |
16.41 |
| 2026-09-29 00:00 |
22:04:16.79 |
+55:32:00.2 |
HIP 108889 |
16.84 |
| 2026-09-29 12:00 |
22:04:04.17 |
+55:30:30.1 |
HIP 108889 |
17.59 |
| 2026-09-30 00:00 |
22:03:51.65 |
+55:28:59.3 |
HIP 108889 |
18.61 |
| 2026-09-30 12:00 |
22:03:39.21 |
+55:27:27.8 |
HIP 108889 |
19.87 |
| 2026-10-01 00:00 |
22:03:26.87 |
+55:25:55.5 |
HIP 108889 |
21.32 |
| 2026-10-01 12:00 |
22:03:14.62 |
+55:24:22.5 |
HIP 108889 |
22.93 |
| 2026-10-02 00:00 |
22:03:02.46 |
+55:22:48.8 |
HIP 108889 |
24.66 |
| 2026-10-02 12:00 |
22:02:50.40 |
+55:21:14.3 |
HIP 108889 |
26.49 |
| 2026-10-03 00:00 |
22:02:38.44 |
+55:19:39.2 |
HIP 108605 |
25.00 |
| 2026-10-03 12:00 |
22:02:26.57 |
+55:18:03.4 |
HIP 108605 |
22.77 |
| 2026-10-04 00:00 |
22:02:14.80 |
+55:16:26.9 |
HIP 108605 |
20.56 |
| 2026-10-04 12:00 |
22:02:03.12 |
+55:14:49.7 |
HIP 108605 |
18.39 |
| 2026-10-05 00:00 |
22:01:51.55 |
+55:13:11.9 |
HIP 108605 |
16.26 |
| 2026-10-05 12:00 |
22:01:40.08 |
+55:11:33.4 |
HIP 108605 |
14.21 |
| 2026-10-06 00:00 |
22:01:28.71 |
+55:09:54.2 |
HIP 108605 |
12.26 |
| 2026-10-06 12:00 |
22:01:17.44 |
+55:08:14.5 |
HIP 108605 |
10.47 |
| 2026-10-07 00:00 |
22:01:06.27 |
+55:06:34.0 |
HIP 108605 |
8.94 |
| 2026-10-07 12:00 |
22:00:55.21 |
+55:04:53.0 |
HIP 108605 |
7.83 |
| 2026-10-08 00:00 |
22:00:44.25 |
+55:03:11.4 |
HIP 108607 |
6.01 |
| 2026-10-08 12:00 |
22:00:33.39 |
+55:01:29.2 |
HIP 108607 |
4.13 |
| 2026-10-09 00:00 |
22:00:22.64 |
+54:59:46.4 |
HIP 108607 |
2.94 |
| 2026-10-09 12:00 |
22:00:12.00 |
+54:58:03.0 |
HIP 108607 |
3.31 |
| 2026-10-10 00:00 |
22:00:01.46 |
+54:56:19.0 |
HIP 108607 |
4.89 |
| 2026-10-10 12:00 |
21:59:51.03 |
+54:54:34.5 |
HIP 108607 |
6.90 |
| 2026-10-11 00:00 |
21:59:40.71 |
+54:52:49.4 |
HIP 108607 |
9.04 |