メタデータ
| 項目 |
値 |
| Designation |
C/2021 B2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-05-04T06:39:22.443840Z |
| Orbit solution date (soln_date, UTC) |
2022-06-07T21:45:07Z |
| Obs used |
93 |
| NEO |
- |
| M1 |
12.200 |
| K1 |
12.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-01-17T05:33:50.803200Z |
| Discovery magnitude (MPC) |
19.96 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-04-03.0000000 |
| e |
0.99252519 |
| q (au) |
2.513062 |
| a (au) |
336.204150 |
| i (deg) |
38.094193 |
| Ω (om, deg) |
120.555561 |
| ω (w, deg) |
334.974070 |
| M (ma, deg) |
359.994999 |
等級
散乱 + 全体線形
$$
M_a = (10.993 + 5.530\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.993 |
| n |
5.530 |
| gf |
0.921 |
| gb |
-0.787 |
| k |
0.997 |
| δ90 |
6.444 |
| 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 |
15:41:16.82 |
+16:13:49.7 |
HIP 76810 |
13.06 |
| 2026-09-20 12:00 |
15:41:21.89 |
+16:12:34.4 |
HIP 76810 |
12.37 |
| 2026-09-21 00:00 |
15:41:27.01 |
+16:11:19.3 |
HIP 76810 |
11.91 |
| 2026-09-21 12:00 |
15:41:32.18 |
+16:10:04.4 |
HIP 76810 |
11.71 |
| 2026-09-22 00:00 |
15:41:37.40 |
+16:08:49.7 |
HIP 76810 |
11.78 |
| 2026-09-22 12:00 |
15:41:42.66 |
+16:07:35.2 |
HIP 76810 |
12.12 |
| 2026-09-23 00:00 |
15:41:47.98 |
+16:06:20.9 |
HIP 76810 |
12.72 |
| 2026-09-23 12:00 |
15:41:53.35 |
+16:05:06.9 |
HIP 76810 |
13.53 |
| 2026-09-24 00:00 |
15:41:58.76 |
+16:03:53.0 |
HIP 76810 |
14.54 |
| 2026-09-24 12:00 |
15:42:04.22 |
+16:02:39.4 |
HIP 76810 |
15.70 |
| 2026-09-25 00:00 |
15:42:09.74 |
+16:01:26.1 |
HIP 76810 |
16.98 |
| 2026-09-25 12:00 |
15:42:15.29 |
+16:00:12.9 |
HIP 76810 |
18.36 |
| 2026-09-26 00:00 |
15:42:20.90 |
+15:59:00.0 |
HIP 76810 |
19.82 |
| 2026-09-26 12:00 |
15:42:26.55 |
+15:57:47.4 |
HIP 76810 |
21.34 |
| 2026-09-27 00:00 |
15:42:32.25 |
+15:56:34.9 |
HIP 76810 |
22.92 |
| 2026-09-27 12:00 |
15:42:37.99 |
+15:55:22.8 |
HIP 76810 |
24.54 |
| 2026-09-28 00:00 |
15:42:43.78 |
+15:54:10.8 |
HIP 76810 |
26.20 |
| 2026-09-28 12:00 |
15:42:49.62 |
+15:52:59.2 |
HIP 77050 |
25.78 |
| 2026-09-29 00:00 |
15:42:55.50 |
+15:51:47.7 |
HIP 77050 |
23.95 |
| 2026-09-29 12:00 |
15:43:01.43 |
+15:50:36.6 |
HIP 77050 |
22.12 |
| 2026-09-30 00:00 |
15:43:07.40 |
+15:49:25.7 |
HIP 77050 |
20.29 |
| 2026-09-30 12:00 |
15:43:13.41 |
+15:48:15.0 |
HIP 77050 |
18.47 |
| 2026-10-01 00:00 |
15:43:19.47 |
+15:47:04.7 |
HIP 77050 |
16.65 |
| 2026-10-01 12:00 |
15:43:25.57 |
+15:45:54.6 |
HIP 77050 |
14.84 |
| 2026-10-02 00:00 |
15:43:31.72 |
+15:44:44.7 |
HIP 77050 |
13.06 |
| 2026-10-02 12:00 |
15:43:37.91 |
+15:43:35.2 |
HIP 77050 |
11.30 |
| 2026-10-03 00:00 |
15:43:44.14 |
+15:42:25.9 |
HIP 77050 |
9.58 |
| 2026-10-03 12:00 |
15:43:50.41 |
+15:41:17.0 |
HIP 77050 |
7.96 |
| 2026-10-04 00:00 |
15:43:56.73 |
+15:40:08.3 |
HIP 77050 |
6.48 |
| 2026-10-04 12:00 |
15:44:03.09 |
+15:39:00.0 |
HIP 77050 |
5.29 |
| 2026-10-05 00:00 |
15:44:09.49 |
+15:37:51.8 |
HIP 77050 |
4.62 |
| 2026-10-05 12:00 |
15:44:15.93 |
+15:36:44.0 |
HIP 77050 |
4.71 |
| 2026-10-06 00:00 |
15:44:22.41 |
+15:35:36.5 |
HIP 77050 |
5.52 |
| 2026-10-06 12:00 |
15:44:28.93 |
+15:34:29.4 |
HIP 77050 |
6.80 |
| 2026-10-07 00:00 |
15:44:35.49 |
+15:33:22.5 |
HIP 77050 |
8.35 |
| 2026-10-07 12:00 |
15:44:42.09 |
+15:32:16.0 |
HIP 77050 |
10.04 |
| 2026-10-08 00:00 |
15:44:48.73 |
+15:31:09.7 |
HIP 77050 |
11.81 |
| 2026-10-08 12:00 |
15:44:55.41 |
+15:30:03.8 |
HIP 77050 |
13.64 |
| 2026-10-09 00:00 |
15:45:02.12 |
+15:28:58.3 |
HIP 77083 |
14.67 |
| 2026-10-09 12:00 |
15:45:08.88 |
+15:27:53.0 |
HIP 77083 |
15.06 |
| 2026-10-10 00:00 |
15:45:15.67 |
+15:26:48.1 |
HIP 77233 |
13.47 |
| 2026-10-10 12:00 |
15:45:22.50 |
+15:25:43.5 |
HIP 77233 |
11.75 |
| 2026-10-11 00:00 |
15:45:29.37 |
+15:24:39.3 |
HIP 77233 |
10.11 |