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) |
| 2026-07-29 00:00 |
15:37:58.04 |
+18:30:35.5 |
HIP 76408 |
30.50 |
| 2026-07-29 12:00 |
15:37:56.49 |
+18:29:24.9 |
HIP 76408 |
30.99 |
| 2026-07-30 00:00 |
15:37:55.01 |
+18:28:14.0 |
HIP 76408 |
31.53 |
| 2026-07-30 12:00 |
15:37:53.59 |
+18:27:02.8 |
HIP 76408 |
32.13 |
| 2026-07-31 00:00 |
15:37:52.24 |
+18:25:51.3 |
HIP 76408 |
32.78 |
| 2026-07-31 12:00 |
15:37:50.96 |
+18:24:39.5 |
HIP 76408 |
33.47 |
| 2026-08-01 00:00 |
15:37:49.75 |
+18:23:27.4 |
HIP 76408 |
34.21 |
| 2026-08-01 12:00 |
15:37:48.60 |
+18:22:15.1 |
HIP 76408 |
35.00 |
| 2026-08-02 00:00 |
15:37:47.52 |
+18:21:02.5 |
HIP 76408 |
35.81 |
| 2026-08-02 12:00 |
15:37:46.50 |
+18:19:49.6 |
HIP 76408 |
36.67 |
| 2026-08-03 00:00 |
15:37:45.56 |
+18:18:36.5 |
HIP 76408 |
37.56 |
| 2026-08-03 12:00 |
15:37:44.68 |
+18:17:23.0 |
HIP 76408 |
38.48 |
| 2026-08-04 00:00 |
15:37:43.87 |
+18:16:09.4 |
HIP 76408 |
39.43 |
| 2026-08-04 12:00 |
15:37:43.12 |
+18:14:55.5 |
HIP 76408 |
40.41 |
| 2026-08-05 00:00 |
15:37:42.44 |
+18:13:41.3 |
HIP 76408 |
41.41 |
| 2026-08-05 12:00 |
15:37:41.83 |
+18:12:26.9 |
HIP 76408 |
42.44 |
| 2026-08-06 00:00 |
15:37:41.29 |
+18:11:12.3 |
HIP 76408 |
43.48 |
| 2026-08-06 12:00 |
15:37:40.82 |
+18:09:57.5 |
HIP 76337 |
43.11 |
| 2026-08-07 00:00 |
15:37:40.41 |
+18:08:42.4 |
HIP 76337 |
42.16 |
| 2026-08-07 12:00 |
15:37:40.07 |
+18:07:27.1 |
HIP 76337 |
41.24 |
| 2026-08-08 00:00 |
15:37:39.80 |
+18:06:11.6 |
HIP 76337 |
40.34 |
| 2026-08-08 12:00 |
15:37:39.59 |
+18:04:55.9 |
HIP 76337 |
39.48 |
| 2026-08-09 00:00 |
15:37:39.46 |
+18:03:39.9 |
HIP 76337 |
38.65 |
| 2026-08-09 12:00 |
15:37:39.39 |
+18:02:23.8 |
HIP 76337 |
37.85 |
| 2026-08-10 00:00 |
15:37:39.39 |
+18:01:07.5 |
HIP 76337 |
37.09 |
| 2026-08-10 12:00 |
15:37:39.45 |
+17:59:51.0 |
HIP 76337 |
36.37 |
| 2026-08-11 00:00 |
15:37:39.59 |
+17:58:34.3 |
HIP 76337 |
35.69 |
| 2026-08-11 12:00 |
15:37:39.79 |
+17:57:17.4 |
HIP 76337 |
35.06 |
| 2026-08-12 00:00 |
15:37:40.06 |
+17:56:00.4 |
HIP 76337 |
34.48 |
| 2026-08-12 12:00 |
15:37:40.40 |
+17:54:43.1 |
HIP 76337 |
33.95 |
| 2026-08-13 00:00 |
15:37:40.80 |
+17:53:25.8 |
HIP 76337 |
33.47 |
| 2026-08-13 12:00 |
15:37:41.27 |
+17:52:08.2 |
HIP 76337 |
33.05 |
| 2026-08-14 00:00 |
15:37:41.81 |
+17:50:50.6 |
HIP 76337 |
32.70 |
| 2026-08-14 12:00 |
15:37:42.42 |
+17:49:32.7 |
HIP 76337 |
32.40 |
| 2026-08-15 00:00 |
15:37:43.09 |
+17:48:14.8 |
HIP 76337 |
32.17 |
| 2026-08-15 12:00 |
15:37:43.83 |
+17:46:56.7 |
HIP 76337 |
32.01 |
| 2026-08-16 00:00 |
15:37:44.64 |
+17:45:38.4 |
HIP 76548 |
31.04 |
| 2026-08-16 12:00 |
15:37:45.51 |
+17:44:20.1 |
HIP 76548 |
29.72 |
| 2026-08-17 00:00 |
15:37:46.45 |
+17:43:01.6 |
HIP 76548 |
28.39 |
| 2026-08-17 12:00 |
15:37:47.46 |
+17:41:43.0 |
HIP 76548 |
27.06 |
| 2026-08-18 00:00 |
15:37:48.53 |
+17:40:24.4 |
HIP 76548 |
25.73 |
| 2026-08-18 12:00 |
15:37:49.67 |
+17:39:05.6 |
HIP 76548 |
24.40 |
| 2026-08-19 00:00 |
15:37:50.88 |
+17:37:46.7 |
HIP 76548 |
23.06 |