メタデータ
| 項目 |
値 |
| Designation |
P/2021 C2 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-02-24T15:22:00.105600Z |
| Orbit solution date (soln_date, UTC) |
2021-10-18T22:42:46Z |
| Obs used |
55 |
| NEO |
- |
| M1 |
11.400 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-02-12T12:41:22.185600Z |
| Discovery magnitude (MPC) |
22.16 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) |
2021-03-19.0000000 |
| e |
0.48743656 |
| q (au) |
4.890288 |
| a (au) |
9.540845 |
| i (deg) |
21.926912 |
| Ω (om, deg) |
66.498296 |
| ω (w, deg) |
78.823510 |
| M (ma, deg) |
0.747808 |
等級
散乱 + 全体線形
$$
M_a = (13.932 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.932 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-0.569 |
| 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) |
| 2026-05-12 00:00 |
17:51:11.62 |
-31:10:40.1 |
HIP 87364 |
12.55 |
| 2026-05-12 12:00 |
17:51:03.26 |
-31:11:13.9 |
HIP 87364 |
13.03 |
| 2026-05-13 00:00 |
17:50:54.82 |
-31:11:47.4 |
HIP 87364 |
13.75 |
| 2026-05-13 12:00 |
17:50:46.29 |
-31:12:20.8 |
HIP 87364 |
14.69 |
| 2026-05-14 00:00 |
17:50:37.67 |
-31:12:53.9 |
HIP 87364 |
15.80 |
| 2026-05-14 12:00 |
17:50:28.97 |
-31:13:26.8 |
HIP 87364 |
17.07 |
| 2026-05-15 00:00 |
17:50:20.18 |
-31:13:59.5 |
HIP 87364 |
18.46 |
| 2026-05-15 12:00 |
17:50:11.32 |
-31:14:32.0 |
HIP 87364 |
19.95 |
| 2026-05-16 00:00 |
17:50:02.37 |
-31:15:04.3 |
HIP 87364 |
21.53 |
| 2026-05-16 12:00 |
17:49:53.34 |
-31:15:36.3 |
HIP 87364 |
23.17 |
| 2026-05-17 00:00 |
17:49:44.23 |
-31:16:08.1 |
HIP 87364 |
24.89 |
| 2026-05-17 12:00 |
17:49:35.04 |
-31:16:39.7 |
HIP 87220 |
26.06 |
| 2026-05-18 00:00 |
17:49:25.77 |
-31:17:11.0 |
HIP 87220 |
25.22 |
| 2026-05-18 12:00 |
17:49:16.43 |
-31:17:42.2 |
HIP 87220 |
24.52 |
| 2026-05-19 00:00 |
17:49:07.02 |
-31:18:13.0 |
HIP 87220 |
23.99 |
| 2026-05-19 12:00 |
17:48:57.53 |
-31:18:43.7 |
HIP 87220 |
23.63 |
| 2026-05-20 00:00 |
17:48:47.97 |
-31:19:14.0 |
HIP 87220 |
23.45 |
| 2026-05-20 12:00 |
17:48:38.34 |
-31:19:44.2 |
HIP 87220 |
23.48 |
| 2026-05-21 00:00 |
17:48:28.64 |
-31:20:14.1 |
HIP 87220 |
23.70 |
| 2026-05-21 12:00 |
17:48:18.87 |
-31:20:43.7 |
HIP 87022 |
23.23 |
| 2026-05-22 00:00 |
17:48:09.03 |
-31:21:13.1 |
HIP 87022 |
21.29 |
| 2026-05-22 12:00 |
17:47:59.13 |
-31:21:42.2 |
HIP 87022 |
19.38 |
| 2026-05-23 00:00 |
17:47:49.16 |
-31:22:11.1 |
HIP 87022 |
17.53 |
| 2026-05-23 12:00 |
17:47:39.13 |
-31:22:39.7 |
HIP 87022 |
15.76 |
| 2026-05-24 00:00 |
17:47:29.04 |
-31:23:08.1 |
HIP 87022 |
14.10 |
| 2026-05-24 12:00 |
17:47:18.88 |
-31:23:36.1 |
HIP 87022 |
12.61 |
| 2026-05-25 00:00 |
17:47:08.67 |
-31:24:04.0 |
HIP 87022 |
11.36 |
| 2026-05-25 12:00 |
17:46:58.40 |
-31:24:31.5 |
HIP 87022 |
10.45 |
| 2026-05-26 00:00 |
17:46:48.07 |
-31:24:58.8 |
HIP 87022 |
9.96 |
| 2026-05-26 12:00 |
17:46:37.68 |
-31:25:25.8 |
HIP 87022 |
9.98 |
| 2026-05-27 00:00 |
17:46:27.24 |
-31:25:52.5 |
HIP 87022 |
10.51 |
| 2026-05-27 12:00 |
17:46:16.74 |
-31:26:19.0 |
HIP 87022 |
11.48 |
| 2026-05-28 00:00 |
17:46:06.20 |
-31:26:45.1 |
HIP 87022 |
12.80 |
| 2026-05-28 12:00 |
17:45:55.60 |
-31:27:11.0 |
HIP 87022 |
14.38 |
| 2026-05-29 00:00 |
17:45:44.95 |
-31:27:36.6 |
HIP 87022 |
16.14 |
| 2026-05-29 12:00 |
17:45:34.25 |
-31:28:02.0 |
HIP 87022 |
18.04 |
| 2026-05-30 00:00 |
17:45:23.51 |
-31:28:27.0 |
HIP 87022 |
20.04 |
| 2026-05-30 12:00 |
17:45:12.72 |
-31:28:51.7 |
HIP 87022 |
22.11 |
| 2026-05-31 00:00 |
17:45:01.88 |
-31:29:16.2 |
HIP 87022 |
24.24 |
| 2026-05-31 12:00 |
17:44:51.00 |
-31:29:40.4 |
HIP 87022 |
26.42 |
| 2026-06-01 00:00 |
17:44:40.08 |
-31:30:04.3 |
HIP 87022 |
28.63 |
| 2026-06-01 12:00 |
17:44:29.12 |
-31:30:27.8 |
HIP 87022 |
30.88 |
| 2026-06-02 00:00 |
17:44:18.12 |
-31:30:51.1 |
HIP 86617 |
31.57 |