メタデータ
| 項目 |
値 |
| Designation |
C/2021 R2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-12-25T00:02:41.040960Z |
| Orbit solution date (soln_date, UTC) |
2022-12-08T23:43:01Z |
| Obs used |
126 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
10.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-09-05T08:07:54.134400Z |
| Discovery magnitude (MPC) |
20.48 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-11-08.0000000 |
| e |
0.99748693 |
| q (au) |
7.311968 |
| a (au) |
2909.581318 |
| i (deg) |
134.470894 |
| Ω (om, deg) |
16.283615 |
| ω (w, deg) |
32.298315 |
| M (ma, deg) |
359.999705 |
等級
散乱 + 全体線形
$$
M_a = (2.347 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
2.347 |
| 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 |
16:52:14.24 |
+17:53:28.6 |
HIP 82568 |
12.08 |
| 2026-09-20 12:00 |
16:52:13.88 |
+17:51:47.0 |
HIP 82568 |
13.59 |
| 2026-09-21 00:00 |
16:52:13.60 |
+17:50:05.6 |
HIP 82568 |
15.13 |
| 2026-09-21 12:00 |
16:52:13.40 |
+17:48:24.4 |
HIP 82568 |
16.68 |
| 2026-09-22 00:00 |
16:52:13.28 |
+17:46:43.4 |
HIP 82568 |
18.25 |
| 2026-09-22 12:00 |
16:52:13.23 |
+17:45:02.7 |
HIP 82568 |
19.83 |
| 2026-09-23 00:00 |
16:52:13.27 |
+17:43:22.2 |
HIP 82568 |
21.41 |
| 2026-09-23 12:00 |
16:52:13.38 |
+17:41:41.9 |
HIP 82568 |
23.00 |
| 2026-09-24 00:00 |
16:52:13.58 |
+17:40:01.9 |
HIP 82568 |
24.59 |
| 2026-09-24 12:00 |
16:52:13.84 |
+17:38:22.1 |
HIP 82568 |
26.18 |
| 2026-09-25 00:00 |
16:52:14.19 |
+17:36:42.5 |
HIP 82568 |
27.77 |
| 2026-09-25 12:00 |
16:52:14.61 |
+17:35:03.2 |
HIP 82568 |
29.36 |
| 2026-09-26 00:00 |
16:52:15.11 |
+17:33:24.2 |
HIP 82568 |
30.95 |
| 2026-09-26 12:00 |
16:52:15.69 |
+17:31:45.4 |
HIP 82568 |
32.54 |
| 2026-09-27 00:00 |
16:52:16.34 |
+17:30:07.0 |
HIP 82568 |
34.13 |
| 2026-09-27 12:00 |
16:52:17.07 |
+17:28:28.7 |
HIP 82568 |
35.71 |
| 2026-09-28 00:00 |
16:52:17.87 |
+17:26:50.8 |
HIP 82568 |
37.30 |
| 2026-09-28 12:00 |
16:52:18.74 |
+17:25:13.1 |
HIP 82568 |
38.88 |
| 2026-09-29 00:00 |
16:52:19.69 |
+17:23:35.8 |
HIP 82568 |
40.46 |
| 2026-09-29 12:00 |
16:52:20.72 |
+17:21:58.7 |
HIP 82568 |
42.04 |
| 2026-09-30 00:00 |
16:52:21.81 |
+17:20:21.9 |
HIP 82710 |
41.79 |
| 2026-09-30 12:00 |
16:52:22.98 |
+17:18:45.4 |
HIP 82710 |
40.45 |
| 2026-10-01 00:00 |
16:52:24.23 |
+17:17:09.2 |
HIP 82710 |
39.12 |
| 2026-10-01 12:00 |
16:52:25.54 |
+17:15:33.4 |
HIP 82710 |
37.81 |
| 2026-10-02 00:00 |
16:52:26.93 |
+17:13:57.8 |
HIP 82710 |
36.51 |
| 2026-10-02 12:00 |
16:52:28.39 |
+17:12:22.6 |
HIP 82710 |
35.23 |
| 2026-10-03 00:00 |
16:52:29.92 |
+17:10:47.7 |
HIP 82710 |
33.96 |
| 2026-10-03 12:00 |
16:52:31.52 |
+17:09:13.2 |
HIP 82710 |
32.72 |
| 2026-10-04 00:00 |
16:52:33.19 |
+17:07:39.0 |
HIP 82710 |
31.50 |
| 2026-10-04 12:00 |
16:52:34.93 |
+17:06:05.1 |
HIP 82710 |
30.31 |
| 2026-10-05 00:00 |
16:52:36.75 |
+17:04:31.5 |
HIP 82710 |
29.15 |
| 2026-10-05 12:00 |
16:52:38.63 |
+17:02:58.4 |
HIP 82710 |
28.02 |
| 2026-10-06 00:00 |
16:52:40.58 |
+17:01:25.5 |
HIP 82710 |
26.93 |
| 2026-10-06 12:00 |
16:52:42.60 |
+16:59:53.1 |
HIP 82710 |
25.88 |
| 2026-10-07 00:00 |
16:52:44.69 |
+16:58:21.0 |
HIP 82710 |
24.87 |
| 2026-10-07 12:00 |
16:52:46.84 |
+16:56:49.3 |
HIP 82710 |
23.92 |
| 2026-10-08 00:00 |
16:52:49.07 |
+16:55:17.9 |
HIP 82710 |
23.03 |
| 2026-10-08 12:00 |
16:52:51.36 |
+16:53:47.0 |
HIP 82710 |
22.20 |
| 2026-10-09 00:00 |
16:52:53.71 |
+16:52:16.4 |
HIP 82710 |
21.45 |
| 2026-10-09 12:00 |
16:52:56.13 |
+16:50:46.3 |
HIP 82710 |
20.78 |
| 2026-10-10 00:00 |
16:52:58.62 |
+16:49:16.5 |
HIP 82710 |
20.21 |
| 2026-10-10 12:00 |
16:53:01.18 |
+16:47:47.1 |
HIP 82710 |
19.72 |
| 2026-10-11 00:00 |
16:53:03.79 |
+16:46:18.1 |
HIP 82710 |
19.35 |