メタデータ
| 項目 |
値 |
| Designation |
C/2020 R2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-02-24T07:21:20.217600Z |
| Orbit solution date (soln_date, UTC) |
2024-03-19T12:12:36Z |
| Obs used |
386 |
| NEO |
- |
| M1 |
7.900 |
| K1 |
11.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-09-12T07:30:45.878400Z |
| Discovery magnitude (MPC) |
20.51 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) |
2021-07-17.0000000 |
| e |
0.98865011 |
| q (au) |
4.692155 |
| a (au) |
413.409849 |
| i (deg) |
53.224771 |
| Ω (om, deg) |
195.092039 |
| ω (w, deg) |
211.709686 |
| M (ma, deg) |
359.973933 |
等級
散乱 + 全体線形
$$
M_a = (7.419 + 4.508\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.419 |
| n |
4.508 |
| gf |
0.935 |
| gb |
-0.960 |
| k |
1.000 |
| δ90 |
1.000 |
| 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) |
| 2026-07-29 00:00 |
09:59:11.12 |
-22:23:56.8 |
HIP 48912 |
8.52 |
| 2026-07-29 12:00 |
09:59:22.24 |
-22:23:56.0 |
HIP 48912 |
10.76 |
| 2026-07-30 00:00 |
09:59:33.37 |
-22:23:55.9 |
HIP 48912 |
13.13 |
| 2026-07-30 12:00 |
09:59:44.52 |
-22:23:56.4 |
HIP 48912 |
15.57 |
| 2026-07-31 00:00 |
09:59:55.68 |
-22:23:57.7 |
HIP 48937 |
17.43 |
| 2026-07-31 12:00 |
10:00:06.86 |
-22:23:59.6 |
HIP 48937 |
19.31 |
| 2026-08-01 00:00 |
10:00:18.06 |
-22:24:02.1 |
HIP 48937 |
21.35 |
| 2026-08-01 12:00 |
10:00:29.27 |
-22:24:05.4 |
HIP 48937 |
23.50 |
| 2026-08-02 00:00 |
10:00:40.49 |
-22:24:09.3 |
HIP 49099 |
23.22 |
| 2026-08-02 12:00 |
10:00:51.73 |
-22:24:13.9 |
HIP 49099 |
22.37 |
| 2026-08-03 00:00 |
10:01:02.98 |
-22:24:19.1 |
HIP 49099 |
21.78 |
| 2026-08-03 12:00 |
10:01:14.25 |
-22:24:25.1 |
HIP 49099 |
21.49 |
| 2026-08-04 00:00 |
10:01:25.52 |
-22:24:31.7 |
HIP 49099 |
21.49 |
| 2026-08-04 12:00 |
10:01:36.81 |
-22:24:38.9 |
HIP 49099 |
21.80 |
| 2026-08-05 00:00 |
10:01:48.12 |
-22:24:46.8 |
HIP 49099 |
22.40 |
| 2026-08-05 12:00 |
10:01:59.43 |
-22:24:55.4 |
HIP 49216 |
21.95 |
| 2026-08-06 00:00 |
10:02:10.75 |
-22:25:04.6 |
HIP 49216 |
20.89 |
| 2026-08-06 12:00 |
10:02:22.09 |
-22:25:14.5 |
HIP 49216 |
20.11 |
| 2026-08-07 00:00 |
10:02:33.43 |
-22:25:25.1 |
HIP 49216 |
19.68 |
| 2026-08-07 12:00 |
10:02:44.79 |
-22:25:36.3 |
HIP 49216 |
19.60 |
| 2026-08-08 00:00 |
10:02:56.15 |
-22:25:48.1 |
HIP 49216 |
19.88 |
| 2026-08-08 12:00 |
10:03:07.53 |
-22:26:00.6 |
HIP 49337 |
18.14 |
| 2026-08-09 00:00 |
10:03:18.91 |
-22:26:13.8 |
HIP 49337 |
15.68 |
| 2026-08-09 12:00 |
10:03:30.30 |
-22:26:27.6 |
HIP 49337 |
13.28 |
| 2026-08-10 00:00 |
10:03:41.69 |
-22:26:42.0 |
HIP 49337 |
10.99 |
| 2026-08-10 12:00 |
10:03:53.10 |
-22:26:57.1 |
HIP 49337 |
8.90 |
| 2026-08-11 00:00 |
10:04:04.50 |
-22:27:12.9 |
HIP 49337 |
7.16 |
| 2026-08-11 12:00 |
10:04:15.92 |
-22:27:29.2 |
HIP 49337 |
6.10 |
| 2026-08-12 00:00 |
10:04:27.34 |
-22:27:46.2 |
HIP 49337 |
6.09 |
| 2026-08-12 12:00 |
10:04:38.76 |
-22:28:03.9 |
HIP 49337 |
7.14 |
| 2026-08-13 00:00 |
10:04:50.19 |
-22:28:22.1 |
HIP 49337 |
8.88 |
| 2026-08-13 12:00 |
10:05:01.63 |
-22:28:41.0 |
HIP 49337 |
10.99 |
| 2026-08-14 00:00 |
10:05:13.06 |
-22:29:00.5 |
HIP 49337 |
13.30 |
| 2026-08-14 12:00 |
10:05:24.50 |
-22:29:20.7 |
HIP 49337 |
15.71 |
| 2026-08-15 00:00 |
10:05:35.94 |
-22:29:41.4 |
HIP 49337 |
18.19 |
| 2026-08-15 12:00 |
10:05:47.39 |
-22:30:02.8 |
HIP 49337 |
20.72 |
| 2026-08-16 00:00 |
10:05:58.83 |
-22:30:24.8 |
HIP 49610 |
21.58 |
| 2026-08-16 12:00 |
10:06:10.27 |
-22:30:47.4 |
HIP 49610 |
18.97 |
| 2026-08-17 00:00 |
10:06:21.72 |
-22:31:10.6 |
HIP 49610 |
16.37 |
| 2026-08-17 12:00 |
10:06:33.16 |
-22:31:34.4 |
HIP 49610 |
13.80 |
| 2026-08-18 00:00 |
10:06:44.61 |
-22:31:58.9 |
HIP 49610 |
11.29 |
| 2026-08-18 12:00 |
10:06:56.05 |
-22:32:23.9 |
HIP 49610 |
8.87 |
| 2026-08-19 00:00 |
10:07:07.49 |
-22:32:49.5 |
HIP 49610 |
6.66 |