メタデータ
| 項目 |
値 |
| Designation |
C/2020 S2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-12-21T22:27:29.819520Z |
| Orbit solution date (soln_date, UTC) |
2022-09-27T15:42:34Z |
| Obs used |
96 |
| NEO |
- |
| M1 |
16.300 |
| K1 |
13.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2020-09-16T07:49:20.697600Z |
| Discovery magnitude (MPC) |
20.75 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) |
2020-10-15.0000000 |
| e |
0.82748820 |
| q (au) |
1.756056 |
| a (au) |
10.179340 |
| i (deg) |
22.397832 |
| Ω (om, deg) |
197.685362 |
| ω (w, deg) |
202.263038 |
| M (ma, deg) |
357.938311 |
等級
散乱 + 全体線形
$$
M_a = (15.508 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.508 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-1.000 |
| 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) |
| 2026-06-01 00:00 |
12:34:39.10 |
-05:24:12.4 |
HIP 61400 |
15.34 |
| 2026-06-01 12:00 |
12:34:36.23 |
-05:23:41.6 |
HIP 61322 |
15.00 |
| 2026-06-02 00:00 |
12:34:33.42 |
-05:23:11.2 |
HIP 61322 |
14.14 |
| 2026-06-02 12:00 |
12:34:30.68 |
-05:22:41.2 |
HIP 61322 |
13.29 |
| 2026-06-03 00:00 |
12:34:28.02 |
-05:22:11.7 |
HIP 61322 |
12.47 |
| 2026-06-03 12:00 |
12:34:25.42 |
-05:21:42.7 |
HIP 61322 |
11.66 |
| 2026-06-04 00:00 |
12:34:22.90 |
-05:21:14.1 |
HIP 61322 |
10.87 |
| 2026-06-04 12:00 |
12:34:20.45 |
-05:20:46.0 |
HIP 61322 |
10.10 |
| 2026-06-05 00:00 |
12:34:18.07 |
-05:20:18.4 |
HIP 61322 |
9.35 |
| 2026-06-05 12:00 |
12:34:15.76 |
-05:19:51.2 |
HIP 61322 |
8.62 |
| 2026-06-06 00:00 |
12:34:13.53 |
-05:19:24.5 |
HIP 61322 |
7.91 |
| 2026-06-06 12:00 |
12:34:11.37 |
-05:18:58.2 |
HIP 61322 |
7.22 |
| 2026-06-07 00:00 |
12:34:09.27 |
-05:18:32.4 |
HIP 61322 |
6.54 |
| 2026-06-07 12:00 |
12:34:07.26 |
-05:18:07.1 |
HIP 61322 |
5.88 |
| 2026-06-08 00:00 |
12:34:05.31 |
-05:17:42.2 |
HIP 61322 |
5.25 |
| 2026-06-08 12:00 |
12:34:03.43 |
-05:17:17.8 |
HIP 61322 |
4.63 |
| 2026-06-09 00:00 |
12:34:01.63 |
-05:16:53.9 |
HIP 61322 |
4.03 |
| 2026-06-09 12:00 |
12:33:59.90 |
-05:16:30.4 |
HIP 61322 |
3.46 |
| 2026-06-10 00:00 |
12:33:58.25 |
-05:16:07.4 |
HIP 61322 |
2.90 |
| 2026-06-10 12:00 |
12:33:56.67 |
-05:15:44.9 |
HIP 61322 |
2.37 |
| 2026-06-11 00:00 |
12:33:55.15 |
-05:15:22.9 |
HIP 61322 |
1.86 |
| 2026-06-11 12:00 |
12:33:53.72 |
-05:15:01.3 |
HIP 61322 |
1.39 |
| 2026-06-12 00:00 |
12:33:52.35 |
-05:14:40.2 |
HIP 61322 |
0.97 |
| 2026-06-12 12:00 |
12:33:51.06 |
-05:14:19.6 |
HIP 61322 |
0.67 |
| 2026-06-13 00:00 |
12:33:49.85 |
-05:13:59.5 |
HIP 61322 |
0.64 |
| 2026-06-13 12:00 |
12:33:48.70 |
-05:13:39.8 |
HIP 61322 |
0.87 |
| 2026-06-14 00:00 |
12:33:47.63 |
-05:13:20.6 |
HIP 61322 |
1.21 |
| 2026-06-14 12:00 |
12:33:46.63 |
-05:13:01.9 |
HIP 61322 |
1.57 |
| 2026-06-15 00:00 |
12:33:45.71 |
-05:12:43.7 |
HIP 61322 |
1.94 |
| 2026-06-15 12:00 |
12:33:44.86 |
-05:12:26.0 |
HIP 61322 |
2.29 |
| 2026-06-16 00:00 |
12:33:44.08 |
-05:12:08.7 |
HIP 61322 |
2.63 |
| 2026-06-16 12:00 |
12:33:43.38 |
-05:11:52.0 |
HIP 61322 |
2.96 |
| 2026-06-17 00:00 |
12:33:42.75 |
-05:11:35.7 |
HIP 61322 |
3.27 |
| 2026-06-17 12:00 |
12:33:42.19 |
-05:11:19.9 |
HIP 61322 |
3.57 |
| 2026-06-18 00:00 |
12:33:41.71 |
-05:11:04.5 |
HIP 61322 |
3.85 |
| 2026-06-18 12:00 |
12:33:41.30 |
-05:10:49.7 |
HIP 61322 |
4.12 |
| 2026-06-19 00:00 |
12:33:40.97 |
-05:10:35.3 |
HIP 61322 |
4.37 |
| 2026-06-19 12:00 |
12:33:40.70 |
-05:10:21.4 |
HIP 61322 |
4.61 |
| 2026-06-20 00:00 |
12:33:40.51 |
-05:10:08.0 |
HIP 61322 |
4.83 |
| 2026-06-20 12:00 |
12:33:40.40 |
-05:09:55.1 |
HIP 61322 |
5.04 |
| 2026-06-21 00:00 |
12:33:40.35 |
-05:09:42.7 |
HIP 61322 |
5.23 |
| 2026-06-21 12:00 |
12:33:40.38 |
-05:09:30.7 |
HIP 61322 |
5.42 |
| 2026-06-22 00:00 |
12:33:40.48 |
-05:09:19.2 |
HIP 61322 |
5.59 |