メタデータ
| 項目 |
値 |
| Designation |
C/2020 P3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-04-20T20:06:04.121280Z |
| Orbit solution date (soln_date, UTC) |
2024-04-29T13:12:18Z |
| Obs used |
698 |
| NEO |
- |
| M1 |
5.800 |
| K1 |
10.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2020-08-09T13:40:41.433600Z |
| Discovery magnitude (MPC) |
19.01 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-07-14.0000000 |
| e |
0.99914404 |
| q (au) |
6.812376 |
| a (au) |
7958.786111 |
| i (deg) |
61.884995 |
| Ω (om, deg) |
19.484342 |
| ω (w, deg) |
82.246067 |
| M (ma, deg) |
0.000117 |
等級
散乱 + 全体線形
$$
M_a = (7.781 + 5.487\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.781 |
| n |
5.487 |
| gf |
0.998 |
| gb |
-0.906 |
| k |
0.800 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2021-05-24 |
2024-04-12 |
+10.1458 |
-9.061 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
12:53:44.66 |
+01:53:15.2 |
HIP 62835 |
17.96 |
| 2026-07-29 12:00 |
12:53:47.89 |
+01:52:06.5 |
HIP 62835 |
18.99 |
| 2026-07-30 00:00 |
12:53:51.18 |
+01:50:57.6 |
HIP 62835 |
20.08 |
| 2026-07-30 12:00 |
12:53:54.52 |
+01:49:48.4 |
HIP 62835 |
21.23 |
| 2026-07-31 00:00 |
12:53:57.91 |
+01:48:39.1 |
HIP 62835 |
22.42 |
| 2026-07-31 12:00 |
12:54:01.37 |
+01:47:29.5 |
HIP 62835 |
23.65 |
| 2026-08-01 00:00 |
12:54:04.87 |
+01:46:19.7 |
HIP 63017 |
23.22 |
| 2026-08-01 12:00 |
12:54:08.43 |
+01:45:09.6 |
HIP 63017 |
21.77 |
| 2026-08-02 00:00 |
12:54:12.05 |
+01:43:59.4 |
HIP 63017 |
20.30 |
| 2026-08-02 12:00 |
12:54:15.71 |
+01:42:48.9 |
HIP 63017 |
18.83 |
| 2026-08-03 00:00 |
12:54:19.44 |
+01:41:38.3 |
HIP 63017 |
17.36 |
| 2026-08-03 12:00 |
12:54:23.21 |
+01:40:27.4 |
HIP 63017 |
15.87 |
| 2026-08-04 00:00 |
12:54:27.04 |
+01:39:16.3 |
HIP 63017 |
14.39 |
| 2026-08-04 12:00 |
12:54:30.92 |
+01:38:05.0 |
HIP 63017 |
12.91 |
| 2026-08-05 00:00 |
12:54:34.85 |
+01:36:53.5 |
HIP 63017 |
11.43 |
| 2026-08-05 12:00 |
12:54:38.84 |
+01:35:41.8 |
HIP 63017 |
9.96 |
| 2026-08-06 00:00 |
12:54:42.88 |
+01:34:29.9 |
HIP 63052 |
8.50 |
| 2026-08-06 12:00 |
12:54:46.97 |
+01:33:17.8 |
HIP 63052 |
6.96 |
| 2026-08-07 00:00 |
12:54:51.11 |
+01:32:05.5 |
HIP 63052 |
5.42 |
| 2026-08-07 12:00 |
12:54:55.30 |
+01:30:53.1 |
HIP 63052 |
3.90 |
| 2026-08-08 00:00 |
12:54:59.55 |
+01:29:40.4 |
HIP 63052 |
2.48 |
| 2026-08-08 12:00 |
12:55:03.84 |
+01:28:27.5 |
HIP 63052 |
1.49 |
| 2026-08-09 00:00 |
12:55:08.18 |
+01:27:14.5 |
HIP 63052 |
1.89 |
| 2026-08-09 12:00 |
12:55:12.58 |
+01:26:01.3 |
HIP 63052 |
3.21 |
| 2026-08-10 00:00 |
12:55:17.02 |
+01:24:47.9 |
HIP 63052 |
4.74 |
| 2026-08-10 12:00 |
12:55:21.51 |
+01:23:34.3 |
HIP 63052 |
6.34 |
| 2026-08-11 00:00 |
12:55:26.06 |
+01:22:20.5 |
HIP 63052 |
7.97 |
| 2026-08-11 12:00 |
12:55:30.65 |
+01:21:06.6 |
HIP 63052 |
9.63 |
| 2026-08-12 00:00 |
12:55:35.29 |
+01:19:52.5 |
HIP 63052 |
11.31 |
| 2026-08-12 12:00 |
12:55:39.97 |
+01:18:38.2 |
HIP 63052 |
13.00 |
| 2026-08-13 00:00 |
12:55:44.71 |
+01:17:23.7 |
HIP 63052 |
14.70 |
| 2026-08-13 12:00 |
12:55:49.49 |
+01:16:09.1 |
HIP 63052 |
16.41 |
| 2026-08-14 00:00 |
12:55:54.32 |
+01:14:54.4 |
HIP 63052 |
18.14 |
| 2026-08-14 12:00 |
12:55:59.19 |
+01:13:39.4 |
HIP 63052 |
19.87 |
| 2026-08-15 00:00 |
12:56:04.11 |
+01:12:24.4 |
HIP 63052 |
21.62 |
| 2026-08-15 12:00 |
12:56:09.08 |
+01:11:09.1 |
HIP 63052 |
23.38 |
| 2026-08-16 00:00 |
12:56:14.09 |
+01:09:53.8 |
HIP 63235 |
23.98 |
| 2026-08-16 12:00 |
12:56:19.15 |
+01:08:38.2 |
HIP 63235 |
23.92 |
| 2026-08-17 00:00 |
12:56:24.25 |
+01:07:22.6 |
HIP 63235 |
23.99 |
| 2026-08-17 12:00 |
12:56:29.40 |
+01:06:06.8 |
HIP 63235 |
24.19 |
| 2026-08-18 00:00 |
12:56:34.58 |
+01:04:50.8 |
HIP 63235 |
24.52 |
| 2026-08-18 12:00 |
12:56:39.82 |
+01:03:34.8 |
HIP 63235 |
24.97 |
| 2026-08-19 00:00 |
12:56:45.09 |
+01:02:18.5 |
HIP 63235 |
25.54 |