メタデータ
| 項目 |
値 |
| Designation |
C/2020 A3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-06-28T20:34:35.627520Z |
| Orbit solution date (soln_date, UTC) |
2023-01-14T00:12:32Z |
| Obs used |
94 |
| NEO |
- |
| M1 |
6.800 |
| K1 |
11.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-01-07T14:18:44.640000Z |
| Discovery magnitude (MPC) |
18.92 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) |
2019-10-25.0000000 |
| e |
0.99890265 |
| q (au) |
5.766807 |
| a (au) |
5255.225488 |
| i (deg) |
146.700275 |
| Ω (om, deg) |
120.792469 |
| ω (w, deg) |
268.410013 |
| M (ma, deg) |
0.000306 |
等級
散乱 + 全体線形
$$
M_a = (2.943 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
2.943 |
| 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) |
| 2026-05-12 00:00 |
07:07:43.98 |
+30:54:49.1 |
HIP 34456 |
34.80 |
| 2026-05-12 12:00 |
07:07:47.33 |
+30:54:43.4 |
HIP 34456 |
34.68 |
| 2026-05-13 00:00 |
07:07:50.73 |
+30:54:37.7 |
HIP 34456 |
34.57 |
| 2026-05-13 12:00 |
07:07:54.19 |
+30:54:32.0 |
HIP 34456 |
34.48 |
| 2026-05-14 00:00 |
07:07:57.69 |
+30:54:26.2 |
HIP 34456 |
34.40 |
| 2026-05-14 12:00 |
07:08:01.25 |
+30:54:20.5 |
HIP 34456 |
34.33 |
| 2026-05-15 00:00 |
07:08:04.86 |
+30:54:14.8 |
HIP 34521 |
34.07 |
| 2026-05-15 12:00 |
07:08:08.51 |
+30:54:09.0 |
HIP 34521 |
33.67 |
| 2026-05-16 00:00 |
07:08:12.22 |
+30:54:03.3 |
HIP 34521 |
33.27 |
| 2026-05-16 12:00 |
07:08:15.97 |
+30:53:57.6 |
HIP 34521 |
32.89 |
| 2026-05-17 00:00 |
07:08:19.77 |
+30:53:51.8 |
HIP 34521 |
32.51 |
| 2026-05-17 12:00 |
07:08:23.62 |
+30:53:46.1 |
HIP 34521 |
32.16 |
| 2026-05-18 00:00 |
07:08:27.51 |
+30:53:40.4 |
HIP 34521 |
31.81 |
| 2026-05-18 12:00 |
07:08:31.46 |
+30:53:34.7 |
HIP 34521 |
31.49 |
| 2026-05-19 00:00 |
07:08:35.45 |
+30:53:29.0 |
HIP 34521 |
31.18 |
| 2026-05-19 12:00 |
07:08:39.48 |
+30:53:23.2 |
HIP 34521 |
30.88 |
| 2026-05-20 00:00 |
07:08:43.56 |
+30:53:17.6 |
HIP 34521 |
30.61 |
| 2026-05-20 12:00 |
07:08:47.69 |
+30:53:11.9 |
HIP 34521 |
30.37 |
| 2026-05-21 00:00 |
07:08:51.85 |
+30:53:06.2 |
HIP 34521 |
30.14 |
| 2026-05-21 12:00 |
07:08:56.07 |
+30:53:00.5 |
HIP 34521 |
29.94 |
| 2026-05-22 00:00 |
07:09:00.32 |
+30:52:54.9 |
HIP 34521 |
29.77 |
| 2026-05-22 12:00 |
07:09:04.62 |
+30:52:49.3 |
HIP 34521 |
29.62 |
| 2026-05-23 00:00 |
07:09:08.97 |
+30:52:43.6 |
HIP 34521 |
29.50 |
| 2026-05-23 12:00 |
07:09:13.35 |
+30:52:38.0 |
HIP 34521 |
29.41 |
| 2026-05-24 00:00 |
07:09:17.78 |
+30:52:32.5 |
HIP 34521 |
29.35 |
| 2026-05-24 12:00 |
07:09:22.24 |
+30:52:26.9 |
HIP 34521 |
29.33 |
| 2026-05-25 00:00 |
07:09:26.75 |
+30:52:21.3 |
HIP 34521 |
29.34 |
| 2026-05-25 12:00 |
07:09:31.30 |
+30:52:15.8 |
HIP 34521 |
29.38 |
| 2026-05-26 00:00 |
07:09:35.89 |
+30:52:10.3 |
HIP 34521 |
29.46 |
| 2026-05-26 12:00 |
07:09:40.51 |
+30:52:04.8 |
HIP 34521 |
29.57 |
| 2026-05-27 00:00 |
07:09:45.18 |
+30:51:59.4 |
HIP 34521 |
29.72 |
| 2026-05-27 12:00 |
07:09:49.88 |
+30:51:53.9 |
HIP 34521 |
29.90 |
| 2026-05-28 00:00 |
07:09:54.62 |
+30:51:48.5 |
HIP 34521 |
30.12 |
| 2026-05-28 12:00 |
07:09:59.40 |
+30:51:43.2 |
HIP 34733 |
30.28 |
| 2026-05-29 00:00 |
07:10:04.22 |
+30:51:37.8 |
HIP 34733 |
29.56 |
| 2026-05-29 12:00 |
07:10:09.07 |
+30:51:32.5 |
HIP 34733 |
28.86 |
| 2026-05-30 00:00 |
07:10:13.96 |
+30:51:27.2 |
HIP 34733 |
28.17 |
| 2026-05-30 12:00 |
07:10:18.89 |
+30:51:21.9 |
HIP 34733 |
27.51 |
| 2026-05-31 00:00 |
07:10:23.85 |
+30:51:16.7 |
HIP 34733 |
26.86 |
| 2026-05-31 12:00 |
07:10:28.85 |
+30:51:11.5 |
HIP 34733 |
26.24 |
| 2026-06-01 00:00 |
07:10:33.88 |
+30:51:06.3 |
HIP 34733 |
25.65 |
| 2026-06-01 12:00 |
07:10:38.94 |
+30:51:01.2 |
HIP 34733 |
25.09 |
| 2026-06-02 00:00 |
07:10:44.04 |
+30:50:56.0 |
HIP 34733 |
24.56 |