メタデータ
| 項目 |
値 |
| Designation |
C/2020 M3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-10-25T14:58:23.448000Z |
| Orbit solution date (soln_date, UTC) |
2022-04-23T03:12:26Z |
| Obs used |
2344 |
| NEO |
Yes |
| M1 |
14.600 |
| K1 |
6.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-06-27T13:57:10.627200Z |
| Discovery magnitude (MPC) |
18.89 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) |
2020-11-26.0000000 |
| e |
0.95270763 |
| q (au) |
1.268249 |
| a (au) |
26.817195 |
| i (deg) |
23.473528 |
| Ω (om, deg) |
71.250235 |
| ω (w, deg) |
328.446314 |
| M (ma, deg) |
0.222681 |
等級
散乱 + 全体線形
$$
M_a = (14.015 + 2.681\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.015 |
| n |
2.681 |
| gf |
0.993 |
| gb |
-1.000 |
| k |
0.999 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2012-01-10 |
2020-08-06 |
-14.0320 |
+4.994 |
| 2020-08-06 |
2020-10-25 |
+30.0861 |
-5.641 |
| 2020-10-25 |
2021-06-10 |
+4.2695 |
-2.068 |
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) |
| 2026-05-12 00:00 |
13:13:27.33 |
+15:15:29.2 |
HIP 64490 |
5.96 |
| 2026-05-12 12:00 |
13:13:21.45 |
+15:15:32.9 |
HIP 64490 |
4.86 |
| 2026-05-13 00:00 |
13:13:15.61 |
+15:15:36.0 |
HIP 64490 |
3.97 |
| 2026-05-13 12:00 |
13:13:09.81 |
+15:15:38.6 |
HIP 64490 |
3.45 |
| 2026-05-14 00:00 |
13:13:04.05 |
+15:15:40.6 |
HIP 64490 |
3.48 |
| 2026-05-14 12:00 |
13:12:58.33 |
+15:15:42.1 |
HIP 64490 |
4.01 |
| 2026-05-15 00:00 |
13:12:52.65 |
+15:15:43.1 |
HIP 64490 |
4.89 |
| 2026-05-15 12:00 |
13:12:47.02 |
+15:15:43.5 |
HIP 64490 |
5.96 |
| 2026-05-16 00:00 |
13:12:41.43 |
+15:15:43.3 |
HIP 64490 |
7.11 |
| 2026-05-16 12:00 |
13:12:35.89 |
+15:15:42.6 |
HIP 64490 |
8.32 |
| 2026-05-17 00:00 |
13:12:30.38 |
+15:15:41.4 |
HIP 64490 |
9.56 |
| 2026-05-17 12:00 |
13:12:24.93 |
+15:15:39.6 |
HIP 64490 |
10.81 |
| 2026-05-18 00:00 |
13:12:19.52 |
+15:15:37.3 |
HIP 64490 |
12.07 |
| 2026-05-18 12:00 |
13:12:14.15 |
+15:15:34.4 |
HIP 64490 |
13.33 |
| 2026-05-19 00:00 |
13:12:08.83 |
+15:15:31.0 |
HIP 64490 |
14.58 |
| 2026-05-19 12:00 |
13:12:03.56 |
+15:15:27.1 |
HIP 64490 |
15.83 |
| 2026-05-20 00:00 |
13:11:58.34 |
+15:15:22.6 |
HIP 64490 |
17.08 |
| 2026-05-20 12:00 |
13:11:53.16 |
+15:15:17.6 |
HIP 64490 |
18.32 |
| 2026-05-21 00:00 |
13:11:48.03 |
+15:15:12.1 |
HIP 64490 |
19.55 |
| 2026-05-21 12:00 |
13:11:42.95 |
+15:15:06.0 |
HIP 64490 |
20.77 |
| 2026-05-22 00:00 |
13:11:37.92 |
+15:14:59.4 |
HIP 64255 |
21.28 |
| 2026-05-22 12:00 |
13:11:32.93 |
+15:14:52.2 |
HIP 64255 |
20.09 |
| 2026-05-23 00:00 |
13:11:28.00 |
+15:14:44.6 |
HIP 64255 |
18.92 |
| 2026-05-23 12:00 |
13:11:23.12 |
+15:14:36.4 |
HIP 64255 |
17.75 |
| 2026-05-24 00:00 |
13:11:18.28 |
+15:14:27.6 |
HIP 64255 |
16.60 |
| 2026-05-24 12:00 |
13:11:13.50 |
+15:14:18.4 |
HIP 64255 |
15.45 |
| 2026-05-25 00:00 |
13:11:08.76 |
+15:14:08.6 |
HIP 64255 |
14.32 |
| 2026-05-25 12:00 |
13:11:04.08 |
+15:13:58.3 |
HIP 64255 |
13.21 |
| 2026-05-26 00:00 |
13:10:59.45 |
+15:13:47.5 |
HIP 64255 |
12.10 |
| 2026-05-26 12:00 |
13:10:54.87 |
+15:13:36.2 |
HIP 64255 |
11.01 |
| 2026-05-27 00:00 |
13:10:50.34 |
+15:13:24.4 |
HIP 64255 |
9.93 |
| 2026-05-27 12:00 |
13:10:45.87 |
+15:13:12.0 |
HIP 64255 |
8.87 |
| 2026-05-28 00:00 |
13:10:41.44 |
+15:12:59.2 |
HIP 64255 |
7.82 |
| 2026-05-28 12:00 |
13:10:37.07 |
+15:12:45.8 |
HIP 64255 |
6.80 |
| 2026-05-29 00:00 |
13:10:32.75 |
+15:12:31.9 |
HIP 64255 |
5.80 |
| 2026-05-29 12:00 |
13:10:28.49 |
+15:12:17.6 |
HIP 64255 |
4.83 |
| 2026-05-30 00:00 |
13:10:24.28 |
+15:12:02.7 |
HIP 64255 |
3.92 |
| 2026-05-30 12:00 |
13:10:20.12 |
+15:11:47.3 |
HIP 64255 |
3.08 |
| 2026-05-31 00:00 |
13:10:16.02 |
+15:11:31.4 |
HIP 64255 |
2.41 |
| 2026-05-31 12:00 |
13:10:11.97 |
+15:11:15.0 |
HIP 64255 |
2.04 |
| 2026-06-01 00:00 |
13:10:07.97 |
+15:10:58.1 |
HIP 64255 |
2.12 |
| 2026-06-01 12:00 |
13:10:04.03 |
+15:10:40.8 |
HIP 64255 |
2.60 |
| 2026-06-02 00:00 |
13:10:00.15 |
+15:10:22.9 |
HIP 64255 |
3.31 |