メタデータ
| 項目 |
値 |
| Designation |
C/2020 F2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-07-15T21:34:18.912000Z |
| Orbit solution date (soln_date, UTC) |
2026-03-07T14:42:52Z |
| Obs used |
1649 |
| NEO |
- |
| M1 |
6.300 |
| K1 |
7.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2022-04-08.0000000 |
| e |
1.00484187 |
| q (au) |
8.817057 |
| a (au) |
-1821.002957 |
| i (deg) |
163.583705 |
| Ω (om, deg) |
250.268049 |
| ω (w, deg) |
48.361233 |
| M (ma, deg) |
-0.001254 |
等級
散乱 + 全体線形
$$
M_a = (-1.509 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
-1.509 |
| n |
6.000 |
| gf |
0.831 |
| gb |
-0.928 |
| k |
1.000 |
| δ90 |
1.136 |
| 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 |
| 2019-05-27 |
2022-07-14 |
+9.9375 |
-9.585 |
| 2022-07-16 |
2026-02-20 |
+11.9466 |
-11.468 |
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) |
| 2026-06-01 00:00 |
09:32:13.30 |
+30:25:05.7 |
HIP 46868 |
13.85 |
| 2026-06-01 12:00 |
09:32:13.08 |
+30:24:25.2 |
HIP 46868 |
14.33 |
| 2026-06-02 00:00 |
09:32:12.94 |
+30:23:44.4 |
HIP 46868 |
14.82 |
| 2026-06-02 12:00 |
09:32:12.88 |
+30:23:03.5 |
HIP 46868 |
15.32 |
| 2026-06-03 00:00 |
09:32:12.91 |
+30:22:22.5 |
HIP 46868 |
15.82 |
| 2026-06-03 12:00 |
09:32:13.02 |
+30:21:41.2 |
HIP 46868 |
16.32 |
| 2026-06-04 00:00 |
09:32:13.21 |
+30:20:59.8 |
HIP 46868 |
16.83 |
| 2026-06-04 12:00 |
09:32:13.48 |
+30:20:18.3 |
HIP 46868 |
17.35 |
| 2026-06-05 00:00 |
09:32:13.82 |
+30:19:36.6 |
HIP 46868 |
17.86 |
| 2026-06-05 12:00 |
09:32:14.25 |
+30:18:54.8 |
HIP 46868 |
18.38 |
| 2026-06-06 00:00 |
09:32:14.76 |
+30:18:12.8 |
HIP 46868 |
18.91 |
| 2026-06-06 12:00 |
09:32:15.35 |
+30:17:30.7 |
HIP 46868 |
19.44 |
| 2026-06-07 00:00 |
09:32:16.02 |
+30:16:48.4 |
HIP 46868 |
19.97 |
| 2026-06-07 12:00 |
09:32:16.76 |
+30:16:06.1 |
HIP 46868 |
20.51 |
| 2026-06-08 00:00 |
09:32:17.58 |
+30:15:23.5 |
HIP 46868 |
21.06 |
| 2026-06-08 12:00 |
09:32:18.48 |
+30:14:40.9 |
HIP 46868 |
21.61 |
| 2026-06-09 00:00 |
09:32:19.46 |
+30:13:58.1 |
HIP 46868 |
22.17 |
| 2026-06-09 12:00 |
09:32:20.51 |
+30:13:15.2 |
HIP 46868 |
22.73 |
| 2026-06-10 00:00 |
09:32:21.64 |
+30:12:32.2 |
HIP 46868 |
23.30 |
| 2026-06-10 12:00 |
09:32:22.84 |
+30:11:49.1 |
HIP 46868 |
23.88 |
| 2026-06-11 00:00 |
09:32:24.12 |
+30:11:05.9 |
HIP 46868 |
24.46 |
| 2026-06-11 12:00 |
09:32:25.47 |
+30:10:22.6 |
HIP 46868 |
25.05 |
| 2026-06-12 00:00 |
09:32:26.90 |
+30:09:39.1 |
HIP 46868 |
25.65 |
| 2026-06-12 12:00 |
09:32:28.39 |
+30:08:55.6 |
HIP 46868 |
26.25 |
| 2026-06-13 00:00 |
09:32:29.97 |
+30:08:12.0 |
HIP 46868 |
26.86 |
| 2026-06-13 12:00 |
09:32:31.61 |
+30:07:28.3 |
HIP 46868 |
27.48 |
| 2026-06-14 00:00 |
09:32:33.32 |
+30:06:44.4 |
HIP 46868 |
28.11 |
| 2026-06-14 12:00 |
09:32:35.11 |
+30:06:00.6 |
HIP 46868 |
28.74 |
| 2026-06-15 00:00 |
09:32:36.97 |
+30:05:16.6 |
HIP 46868 |
29.38 |
| 2026-06-15 12:00 |
09:32:38.89 |
+30:04:32.5 |
HIP 46868 |
30.03 |
| 2026-06-16 00:00 |
09:32:40.89 |
+30:03:48.4 |
HIP 46868 |
30.69 |
| 2026-06-16 12:00 |
09:32:42.95 |
+30:03:04.2 |
HIP 46868 |
31.36 |
| 2026-06-17 00:00 |
09:32:45.09 |
+30:02:20.0 |
HIP 46868 |
32.04 |
| 2026-06-17 12:00 |
09:32:47.29 |
+30:01:35.6 |
HIP 46868 |
32.72 |
| 2026-06-18 00:00 |
09:32:49.55 |
+30:00:51.3 |
HIP 46868 |
33.42 |
| 2026-06-18 12:00 |
09:32:51.89 |
+30:00:06.8 |
HIP 46868 |
34.12 |
| 2026-06-19 00:00 |
09:32:54.29 |
+29:59:22.4 |
HIP 46868 |
34.83 |
| 2026-06-19 12:00 |
09:32:56.75 |
+29:58:37.8 |
HIP 46868 |
35.55 |
| 2026-06-20 00:00 |
09:32:59.28 |
+29:57:53.3 |
HIP 46868 |
36.28 |
| 2026-06-20 12:00 |
09:33:01.87 |
+29:57:08.7 |
HIP 46868 |
37.02 |
| 2026-06-21 00:00 |
09:33:04.52 |
+29:56:24.0 |
HIP 46868 |
37.77 |
| 2026-06-21 12:00 |
09:33:07.24 |
+29:55:39.3 |
HIP 46868 |
38.53 |
| 2026-06-22 00:00 |
09:33:10.02 |
+29:54:54.6 |
HIP 46868 |
39.29 |