メタデータ
| 項目 |
値 |
| Designation |
C/2019 Y1 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-03-15T13:31:42.720960Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:34:02Z |
| Obs used |
1010 |
| NEO |
- |
| M1 |
11.900 |
| K1 |
21.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-12-16T05:25:48.432000Z |
| Discovery magnitude (MPC) |
17.90 o |
| Discovery observatory (MPC) |
T05 · ATLAS-HKO, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2020-04-12.0000000 |
| e |
0.99650778 |
| q (au) |
0.837824 |
| a (au) |
239.911751 |
| i (deg) |
73.348136 |
| Ω (om, deg) |
31.366339 |
| ω (w, deg) |
57.498171 |
| M (ma, deg) |
0.007277 |
等級
散乱 + 全体線形
$$
M_a = (10.361 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.361 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2019-12-16 |
2020-01-18 |
+16.5581 |
-1.194 |
| 2020-01-18 |
2020-03-15 |
+7.5651 |
-0.659 |
| 2020-03-15 |
2020-07-12 |
+2.0051 |
-1.445 |
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 |
13:28:59.00 |
-43:53:46.3 |
HIP 65762 |
9.57 |
| 2026-07-29 12:00 |
13:29:00.78 |
-43:53:06.9 |
HIP 65762 |
8.94 |
| 2026-07-30 00:00 |
13:29:02.63 |
-43:52:27.8 |
HIP 65762 |
8.34 |
| 2026-07-30 12:00 |
13:29:04.54 |
-43:51:49.2 |
HIP 65762 |
7.77 |
| 2026-07-31 00:00 |
13:29:06.52 |
-43:51:10.9 |
HIP 65762 |
7.23 |
| 2026-07-31 12:00 |
13:29:08.56 |
-43:50:33.0 |
HIP 65762 |
6.75 |
| 2026-08-01 00:00 |
13:29:10.67 |
-43:49:55.4 |
HIP 65762 |
6.32 |
| 2026-08-01 12:00 |
13:29:12.84 |
-43:49:18.3 |
HIP 65762 |
5.96 |
| 2026-08-02 00:00 |
13:29:15.07 |
-43:48:41.5 |
HIP 65762 |
5.68 |
| 2026-08-02 12:00 |
13:29:17.37 |
-43:48:05.2 |
HIP 65762 |
5.51 |
| 2026-08-03 00:00 |
13:29:19.73 |
-43:47:29.2 |
HIP 65762 |
5.44 |
| 2026-08-03 12:00 |
13:29:22.15 |
-43:46:53.6 |
HIP 65762 |
5.48 |
| 2026-08-04 00:00 |
13:29:24.63 |
-43:46:18.5 |
HIP 65762 |
5.63 |
| 2026-08-04 12:00 |
13:29:27.18 |
-43:45:43.7 |
HIP 65762 |
5.89 |
| 2026-08-05 00:00 |
13:29:29.79 |
-43:45:09.3 |
HIP 65762 |
6.24 |
| 2026-08-05 12:00 |
13:29:32.46 |
-43:44:35.3 |
HIP 65762 |
6.66 |
| 2026-08-06 00:00 |
13:29:35.20 |
-43:44:01.7 |
HIP 65762 |
7.14 |
| 2026-08-06 12:00 |
13:29:37.99 |
-43:43:28.6 |
HIP 65762 |
7.68 |
| 2026-08-07 00:00 |
13:29:40.85 |
-43:42:55.8 |
HIP 65762 |
8.26 |
| 2026-08-07 12:00 |
13:29:43.77 |
-43:42:23.5 |
HIP 65762 |
8.88 |
| 2026-08-08 00:00 |
13:29:46.74 |
-43:41:51.6 |
HIP 65762 |
9.53 |
| 2026-08-08 12:00 |
13:29:49.78 |
-43:41:20.1 |
HIP 65762 |
10.20 |
| 2026-08-09 00:00 |
13:29:52.88 |
-43:40:49.0 |
HIP 65762 |
10.89 |
| 2026-08-09 12:00 |
13:29:56.04 |
-43:40:18.3 |
HIP 65762 |
11.59 |
| 2026-08-10 00:00 |
13:29:59.26 |
-43:39:48.1 |
HIP 65762 |
12.31 |
| 2026-08-10 12:00 |
13:30:02.53 |
-43:39:18.3 |
HIP 65762 |
13.05 |
| 2026-08-11 00:00 |
13:30:05.87 |
-43:38:48.9 |
HIP 65762 |
13.79 |
| 2026-08-11 12:00 |
13:30:09.27 |
-43:38:19.9 |
HIP 65762 |
14.55 |
| 2026-08-12 00:00 |
13:30:12.72 |
-43:37:51.4 |
HIP 65762 |
15.32 |
| 2026-08-12 12:00 |
13:30:16.23 |
-43:37:23.3 |
HIP 65762 |
16.09 |
| 2026-08-13 00:00 |
13:30:19.80 |
-43:36:55.6 |
HIP 65762 |
16.87 |
| 2026-08-13 12:00 |
13:30:23.43 |
-43:36:28.4 |
HIP 65762 |
17.66 |
| 2026-08-14 00:00 |
13:30:27.11 |
-43:36:01.6 |
HIP 65762 |
18.46 |
| 2026-08-14 12:00 |
13:30:30.86 |
-43:35:35.3 |
HIP 65762 |
19.26 |
| 2026-08-15 00:00 |
13:30:34.65 |
-43:35:09.4 |
HIP 65762 |
20.07 |
| 2026-08-15 12:00 |
13:30:38.51 |
-43:34:43.9 |
HIP 65762 |
20.88 |
| 2026-08-16 00:00 |
13:30:42.42 |
-43:34:18.9 |
HIP 65762 |
21.70 |
| 2026-08-16 12:00 |
13:30:46.38 |
-43:33:54.4 |
HIP 65762 |
22.53 |
| 2026-08-17 00:00 |
13:30:50.40 |
-43:33:30.3 |
HIP 65762 |
23.36 |
| 2026-08-17 12:00 |
13:30:54.47 |
-43:33:06.6 |
HIP 65762 |
24.20 |
| 2026-08-18 00:00 |
13:30:58.60 |
-43:32:43.4 |
HIP 65762 |
25.04 |
| 2026-08-18 12:00 |
13:31:02.78 |
-43:32:20.6 |
HIP 65762 |
25.89 |
| 2026-08-19 00:00 |
13:31:07.02 |
-43:31:58.3 |
HIP 66139 |
26.68 |