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 |
-0.500 |
| 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
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) |
| 2026-03-26 00:00 |
13:52:52.93 |
-46:43:52.6 |
HIP 67663 |
15.07 |
| 2026-03-26 12:00 |
13:52:44.25 |
-46:43:58.4 |
HIP 67663 |
13.93 |
| 2026-03-27 00:00 |
13:52:35.53 |
-46:44:03.6 |
HIP 67663 |
12.86 |
| 2026-03-27 12:00 |
13:52:26.78 |
-46:44:08.2 |
HIP 67663 |
11.89 |
| 2026-03-28 00:00 |
13:52:17.99 |
-46:44:12.2 |
HIP 67663 |
11.05 |
| 2026-03-28 12:00 |
13:52:09.17 |
-46:44:15.5 |
HIP 67663 |
10.36 |
| 2026-03-29 00:00 |
13:52:00.31 |
-46:44:18.3 |
HIP 67663 |
9.87 |
| 2026-03-29 12:00 |
13:51:51.43 |
-46:44:20.4 |
HIP 67663 |
9.60 |
| 2026-03-30 00:00 |
13:51:42.51 |
-46:44:21.9 |
HIP 67663 |
9.59 |
| 2026-03-30 12:00 |
13:51:33.56 |
-46:44:22.8 |
HIP 67663 |
9.82 |
| 2026-03-31 00:00 |
13:51:24.58 |
-46:44:23.0 |
HIP 67663 |
10.29 |
| 2026-03-31 12:00 |
13:51:15.57 |
-46:44:22.6 |
HIP 67663 |
10.97 |
| 2026-04-01 00:00 |
13:51:06.53 |
-46:44:21.7 |
HIP 67663 |
11.82 |
| 2026-04-01 12:00 |
13:50:57.46 |
-46:44:20.1 |
HIP 67663 |
12.82 |
| 2026-04-02 00:00 |
13:50:48.37 |
-46:44:17.9 |
HIP 67663 |
13.93 |
| 2026-04-02 12:00 |
13:50:39.25 |
-46:44:15.0 |
HIP 67663 |
15.12 |
| 2026-04-03 00:00 |
13:50:30.11 |
-46:44:11.6 |
HIP 67421 |
14.83 |
| 2026-04-03 12:00 |
13:50:20.94 |
-46:44:07.5 |
HIP 67421 |
13.27 |
| 2026-04-04 00:00 |
13:50:11.75 |
-46:44:02.8 |
HIP 67421 |
11.71 |
| 2026-04-04 12:00 |
13:50:02.54 |
-46:43:57.6 |
HIP 67421 |
10.15 |
| 2026-04-05 00:00 |
13:49:53.30 |
-46:43:51.6 |
HIP 67421 |
8.60 |
| 2026-04-05 12:00 |
13:49:44.05 |
-46:43:45.1 |
HIP 67421 |
7.07 |
| 2026-04-06 00:00 |
13:49:34.77 |
-46:43:38.0 |
HIP 67421 |
5.56 |
| 2026-04-06 12:00 |
13:49:25.47 |
-46:43:30.2 |
HIP 67421 |
4.12 |
| 2026-04-07 00:00 |
13:49:16.16 |
-46:43:21.9 |
HIP 67421 |
2.86 |
| 2026-04-07 12:00 |
13:49:06.82 |
-46:43:12.9 |
HIP 67421 |
2.14 |
| 2026-04-08 00:00 |
13:48:57.47 |
-46:43:03.3 |
HIP 67421 |
2.48 |
| 2026-04-08 12:00 |
13:48:48.11 |
-46:42:53.1 |
HIP 67421 |
3.61 |
| 2026-04-09 00:00 |
13:48:38.73 |
-46:42:42.3 |
HIP 67421 |
5.01 |
| 2026-04-09 12:00 |
13:48:29.33 |
-46:42:30.9 |
HIP 67421 |
6.52 |
| 2026-04-10 00:00 |
13:48:19.92 |
-46:42:18.9 |
HIP 67421 |
8.08 |
| 2026-04-10 12:00 |
13:48:10.50 |
-46:42:06.3 |
HIP 67421 |
9.67 |
| 2026-04-11 00:00 |
13:48:01.07 |
-46:41:53.1 |
HIP 67421 |
11.28 |
| 2026-04-11 12:00 |
13:47:51.62 |
-46:41:39.2 |
HIP 67421 |
12.89 |
| 2026-04-12 00:00 |
13:47:42.17 |
-46:41:24.8 |
HIP 67421 |
14.52 |
| 2026-04-12 12:00 |
13:47:32.70 |
-46:41:09.8 |
HIP 67421 |
16.15 |
| 2026-04-13 00:00 |
13:47:23.23 |
-46:40:54.2 |
HIP 67421 |
17.79 |
| 2026-04-13 12:00 |
13:47:13.75 |
-46:40:37.9 |
HIP 67421 |
19.43 |
| 2026-04-14 00:00 |
13:47:04.27 |
-46:40:21.1 |
HIP 67200 |
20.13 |
| 2026-04-14 12:00 |
13:46:54.78 |
-46:40:03.7 |
HIP 67200 |
19.25 |
| 2026-04-15 00:00 |
13:46:45.28 |
-46:39:45.7 |
HIP 67200 |
18.46 |
| 2026-04-15 12:00 |
13:46:35.78 |
-46:39:27.1 |
HIP 67200 |
17.78 |
| 2026-04-16 00:00 |
13:46:26.28 |
-46:39:07.9 |
HIP 67200 |
17.23 |