メタデータ
| 項目 |
値 |
| Designation |
P/2019 A2 (ATLAS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-11-21T10:46:12.993600Z |
| Orbit solution date (soln_date, UTC) |
2021-08-06T00:42:48Z |
| Obs used |
284 |
| NEO |
- |
| M1 |
11.700 |
| K1 |
8.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2019-01-04T11:38:04.992000Z |
| Discovery magnitude (MPC) |
18.70 c |
| 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) |
2019-02-09.0000000 |
| e |
0.38199370 |
| q (au) |
3.542902 |
| a (au) |
5.732793 |
| i (deg) |
14.855261 |
| Ω (om, deg) |
139.462645 |
| ω (w, deg) |
324.226252 |
| M (ma, deg) |
5.712176 |
等級
散乱 + 全体線形
$$
M_a = (10.766 + 3.368\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.766 |
| n |
3.368 |
| gf |
0.800 |
| gb |
-0.581 |
| k |
1.000 |
| δ90 |
4.812 |
| 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) |
| 2026-09-20 00:00 |
19:22:52.39 |
-15:50:50.3 |
HIP 95323 |
10.95 |
| 2026-09-20 12:00 |
19:22:51.03 |
-15:51:32.8 |
HIP 95323 |
11.43 |
| 2026-09-21 00:00 |
19:22:49.80 |
-15:52:15.0 |
HIP 95323 |
11.90 |
| 2026-09-21 12:00 |
19:22:48.71 |
-15:52:57.0 |
HIP 95323 |
12.37 |
| 2026-09-22 00:00 |
19:22:47.75 |
-15:53:38.7 |
HIP 95323 |
12.84 |
| 2026-09-22 12:00 |
19:22:46.92 |
-15:54:20.1 |
HIP 95323 |
13.30 |
| 2026-09-23 00:00 |
19:22:46.22 |
-15:55:01.2 |
HIP 95323 |
13.75 |
| 2026-09-23 12:00 |
19:22:45.66 |
-15:55:42.1 |
HIP 95323 |
14.19 |
| 2026-09-24 00:00 |
19:22:45.24 |
-15:56:22.6 |
HIP 95323 |
14.62 |
| 2026-09-24 12:00 |
19:22:44.95 |
-15:57:02.9 |
HIP 95176 |
14.74 |
| 2026-09-25 00:00 |
19:22:44.79 |
-15:57:42.9 |
HIP 95176 |
14.71 |
| 2026-09-25 12:00 |
19:22:44.76 |
-15:58:22.6 |
HIP 95176 |
14.73 |
| 2026-09-26 00:00 |
19:22:44.87 |
-15:59:02.1 |
HIP 95176 |
14.82 |
| 2026-09-26 12:00 |
19:22:45.11 |
-15:59:41.2 |
HIP 95176 |
14.97 |
| 2026-09-27 00:00 |
19:22:45.48 |
-16:00:20.0 |
HIP 95176 |
15.17 |
| 2026-09-27 12:00 |
19:22:45.99 |
-16:00:58.6 |
HIP 95176 |
15.43 |
| 2026-09-28 00:00 |
19:22:46.63 |
-16:01:36.8 |
HIP 95176 |
15.74 |
| 2026-09-28 12:00 |
19:22:47.40 |
-16:02:14.8 |
HIP 95176 |
16.11 |
| 2026-09-29 00:00 |
19:22:48.31 |
-16:02:52.5 |
HIP 95176 |
16.51 |
| 2026-09-29 12:00 |
19:22:49.35 |
-16:03:29.8 |
HIP 95176 |
16.97 |
| 2026-09-30 00:00 |
19:22:50.52 |
-16:04:06.9 |
HIP 95176 |
17.46 |
| 2026-09-30 12:00 |
19:22:51.82 |
-16:04:43.6 |
HIP 95176 |
17.99 |
| 2026-10-01 00:00 |
19:22:53.26 |
-16:05:20.1 |
HIP 95176 |
18.56 |
| 2026-10-01 12:00 |
19:22:54.83 |
-16:05:56.2 |
HIP 95176 |
19.17 |
| 2026-10-02 00:00 |
19:22:56.54 |
-16:06:32.1 |
HIP 95176 |
19.80 |
| 2026-10-02 12:00 |
19:22:58.37 |
-16:07:07.6 |
HIP 95176 |
20.47 |
| 2026-10-03 00:00 |
19:23:00.34 |
-16:07:42.8 |
HIP 95323 |
20.93 |
| 2026-10-03 12:00 |
19:23:02.44 |
-16:08:17.7 |
HIP 95323 |
21.25 |
| 2026-10-04 00:00 |
19:23:04.68 |
-16:08:52.3 |
HIP 95323 |
21.59 |
| 2026-10-04 12:00 |
19:23:07.04 |
-16:09:26.5 |
HIP 95323 |
21.93 |
| 2026-10-05 00:00 |
19:23:09.54 |
-16:10:00.4 |
HIP 95323 |
22.27 |
| 2026-10-05 12:00 |
19:23:12.17 |
-16:10:34.1 |
HIP 95323 |
22.63 |
| 2026-10-06 00:00 |
19:23:14.93 |
-16:11:07.3 |
HIP 95323 |
23.01 |
| 2026-10-06 12:00 |
19:23:17.83 |
-16:11:40.3 |
HIP 95323 |
23.39 |
| 2026-10-07 00:00 |
19:23:20.86 |
-16:12:12.9 |
HIP 95323 |
23.80 |
| 2026-10-07 12:00 |
19:23:24.01 |
-16:12:45.2 |
HIP 95323 |
24.22 |
| 2026-10-08 00:00 |
19:23:27.30 |
-16:13:17.2 |
HIP 95323 |
24.66 |
| 2026-10-08 12:00 |
19:23:30.72 |
-16:13:48.9 |
HIP 95323 |
25.12 |
| 2026-10-09 00:00 |
19:23:34.28 |
-16:14:20.2 |
HIP 95323 |
25.61 |
| 2026-10-09 12:00 |
19:23:37.96 |
-16:14:51.1 |
HIP 95323 |
26.11 |
| 2026-10-10 00:00 |
19:23:41.77 |
-16:15:21.7 |
HIP 95323 |
26.65 |
| 2026-10-10 12:00 |
19:23:45.72 |
-16:15:52.0 |
HIP 95323 |
27.21 |
| 2026-10-11 00:00 |
19:23:49.79 |
-16:16:22.0 |
HIP 95323 |
27.80 |