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
$$
M_a = (10.764 + 3.368\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.764 |
| n |
3.368 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
4.853 |
| 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) |
| 2026-03-26 00:00 |
19:52:28.45 |
-13:49:12.5 |
HIP 97618 |
30.21 |
| 2026-03-26 12:00 |
19:52:38.07 |
-13:48:35.6 |
HIP 97618 |
32.63 |
| 2026-03-27 00:00 |
19:52:47.59 |
-13:47:58.9 |
HIP 98014 |
33.44 |
| 2026-03-27 12:00 |
19:52:57.01 |
-13:47:22.4 |
HIP 98014 |
31.14 |
| 2026-03-28 00:00 |
19:53:06.32 |
-13:46:46.1 |
HIP 98014 |
28.88 |
| 2026-03-28 12:00 |
19:53:15.54 |
-13:46:09.9 |
HIP 98014 |
26.65 |
| 2026-03-29 00:00 |
19:53:24.65 |
-13:45:33.8 |
HIP 98014 |
24.47 |
| 2026-03-29 12:00 |
19:53:33.66 |
-13:44:58.0 |
HIP 98014 |
22.33 |
| 2026-03-30 00:00 |
19:53:42.56 |
-13:44:22.3 |
HIP 98014 |
20.25 |
| 2026-03-30 12:00 |
19:53:51.36 |
-13:43:46.8 |
HIP 98014 |
18.23 |
| 2026-03-31 00:00 |
19:54:00.06 |
-13:43:11.5 |
HIP 98014 |
16.28 |
| 2026-03-31 12:00 |
19:54:08.65 |
-13:42:36.3 |
HIP 98014 |
14.43 |
| 2026-04-01 00:00 |
19:54:17.14 |
-13:42:01.4 |
HIP 98014 |
12.70 |
| 2026-04-01 12:00 |
19:54:25.52 |
-13:41:26.6 |
HIP 98014 |
11.14 |
| 2026-04-02 00:00 |
19:54:33.80 |
-13:40:52.1 |
HIP 98014 |
9.80 |
| 2026-04-02 12:00 |
19:54:41.97 |
-13:40:17.7 |
HIP 98014 |
8.77 |
| 2026-04-03 00:00 |
19:54:50.03 |
-13:39:43.5 |
HIP 98014 |
8.16 |
| 2026-04-03 12:00 |
19:54:57.98 |
-13:39:09.6 |
HIP 98014 |
8.04 |
| 2026-04-04 00:00 |
19:55:05.83 |
-13:38:35.8 |
HIP 98014 |
8.41 |
| 2026-04-04 12:00 |
19:55:13.57 |
-13:38:02.3 |
HIP 98014 |
9.19 |
| 2026-04-05 00:00 |
19:55:21.20 |
-13:37:28.9 |
HIP 98014 |
10.28 |
| 2026-04-05 12:00 |
19:55:28.72 |
-13:36:55.8 |
HIP 98014 |
11.57 |
| 2026-04-06 00:00 |
19:55:36.13 |
-13:36:22.9 |
HIP 98014 |
13.00 |
| 2026-04-06 12:00 |
19:55:43.43 |
-13:35:50.3 |
HIP 98014 |
14.51 |
| 2026-04-07 00:00 |
19:55:50.61 |
-13:35:17.9 |
HIP 98109 |
15.77 |
| 2026-04-07 12:00 |
19:55:57.69 |
-13:34:45.7 |
HIP 98109 |
14.64 |
| 2026-04-08 00:00 |
19:56:04.66 |
-13:34:13.7 |
HIP 98109 |
13.67 |
| 2026-04-08 12:00 |
19:56:11.51 |
-13:33:42.0 |
HIP 98109 |
12.88 |
| 2026-04-09 00:00 |
19:56:18.25 |
-13:33:10.5 |
HIP 98109 |
12.29 |
| 2026-04-09 12:00 |
19:56:24.88 |
-13:32:39.3 |
HIP 98109 |
11.93 |
| 2026-04-10 00:00 |
19:56:31.39 |
-13:32:08.3 |
HIP 98109 |
11.79 |
| 2026-04-10 12:00 |
19:56:37.79 |
-13:31:37.6 |
HIP 98109 |
11.88 |
| 2026-04-11 00:00 |
19:56:44.07 |
-13:31:07.2 |
HIP 98109 |
12.18 |
| 2026-04-11 12:00 |
19:56:50.24 |
-13:30:37.0 |
HIP 98109 |
12.66 |
| 2026-04-12 00:00 |
19:56:56.29 |
-13:30:07.1 |
HIP 98109 |
13.30 |
| 2026-04-12 12:00 |
19:57:02.23 |
-13:29:37.4 |
HIP 98109 |
14.06 |
| 2026-04-13 00:00 |
19:57:08.05 |
-13:29:08.0 |
HIP 98109 |
14.92 |
| 2026-04-13 12:00 |
19:57:13.75 |
-13:28:39.0 |
HIP 98109 |
15.85 |
| 2026-04-14 00:00 |
19:57:19.34 |
-13:28:10.1 |
HIP 98109 |
16.84 |
| 2026-04-14 12:00 |
19:57:24.81 |
-13:27:41.6 |
HIP 98109 |
17.86 |
| 2026-04-15 00:00 |
19:57:30.15 |
-13:27:13.4 |
HIP 98109 |
18.91 |
| 2026-04-15 12:00 |
19:57:35.39 |
-13:26:45.5 |
HIP 98109 |
19.97 |
| 2026-04-16 00:00 |
19:57:40.50 |
-13:26:17.8 |
HIP 98352 |
20.31 |