メタデータ
| 項目 |
値 |
| Designation |
P/2019 X2 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2019-12-09T07:29:31.522560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:34:01Z |
| Obs used |
49 |
| NEO |
- |
| M1 |
18.100 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-12-04T13:53:07.584000Z |
| Discovery magnitude (MPC) |
21.60 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-12-28.0000000 |
| e |
0.49925561 |
| q (au) |
1.824131 |
| a (au) |
3.642840 |
| i (deg) |
15.881613 |
| Ω (om, deg) |
250.856818 |
| ω (w, deg) |
213.558832 |
| M (ma, deg) |
2.649128 |
等級
散乱 + 全体線形
$$
M_a = (20.000 + 3.550\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
20.000 |
| n |
3.550 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.936 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
02:05:29.96 |
+20:43:02.3 |
HIP 9815 |
13.14 |
| 2026-05-12 12:00 |
02:06:30.10 |
+20:46:53.2 |
HIP 9815 |
11.81 |
| 2026-05-13 00:00 |
02:07:30.34 |
+20:50:43.5 |
HIP 9815 |
23.07 |
| 2026-05-13 12:00 |
02:08:30.68 |
+20:54:33.2 |
HIP 9815 |
36.77 |
| 2026-05-14 00:00 |
02:09:31.14 |
+20:58:22.2 |
HIP 10216 |
29.00 |
| 2026-05-14 12:00 |
02:10:31.70 |
+21:02:10.5 |
HIP 10216 |
20.46 |
| 2026-05-15 00:00 |
02:11:32.37 |
+21:05:58.1 |
HIP 10218 |
16.82 |
| 2026-05-15 12:00 |
02:12:33.15 |
+21:09:44.9 |
HIP 10306 |
4.52 |
| 2026-05-16 00:00 |
02:13:34.03 |
+21:13:31.1 |
HIP 10306 |
10.77 |
| 2026-05-16 12:00 |
02:14:35.02 |
+21:17:16.5 |
HIP 10465 |
17.49 |
| 2026-05-17 00:00 |
02:15:36.12 |
+21:21:01.2 |
HIP 10465 |
22.88 |
| 2026-05-17 12:00 |
02:16:37.33 |
+21:24:45.1 |
HIP 10652 |
11.51 |
| 2026-05-18 00:00 |
02:17:38.64 |
+21:28:28.3 |
HIP 10652 |
9.23 |
| 2026-05-18 12:00 |
02:18:40.06 |
+21:32:10.6 |
HIP 10767 |
21.72 |
| 2026-05-19 00:00 |
02:19:41.59 |
+21:35:52.2 |
HIP 10801 |
20.72 |
| 2026-05-19 12:00 |
02:20:43.22 |
+21:39:32.9 |
HIP 10959 |
7.78 |
| 2026-05-20 00:00 |
02:21:44.96 |
+21:43:12.8 |
HIP 10959 |
11.06 |
| 2026-05-20 12:00 |
02:22:46.81 |
+21:46:51.8 |
HIP 10959 |
24.96 |
| 2026-05-21 00:00 |
02:23:48.76 |
+21:50:30.0 |
HIP 11315 |
26.19 |
| 2026-05-21 12:00 |
02:24:50.82 |
+21:54:07.4 |
HIP 11315 |
14.15 |
| 2026-05-22 00:00 |
02:25:52.98 |
+21:57:43.8 |
HIP 11315 |
12.49 |
| 2026-05-22 12:00 |
02:26:55.26 |
+22:01:19.3 |
HIP 11315 |
23.53 |
| 2026-05-23 00:00 |
02:27:57.64 |
+22:04:54.0 |
HIP 11584 |
34.64 |
| 2026-05-23 12:00 |
02:29:00.12 |
+22:08:27.7 |
HIP 11584 |
33.07 |
| 2026-05-24 00:00 |
02:30:02.72 |
+22:12:00.4 |
HIP 11728 |
20.02 |
| 2026-05-24 12:00 |
02:31:05.42 |
+22:15:32.3 |
HIP 11728 |
11.17 |
| 2026-05-25 00:00 |
02:32:08.23 |
+22:19:03.1 |
HIP 11814 |
3.55 |
| 2026-05-25 12:00 |
02:33:11.15 |
+22:22:33.0 |
HIP 11814 |
11.42 |
| 2026-05-26 00:00 |
02:34:14.17 |
+22:26:01.9 |
HIP 12017 |
10.89 |
| 2026-05-26 12:00 |
02:35:17.31 |
+22:29:29.8 |
HIP 12017 |
4.16 |
| 2026-05-27 00:00 |
02:36:20.55 |
+22:32:56.7 |
HIP 12017 |
19.14 |
| 2026-05-27 12:00 |
02:37:23.90 |
+22:36:22.6 |
HIP 12159 |
28.49 |
| 2026-05-28 00:00 |
02:38:27.36 |
+22:39:47.5 |
HIP 12257 |
29.27 |
| 2026-05-28 12:00 |
02:39:30.92 |
+22:43:11.3 |
HIP 12257 |
33.90 |
| 2026-05-29 00:00 |
02:40:34.60 |
+22:46:34.0 |
HIP 12665 |
34.16 |
| 2026-05-29 12:00 |
02:41:38.39 |
+22:49:55.7 |
HIP 12665 |
20.18 |
| 2026-05-30 00:00 |
02:42:42.28 |
+22:53:16.3 |
HIP 12665 |
10.12 |
| 2026-05-30 12:00 |
02:43:46.29 |
+22:56:35.8 |
HIP 12665 |
15.92 |
| 2026-05-31 00:00 |
02:44:50.40 |
+22:59:54.2 |
HIP 12830 |
22.22 |
| 2026-05-31 12:00 |
02:45:54.62 |
+23:03:11.4 |
HIP 13012 |
19.40 |
| 2026-06-01 00:00 |
02:46:58.96 |
+23:06:27.6 |
HIP 13012 |
9.61 |
| 2026-06-01 12:00 |
02:48:03.40 |
+23:09:42.6 |
HIP 13012 |
16.37 |
| 2026-06-02 00:00 |
02:49:07.96 |
+23:12:56.4 |
HIP 13012 |
30.08 |