メタデータ
| 項目 |
値 |
| Designation |
C/2019 J2 (Palomar) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-07-19T17:09:39.836160Z |
| Orbit solution date (soln_date, UTC) |
2021-09-04T23:42:59Z |
| Obs used |
312 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
22.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2019-05-09T11:22:13.987200Z |
| Discovery magnitude (MPC) |
16.86 r |
| Discovery observatory (MPC) |
I41 · Palomar Mountain–ZTF |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-06-10.0000000 |
| e |
0.99767395 |
| q (au) |
1.727002 |
| a (au) |
742.459732 |
| i (deg) |
105.135744 |
| Ω (om, deg) |
25.468130 |
| ω (w, deg) |
98.695628 |
| M (ma, deg) |
359.998065 |
等級
散乱 + 全体線形
$$
M_a = (10.283 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.283 |
| 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 |
| 2019-04-27 |
2019-07-19 |
-32.7489 |
+9.328 |
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 |
09:25:52.70 |
-53:23:12.5 |
HIP 46283 |
3.80 |
| 2026-03-26 12:00 |
09:25:44.31 |
-53:22:00.5 |
HIP 46283 |
5.07 |
| 2026-03-27 00:00 |
09:25:36.00 |
-53:20:48.0 |
HIP 46236 |
5.70 |
| 2026-03-27 12:00 |
09:25:27.76 |
-53:19:35.1 |
HIP 46236 |
4.67 |
| 2026-03-28 00:00 |
09:25:19.60 |
-53:18:21.7 |
HIP 46236 |
4.11 |
| 2026-03-28 12:00 |
09:25:11.52 |
-53:17:07.8 |
HIP 46236 |
4.23 |
| 2026-03-29 00:00 |
09:25:03.52 |
-53:15:53.5 |
HIP 46236 |
4.97 |
| 2026-03-29 12:00 |
09:24:55.60 |
-53:14:38.7 |
HIP 46236 |
6.11 |
| 2026-03-30 00:00 |
09:24:47.75 |
-53:13:23.5 |
HIP 46236 |
7.47 |
| 2026-03-30 12:00 |
09:24:39.99 |
-53:12:07.9 |
HIP 46236 |
8.94 |
| 2026-03-31 00:00 |
09:24:32.31 |
-53:10:51.8 |
HIP 46074 |
8.96 |
| 2026-03-31 12:00 |
09:24:24.71 |
-53:09:35.3 |
HIP 46074 |
8.99 |
| 2026-04-01 00:00 |
09:24:17.19 |
-53:08:18.4 |
HIP 46074 |
9.35 |
| 2026-04-01 12:00 |
09:24:09.75 |
-53:07:01.1 |
HIP 46074 |
10.00 |
| 2026-04-02 00:00 |
09:24:02.40 |
-53:05:43.4 |
HIP 46074 |
10.89 |
| 2026-04-02 12:00 |
09:23:55.13 |
-53:04:25.3 |
HIP 46074 |
11.97 |
| 2026-04-03 00:00 |
09:23:47.93 |
-53:03:06.8 |
HIP 46020 |
11.71 |
| 2026-04-03 12:00 |
09:23:40.83 |
-53:01:48.0 |
HIP 46020 |
10.03 |
| 2026-04-04 00:00 |
09:23:33.80 |
-53:00:28.8 |
HIP 46020 |
8.36 |
| 2026-04-04 12:00 |
09:23:26.86 |
-52:59:09.2 |
HIP 46020 |
6.70 |
| 2026-04-05 00:00 |
09:23:20.01 |
-52:57:49.3 |
HIP 46020 |
5.06 |
| 2026-04-05 12:00 |
09:23:13.23 |
-52:56:29.0 |
HIP 46020 |
3.46 |
| 2026-04-06 00:00 |
09:23:06.55 |
-52:55:08.4 |
HIP 46020 |
1.99 |
| 2026-04-06 12:00 |
09:22:59.94 |
-52:53:47.4 |
HIP 46020 |
1.26 |
| 2026-04-07 00:00 |
09:22:53.43 |
-52:52:26.2 |
HIP 46020 |
2.19 |
| 2026-04-07 12:00 |
09:22:46.99 |
-52:51:04.6 |
HIP 46020 |
3.68 |
| 2026-04-08 00:00 |
09:22:40.65 |
-52:49:42.7 |
HIP 46020 |
5.27 |
| 2026-04-08 12:00 |
09:22:34.39 |
-52:48:20.5 |
HIP 46020 |
6.89 |
| 2026-04-09 00:00 |
09:22:28.21 |
-52:46:58.0 |
HIP 46032 |
7.78 |
| 2026-04-09 12:00 |
09:22:22.13 |
-52:45:35.2 |
HIP 46032 |
8.44 |
| 2026-04-10 00:00 |
09:22:16.12 |
-52:44:12.2 |
HIP 46032 |
9.35 |
| 2026-04-10 12:00 |
09:22:10.21 |
-52:42:48.9 |
HIP 46032 |
10.43 |
| 2026-04-11 00:00 |
09:22:04.38 |
-52:41:25.3 |
HIP 46032 |
11.63 |
| 2026-04-11 12:00 |
09:21:58.65 |
-52:40:01.4 |
HIP 46032 |
12.92 |
| 2026-04-12 00:00 |
09:21:52.99 |
-52:38:37.3 |
HIP 46032 |
14.28 |
| 2026-04-12 12:00 |
09:21:47.43 |
-52:37:13.0 |
HIP 45808 |
13.02 |
| 2026-04-13 00:00 |
09:21:41.96 |
-52:35:48.5 |
HIP 45808 |
11.77 |
| 2026-04-13 12:00 |
09:21:36.57 |
-52:34:23.7 |
HIP 45808 |
10.65 |
| 2026-04-14 00:00 |
09:21:31.27 |
-52:32:58.7 |
HIP 45808 |
9.68 |
| 2026-04-14 12:00 |
09:21:26.06 |
-52:31:33.5 |
HIP 45808 |
8.93 |
| 2026-04-15 00:00 |
09:21:20.94 |
-52:30:08.1 |
HIP 45808 |
8.43 |
| 2026-04-15 12:00 |
09:21:15.91 |
-52:28:42.5 |
HIP 45808 |
8.25 |
| 2026-04-16 00:00 |
09:21:10.97 |
-52:27:16.7 |
HIP 45808 |
8.39 |