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) |
| 2026-05-12 00:00 |
09:18:56.39 |
-51:11:57.2 |
HIP 45631 |
11.92 |
| 2026-05-12 12:00 |
09:18:56.10 |
-51:10:32.5 |
HIP 45631 |
10.87 |
| 2026-05-13 00:00 |
09:18:55.89 |
-51:09:08.1 |
HIP 45631 |
9.93 |
| 2026-05-13 12:00 |
09:18:55.76 |
-51:07:43.8 |
HIP 45631 |
9.12 |
| 2026-05-14 00:00 |
09:18:55.71 |
-51:06:19.8 |
HIP 45631 |
8.48 |
| 2026-05-14 12:00 |
09:18:55.75 |
-51:04:56.0 |
HIP 45631 |
8.06 |
| 2026-05-15 00:00 |
09:18:55.87 |
-51:03:32.5 |
HIP 45631 |
7.87 |
| 2026-05-15 12:00 |
09:18:56.07 |
-51:02:09.1 |
HIP 45631 |
7.94 |
| 2026-05-16 00:00 |
09:18:56.35 |
-51:00:46.0 |
HIP 45631 |
8.26 |
| 2026-05-16 12:00 |
09:18:56.72 |
-50:59:23.2 |
HIP 45631 |
8.79 |
| 2026-05-17 00:00 |
09:18:57.16 |
-50:58:00.6 |
HIP 45631 |
9.51 |
| 2026-05-17 12:00 |
09:18:57.69 |
-50:56:38.3 |
HIP 45631 |
10.37 |
| 2026-05-18 00:00 |
09:18:58.29 |
-50:55:16.3 |
HIP 45631 |
11.34 |
| 2026-05-18 12:00 |
09:18:58.98 |
-50:53:54.5 |
HIP 45631 |
12.39 |
| 2026-05-19 00:00 |
09:18:59.75 |
-50:52:33.1 |
HIP 45631 |
13.50 |
| 2026-05-19 12:00 |
09:19:00.59 |
-50:51:11.9 |
HIP 45631 |
14.66 |
| 2026-05-20 00:00 |
09:19:01.52 |
-50:49:51.0 |
HIP 45631 |
15.85 |
| 2026-05-20 12:00 |
09:19:02.52 |
-50:48:30.4 |
HIP 45631 |
17.07 |
| 2026-05-21 00:00 |
09:19:03.60 |
-50:47:10.2 |
HIP 45765 |
16.68 |
| 2026-05-21 12:00 |
09:19:04.76 |
-50:45:50.2 |
HIP 45765 |
15.45 |
| 2026-05-22 00:00 |
09:19:06.00 |
-50:44:30.6 |
HIP 45765 |
14.24 |
| 2026-05-22 12:00 |
09:19:07.31 |
-50:43:11.3 |
HIP 45765 |
13.05 |
| 2026-05-23 00:00 |
09:19:08.70 |
-50:41:52.3 |
HIP 45765 |
11.89 |
| 2026-05-23 12:00 |
09:19:10.17 |
-50:40:33.6 |
HIP 45765 |
10.76 |
| 2026-05-24 00:00 |
09:19:11.71 |
-50:39:15.3 |
HIP 45765 |
9.68 |
| 2026-05-24 12:00 |
09:19:13.33 |
-50:37:57.4 |
HIP 45765 |
8.66 |
| 2026-05-25 00:00 |
09:19:15.02 |
-50:36:39.8 |
HIP 45765 |
7.73 |
| 2026-05-25 12:00 |
09:19:16.78 |
-50:35:22.5 |
HIP 45765 |
6.92 |
| 2026-05-26 00:00 |
09:19:18.62 |
-50:34:05.6 |
HIP 45765 |
6.27 |
| 2026-05-26 12:00 |
09:19:20.54 |
-50:32:49.1 |
HIP 45765 |
5.84 |
| 2026-05-27 00:00 |
09:19:22.53 |
-50:31:33.0 |
HIP 45765 |
5.66 |
| 2026-05-27 12:00 |
09:19:24.59 |
-50:30:17.2 |
HIP 45765 |
5.78 |
| 2026-05-28 00:00 |
09:19:26.72 |
-50:29:01.8 |
HIP 45765 |
6.16 |
| 2026-05-28 12:00 |
09:19:28.92 |
-50:27:46.8 |
HIP 45765 |
6.76 |
| 2026-05-29 00:00 |
09:19:31.20 |
-50:26:32.2 |
HIP 45765 |
7.53 |
| 2026-05-29 12:00 |
09:19:33.54 |
-50:25:17.9 |
HIP 45765 |
8.41 |
| 2026-05-30 00:00 |
09:19:35.96 |
-50:24:04.1 |
HIP 45765 |
9.38 |
| 2026-05-30 12:00 |
09:19:38.45 |
-50:22:50.7 |
HIP 45765 |
10.41 |
| 2026-05-31 00:00 |
09:19:41.01 |
-50:21:37.6 |
HIP 45765 |
11.48 |
| 2026-05-31 12:00 |
09:19:43.63 |
-50:20:25.0 |
HIP 45765 |
12.59 |
| 2026-06-01 00:00 |
09:19:46.33 |
-50:19:12.8 |
HIP 45765 |
13.71 |
| 2026-06-01 12:00 |
09:19:49.10 |
-50:18:01.1 |
HIP 45765 |
14.86 |
| 2026-06-02 00:00 |
09:19:51.93 |
-50:16:49.7 |
HIP 45765 |
16.01 |