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 |
-0.500 |
| 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) |
| 2026-09-20 00:00 |
09:43:56.55 |
-49:53:34.8 |
HIP 47824 |
11.52 |
| 2026-09-20 12:00 |
09:44:02.85 |
-49:54:34.5 |
HIP 47824 |
10.11 |
| 2026-09-21 00:00 |
09:44:09.12 |
-49:55:34.7 |
HIP 47824 |
8.70 |
| 2026-09-21 12:00 |
09:44:15.34 |
-49:56:35.3 |
HIP 47824 |
7.30 |
| 2026-09-22 00:00 |
09:44:21.53 |
-49:57:36.4 |
HIP 47824 |
5.92 |
| 2026-09-22 12:00 |
09:44:27.67 |
-49:58:37.9 |
HIP 47824 |
4.56 |
| 2026-09-23 00:00 |
09:44:33.78 |
-49:59:39.9 |
HIP 47824 |
3.27 |
| 2026-09-23 12:00 |
09:44:39.84 |
-50:00:42.3 |
HIP 47824 |
2.16 |
| 2026-09-24 00:00 |
09:44:45.86 |
-50:01:45.2 |
HIP 47824 |
1.65 |
| 2026-09-24 12:00 |
09:44:51.84 |
-50:02:48.6 |
HIP 47824 |
2.21 |
| 2026-09-25 00:00 |
09:44:57.78 |
-50:03:52.4 |
HIP 47824 |
3.34 |
| 2026-09-25 12:00 |
09:45:03.67 |
-50:04:56.6 |
HIP 47824 |
4.64 |
| 2026-09-26 00:00 |
09:45:09.53 |
-50:06:01.2 |
HIP 47824 |
6.01 |
| 2026-09-26 12:00 |
09:45:15.33 |
-50:07:06.3 |
HIP 47824 |
7.40 |
| 2026-09-27 00:00 |
09:45:21.10 |
-50:08:11.8 |
HIP 47824 |
8.80 |
| 2026-09-27 12:00 |
09:45:26.82 |
-50:09:17.7 |
HIP 47824 |
10.22 |
| 2026-09-28 00:00 |
09:45:32.49 |
-50:10:24.1 |
HIP 47824 |
11.64 |
| 2026-09-28 12:00 |
09:45:38.12 |
-50:11:30.9 |
HIP 47824 |
13.06 |
| 2026-09-29 00:00 |
09:45:43.71 |
-50:12:38.1 |
HIP 47824 |
14.49 |
| 2026-09-29 12:00 |
09:45:49.25 |
-50:13:45.7 |
HIP 47989 |
13.81 |
| 2026-09-30 00:00 |
09:45:54.74 |
-50:14:53.7 |
HIP 47989 |
12.40 |
| 2026-09-30 12:00 |
09:46:00.18 |
-50:16:02.1 |
HIP 47989 |
10.99 |
| 2026-10-01 00:00 |
09:46:05.58 |
-50:17:10.9 |
HIP 47989 |
9.59 |
| 2026-10-01 12:00 |
09:46:10.93 |
-50:18:20.1 |
HIP 47989 |
8.20 |
| 2026-10-02 00:00 |
09:46:16.23 |
-50:19:29.7 |
HIP 47989 |
6.84 |
| 2026-10-02 12:00 |
09:46:21.48 |
-50:20:39.7 |
HIP 47989 |
5.52 |
| 2026-10-03 00:00 |
09:46:26.69 |
-50:21:50.1 |
HIP 47989 |
4.28 |
| 2026-10-03 12:00 |
09:46:31.84 |
-50:23:00.8 |
HIP 47989 |
3.21 |
| 2026-10-04 00:00 |
09:46:36.94 |
-50:24:12.0 |
HIP 47989 |
2.56 |
| 2026-10-04 12:00 |
09:46:42.00 |
-50:25:23.5 |
HIP 47989 |
2.64 |
| 2026-10-05 00:00 |
09:46:47.00 |
-50:26:35.4 |
HIP 47989 |
3.40 |
| 2026-10-05 12:00 |
09:46:51.94 |
-50:27:47.6 |
HIP 47989 |
4.51 |
| 2026-10-06 00:00 |
09:46:56.84 |
-50:29:00.3 |
HIP 47989 |
5.78 |
| 2026-10-06 12:00 |
09:47:01.68 |
-50:30:13.3 |
HIP 47989 |
7.11 |
| 2026-10-07 00:00 |
09:47:06.47 |
-50:31:26.6 |
HIP 47989 |
8.48 |
| 2026-10-07 12:00 |
09:47:11.21 |
-50:32:40.3 |
HIP 47989 |
9.88 |
| 2026-10-08 00:00 |
09:47:15.89 |
-50:33:54.3 |
HIP 47989 |
11.29 |
| 2026-10-08 12:00 |
09:47:20.52 |
-50:35:08.7 |
HIP 47989 |
12.70 |
| 2026-10-09 00:00 |
09:47:25.09 |
-50:36:23.4 |
HIP 47989 |
14.13 |
| 2026-10-09 12:00 |
09:47:29.61 |
-50:37:38.5 |
HIP 47989 |
15.56 |
| 2026-10-10 00:00 |
09:47:34.07 |
-50:38:53.8 |
HIP 48185 |
16.79 |
| 2026-10-10 12:00 |
09:47:38.47 |
-50:40:09.5 |
HIP 48185 |
16.09 |
| 2026-10-11 00:00 |
09:47:42.81 |
-50:41:25.5 |
HIP 48185 |
15.50 |