メタデータ
| 項目 |
値 |
| Designation |
48P/Johnson |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-08-12T05:30:24.428160Z |
| Orbit solution date (soln_date, UTC) |
2026-07-07T05:51:27Z |
| Obs used |
2212 |
| NEO |
- |
| M1 |
9.100 |
| K1 |
16.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-03-22.0000000 |
| e |
0.42708734 |
| q (au) |
2.004539 |
| a (au) |
3.498855 |
| i (deg) |
12.207032 |
| Ω (om, deg) |
110.130729 |
| ω (w, deg) |
216.574526 |
| M (ma, deg) |
33.397883 |
等級
散乱 + 全体線形
$$
M_a = (8.552 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.552 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.874 |
| k |
0.999 |
| 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) |
| 2026-07-29 00:00 |
06:38:50.33 |
+20:03:50.3 |
HIP 31680 |
16.03 |
| 2026-07-29 12:00 |
06:39:25.05 |
+20:03:42.3 |
HIP 31680 |
24.15 |
| 2026-07-30 00:00 |
06:39:59.69 |
+20:03:33.9 |
HIP 32016 |
19.48 |
| 2026-07-30 12:00 |
06:40:34.25 |
+20:03:25.0 |
HIP 32016 |
11.86 |
| 2026-07-31 00:00 |
06:41:08.73 |
+20:03:15.6 |
HIP 32016 |
5.80 |
| 2026-07-31 12:00 |
06:41:43.13 |
+20:03:05.7 |
HIP 32016 |
7.58 |
| 2026-08-01 00:00 |
06:42:17.46 |
+20:02:55.4 |
HIP 32016 |
14.55 |
| 2026-08-01 12:00 |
06:42:51.71 |
+20:02:44.6 |
HIP 32016 |
22.25 |
| 2026-08-02 00:00 |
06:43:25.88 |
+20:02:33.4 |
HIP 32302 |
17.38 |
| 2026-08-02 12:00 |
06:43:59.97 |
+20:02:21.7 |
HIP 32302 |
9.57 |
| 2026-08-03 00:00 |
06:44:33.97 |
+20:02:09.6 |
HIP 32302 |
3.09 |
| 2026-08-03 12:00 |
06:45:07.90 |
+20:01:57.0 |
HIP 32302 |
7.41 |
| 2026-08-04 00:00 |
06:45:41.74 |
+20:01:44.0 |
HIP 32302 |
15.06 |
| 2026-08-04 12:00 |
06:46:15.50 |
+20:01:30.6 |
HIP 32302 |
22.89 |
| 2026-08-05 00:00 |
06:46:49.18 |
+20:01:16.7 |
HIP 32302 |
30.76 |
| 2026-08-05 12:00 |
06:47:22.77 |
+20:01:02.5 |
HIP 32302 |
38.63 |
| 2026-08-06 00:00 |
06:47:56.28 |
+20:00:47.8 |
HIP 32676 |
35.99 |
| 2026-08-06 12:00 |
06:48:29.70 |
+20:00:32.7 |
HIP 32852 |
33.04 |
| 2026-08-07 00:00 |
06:49:03.03 |
+20:00:17.2 |
HIP 32852 |
25.21 |
| 2026-08-07 12:00 |
06:49:36.28 |
+20:00:01.3 |
HIP 32852 |
17.39 |
| 2026-08-08 00:00 |
06:50:09.43 |
+19:59:45.0 |
HIP 32852 |
9.60 |
| 2026-08-08 12:00 |
06:50:42.50 |
+19:59:28.3 |
HIP 32852 |
1.83 |
| 2026-08-09 00:00 |
06:51:15.48 |
+19:59:11.2 |
HIP 32852 |
5.93 |
| 2026-08-09 12:00 |
06:51:48.37 |
+19:58:53.7 |
HIP 32852 |
13.66 |
| 2026-08-10 00:00 |
06:52:21.16 |
+19:58:35.9 |
HIP 32852 |
21.37 |
| 2026-08-10 12:00 |
06:52:53.86 |
+19:58:17.7 |
HIP 33026 |
24.18 |
| 2026-08-11 00:00 |
06:53:26.47 |
+19:57:59.2 |
HIP 33181 |
25.84 |
| 2026-08-11 12:00 |
06:53:58.99 |
+19:57:40.3 |
HIP 33181 |
22.62 |
| 2026-08-12 00:00 |
06:54:31.40 |
+19:57:21.0 |
HIP 33286 |
19.24 |
| 2026-08-12 12:00 |
06:55:03.72 |
+19:57:01.4 |
HIP 33286 |
15.50 |
| 2026-08-13 00:00 |
06:55:35.95 |
+19:56:41.5 |
HIP 33286 |
15.01 |
| 2026-08-13 12:00 |
06:56:08.07 |
+19:56:21.2 |
HIP 33286 |
18.03 |
| 2026-08-14 00:00 |
06:56:40.10 |
+19:56:00.6 |
HIP 33477 |
17.51 |
| 2026-08-14 12:00 |
06:57:12.02 |
+19:55:39.7 |
HIP 33477 |
12.91 |
| 2026-08-15 00:00 |
06:57:43.85 |
+19:55:18.5 |
HIP 33477 |
11.82 |
| 2026-08-15 12:00 |
06:58:15.57 |
+19:54:56.9 |
HIP 33477 |
14.98 |
| 2026-08-16 00:00 |
06:58:47.19 |
+19:54:35.1 |
HIP 33477 |
20.49 |
| 2026-08-16 12:00 |
06:59:18.71 |
+19:54:13.0 |
HIP 33477 |
26.92 |
| 2026-08-17 00:00 |
06:59:50.12 |
+19:53:50.6 |
HIP 33861 |
28.84 |
| 2026-08-17 12:00 |
07:00:21.43 |
+19:53:27.9 |
HIP 33861 |
22.19 |
| 2026-08-18 00:00 |
07:00:52.63 |
+19:53:04.9 |
HIP 33861 |
16.19 |
| 2026-08-18 12:00 |
07:01:23.72 |
+19:52:41.7 |
HIP 33861 |
11.83 |
| 2026-08-19 00:00 |
07:01:54.71 |
+19:52:18.2 |
HIP 33861 |
11.17 |