メタデータ
| 項目 |
値 |
| Designation |
12P/Pons-Brooks |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2024-04-21T03:08:52.180800Z |
| Orbit solution date (soln_date, UTC) |
2026-01-08T08:25:35Z |
| Obs used |
8059 |
| NEO |
Yes |
| M1 |
5.000 |
| K1 |
15.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2023-09-24.0000000 |
| e |
0.95456124 |
| q (au) |
0.780861 |
| a (au) |
17.184915 |
| i (deg) |
74.190910 |
| Ω (om, deg) |
255.855351 |
| ω (w, deg) |
198.987999 |
| M (ma, deg) |
357.092810 |
等級
散乱 + 全体線形
$$
M_a = (5.193 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.193 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.880 |
| k |
0.991 |
| 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 |
| 2020-06-10 |
2023-07-20 |
+7.5133 |
-5.467 |
| 2023-07-20 |
2023-08-30 |
-32.4270 |
+17.092 |
| 2023-08-30 |
2023-12-18 |
+0.8594 |
-0.954 |
| 2023-12-18 |
2024-04-20 |
-0.0616 |
+0.065 |
| 2024-04-21 |
2024-06-16 |
+0.4640 |
-0.450 |
| 2024-06-16 |
2024-10-11 |
-8.2592 |
+0.843 |
| 2024-10-11 |
2025-06-07 |
+15.5927 |
-9.537 |
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 |
17:08:14.23 |
-37:23:18.3 |
HIP 83789 |
10.25 |
| 2026-03-26 12:00 |
17:08:08.51 |
-37:23:31.5 |
HIP 83789 |
9.38 |
| 2026-03-27 00:00 |
17:08:02.61 |
-37:23:44.3 |
HIP 83789 |
8.55 |
| 2026-03-27 12:00 |
17:07:56.53 |
-37:23:56.8 |
HIP 83789 |
7.78 |
| 2026-03-28 00:00 |
17:07:50.28 |
-37:24:08.9 |
HIP 83789 |
7.12 |
| 2026-03-28 12:00 |
17:07:43.86 |
-37:24:20.7 |
HIP 83789 |
6.61 |
| 2026-03-29 00:00 |
17:07:37.26 |
-37:24:32.1 |
HIP 83789 |
6.31 |
| 2026-03-29 12:00 |
17:07:30.48 |
-37:24:43.2 |
HIP 83789 |
6.28 |
| 2026-03-30 00:00 |
17:07:23.53 |
-37:24:53.8 |
HIP 83789 |
6.53 |
| 2026-03-30 12:00 |
17:07:16.41 |
-37:25:04.1 |
HIP 83789 |
7.06 |
| 2026-03-31 00:00 |
17:07:09.11 |
-37:25:14.0 |
HIP 83789 |
7.83 |
| 2026-03-31 12:00 |
17:07:01.64 |
-37:25:23.6 |
HIP 83789 |
8.79 |
| 2026-04-01 00:00 |
17:06:54.00 |
-37:25:32.7 |
HIP 83789 |
9.91 |
| 2026-04-01 12:00 |
17:06:46.18 |
-37:25:41.4 |
HIP 83789 |
11.14 |
| 2026-04-02 00:00 |
17:06:38.20 |
-37:25:49.7 |
HIP 83789 |
12.47 |
| 2026-04-02 12:00 |
17:06:30.04 |
-37:25:57.6 |
HIP 83693 |
12.46 |
| 2026-04-03 00:00 |
17:06:21.71 |
-37:26:05.1 |
HIP 83693 |
12.44 |
| 2026-04-03 12:00 |
17:06:13.21 |
-37:26:12.1 |
HIP 83693 |
12.63 |
| 2026-04-04 00:00 |
17:06:04.54 |
-37:26:18.8 |
HIP 83693 |
13.04 |
| 2026-04-04 12:00 |
17:05:55.70 |
-37:26:24.9 |
HIP 83693 |
13.66 |
| 2026-04-05 00:00 |
17:05:46.69 |
-37:26:30.7 |
HIP 83693 |
14.48 |
| 2026-04-05 12:00 |
17:05:37.52 |
-37:26:35.9 |
HIP 83693 |
15.48 |
| 2026-04-06 00:00 |
17:05:28.17 |
-37:26:40.7 |
HIP 83693 |
16.63 |
| 2026-04-06 12:00 |
17:05:18.66 |
-37:26:45.1 |
HIP 83693 |
17.92 |
| 2026-04-07 00:00 |
17:05:08.99 |
-37:26:49.0 |
HIP 83693 |
19.33 |
| 2026-04-07 12:00 |
17:04:59.14 |
-37:26:52.4 |
HIP 83693 |
20.84 |
| 2026-04-08 00:00 |
17:04:49.13 |
-37:26:55.3 |
HIP 83418 |
21.39 |
| 2026-04-08 12:00 |
17:04:38.96 |
-37:26:57.7 |
HIP 83418 |
19.39 |
| 2026-04-09 00:00 |
17:04:28.62 |
-37:26:59.6 |
HIP 83418 |
17.37 |
| 2026-04-09 12:00 |
17:04:18.12 |
-37:27:01.0 |
HIP 83418 |
15.31 |
| 2026-04-10 00:00 |
17:04:07.46 |
-37:27:01.9 |
HIP 83418 |
13.23 |
| 2026-04-10 12:00 |
17:03:56.63 |
-37:27:02.3 |
HIP 83418 |
11.14 |
| 2026-04-11 00:00 |
17:03:45.65 |
-37:27:02.2 |
HIP 83418 |
9.03 |
| 2026-04-11 12:00 |
17:03:34.50 |
-37:27:01.5 |
HIP 83418 |
6.94 |
| 2026-04-12 00:00 |
17:03:23.19 |
-37:27:00.3 |
HIP 83418 |
4.93 |
| 2026-04-12 12:00 |
17:03:11.73 |
-37:26:58.5 |
HIP 83418 |
3.21 |
| 2026-04-13 00:00 |
17:03:00.11 |
-37:26:56.2 |
HIP 83418 |
2.58 |
| 2026-04-13 12:00 |
17:02:48.33 |
-37:26:53.4 |
HIP 83418 |
3.72 |
| 2026-04-14 00:00 |
17:02:36.39 |
-37:26:50.0 |
HIP 83418 |
5.67 |
| 2026-04-14 12:00 |
17:02:24.30 |
-37:26:46.0 |
HIP 83418 |
7.88 |
| 2026-04-15 00:00 |
17:02:12.06 |
-37:26:41.4 |
HIP 83340 |
9.22 |
| 2026-04-15 12:00 |
17:01:59.66 |
-37:26:36.3 |
HIP 83340 |
8.56 |
| 2026-04-16 00:00 |
17:01:47.11 |
-37:26:30.5 |
HIP 83340 |
8.58 |