メタデータ
| 項目 |
値 |
| Designation |
17P/Holmes |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-03-26T17:17:14.196480Z |
| Orbit solution date (soln_date, UTC) |
2023-10-10T13:05:23Z |
| Obs used |
2211 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
14.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2016-10-19.0000000 |
| e |
0.43015482 |
| q (au) |
2.066329 |
| a (au) |
3.626124 |
| i (deg) |
19.070359 |
| Ω (om, deg) |
326.773810 |
| ω (w, deg) |
24.738506 |
| M (ma, deg) |
133.785581 |
等級
散乱 + 全体線形
$$
M_a = (8.460 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.460 |
| 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 |
| 2019-01-17 |
2021-07-29 |
-14.8750 |
+4.940 |
| 2021-07-29 |
2021-10-22 |
+35.1628 |
-14.605 |
| 2021-10-22 |
2022-01-30 |
-23.8751 |
+11.231 |
| 2022-01-30 |
2023-01-22 |
+4.5697 |
-3.280 |
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 |
13:57:32.98 |
-35:02:22.9 |
HIP 68151 |
9.58 |
| 2026-03-26 12:00 |
13:57:13.83 |
-35:03:08.1 |
HIP 68151 |
8.98 |
| 2026-03-27 00:00 |
13:56:54.48 |
-35:03:51.3 |
HIP 68151 |
10.04 |
| 2026-03-27 12:00 |
13:56:34.92 |
-35:04:32.2 |
HIP 68151 |
12.39 |
| 2026-03-28 00:00 |
13:56:15.16 |
-35:05:11.0 |
HIP 68151 |
15.46 |
| 2026-03-28 12:00 |
13:55:55.19 |
-35:05:47.6 |
HIP 68151 |
18.94 |
| 2026-03-29 00:00 |
13:55:35.04 |
-35:06:22.0 |
HIP 68151 |
22.65 |
| 2026-03-29 12:00 |
13:55:14.69 |
-35:06:54.2 |
HIP 67895 |
20.18 |
| 2026-03-30 00:00 |
13:54:54.15 |
-35:07:24.2 |
HIP 67851 |
17.05 |
| 2026-03-30 12:00 |
13:54:33.43 |
-35:07:52.0 |
HIP 67851 |
13.83 |
| 2026-03-31 00:00 |
13:54:12.52 |
-35:08:17.6 |
HIP 67851 |
11.34 |
| 2026-03-31 12:00 |
13:53:51.44 |
-35:08:40.9 |
HIP 67851 |
10.17 |
| 2026-04-01 00:00 |
13:53:30.17 |
-35:09:02.0 |
HIP 67851 |
10.81 |
| 2026-04-01 12:00 |
13:53:08.74 |
-35:09:20.8 |
HIP 67738 |
8.87 |
| 2026-04-02 00:00 |
13:52:47.13 |
-35:09:37.3 |
HIP 67738 |
6.10 |
| 2026-04-02 12:00 |
13:52:25.36 |
-35:09:51.6 |
HIP 67738 |
5.87 |
| 2026-04-03 00:00 |
13:52:03.43 |
-35:10:03.6 |
HIP 67738 |
8.45 |
| 2026-04-03 12:00 |
13:51:41.34 |
-35:10:13.3 |
HIP 67738 |
12.20 |
| 2026-04-04 00:00 |
13:51:19.09 |
-35:10:20.6 |
HIP 67738 |
16.36 |
| 2026-04-04 12:00 |
13:50:56.69 |
-35:10:25.7 |
HIP 67539 |
13.43 |
| 2026-04-05 00:00 |
13:50:34.15 |
-35:10:28.5 |
HIP 67539 |
11.48 |
| 2026-04-05 12:00 |
13:50:11.46 |
-35:10:29.0 |
HIP 67539 |
11.25 |
| 2026-04-06 00:00 |
13:49:48.63 |
-35:10:27.1 |
HIP 67539 |
12.86 |
| 2026-04-06 12:00 |
13:49:25.66 |
-35:10:22.9 |
HIP 67539 |
15.79 |
| 2026-04-07 00:00 |
13:49:02.56 |
-35:10:16.4 |
HIP 67539 |
19.46 |
| 2026-04-07 12:00 |
13:48:39.33 |
-35:10:07.5 |
HIP 67539 |
23.55 |
| 2026-04-08 00:00 |
13:48:15.98 |
-35:09:56.4 |
HIP 67191 |
25.59 |
| 2026-04-08 12:00 |
13:47:52.51 |
-35:09:42.8 |
HIP 67191 |
20.80 |
| 2026-04-09 00:00 |
13:47:28.93 |
-35:09:26.9 |
HIP 67191 |
16.00 |
| 2026-04-09 12:00 |
13:47:05.23 |
-35:09:08.7 |
HIP 67191 |
11.20 |
| 2026-04-10 00:00 |
13:46:41.42 |
-35:08:48.1 |
HIP 67191 |
6.46 |
| 2026-04-10 12:00 |
13:46:17.51 |
-35:08:25.2 |
HIP 67191 |
2.38 |
| 2026-04-11 00:00 |
13:45:53.51 |
-35:08:00.0 |
HIP 67191 |
4.25 |
| 2026-04-11 12:00 |
13:45:29.41 |
-35:07:32.3 |
HIP 67191 |
8.91 |
| 2026-04-12 00:00 |
13:45:05.22 |
-35:07:02.4 |
HIP 67191 |
13.80 |
| 2026-04-12 12:00 |
13:44:40.95 |
-35:06:30.1 |
HIP 67012 |
14.99 |
| 2026-04-13 00:00 |
13:44:16.59 |
-35:05:55.4 |
HIP 67012 |
13.52 |
| 2026-04-13 12:00 |
13:43:52.17 |
-35:05:18.5 |
HIP 67012 |
13.87 |
| 2026-04-14 00:00 |
13:43:27.67 |
-35:04:39.2 |
HIP 66942 |
13.12 |
| 2026-04-14 12:00 |
13:43:03.10 |
-35:03:57.5 |
HIP 66942 |
13.60 |
| 2026-04-15 00:00 |
13:42:38.48 |
-35:03:13.6 |
HIP 66942 |
15.83 |
| 2026-04-15 12:00 |
13:42:13.80 |
-35:02:27.3 |
HIP 66835 |
16.33 |
| 2026-04-16 00:00 |
13:41:49.06 |
-35:01:38.8 |
HIP 66835 |
14.89 |