メタデータ
| 項目 |
値 |
| Designation |
161P/Hartley-IRAS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2005-06-20T20:24:46.189440Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:27:43Z |
| Obs used |
335 |
| NEO |
Yes |
| M1 |
11.500 |
| K1 |
11.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2004-07-04.0000000 |
| e |
0.83508810 |
| q (au) |
1.274829 |
| a (au) |
7.730366 |
| i (deg) |
95.698050 |
| Ω (om, deg) |
1.398165 |
| ω (w, deg) |
47.091452 |
| M (ma, deg) |
343.865252 |
等級
散乱 + 全体線形
$$
M_a = (9.254 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
9.254 |
| 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
ファインディングチャート
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
02:03:52.45 |
-39:44:56.1 |
HIP 9539 |
24.54 |
| 2026-03-26 12:00 |
02:04:10.83 |
-39:36:58.1 |
HIP 9539 |
21.63 |
| 2026-03-27 00:00 |
02:04:29.31 |
-39:29:01.6 |
HIP 9812 |
20.53 |
| 2026-03-27 12:00 |
02:04:47.89 |
-39:21:06.6 |
HIP 9812 |
20.12 |
| 2026-03-28 00:00 |
02:05:06.57 |
-39:13:13.0 |
HIP 9812 |
23.17 |
| 2026-03-28 12:00 |
02:05:25.36 |
-39:05:21.0 |
HIP 9812 |
28.60 |
| 2026-03-29 00:00 |
02:05:44.24 |
-38:57:30.4 |
HIP 9812 |
35.31 |
| 2026-03-29 12:00 |
02:06:03.22 |
-38:49:41.3 |
HIP 10052 |
40.37 |
| 2026-03-30 00:00 |
02:06:22.30 |
-38:41:53.6 |
HIP 10052 |
39.80 |
| 2026-03-30 12:00 |
02:06:41.47 |
-38:34:07.5 |
HIP 10052 |
41.04 |
| 2026-03-31 00:00 |
02:07:00.74 |
-38:26:22.8 |
HIP 9806 |
38.95 |
| 2026-03-31 12:00 |
02:07:20.09 |
-38:18:39.6 |
HIP 9806 |
32.94 |
| 2026-04-01 00:00 |
02:07:39.54 |
-38:10:57.9 |
HIP 9806 |
28.33 |
| 2026-04-01 12:00 |
02:07:59.08 |
-38:03:17.6 |
HIP 9806 |
25.89 |
| 2026-04-02 00:00 |
02:08:18.70 |
-37:55:38.9 |
HIP 9806 |
26.21 |
| 2026-04-02 12:00 |
02:08:38.41 |
-37:48:01.7 |
HIP 9806 |
29.19 |
| 2026-04-03 00:00 |
02:08:58.21 |
-37:40:25.9 |
HIP 10110 |
21.96 |
| 2026-04-03 12:00 |
02:09:18.09 |
-37:32:51.6 |
HIP 10110 |
13.61 |
| 2026-04-04 00:00 |
02:09:38.05 |
-37:25:18.8 |
HIP 10110 |
5.79 |
| 2026-04-04 12:00 |
02:09:58.10 |
-37:17:47.5 |
HIP 10110 |
5.17 |
| 2026-04-05 00:00 |
02:10:18.22 |
-37:10:17.7 |
HIP 10110 |
12.82 |
| 2026-04-05 12:00 |
02:10:38.43 |
-37:02:49.4 |
HIP 10123 |
17.31 |
| 2026-04-06 00:00 |
02:10:58.71 |
-36:55:22.6 |
HIP 10123 |
12.88 |
| 2026-04-06 12:00 |
02:11:19.07 |
-36:47:57.4 |
HIP 10123 |
13.30 |
| 2026-04-07 00:00 |
02:11:39.51 |
-36:40:33.6 |
HIP 10123 |
18.22 |
| 2026-04-07 12:00 |
02:12:00.02 |
-36:33:11.3 |
HIP 10343 |
17.29 |
| 2026-04-08 00:00 |
02:12:20.60 |
-36:25:50.5 |
HIP 10343 |
10.99 |
| 2026-04-08 12:00 |
02:12:41.26 |
-36:18:31.2 |
HIP 10343 |
9.15 |
| 2026-04-09 00:00 |
02:13:01.98 |
-36:11:13.5 |
HIP 10347 |
8.21 |
| 2026-04-09 12:00 |
02:13:22.78 |
-36:03:57.2 |
HIP 10347 |
1.04 |
| 2026-04-10 00:00 |
02:13:43.65 |
-35:56:42.5 |
HIP 10347 |
8.70 |
| 2026-04-10 12:00 |
02:14:04.58 |
-35:49:29.3 |
HIP 10347 |
17.04 |
| 2026-04-11 00:00 |
02:14:25.58 |
-35:42:17.7 |
HIP 10347 |
25.40 |
| 2026-04-11 12:00 |
02:14:46.64 |
-35:35:07.5 |
HIP 10441 |
24.88 |
| 2026-04-12 00:00 |
02:15:07.77 |
-35:27:58.9 |
HIP 10441 |
19.00 |
| 2026-04-12 12:00 |
02:15:28.96 |
-35:20:51.8 |
HIP 10483 |
14.27 |
| 2026-04-13 00:00 |
02:15:50.21 |
-35:13:46.3 |
HIP 10483 |
10.42 |
| 2026-04-13 12:00 |
02:16:11.53 |
-35:06:42.3 |
HIP 10483 |
12.35 |
| 2026-04-14 00:00 |
02:16:32.90 |
-34:59:39.8 |
HIP 10483 |
18.29 |
| 2026-04-14 12:00 |
02:16:54.33 |
-34:52:38.9 |
HIP 10483 |
25.58 |
| 2026-04-15 00:00 |
02:17:15.82 |
-34:45:39.6 |
HIP 10483 |
33.33 |
| 2026-04-15 12:00 |
02:17:37.36 |
-34:38:41.7 |
HIP 10483 |
41.28 |
| 2026-04-16 00:00 |
02:17:58.95 |
-34:31:45.5 |
HIP 10914 |
46.74 |