メタデータ
| 項目 |
値 |
| Designation |
172P/Yeung |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-03-10T18:58:47.357760Z |
| Orbit solution date (soln_date, UTC) |
2026-07-16T19:12:25Z |
| Obs used |
802 |
| NEO |
- |
| M1 |
14.800 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2013-07-18.0000000 |
| e |
0.22314683 |
| q (au) |
3.246010 |
| a (au) |
4.178409 |
| i (deg) |
11.306057 |
| Ω (om, deg) |
33.521274 |
| ω (w, deg) |
208.801998 |
| M (ma, deg) |
206.317744 |
等級
散乱 + 全体線形
$$
M_a = (14.025 + 2.597\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.025 |
| n |
2.597 |
| gf |
0.995 |
| gb |
-0.747 |
| k |
0.986 |
| 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) |
| 2026-07-29 00:00 |
18:34:22.40 |
-37:48:46.5 |
HIP 91017 |
7.52 |
| 2026-07-29 12:00 |
18:34:05.81 |
-37:48:07.7 |
HIP 91017 |
5.71 |
| 2026-07-30 00:00 |
18:33:49.49 |
-37:47:27.6 |
HIP 91017 |
5.53 |
| 2026-07-30 12:00 |
18:33:33.45 |
-37:46:46.1 |
HIP 91017 |
7.03 |
| 2026-07-31 00:00 |
18:33:17.69 |
-37:46:03.3 |
HIP 91017 |
9.39 |
| 2026-07-31 12:00 |
18:33:02.21 |
-37:45:19.1 |
HIP 91017 |
12.08 |
| 2026-08-01 00:00 |
18:32:47.01 |
-37:44:33.7 |
HIP 91017 |
14.89 |
| 2026-08-01 12:00 |
18:32:32.10 |
-37:43:46.9 |
HIP 90800 |
15.74 |
| 2026-08-02 00:00 |
18:32:17.47 |
-37:42:58.9 |
HIP 90800 |
12.88 |
| 2026-08-02 12:00 |
18:32:03.14 |
-37:42:09.6 |
HIP 90800 |
10.13 |
| 2026-08-03 00:00 |
18:31:49.11 |
-37:41:19.1 |
HIP 90800 |
7.56 |
| 2026-08-03 12:00 |
18:31:35.37 |
-37:40:27.4 |
HIP 90800 |
5.35 |
| 2026-08-04 00:00 |
18:31:21.93 |
-37:39:34.5 |
HIP 90800 |
4.01 |
| 2026-08-04 12:00 |
18:31:08.79 |
-37:38:40.4 |
HIP 90800 |
4.34 |
| 2026-08-05 00:00 |
18:30:55.95 |
-37:37:45.1 |
HIP 90800 |
6.00 |
| 2026-08-05 12:00 |
18:30:43.43 |
-37:36:48.7 |
HIP 90800 |
8.17 |
| 2026-08-06 00:00 |
18:30:31.21 |
-37:35:51.2 |
HIP 90800 |
10.50 |
| 2026-08-06 12:00 |
18:30:19.31 |
-37:34:52.6 |
HIP 90800 |
12.88 |
| 2026-08-07 00:00 |
18:30:07.71 |
-37:33:52.9 |
HIP 90800 |
15.25 |
| 2026-08-07 12:00 |
18:29:56.44 |
-37:32:52.1 |
HIP 90800 |
17.60 |
| 2026-08-08 00:00 |
18:29:45.48 |
-37:31:50.3 |
HIP 90800 |
19.92 |
| 2026-08-08 12:00 |
18:29:34.84 |
-37:30:47.5 |
HIP 90511 |
19.40 |
| 2026-08-09 00:00 |
18:29:24.53 |
-37:29:43.6 |
HIP 90511 |
17.10 |
| 2026-08-09 12:00 |
18:29:14.54 |
-37:28:38.8 |
HIP 90511 |
14.84 |
| 2026-08-10 00:00 |
18:29:04.87 |
-37:27:33.0 |
HIP 90511 |
12.65 |
| 2026-08-10 12:00 |
18:28:55.53 |
-37:26:26.2 |
HIP 90511 |
10.51 |
| 2026-08-11 00:00 |
18:28:46.53 |
-37:25:18.5 |
HIP 90511 |
8.44 |
| 2026-08-11 12:00 |
18:28:37.85 |
-37:24:09.8 |
HIP 90511 |
6.47 |
| 2026-08-12 00:00 |
18:28:29.51 |
-37:23:00.3 |
HIP 90511 |
4.63 |
| 2026-08-12 12:00 |
18:28:21.50 |
-37:21:49.9 |
HIP 90511 |
3.12 |
| 2026-08-13 00:00 |
18:28:13.82 |
-37:20:38.6 |
HIP 90511 |
2.45 |
| 2026-08-13 12:00 |
18:28:06.48 |
-37:19:26.5 |
HIP 90511 |
3.14 |
| 2026-08-14 00:00 |
18:27:59.49 |
-37:18:13.5 |
HIP 90511 |
4.56 |
| 2026-08-14 12:00 |
18:27:52.83 |
-37:16:59.8 |
HIP 90511 |
6.20 |
| 2026-08-15 00:00 |
18:27:46.50 |
-37:15:45.2 |
HIP 90511 |
7.88 |
| 2026-08-15 12:00 |
18:27:40.52 |
-37:14:29.9 |
HIP 90511 |
9.57 |
| 2026-08-16 00:00 |
18:27:34.88 |
-37:13:13.8 |
HIP 90511 |
11.25 |
| 2026-08-16 12:00 |
18:27:29.59 |
-37:11:57.0 |
HIP 90511 |
12.90 |
| 2026-08-17 00:00 |
18:27:24.63 |
-37:10:39.5 |
HIP 90511 |
14.52 |
| 2026-08-17 12:00 |
18:27:20.02 |
-37:09:21.2 |
HIP 90511 |
16.12 |
| 2026-08-18 00:00 |
18:27:15.75 |
-37:08:02.3 |
HIP 90511 |
17.68 |
| 2026-08-18 12:00 |
18:27:11.82 |
-37:06:42.7 |
HIP 90511 |
19.22 |
| 2026-08-19 00:00 |
18:27:08.23 |
-37:05:22.5 |
HIP 90302 |
19.62 |