メタデータ
| 項目 |
値 |
| Designation |
C/2009 U3 (Hill) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2010-03-20T06:06:49.440960Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:36Z |
| Obs used |
602 |
| NEO |
- |
| M1 |
15.400 |
| K1 |
6.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2010-01-01.0000000 |
| e |
0.99157651 |
| q (au) |
1.414425 |
| a (au) |
167.914294 |
| i (deg) |
51.260767 |
| Ω (om, deg) |
49.322883 |
| ω (w, deg) |
77.701400 |
| M (ma, deg) |
359.964553 |
等級
散乱 + 全体線形
$$
M_a = (13.668 + 5.160\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.668 |
| n |
5.160 |
| gf |
1.000 |
| gb |
-0.772 |
| k |
0.984 |
| δ90 |
9.994 |
| 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 |
| 2009-10-20 |
2009-11-16 |
-11.6949 |
+4.120 |
| 2009-11-16 |
2009-12-24 |
+7.8048 |
-2.355 |
| 2009-12-24 |
2010-01-26 |
-15.1111 |
+3.692 |
| 2010-01-26 |
2010-03-19 |
+34.3857 |
-6.645 |
| 2010-03-24 |
2010-05-14 |
+6.6096 |
-1.956 |
| 2010-05-14 |
2010-06-18 |
-14.3864 |
+3.611 |
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) |
| 2026-07-29 00:00 |
18:01:32.04 |
-64:15:57.4 |
HIP 88170 |
14.94 |
| 2026-07-29 12:00 |
18:01:25.89 |
-64:15:38.9 |
HIP 88170 |
14.36 |
| 2026-07-30 00:00 |
18:01:19.79 |
-64:15:20.1 |
HIP 88170 |
13.79 |
| 2026-07-30 12:00 |
18:01:13.74 |
-64:15:01.0 |
HIP 88170 |
13.23 |
| 2026-07-31 00:00 |
18:01:07.72 |
-64:14:41.7 |
HIP 88170 |
12.69 |
| 2026-07-31 12:00 |
18:01:01.76 |
-64:14:22.2 |
HIP 88170 |
12.16 |
| 2026-08-01 00:00 |
18:00:55.84 |
-64:14:02.4 |
HIP 88170 |
11.66 |
| 2026-08-01 12:00 |
18:00:49.96 |
-64:13:42.4 |
HIP 88170 |
11.18 |
| 2026-08-02 00:00 |
18:00:44.14 |
-64:13:22.2 |
HIP 88170 |
10.72 |
| 2026-08-02 12:00 |
18:00:38.35 |
-64:13:01.8 |
HIP 88170 |
10.28 |
| 2026-08-03 00:00 |
18:00:32.62 |
-64:12:41.1 |
HIP 88170 |
9.88 |
| 2026-08-03 12:00 |
18:00:26.93 |
-64:12:20.2 |
HIP 88170 |
9.51 |
| 2026-08-04 00:00 |
18:00:21.30 |
-64:11:59.0 |
HIP 88170 |
9.18 |
| 2026-08-04 12:00 |
18:00:15.71 |
-64:11:37.7 |
HIP 88170 |
8.88 |
| 2026-08-05 00:00 |
18:00:10.17 |
-64:11:16.1 |
HIP 88170 |
8.63 |
| 2026-08-05 12:00 |
18:00:04.68 |
-64:10:54.3 |
HIP 88170 |
8.43 |
| 2026-08-06 00:00 |
17:59:59.24 |
-64:10:32.2 |
HIP 88170 |
8.27 |
| 2026-08-06 12:00 |
17:59:53.85 |
-64:10:10.0 |
HIP 88170 |
8.17 |
| 2026-08-07 00:00 |
17:59:48.51 |
-64:09:47.6 |
HIP 88170 |
8.12 |
| 2026-08-07 12:00 |
17:59:43.22 |
-64:09:24.9 |
HIP 88170 |
8.12 |
| 2026-08-08 00:00 |
17:59:37.99 |
-64:09:02.0 |
HIP 88170 |
8.17 |
| 2026-08-08 12:00 |
17:59:32.80 |
-64:08:39.0 |
HIP 88170 |
8.28 |
| 2026-08-09 00:00 |
17:59:27.67 |
-64:08:15.7 |
HIP 88170 |
8.43 |
| 2026-08-09 12:00 |
17:59:22.59 |
-64:07:52.2 |
HIP 88170 |
8.63 |
| 2026-08-10 00:00 |
17:59:17.57 |
-64:07:28.5 |
HIP 88170 |
8.87 |
| 2026-08-10 12:00 |
17:59:12.60 |
-64:07:04.6 |
HIP 88170 |
9.14 |
| 2026-08-11 00:00 |
17:59:07.68 |
-64:06:40.5 |
HIP 88170 |
9.45 |
| 2026-08-11 12:00 |
17:59:02.82 |
-64:06:16.3 |
HIP 88170 |
9.79 |
| 2026-08-12 00:00 |
17:58:58.02 |
-64:05:51.8 |
HIP 88170 |
10.15 |
| 2026-08-12 12:00 |
17:58:53.27 |
-64:05:27.1 |
HIP 88170 |
10.54 |
| 2026-08-13 00:00 |
17:58:48.57 |
-64:05:02.3 |
HIP 88170 |
10.95 |
| 2026-08-13 12:00 |
17:58:43.93 |
-64:04:37.3 |
HIP 88170 |
11.37 |
| 2026-08-14 00:00 |
17:58:39.35 |
-64:04:12.1 |
HIP 88170 |
11.81 |
| 2026-08-14 12:00 |
17:58:34.83 |
-64:03:46.7 |
HIP 88170 |
12.27 |
| 2026-08-15 00:00 |
17:58:30.36 |
-64:03:21.1 |
HIP 88170 |
12.73 |
| 2026-08-15 12:00 |
17:58:25.95 |
-64:02:55.4 |
HIP 88170 |
13.20 |
| 2026-08-16 00:00 |
17:58:21.60 |
-64:02:29.5 |
HIP 88170 |
13.69 |
| 2026-08-16 12:00 |
17:58:17.31 |
-64:02:03.4 |
HIP 88170 |
14.17 |
| 2026-08-17 00:00 |
17:58:13.07 |
-64:01:37.2 |
HIP 88170 |
14.67 |
| 2026-08-17 12:00 |
17:58:08.90 |
-64:01:10.8 |
HIP 88170 |
15.17 |
| 2026-08-18 00:00 |
17:58:04.78 |
-64:00:44.2 |
HIP 88170 |
15.67 |
| 2026-08-18 12:00 |
17:58:00.73 |
-64:00:17.5 |
HIP 88170 |
16.18 |
| 2026-08-19 00:00 |
17:57:56.73 |
-63:59:50.6 |
HIP 88170 |
16.69 |