メタデータ
| 項目 |
値 |
| Designation |
C/1999 U4 (Catalina-Skiff) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2001-10-28T12:49:53.112000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:02Z |
| Obs used |
847 |
| NEO |
- |
| M1 |
10.300 |
| 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) |
2002-01-01.0000000 |
| e |
1.00756946 |
| q (au) |
4.915350 |
| a (au) |
-649.365763 |
| i (deg) |
51.925991 |
| Ω (om, deg) |
32.286666 |
| ω (w, deg) |
77.523394 |
| M (ma, deg) |
0.003840 |
等級
散乱 + 全体線形
$$
M_a = (10.223 + 3.448\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.223 |
| n |
3.448 |
| gf |
1.000 |
| gb |
-0.814 |
| k |
0.800 |
| 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 |
| 1999-09-18 |
2001-10-23 |
+6.1426 |
-5.783 |
| 2001-11-06 |
2004-04-11 |
+1.9350 |
-1.506 |
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 |
14:58:06.89 |
-47:33:52.3 |
HIP 73111 |
24.71 |
| 2026-07-29 12:00 |
14:58:06.31 |
-47:33:32.9 |
HIP 73111 |
24.90 |
| 2026-07-30 00:00 |
14:58:05.76 |
-47:33:13.5 |
HIP 73111 |
25.09 |
| 2026-07-30 12:00 |
14:58:05.25 |
-47:32:54.2 |
HIP 73111 |
25.29 |
| 2026-07-31 00:00 |
14:58:04.77 |
-47:32:35.0 |
HIP 73111 |
25.49 |
| 2026-07-31 12:00 |
14:58:04.32 |
-47:32:15.8 |
HIP 73111 |
25.70 |
| 2026-08-01 00:00 |
14:58:03.90 |
-47:31:56.7 |
HIP 73111 |
25.91 |
| 2026-08-01 12:00 |
14:58:03.51 |
-47:31:37.6 |
HIP 73111 |
26.13 |
| 2026-08-02 00:00 |
14:58:03.16 |
-47:31:18.6 |
HIP 73111 |
26.35 |
| 2026-08-02 12:00 |
14:58:02.84 |
-47:30:59.7 |
HIP 73111 |
26.58 |
| 2026-08-03 00:00 |
14:58:02.55 |
-47:30:40.8 |
HIP 73111 |
26.81 |
| 2026-08-03 12:00 |
14:58:02.29 |
-47:30:22.0 |
HIP 73111 |
27.04 |
| 2026-08-04 00:00 |
14:58:02.07 |
-47:30:03.3 |
HIP 73111 |
27.28 |
| 2026-08-04 12:00 |
14:58:01.88 |
-47:29:44.6 |
HIP 73111 |
27.52 |
| 2026-08-05 00:00 |
14:58:01.72 |
-47:29:26.0 |
HIP 73111 |
27.77 |
| 2026-08-05 12:00 |
14:58:01.59 |
-47:29:07.5 |
HIP 73111 |
28.02 |
| 2026-08-06 00:00 |
14:58:01.49 |
-47:28:49.1 |
HIP 73111 |
28.27 |
| 2026-08-06 12:00 |
14:58:01.43 |
-47:28:30.8 |
HIP 73111 |
28.52 |
| 2026-08-07 00:00 |
14:58:01.40 |
-47:28:12.5 |
HIP 73111 |
28.78 |
| 2026-08-07 12:00 |
14:58:01.40 |
-47:27:54.3 |
HIP 73111 |
29.04 |
| 2026-08-08 00:00 |
14:58:01.44 |
-47:27:36.2 |
HIP 73111 |
29.30 |
| 2026-08-08 12:00 |
14:58:01.50 |
-47:27:18.2 |
HIP 73111 |
29.57 |
| 2026-08-09 00:00 |
14:58:01.60 |
-47:27:00.3 |
HIP 73111 |
29.83 |
| 2026-08-09 12:00 |
14:58:01.74 |
-47:26:42.4 |
HIP 73111 |
30.10 |
| 2026-08-10 00:00 |
14:58:01.90 |
-47:26:24.7 |
HIP 73111 |
30.37 |
| 2026-08-10 12:00 |
14:58:02.10 |
-47:26:07.0 |
HIP 73111 |
30.64 |
| 2026-08-11 00:00 |
14:58:02.33 |
-47:25:49.5 |
HIP 73111 |
30.92 |
| 2026-08-11 12:00 |
14:58:02.59 |
-47:25:32.0 |
HIP 73111 |
31.19 |
| 2026-08-12 00:00 |
14:58:02.88 |
-47:25:14.6 |
HIP 73111 |
31.47 |
| 2026-08-12 12:00 |
14:58:03.21 |
-47:24:57.3 |
HIP 73115 |
31.74 |
| 2026-08-13 00:00 |
14:58:03.56 |
-47:24:40.1 |
HIP 73115 |
31.52 |
| 2026-08-13 12:00 |
14:58:03.96 |
-47:24:23.1 |
HIP 73115 |
31.30 |
| 2026-08-14 00:00 |
14:58:04.38 |
-47:24:06.1 |
HIP 73115 |
31.09 |
| 2026-08-14 12:00 |
14:58:04.83 |
-47:23:49.2 |
HIP 73115 |
30.89 |
| 2026-08-15 00:00 |
14:58:05.32 |
-47:23:32.4 |
HIP 73115 |
30.69 |
| 2026-08-15 12:00 |
14:58:05.84 |
-47:23:15.8 |
HIP 73115 |
30.49 |
| 2026-08-16 00:00 |
14:58:06.39 |
-47:22:59.2 |
HIP 73115 |
30.30 |
| 2026-08-16 12:00 |
14:58:06.98 |
-47:22:42.8 |
HIP 73115 |
30.12 |
| 2026-08-17 00:00 |
14:58:07.59 |
-47:22:26.4 |
HIP 73115 |
29.94 |
| 2026-08-17 12:00 |
14:58:08.24 |
-47:22:10.2 |
HIP 73115 |
29.77 |
| 2026-08-18 00:00 |
14:58:08.92 |
-47:21:54.1 |
HIP 73115 |
29.61 |
| 2026-08-18 12:00 |
14:58:09.63 |
-47:21:38.1 |
HIP 73115 |
29.45 |
| 2026-08-19 00:00 |
14:58:10.37 |
-47:21:22.2 |
HIP 73115 |
29.30 |