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) |
| 2026-06-01 00:00 |
15:02:27.99 |
-48:10:14.8 |
HIP 73622 |
14.58 |
| 2026-06-01 12:00 |
15:02:24.45 |
-48:10:00.4 |
HIP 73622 |
14.57 |
| 2026-06-02 00:00 |
15:02:20.92 |
-48:09:45.9 |
HIP 73622 |
14.58 |
| 2026-06-02 12:00 |
15:02:17.41 |
-48:09:31.2 |
HIP 73622 |
14.62 |
| 2026-06-03 00:00 |
15:02:13.92 |
-48:09:16.4 |
HIP 73622 |
14.68 |
| 2026-06-03 12:00 |
15:02:10.44 |
-48:09:01.5 |
HIP 73622 |
14.77 |
| 2026-06-04 00:00 |
15:02:06.97 |
-48:08:46.4 |
HIP 73622 |
14.88 |
| 2026-06-04 12:00 |
15:02:03.52 |
-48:08:31.2 |
HIP 73622 |
15.01 |
| 2026-06-05 00:00 |
15:02:00.09 |
-48:08:15.9 |
HIP 73622 |
15.16 |
| 2026-06-05 12:00 |
15:01:56.67 |
-48:08:00.5 |
HIP 73622 |
15.34 |
| 2026-06-06 00:00 |
15:01:53.26 |
-48:07:44.9 |
HIP 73622 |
15.53 |
| 2026-06-06 12:00 |
15:01:49.88 |
-48:07:29.2 |
HIP 73622 |
15.74 |
| 2026-06-07 00:00 |
15:01:46.51 |
-48:07:13.4 |
HIP 73622 |
15.97 |
| 2026-06-07 12:00 |
15:01:43.15 |
-48:06:57.4 |
HIP 73622 |
16.22 |
| 2026-06-08 00:00 |
15:01:39.82 |
-48:06:41.3 |
HIP 73622 |
16.49 |
| 2026-06-08 12:00 |
15:01:36.50 |
-48:06:25.2 |
HIP 73622 |
16.77 |
| 2026-06-09 00:00 |
15:01:33.19 |
-48:06:08.8 |
HIP 73622 |
17.06 |
| 2026-06-09 12:00 |
15:01:29.91 |
-48:05:52.4 |
HIP 73622 |
17.37 |
| 2026-06-10 00:00 |
15:01:26.64 |
-48:05:35.9 |
HIP 73622 |
17.69 |
| 2026-06-10 12:00 |
15:01:23.40 |
-48:05:19.2 |
HIP 73622 |
18.02 |
| 2026-06-11 00:00 |
15:01:20.17 |
-48:05:02.4 |
HIP 73622 |
18.36 |
| 2026-06-11 12:00 |
15:01:16.96 |
-48:04:45.6 |
HIP 73622 |
18.72 |
| 2026-06-12 00:00 |
15:01:13.77 |
-48:04:28.6 |
HIP 73622 |
19.08 |
| 2026-06-12 12:00 |
15:01:10.59 |
-48:04:11.5 |
HIP 73622 |
19.45 |
| 2026-06-13 00:00 |
15:01:07.44 |
-48:03:54.3 |
HIP 73622 |
19.82 |
| 2026-06-13 12:00 |
15:01:04.31 |
-48:03:37.0 |
HIP 73622 |
20.21 |
| 2026-06-14 00:00 |
15:01:01.20 |
-48:03:19.5 |
HIP 73332 |
19.98 |
| 2026-06-14 12:00 |
15:00:58.11 |
-48:03:02.0 |
HIP 73332 |
19.39 |
| 2026-06-15 00:00 |
15:00:55.03 |
-48:02:44.4 |
HIP 73332 |
18.82 |
| 2026-06-15 12:00 |
15:00:51.98 |
-48:02:26.7 |
HIP 73332 |
18.24 |
| 2026-06-16 00:00 |
15:00:48.96 |
-48:02:08.9 |
HIP 73332 |
17.67 |
| 2026-06-16 12:00 |
15:00:45.95 |
-48:01:51.0 |
HIP 73332 |
17.10 |
| 2026-06-17 00:00 |
15:00:42.96 |
-48:01:33.0 |
HIP 73332 |
16.54 |
| 2026-06-17 12:00 |
15:00:40.00 |
-48:01:14.9 |
HIP 73332 |
15.98 |
| 2026-06-18 00:00 |
15:00:37.06 |
-48:00:56.8 |
HIP 73332 |
15.43 |
| 2026-06-18 12:00 |
15:00:34.14 |
-48:00:38.5 |
HIP 73332 |
14.88 |
| 2026-06-19 00:00 |
15:00:31.24 |
-48:00:20.2 |
HIP 73332 |
14.34 |
| 2026-06-19 12:00 |
15:00:28.37 |
-48:00:01.7 |
HIP 73332 |
13.80 |
| 2026-06-20 00:00 |
15:00:25.52 |
-47:59:43.2 |
HIP 73332 |
13.27 |
| 2026-06-20 12:00 |
15:00:22.69 |
-47:59:24.7 |
HIP 73332 |
12.74 |
| 2026-06-21 00:00 |
15:00:19.88 |
-47:59:06.0 |
HIP 73332 |
12.22 |
| 2026-06-21 12:00 |
15:00:17.10 |
-47:58:47.3 |
HIP 73332 |
11.71 |
| 2026-06-22 00:00 |
15:00:14.35 |
-47:58:28.4 |
HIP 73332 |
11.21 |