メタデータ
| 項目 |
値 |
| Designation |
C/2021 U5 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-01-26T14:41:49.295040Z |
| Orbit solution date (soln_date, UTC) |
2022-11-29T21:43:26Z |
| Obs used |
463 |
| NEO |
- |
| M1 |
4.800 |
| K1 |
28.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-10-29T11:47:30.652800Z |
| Discovery magnitude (MPC) |
19.16 G |
| Discovery observatory (MPC) |
703 · University of Arizona Catalina Sky Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2022-02-19.0000000 |
| e |
0.98911516 |
| q (au) |
2.363288 |
| a (au) |
217.117490 |
| i (deg) |
39.049400 |
| Ω (om, deg) |
182.755199 |
| ω (w, deg) |
321.471259 |
| M (ma, deg) |
0.007205 |
等級
散乱 + 全体線形
$$
M_a = (12.219 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.219 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.744 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
18:22:42.89 |
+18:25:34.4 |
HIP 89972 |
23.70 |
| 2026-06-01 12:00 |
18:22:35.39 |
+18:26:09.0 |
HIP 89972 |
22.75 |
| 2026-06-02 00:00 |
18:22:27.86 |
+18:26:42.7 |
HIP 89972 |
21.91 |
| 2026-06-02 12:00 |
18:22:20.29 |
+18:27:15.8 |
HIP 89972 |
21.18 |
| 2026-06-03 00:00 |
18:22:12.69 |
+18:27:48.0 |
HIP 89972 |
20.59 |
| 2026-06-03 12:00 |
18:22:05.05 |
+18:28:19.5 |
HIP 89972 |
20.14 |
| 2026-06-04 00:00 |
18:21:57.38 |
+18:28:50.2 |
HIP 89972 |
19.85 |
| 2026-06-04 12:00 |
18:21:49.68 |
+18:29:20.1 |
HIP 89972 |
19.72 |
| 2026-06-05 00:00 |
18:21:41.94 |
+18:29:49.2 |
HIP 89972 |
19.75 |
| 2026-06-05 12:00 |
18:21:34.18 |
+18:30:17.5 |
HIP 89972 |
19.96 |
| 2026-06-06 00:00 |
18:21:26.39 |
+18:30:45.1 |
HIP 89972 |
20.32 |
| 2026-06-06 12:00 |
18:21:18.56 |
+18:31:11.9 |
HIP 89972 |
20.85 |
| 2026-06-07 00:00 |
18:21:10.71 |
+18:31:37.8 |
HIP 89972 |
21.51 |
| 2026-06-07 12:00 |
18:21:02.83 |
+18:32:03.0 |
HIP 89972 |
22.32 |
| 2026-06-08 00:00 |
18:20:54.92 |
+18:32:27.4 |
HIP 89972 |
23.24 |
| 2026-06-08 12:00 |
18:20:46.99 |
+18:32:50.9 |
HIP 89972 |
24.27 |
| 2026-06-09 00:00 |
18:20:39.03 |
+18:33:13.7 |
HIP 89749 |
24.77 |
| 2026-06-09 12:00 |
18:20:31.05 |
+18:33:35.6 |
HIP 89749 |
22.98 |
| 2026-06-10 00:00 |
18:20:23.04 |
+18:33:56.8 |
HIP 89749 |
21.19 |
| 2026-06-10 12:00 |
18:20:15.01 |
+18:34:17.1 |
HIP 89749 |
19.43 |
| 2026-06-11 00:00 |
18:20:06.96 |
+18:34:36.6 |
HIP 89749 |
17.70 |
| 2026-06-11 12:00 |
18:19:58.89 |
+18:34:55.3 |
HIP 89749 |
16.00 |
| 2026-06-12 00:00 |
18:19:50.80 |
+18:35:13.2 |
HIP 89749 |
14.35 |
| 2026-06-12 12:00 |
18:19:42.68 |
+18:35:30.2 |
HIP 89749 |
12.77 |
| 2026-06-13 00:00 |
18:19:34.55 |
+18:35:46.5 |
HIP 89749 |
11.30 |
| 2026-06-13 12:00 |
18:19:26.40 |
+18:36:01.9 |
HIP 89749 |
9.97 |
| 2026-06-14 00:00 |
18:19:18.24 |
+18:36:16.5 |
HIP 89749 |
8.87 |
| 2026-06-14 12:00 |
18:19:10.05 |
+18:36:30.2 |
HIP 89749 |
8.08 |
| 2026-06-15 00:00 |
18:19:01.86 |
+18:36:43.1 |
HIP 89749 |
7.70 |
| 2026-06-15 12:00 |
18:18:53.64 |
+18:36:55.2 |
HIP 89749 |
7.79 |
| 2026-06-16 00:00 |
18:18:45.42 |
+18:37:06.5 |
HIP 89749 |
8.34 |
| 2026-06-16 12:00 |
18:18:37.18 |
+18:37:16.9 |
HIP 89749 |
9.27 |
| 2026-06-17 00:00 |
18:18:28.93 |
+18:37:26.5 |
HIP 89749 |
10.48 |
| 2026-06-17 12:00 |
18:18:20.67 |
+18:37:35.3 |
HIP 89749 |
11.88 |
| 2026-06-18 00:00 |
18:18:12.40 |
+18:37:43.2 |
HIP 89749 |
13.42 |
| 2026-06-18 12:00 |
18:18:04.13 |
+18:37:50.3 |
HIP 89749 |
15.05 |
| 2026-06-19 00:00 |
18:17:55.84 |
+18:37:56.5 |
HIP 89749 |
16.74 |
| 2026-06-19 12:00 |
18:17:47.55 |
+18:38:02.0 |
HIP 89749 |
18.49 |
| 2026-06-20 00:00 |
18:17:39.25 |
+18:38:06.6 |
HIP 89711 |
19.76 |
| 2026-06-20 12:00 |
18:17:30.95 |
+18:38:10.3 |
HIP 89711 |
21.11 |
| 2026-06-21 00:00 |
18:17:22.64 |
+18:38:13.3 |
HIP 89711 |
22.55 |
| 2026-06-21 12:00 |
18:17:14.33 |
+18:38:15.4 |
HIP 89610 |
24.05 |
| 2026-06-22 00:00 |
18:17:06.01 |
+18:38:16.6 |
HIP 89610 |
24.08 |