メタデータ
| 項目 |
値 |
| Designation |
C/2021 K3 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-02-02T08:11:00.119040Z |
| Orbit solution date (soln_date, UTC) |
2022-06-07T21:45:11Z |
| Obs used |
99 |
| NEO |
- |
| M1 |
14.500 |
| 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) |
2021-07-16.0000000 |
| e |
1.00356145 |
| q (au) |
5.230100 |
| a (au) |
-1468.531415 |
| i (deg) |
134.804408 |
| Ω (om, deg) |
114.441510 |
| ω (w, deg) |
181.948465 |
| M (ma, deg) |
-0.003526 |
等級
散乱 + 全体線形
$$
M_a = (17.424 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
17.424 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.757 |
| 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) |
| 2026-09-20 00:00 |
11:08:16.04 |
-39:58:47.6 |
HIP 54416 |
17.66 |
| 2026-09-20 12:00 |
11:08:24.26 |
-39:59:21.3 |
HIP 54416 |
18.45 |
| 2026-09-21 00:00 |
11:08:32.47 |
-39:59:55.7 |
HIP 54416 |
19.37 |
| 2026-09-21 12:00 |
11:08:40.65 |
-40:00:30.8 |
HIP 54416 |
20.39 |
| 2026-09-22 00:00 |
11:08:48.81 |
-40:01:06.5 |
HIP 54416 |
21.50 |
| 2026-09-22 12:00 |
11:08:56.95 |
-40:01:42.9 |
HIP 54416 |
22.69 |
| 2026-09-23 00:00 |
11:09:05.07 |
-40:02:20.0 |
HIP 54416 |
23.95 |
| 2026-09-23 12:00 |
11:09:13.16 |
-40:02:57.7 |
HIP 54416 |
25.26 |
| 2026-09-24 00:00 |
11:09:21.23 |
-40:03:36.1 |
HIP 54416 |
26.62 |
| 2026-09-24 12:00 |
11:09:29.27 |
-40:04:15.1 |
HIP 54416 |
28.02 |
| 2026-09-25 00:00 |
11:09:37.29 |
-40:04:54.8 |
HIP 54416 |
29.45 |
| 2026-09-25 12:00 |
11:09:45.28 |
-40:05:35.1 |
HIP 54416 |
30.92 |
| 2026-09-26 00:00 |
11:09:53.25 |
-40:06:16.1 |
HIP 54416 |
32.40 |
| 2026-09-26 12:00 |
11:10:01.19 |
-40:06:57.7 |
HIP 54416 |
33.91 |
| 2026-09-27 00:00 |
11:10:09.10 |
-40:07:40.0 |
HIP 54416 |
35.44 |
| 2026-09-27 12:00 |
11:10:16.99 |
-40:08:22.9 |
HIP 54416 |
36.99 |
| 2026-09-28 00:00 |
11:10:24.85 |
-40:09:06.4 |
HIP 54827 |
37.30 |
| 2026-09-28 12:00 |
11:10:32.68 |
-40:09:50.5 |
HIP 54827 |
36.19 |
| 2026-09-29 00:00 |
11:10:40.48 |
-40:10:35.3 |
HIP 54827 |
35.13 |
| 2026-09-29 12:00 |
11:10:48.25 |
-40:11:20.6 |
HIP 54827 |
34.14 |
| 2026-09-30 00:00 |
11:10:55.98 |
-40:12:06.6 |
HIP 54827 |
33.21 |
| 2026-09-30 12:00 |
11:11:03.69 |
-40:12:53.2 |
HIP 54827 |
32.35 |
| 2026-10-01 00:00 |
11:11:11.37 |
-40:13:40.4 |
HIP 54827 |
31.56 |
| 2026-10-01 12:00 |
11:11:19.01 |
-40:14:28.2 |
HIP 54827 |
30.86 |
| 2026-10-02 00:00 |
11:11:26.62 |
-40:15:16.7 |
HIP 54827 |
30.24 |
| 2026-10-02 12:00 |
11:11:34.20 |
-40:16:05.7 |
HIP 54827 |
29.72 |
| 2026-10-03 00:00 |
11:11:41.75 |
-40:16:55.3 |
HIP 54827 |
29.29 |
| 2026-10-03 12:00 |
11:11:49.26 |
-40:17:45.5 |
HIP 54827 |
28.96 |
| 2026-10-04 00:00 |
11:11:56.73 |
-40:18:36.2 |
HIP 54827 |
28.74 |
| 2026-10-04 12:00 |
11:12:04.17 |
-40:19:27.6 |
HIP 54827 |
28.63 |
| 2026-10-05 00:00 |
11:12:11.57 |
-40:20:19.5 |
HIP 54827 |
28.63 |
| 2026-10-05 12:00 |
11:12:18.94 |
-40:21:12.0 |
HIP 54827 |
28.73 |
| 2026-10-06 00:00 |
11:12:26.26 |
-40:22:05.1 |
HIP 54827 |
28.94 |
| 2026-10-06 12:00 |
11:12:33.55 |
-40:22:58.7 |
HIP 54827 |
29.25 |
| 2026-10-07 00:00 |
11:12:40.80 |
-40:23:52.9 |
HIP 54827 |
29.67 |
| 2026-10-07 12:00 |
11:12:48.01 |
-40:24:47.7 |
HIP 54827 |
30.18 |
| 2026-10-08 00:00 |
11:12:55.18 |
-40:25:43.0 |
HIP 54932 |
30.05 |
| 2026-10-08 12:00 |
11:13:02.31 |
-40:26:38.8 |
HIP 54932 |
29.65 |
| 2026-10-09 00:00 |
11:13:09.40 |
-40:27:35.2 |
HIP 54953 |
28.68 |
| 2026-10-09 12:00 |
11:13:16.45 |
-40:28:32.2 |
HIP 54953 |
27.03 |
| 2026-10-10 00:00 |
11:13:23.45 |
-40:29:29.6 |
HIP 54953 |
25.39 |
| 2026-10-10 12:00 |
11:13:30.41 |
-40:30:27.6 |
HIP 54953 |
23.76 |
| 2026-10-11 00:00 |
11:13:37.32 |
-40:31:26.1 |
HIP 54953 |
22.12 |