メタデータ
| 項目 |
値 |
| Designation |
C/2018 W1 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-05-11T20:28:13.800000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:48Z |
| Obs used |
287 |
| NEO |
- |
| M1 |
14.000 |
| K1 |
10.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-11-16T04:47:27.168000Z |
| Discovery magnitude (MPC) |
19.80 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) |
2019-01-26.0000000 |
| e |
0.93766329 |
| q (au) |
1.360177 |
| a (au) |
21.819838 |
| i (deg) |
83.278879 |
| Ω (om, deg) |
233.589579 |
| ω (w, deg) |
251.248066 |
| M (ma, deg) |
358.976401 |
等級
散乱 + 全体線形
$$
M_a = (11.588 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.588 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.941 |
| k |
0.999 |
| 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 |
| 2018-11-16 |
2019-03-08 |
-1.4661 |
+0.573 |
| 2019-05-26 |
2020-05-21 |
+6.2919 |
-4.653 |
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 |
16:30:44.49 |
+26:55:42.5 |
HIP 80876 |
23.18 |
| 2026-06-01 12:00 |
16:30:37.00 |
+26:56:00.3 |
HIP 80876 |
23.03 |
| 2026-06-02 00:00 |
16:30:29.52 |
+26:56:17.3 |
HIP 80876 |
23.01 |
| 2026-06-02 12:00 |
16:30:22.04 |
+26:56:33.7 |
HIP 80876 |
23.13 |
| 2026-06-03 00:00 |
16:30:14.57 |
+26:56:49.4 |
HIP 80876 |
23.38 |
| 2026-06-03 12:00 |
16:30:07.10 |
+26:57:04.4 |
HIP 80876 |
23.76 |
| 2026-06-04 00:00 |
16:29:59.64 |
+26:57:18.6 |
HIP 80876 |
24.26 |
| 2026-06-04 12:00 |
16:29:52.19 |
+26:57:32.2 |
HIP 80876 |
24.87 |
| 2026-06-05 00:00 |
16:29:44.74 |
+26:57:45.1 |
HIP 80876 |
25.58 |
| 2026-06-05 12:00 |
16:29:37.30 |
+26:57:57.2 |
HIP 80876 |
26.39 |
| 2026-06-06 00:00 |
16:29:29.87 |
+26:58:08.7 |
HIP 80876 |
27.28 |
| 2026-06-06 12:00 |
16:29:22.45 |
+26:58:19.5 |
HIP 80594 |
28.09 |
| 2026-06-07 00:00 |
16:29:15.04 |
+26:58:29.5 |
HIP 80594 |
26.50 |
| 2026-06-07 12:00 |
16:29:07.64 |
+26:58:38.9 |
HIP 80594 |
24.92 |
| 2026-06-08 00:00 |
16:29:00.25 |
+26:58:47.5 |
HIP 80594 |
23.35 |
| 2026-06-08 12:00 |
16:28:52.87 |
+26:58:55.5 |
HIP 80594 |
21.79 |
| 2026-06-09 00:00 |
16:28:45.51 |
+26:59:02.8 |
HIP 80594 |
20.25 |
| 2026-06-09 12:00 |
16:28:38.16 |
+26:59:09.3 |
HIP 80594 |
18.72 |
| 2026-06-10 00:00 |
16:28:30.82 |
+26:59:15.2 |
HIP 80594 |
17.21 |
| 2026-06-10 12:00 |
16:28:23.49 |
+26:59:20.3 |
HIP 80594 |
15.73 |
| 2026-06-11 00:00 |
16:28:16.19 |
+26:59:24.8 |
HIP 80594 |
14.28 |
| 2026-06-11 12:00 |
16:28:08.89 |
+26:59:28.6 |
HIP 80594 |
12.87 |
| 2026-06-12 00:00 |
16:28:01.61 |
+26:59:31.6 |
HIP 80594 |
11.51 |
| 2026-06-12 12:00 |
16:27:54.35 |
+26:59:34.0 |
HIP 80594 |
10.23 |
| 2026-06-13 00:00 |
16:27:47.11 |
+26:59:35.7 |
HIP 80594 |
9.05 |
| 2026-06-13 12:00 |
16:27:39.89 |
+26:59:36.6 |
HIP 80594 |
8.01 |
| 2026-06-14 00:00 |
16:27:32.68 |
+26:59:36.9 |
HIP 80594 |
7.18 |
| 2026-06-14 12:00 |
16:27:25.50 |
+26:59:36.5 |
HIP 80594 |
6.64 |
| 2026-06-15 00:00 |
16:27:18.33 |
+26:59:35.4 |
HIP 80594 |
6.44 |
| 2026-06-15 12:00 |
16:27:11.19 |
+26:59:33.6 |
HIP 80594 |
6.62 |
| 2026-06-16 00:00 |
16:27:04.06 |
+26:59:31.1 |
HIP 80594 |
7.14 |
| 2026-06-16 12:00 |
16:26:56.96 |
+26:59:27.9 |
HIP 80594 |
7.94 |
| 2026-06-17 00:00 |
16:26:49.88 |
+26:59:24.0 |
HIP 80594 |
8.94 |
| 2026-06-17 12:00 |
16:26:42.83 |
+26:59:19.5 |
HIP 80594 |
10.08 |
| 2026-06-18 00:00 |
16:26:35.80 |
+26:59:14.3 |
HIP 80594 |
11.32 |
| 2026-06-18 12:00 |
16:26:28.79 |
+26:59:08.4 |
HIP 80594 |
12.61 |
| 2026-06-19 00:00 |
16:26:21.81 |
+26:59:01.8 |
HIP 80594 |
13.96 |
| 2026-06-19 12:00 |
16:26:14.86 |
+26:58:54.5 |
HIP 80594 |
15.33 |
| 2026-06-20 00:00 |
16:26:07.93 |
+26:58:46.6 |
HIP 80594 |
16.73 |
| 2026-06-20 12:00 |
16:26:01.03 |
+26:58:38.0 |
HIP 80594 |
18.14 |
| 2026-06-21 00:00 |
16:25:54.15 |
+26:58:28.7 |
HIP 80594 |
19.56 |
| 2026-06-21 12:00 |
16:25:47.31 |
+26:58:18.8 |
HIP 80594 |
20.99 |
| 2026-06-22 00:00 |
16:25:40.49 |
+26:58:08.2 |
HIP 80594 |
22.43 |